IT Support Course Flashcards
(972 cards)
1
Q
Bit
A
The smallest representation of data that a computer can understand
2
Q
Border Gateway Protocol (BGP)
A
A protocol by which routers share data with each other
3
Q
Broadcast
A
A type of Ethernet transmission, sent to every single device on a LAN
4
Q
Broadcast address
A
A special destination used by an Ethernet broadcast composed by all Fs
5
Q
Cable categories
A
Groups of cables that are made with the same material. Most network cables used today can be split into two categories, copper and fiber
6
Q
Cables
A
Insulated wires that connect different devices to each other allowing data to be transmitted over them
7
Q
Carrier-Sense Multiple Access with Collision Detection (CSMA/CD)
A
CSMA/CD is used to determine when the communications channels are clear and when the device is free to transmit data
8
Q
Client
A
A device that receives data from a server
9
Q
Collision domain
A
A network segment where only one device can communicate at a time
10
Q
Computer networking
A
The full scope of how computers communicate with each other
11
Q
Copper cable categories
A
These categories have different physical characteristics like the number of twists in the pair of copper wires. These are defined as names like category (or cat) 5, 5e, or 6, and how quickly data can be sent across them and how resistant they are to outside interference are all related to the way the twisted pairs inside are arranged
12
Q
Crosstalk
A
Crosstalk is when an electrical pulse on one wire is accidentally detected on another wire
13
Q
Cyclical Redundancy Check (CRC)
A
A mathematical transformation that uses polynomial division to create a number that represents a larger set of data. It is an important concept for data integrity and is used all over computing, not just network transmissions
14
Q
Data packet
A
An all-encompassing term that represents any single set of binary data being sent across a network link
15
Q
Datalink layer
A
The layer in which the first protocols are introduced. This layer is responsible for defining a common way of interpreting signals, so network devices can communicate
16
Q
Destination MAC address
A
The hardware address of the intended recipient that immediately follows the start frame delimiter
17
Q
Duplex communication
A
A form of communication where information can flow in both directions across a cable
18
Q
Ethernet
A
The protocol most widely used to send data across individual links
19
Q
Ethernet frame
A
A highly structured collection of information presented in a specific order
20
Q
EtherType field
A
It follows the Source MAC Address in a dataframe. It’s 16 bits long and used to describe the protocol of the contents of the frame
21
Q
Fiber Optic cable
A
Fiber optic cables contain individual optical fibers which are tiny tubes made of glass about the width of a human hair. Unlike copper, which uses electrical voltages, fiber cables use pulses of light to represent the ones and zeros of the underlying data
22
Q
Five layer model
A
A model used to explain how network devices communicate. This model has five layers that stack on top of each other: Physical, Data Link, Network, Transport, and Application
23
Q
Frame check sequence
A
It is a 4-byte or 32-bit number that represents a checksum value for the entire frame
24
Q
Full duplex
A
The capacity of devices on either side of a networking link to communicate with each other at the exact same time
25
Half-duplex
It means that, while communication is possible in each direction, only one device can be communicating at a time
26
Hexadecimal
A way to represent numbers using a numerical base of 16
27
Hub
It is a physical layer device that broadcasts data to everything computer connected to it
28
Internet Protocol (IP)
The most common protocol used in the network layer
29
Internet Service Provider (ISP)
A company that provides a consumer an internet connection
30
Internetwork
A collection of networks connected together through routers - the most famous of these being the Internet
31
Line coding
Modulation used for computer networks
32
Local Area Network (LAN)
A single network in which multiple devices are connected
33
MAC(Media Access Control) address
A globally unique identifier attached to an individual network interface. It's a 48-bit number normally represented by six groupings of two hexadecimal numbers
34
Modulation
A way of varying the voltage of a constant electrical charge moving across a standard copper network cable
35
Multicast frame
If the least significant bit in the first octet of a destination address is set to one, it means you're dealing with a multicast frame. A multicast frame is similarly set to all devices on the local network signal, and it will be accepted or discarded by each device depending on criteria aside from their own hardware MAC address
36
Network layer
It's the layer that allows different networks to communicate with each other through devices known as routers. It is responsible for getting data delivered across a collection of networks
37
Network port
The physical connector to be able to connect a device to the network. This may be attached directly to a device on a computer network, or could also be located on a wall or on a patch panel
38
Network switch
It is a level 2 or data link device that can connect to many devices so they can communicate. It can inspect the contents of the Ethernet protocol data being sent around the network, determine which system the data is intended for and then only send that data to that one system
39
Node
Any device connected to a network. On most networks, each node will typically act as a server or a client
40
Octet
Any number that can be represented by 8 bits
41
Organizationally Unique Identifier (OUI)
The first three octets of a MAC address
42
OSI model
A model used to define how network devices communicate. This model has seven layers that stack on top of each other: Physical, Data Link, Network, Transport, Session, Presentation, and Application
43
Patch panel
A device containing many physical network ports
44
Payload
The actual data being transported, which is everything that isn't a header
45
Physical layer
It represents the physical devices that interconnect computers
46
Preamble
The first part of an Ethernet frame, it is 8 bytes or 64 bits long and can itself be split into two sections
47
Protocol
A defined set of standards that computers must follow in order to communicate properly is called a protocol
48
Router
A device that knows how to forward data between independent networks
49
Server
A device that provides data to another device that is requesting that data, also known as a client
50
Simplex communication
A form of data communication that only goes in one direction across a cable
51
Source MAC address
The hardware address of the device that sent the ethernet frame or data packet. In the data packet it follows the destination MAC address
52
Start Frame Delimiter (SFD)
The last byte in the preamble, that signals to a receiving device that the preamble is over and that the actual frame contents will now follow
53
Transmission Control Protocol (TCP)
The data transfer protocol most commonly used in the fourth layer. This protocol requires an established connection between the client and server
54
Transport layer
The network layer that sorts out which client and server programs are supposed to get the data
55
Twisted pair cable
The most common type of cabling used for connecting computing devices. It features pairs of copper wires that are twisted together
56
Unicast transmission
A unicast transmission is always meant for just one receiving address
57
User Datagram Protocol (UDP)
A transfer protocol that does not rely on connections. This protocol does not support the concept of an acknowledgement. With UDP, you just set a destination port and send the data packet
58
Virtual LAN (VLAN)
It is a technique that lets you have multiple logical LANs operating on the same physical equipment
59
VLAN header
A piece of data that indicates what the frame itself is. In a data packet it is followed by the EtherType
60
802.1X
It is the IEEE standard for encapsulating EAP or Extensible Authentication Protocol traffic over the 802 networks
61
802.1X with EAP-TLS
Offers arguably the best security available, assuming proper and secure handling of the PKI aspects of it
62
Access Control Entries
The individual access permissions per object that make up the ACL
63
Access Control List (ACL)
It is a way of defining permissions or authorizations for objects
64
Accounting
Keeping records of what resources and services your users access or what they did when they were using your systems
65
Activation threshold
Triggers a pre-configured action when it is reached and will typically block the identified attack traffic for a specific amount of time
66
Advanced Encryption Standard (AES)
The first and only public cipher that's approved for use with top secret information by the United States National Security Agency
67
Adware
Software that displays advertisements and collects data
68
Analyzing logs
The practice of collecting logs from different network and sometimes client devices on your network, then performing an automated analysis on them
69
Antivirus software
It monitors and analyze things like new files being created or being modified on the system in order to watch for any behavior that matches a known malware signature
70
Application policies
Defines boundaries of what applications are permitted or not, but they also help educate folks on how to use software more securely
71
Asymmetric encryption
Systems where different keys are used to encrypt and decrypt
72
Attack
An actual attempt at causing harm to a system
73
Attack surface
It's the sum of all the different attack vectors in a given system
74
Attack vector
Method or mechanism by which an attacker or malware gains access to a network or system
75
Auditing
It involves reviewing records to ensure that nothing is out of the ordinary
76
Authentication
A crucial application for cryptographic hash functions
77
Authentication server (AS)
It includes the user ID of the authenticating user
78
Authorization
It pertains to describing what the user account has access to or doesn't have access to
79
Availability
Means that the information we have is readily accessible to those people that should have it
80
Backdoor
A way to get into a system if the other methods to get in a system aren't allowed, it's a secret entryway for attackers
81
Baiting
An attack that happens through actual physical contact, enticing a victim to do something
82
Bastion hosts or networks
A server used to provide access to a private network from an external network
83
Binary whitelisting software
It's a list of known good and trusted software and only things that are on the list are permitted to run
84
Biometric authentication
Authentication that uses Biometric data
85
Bind
It is how clients authenticate to the server
86
Botnet
A collection of one or more Bots
87
Bots
Machines compromised by malware that are utilized to perform tasks centrally controlled by an attacker
88
Block ciphers
The cipher takes data in, places that into a bucket or block of data that's a fixed size, then encodes that entire block as one unit
89
Brute force attacks
A common password attack which consists of just continuously trying different combinations of characters and letters until one gets access
90
CA (Certificate authority)
It's the entity that's responsible for storing, issuing, and signing certificates. It's a crucial component of the PKI system
91
Caesar cipher
A substitution alphabet, where you replace characters in the alphabet with others usually by shifting or rotating the alphabet, a set of numbers or characters
92
CBC-MAC (Cipher block chaining message authentication codes)
A mechanism for building MACs using block ciphers
93
CCMP (counter mode CBC-MAC protocol)
A mode of operation for block ciphers that allows for authenticated encryption
94
Central repository
It is needed to securely store and index keys and a certificate management system of some sort makes managing access to storage certificates and issuance of certificates easier
95
Certificate-based authentication
It is the most secure option, but it requires more support and management overhead since every client must have a certificate
96
Certificate fingerprints
These are just hash digests of the whole certificate, and aren't actually fields in the certificate itself, but are computed by clients when validating or inspecting certificates
97
Certificate Revocation List (CRL)
A means to distribute a list of certificates that are no longer valid
98
Certificate Signature Algorithm
This field indicates what public key algorithm is used for the public key and what hashing algorithm is used to sign the certificate
99
Certificate Signature Value
The digital signature data itself
100
CIA Triad
Confidentiality, integrity, and availability. Three key principles of a guiding model for designing information security policies
101
Client certificates
They operate very similarly to server certificates but are presented by clients and allow servers to authenticate and verify clients
102
CMACs (Cipher-based Message Authentication Codes)
The process is similar to HMAC, but instead of using a hashing function to produce a digest, a symmetric cipher with a shared keys used to encrypt the message and the resulting output is used as the MAC
103
Code signing certificates
It is used for signing executable programs and allows users of these signed applications to verify the signatures and ensure that the application was not tampered with
104
Confidentiality
Keeping things hidden
105
Correlation analysis
The process of taking log data from different systems, and matching events across the systems
106
Counter-based tokens
They use a secret seed value along with the secret counter value that's incremented every time a one-time password is generated on the device
107
Cross-site scripting (XSS)
A type of injection attack where the attacker can insert malicious code and target the user of the service
108
Cryptanalysis
Looking for hidden messages or trying to decipher coded message
109
Cryptographic hashing
It is distinctly different from encryption because cryptographic hash functions should be one directional
110
Cryptography
The overarching discipline that covers the practice of coding and hiding messages from third parties
111
Cryptology
The study of cryptography
112
Cryptosystem
A collection of algorithms for key generation and encryption and decryption operations that comprise a cryptographic service
113
Data binding and sealing
It involves using the secret key to derive a unique key that's then used for encryption of data
114
Data exfiltration
The unauthorized transfer of data from a computer. It's also a very important concern when a security incident happens
115
Data handling policies
Should cover the details of how different data is classified
116
Data information tree
A structure where objects will have one parent and can have one or more children that belong to the parent object
117
Decryption
The reverse process from encryption; taking the garbled output and transforming it back into the readable plain text
118
Defense in depth
The concept of having multiple overlapping systems of defense to protect IT systems
119
Denial-of-Service (DoS) attack
An attack that tries to prevent access to a service for legitimate users by overwhelming the network or server
120
DES (Data Encryption Standard)
One of the earliest encryption standards
121
Deterministic
It means that the same input value should always return the same hash value
122
DH (Diffie-Hellman)
A popular key exchange algorithm, named for its co-inventors
123
Dictionary attack
A type of password attack that tries out words that are commonly used in passwords, like password, monkey, football
124
Distinguished name (DN)
A unique identifier for each entry in the directory
125
Distributed Denial-of-Service (DDoS) attack
A DoS attack using multiple systems
126
DNS Cache Poisoning Attack
It works by tricking a DNS server into accepting a fake DNS record that will point you to a compromised DNS server
127
DSA (Digital Signature Algorithm)
It is another example of an asymmetric encryption system, though its used for signing and verifying data
128
Dynamic ARP inspection (DAI)
A feature on enterprise switches that prevents certain types of attacks
129
EAP-TLS
One of the more common and secure EAP methods
130
ECDH & ECDSA
Elliptic curve variants of Diffie-Hellman and DSA, respectively
131
Eliptic curve cryptography (ECC)
A public key encryption system that uses the algebraic structure of elliptic curves over finite fields to generate secure keys
132
Encapsulating security payload
It's a part of the IPsec suite of protocols, which encapsulates IP packets, providing confidentiality, integrity, and authentication of the packets
133
Encryption
The act of taking a message (plaintext), and applying an operation to it (cipher), so that you receive a garbled, unreadable message as the output (ciphertext)
134
Encryption algorithm
The underlying logic or process that's used to convert the plaintext into ciphertext
135
End-entity (leaf certificate)
A certificate that has no authority as a CA
136
Entropy pool
A source of random data to help seed random number generators
137
Entry point
the act to determine the entry point to figure out how the attacker got in, or what vulnerability the malware exploited
138
Evil twin
The premise of an evil twin attack is for you to connect to a network that is identical to yours but that is controlled by an attacker. Once connected to it, they will be able to monitor your traffic
139
Exploit
Software that is used to take advantage of a security bug or vulnerability
140
Extensible authentication protocol (EAP over LAN, or EAPOL)
A standard authentication protocol
141
Fail to ban
A common open source flood guard protection tool
142
File-based encryption
Guarantees confidentiality and integrity of files protected by encryption
143
FIPS (Federal Information Processing Standard)
The DES that was adopted as a federal standard for encrypting and securing government data
144
Flood guards
Provide protection against DoS or Denial of Service Attacks
145
Forward secrecy
This is a property of a cryptographic system so that even in the event that the private key is compromised, the session keys are still safe
146
Four-Way Handshake
It is designed to allow an AP to confirm that the client has the correct pairwise master key in a WPA-PSK setup without disclosing the PMK
147
Frequency analysis
The practice of studying the frequency with which letters appear in ciphertext
148
Full disk encryption (FDE)
It is the practice of encrypting the entire drive in the system
149
GTK (Groupwise Transient Key)
A temporal key, which is actually used to encrypt data
150
Hacker
Someone who attempts to break into or exploit a system
151
Half-open attacks
A way to refer to SYN floods
152
Hash collisions
Two different inputs mapping to the same output
153
Hashing (Hash function)
A type of function or operation that takes in an arbitrary data input and maps it to an output of a fixed size, called a hash or a digest
154
High value data
usually includes account information, like usernames and passwords. Typically, any kind of user data is considered high value, especially if payment processing is involved
155
HMAC (Keyed-Hash Message Authentication Codes)
It uses a cryptographic hash function along with a secret key to generate a MAC
156
Host-based firewalls
Protects individual hosts from being compromised when they're used in untrusted and potentially malicious environments
157
HTTPS
It is the secure version of HTTP, the Hypertext Transfer Protocol
158
Hubs
Devices that serve as a central location through which data travels through; a quick and dirty way of getting packets mirrored to your capture interface
159
Identification
The idea of describing an entity uniquely
160
Impact
The impact of an incident is also an important issue to consider
161
Implicit deny
A network security concept where anything not explicitly permitted or allowed should be denied
162
Injection attacks
A common security exploit that can occur in software development and runs rampant on the web, where an attacker injects malicious code
163
Integrity
Means keeping our data accurate and untampered with
164
Intermediary (subordinate) CA
It means that the entity that this certificate was issued to can now sign other certificates
165
Intrusion detection and intrusion protection systems (IDS/IPS)
Operates by monitoring network traffic and analyzing it
166
IPsec (Internet Protocol security)
A VPN protocol that was designed in conjunction with IPv6
167
IP source guard (IPSG)
It can be enabled on enterprise switches along with DHCP snooping
168
Issuer Name
This field contains information about the authority that signed the certificate
169
Kerberos
A network authentication protocol that uses tickets to allow entities to prove their identity over potentially insecure channels to provide mutual authentication
170
Kerckhoff's principle
A principle that states that a cryptosystem, or a collection of algorithms for key generation and encryption and decryption operations that comprise a cryptographic service should remain secure, even if everything about the system is known except for the key
171
Key
A crucial component of a cipher, which introduces something unique into your cipher
172
Key escrow
Allows encryption key to be securely stored for later retrieval by an authorized party
173
Key length
It defines the maximum potential strength of the system
174
Key signing parties
Organized by people who are interested in establishing a web of trust, and participants perform the same verification and signing
175
Key size
It is the total number of bits or data that comprises the encryption key
176
Keylogger
A common type of spyware that's used to record every keystroke you make
177
Lightweight Directory Access Protocol (LDAP)
An open industry-standard protocol for accessing and maintaining directory services
178
Logic bomb
A type of Malware that's intentionally installed
179
Logs analysis systems
They are configured using user-defined rules to match interesting or atypical log entries
180
L2TP (Layer 2 Tunneling Protocol)
It is typically used to support VPNs
181
MACs (Message Authentication Codes)
A bit of information that allows authentication of a received message, ensuring that the message came from the alleged sender and not a third party masquerading as them
182
Malware
A type of malicious software that can be used to obtain your sensitive information or delete or modify files
183
MD5
A popular and widely used hash function designed in the early 1990s as a cryptographic hashing function
184
Meddler in the middle (formerly known as Man in the Middle)
An attack that places the attacker in the middle of two hosts that think they're communicating directly with each other
185
MIC (Message Integrity Check)
It is essentially a hash digest of the message in question
186
Monitor mode
It allows to scan across channels to see all wireless traffic being sent by APs and clients
187
Multifactor authentication (MFA)
A system where users are authenticated by presenting multiple pieces of information or objects
188
Network hardening
Is the process of securing a network by reducing its potential vulnerabilities through configuration changes, and taking specific steps
189
Network separation (network segmentation)
A good security principle for an IT support specialists to implement. It permits more flexible management of the network, and provides some security benefits. This is the concept of using VLANs to create virtual networks for different device classes or types
190
Network software hardening
Includes things like firewalls, proxies, and VPNs
191
Network time protocol (NTP)
A network protocol used to synchronize the time between the authenticator token and the authentication server
192
NIST
National Institute of Standards and Technology
193
Normalization
It's the process of taking log data in different formats and converting it into a standardized format that's consistent with a defined log structure
194
OAuth
An open standard that allows users to grant third-party websites and applications access to their information without sharing account credentials
195
One-time password (OTP)
A short-lived token, typically a number that's entered along with a username and password
196
One-time password (OTP) tokens
Another very common method for handling multifactor
197
OpenID
An open standard that allows participating sites known as Relying Parties to allow authentication of users utilizing a third party authentication service
198
Organizational units (OUs)
Folders that let us group related objects into units like people or groups to distinguish between individual user accounts and groups that accounts can belong to
199
Packet sniffing (packet capture)
the process of intercepting network packets in their entirety for analysis
200
Pairwise Transient Key (PTK)
It is generated using the PMK, AP nonce, Client nonce, AP MAC address, and Client MAC address
201
Password attacks
Utilize software like password crackers that try and guess your password
202
Password salt
Additional randomized data that's added into the hashing function to generate the hash that's unique to the password and salt combination
203
PBKDF2 (Password Based Key Derivation Function 2)
Password Based Key Derivation Function 2
204
PCI DSS
Payment Card Industry Data Security Standard
205
Penetration testing
The practice of attempting to break into a system or network to verify the systems in place
206
PGP (Pretty Good Privacy) encryption
An encryption application that allows authentication of data along with privacy from third parties relying upon asymmetric encryption to achieve this
207
Phishing attack
It usually occurs when a malicious email is sent to a victim disguised as something legitimate
208
Physical tokens
They take a few different forms, such as a USB device with a secret token on it, a standalone device which generates a token, or even a simple key used with a traditional lock
209
PIN authentication method
It uses PINs that are eight-digits long, but the last digit is a checksum that's computed from the first seven digits
210
Ping flood
It sends tons of ping packets to a system. If a computer can't keep up with this, then it's prone to being overwhelmed and taken down
211
PKI system
A system that defines the creation, storage and distribution of digital certificates
212
Platform key
It's the public key corresponding to the private key used to sign the boot files
213
Port mirroring
Allows the switch to take all packets from a specified port, port range, or the entire VLAN and mirror the packets to a specified switch port
214
Pre-shared key
It's the Wi-Fi password you share with people when they come over and want to use your wireless network
215
Principle of least privilege
Helps to ensure that sensitive data is only accessed by people who are authorized to access it
216
Privacy policies
Oversees the access and use of sensitive data
217
Promiscuous mode
A type of computer networking operational mode in which all network data packets can be accessed and viewed by all network adapters operating in this mode
218
Proxy:
Can be useful to protect client devices and their traffic. They also provide secure remote access without using a VPN
219
Pseudo-random
Something that isn't truly random
220
Public key authentication
A key pair is generated by the user who wants to authenticate
221
Public key signatures
Digital signature generated by composing the message and combining it with the private key
222
RA (Registration Authority)
It is responsible for verifying the identities of any entities requesting certificates to be signed and stored with the CA
223
Rainbow table attacks
To trade computational power for disk space by pre-computing the hashes and storing them in a table
224
Rainbow tables
A pre-computed table of all possible password values and their corresponding hashes
225
Random numbers
A very important concept in encryption because it avoids some kind of pattern that an adversary can discover through close observation and analysis of encrypted messages over time
226
Ransomware
A type of attack that holds your data or system hostage until you pay some sort of ransom
227
RC4 (Rivest Cipher 4)
Asymmetric stream cipher that gained widespread adoption because of its simplicity and speed
228
Recoverability
How complicated and time-consuming the recovery effort will be
229
Remote attestation
The idea of a system authenticating its software and hardware configuration to a remote system
230
Remote Authentication Dial-in User Service (RADIUS)
A protocol that provides AAA services for users on a network
231
Reverse proxy
A service that might appear to be a single server to external clients, but actually represents many servers living behind it
232
Risk
The possibility of suffering a loss in the event of an attack on the system
233
Risk mitigation
Understanding the risks your systems face, take measures to reduce those risks, and monitor them
234
Rogue Access Point (AP) Attack
An access point that is installed on the network without the network administrator's knowledge
235
Rogue DHCP server attack
An attacker can hand out DHCP leases with whatever information they want by deploying a rogue DHCP server on your network, setting a gateway address or DNS server, that's actually a machine within their control
236
Root certificate authority
They are self signed because they are the start of the chain of trust, so there's no higher authority that can sign on their behalf
237
Rootkit:
A collection of software or tools that an admin would use
238
RSA
One of the first practical asymmetric cryptography systems to be developed, named for the initials of the three co-inventors: Ron Rivest, Adi Shamir and Leonard Adleman
239
Screen lock
A security feature that helps prevent unwanted access by creating an action you have to do to gain entry
240
Secure boot protocol
It uses public key cryptography to secure the encrypted elements of the boot process
241
Secure channel
It is provided by IPsec, which provides confidentiality, integrity, and authentication of data being passed
242
Secure element
It's a tamper resistant chip often embedded in the microprocessor or integrated into the mainboard of a mobile device
243
Secure Shell (SSH)
A secure network protocol that uses encryption to allow access to a network service over unsecured networks
244
Security
It's all about determining risks or exposure understanding the likelihood of attacks; and designing defenses around these risks to minimize the impact of an attack
245
Security information and event management systems (SIEMS)
Form of centralized logging for security administration purposes
246
Security keys
Small embedded cryptoprocessors, that have secure storage of asymmetric keys and additional slots to run embedded code
247
Security through obscurity
The principle that if no one knows what algorithm is being used or general security practices, then one is safe from attackers
248
Seed value
A secret value that is used to initialize a process that is generated by software using one or more values
249
Self-signed certificate
This certificate has been signed by the same entity that issued the certificate
250
Serial number
A unique identifier for their certificate assigned by the CA which allows the CA to manage and identify individual certificates
251
Session hijacking (cookie hijacking)
A common meddler in the middle attack
252
Session key
The shared symmetric encryption key using TLS sessions to encrypt data being sent back and forth
253
Severity
Includes factors like what and how many systems were compromised and how the breach affects business functions
254
SHA1
It is part of the secure hash algorithm suite of functions, designed by the NSA and published in 1995
255
Shannon's maxim
It states that the system should remain secure, even if your adversary knows exactly what kind of encryption systems you're employing, as long as your keys remain secure
256
Single Sign-on (SSO)
An authentication concept that allows users to authenticate once to be granted access to a lot of different services and applications
257
Social engineering
An attack method that relies heavily on interactions with humans instead of computers
258
Software signing certificate
Trust mechanism where a software vendor can cryptographically sign binaries they distribute using a private key
259
Spear phishing
Phishing that targets individual or group - the fake emails may contain some personal information like your name, or the names of friends or family
260
Spoofing
When a source is masquerading around as something else
261
Spyware
The type of malware that's meant to spy on you
262
SQL Injection Attack
An attack that targets the entire website if the website is using a SQL database
263
SSL 3.0
The latest revision of SSL that was deprecated in 2015
264
SSL/TLS Client Certificate
Certificates that are bound to clients and are used to authenticate the client to the server, allowing access control to a SSL/TLS service
265
SSL/TLS Server Certificate
A certificate that a web server presents to a client as part of the initial secure setup of an SSL, TLS connection
266
StartTLS
It permits a client to communicate using LDAP v3 over TLS
267
Steganography
The practice of hiding information from observers, but not encoding it
268
Stream ciphers
It takes a stream of input and encrypts the stream one character or one digit at a time, outputting one encrypted character or digit at a time
269
Subject:
This field contains identifying information about the entity the certificate was issued to
270
Subject Public Key Info
These two subfields define the algorithm of the public key along with the public key itself
271
Substitution cipher
An encryption mechanism that replaces parts of your plaintext with ciphertext
272
Symmetric key algorithm
Encryption algorithms that use the same key to encrypt and decrypt messages
273
SYN flood
The server is bombarded with SYN packets
274
TACACS+
It is a device access AAA system that manages who has access to your network devices and what they do on them
275
Tailgating
Gaining access into a restricted area or building by following a real employee in
276
Tcpdump
It's a super popular, lightweight command-line based utility that you can use to capture and analyze packets
277
Threat
The possibility of danger that could exploit a vulnerability
278
Threats & password policies
Protects Data & IP, Data Protection, Infrastructure Defense, Identity Management, and users
279
Ticket granting service (TGS)
It decrypts the Ticket Granting Ticket using the Ticket Granting Service secret key, which provides the Ticket Granting Service with the client Ticket Granting Service session key
280
Time-based token (TOTP)
A One-Time-Password that's rotated periodically
281
TKIP (Temporal Key Integrity Protocol):
To address the shortcomings of WEP security
282
TLS 1.2
The current recommended revision of SSL
283
TLS 1.2 with AES GCM
A specific mode of operation for the AES block cipher that essentially turns it into a stream cipher
284
TLS Handshake
A mechanism to initially establish a channel for an application to communicate with a service
285
TPM (Trusted Platform Module)
This is a hardware device that's typically integrated into the hardware of a computer, that's a dedicated crypto processor
286
Transport mode
One of the two modes of operations supported by IPsec. When used, only the payload of the IP packet is encrypted, leaving the IP headers untouched
287
Trojan
malware that disguises itself as one thing but does something else
288
Trusted execution environment (TEE)
It provides a full-blown isolated execution environment that runs alongside the main OS
289
Tunnel
It is provided by L2TP, which permits the passing of unmodified packets from one network to another
290
Tunnel mode
One of the two modes of operations supported by IPsec. When used, the entire IP packet, header, payload, and all, is encrypted and encapsulated inside a new IP packet with new headers
291
Unbind
It closes the connection to the LDAP server
292
Username and password authentication
Can be used in conjunction with certificate authentication, providing additional layers of security
293
U2F (Universal 2nd Factor)
It's a standard developed jointly by Google, Yubico and NXP Semiconductors that incorporates a challenge-response mechanism, along with public key cryptography to implement a more secure and more convenient second-factor authentication solution
294
Validity
This field contains two subfields, Not Before and Not After, which define the dates when the certificate is valid for
295
Vendor risk review
Questionnaire that covers different aspects of their security policies procedures and defenses
296
Version
What version of the X.509 standard certificate adheres to
297
Viruses
The best known type of malware
298
VPN (Virtual Private Network)
A secure method of connecting a device to a private network over the internet
299
VPNs
Commonly used to provide secure remote access, and link two networks securely
300
Vulnerability
A flaw in the system that could be exploited to compromise the system
301
Vulnerability scanner
Detect lots of things, ranging from misconfigured services that represent potential risks, to detecting the presence of back doors and systems
302
Web of trust
It is where individuals instead of certificate authorities sign other individuals' public keys
303
WEP (Wired Equivalent Privacy)
First security protocol introduced for Wi-FI networks
304
Wireshark
It's another packet capture and analysis tool that you can use, but it's way more powerful when it comes to application and packet analysis, compared to tcpdump
305
Worms
They are similar to viruses except that instead of having to attach themselves onto something to spread, worms can live on their own and spread through channels like the network
306
WPA (Wi-fi protected access)
Designed as a short-term replacement that would be compatible with older WEP-enabled hardware with a simple firmware update
307
WPA2 Enterprise
It's an 802.1x authentication to Wi-Fi networks
308
WPS (Wifi Protected Setup)
It's a convenience feature designed to make it easier for clients to join a WPA-PSK protected network
309
X.509 standard
It is what defines the format of digital certificates, as well as a certificate revocation list or CRL
310
XTACACS
It stands for Extended TACACS, which was a Cisco proprietary extension on top of TACACS
311
0-Day Vulnerability (Zero Day)
A vulnerability that is not known to the software developer or vendor, but is known to an attacker
312
404 Not Found
An error message you might see on websites that have been moved or deleted
313
AAA (authentication, authorization, accounting)
The services that the directory services provide to all the computers within a company or organization
314
Abstraction
To take a relatively complex system and simplify it for our use
315
Absolute path
It is one that starts from the main directory
316
ACI
Access Control Lists
317
ACK flag
One of the TCP control flags. ACK is short for acknowledge. A value of one in this field means that the acknowledgment number field should be examined
318
Acknowledgement number
The number of the next expected segment in a TCP sequence
319
Active directory (AD)
The Microsoft alternative to directory services that offers customization and added features for the Windows platform
320
Active directory users and computers (ADUC)
The client tools that are used for accessing and administering a directory server
321
Address bus
Connects the CPU to the MCC and sends over the location of the data, but not the data itself
322
Address class system
A system which defines how the global IP address space is split up
323
Address Resolution Protocol (ARP)
A protocol used to discover the hardware address of a node with a certain IP address
324
Ad-Hoc network
A network configuration without supporting network infrastructure. Every device involved with the ad-hoc network communicates with every other device within range, and all nodes help pass along messages
325
Administrator
A user that has complete control over a machine
326
Advanced group policy management (AGPM)
A set of add-on tools from Microsoft that gives some added provision control abilities in GPMC
327
Algorithm
A series of steps that solves specific problems
328
Alias
A nickname for common commands
329
Android
A mobile operating system based on Linux
330
Anycast
A technique that's used to route traffic to different destinations depending on factors like location, congestion, or link health
331
Appending flags
A way to add the data of the file without erasing existing data
332
Application
A computer program designed for a specific use
333
Application layer
The layer that allows network applications to communicate in a way they understand
334
Application layer payload
The entire contents of whatever data applications want to send to each other
335
Application software
Any software created to fulfill a specific need, like a text editor, web browser, or graphics editor
336
App store apps
A Package Manager that acts as a repository
337
App store repository
A app store service that also acts as a repository
338
App stores
A central managed marketplace for app developers to publish and sell mobile apps
339
APPX
An APPX is another way to package contents of a file to act like a unit of distribution
340
Archive
An archive is comprised of one or more files that are compressed into a single file" for verb agreement
341
A record:
The most common resource record, used to point a certain domain name at a certain IPv4 IP address
342
ARPANET
The earliest version of the Internet that we see today, created by the US government project DARPA in the 1960s
343
ARP table
A list of IP addresses and the MAC addresses associated with them
344
ASCII
The oldest character encoding standard used is ASCII. It represents the English alphabet, digits, and punctuation marks
345
ASN
Autonomous System Number is a number assigned to an individual autonomous system
346
Assembly language
A language that allowed computer scientists to use human readable instructions, assembled into code that the machines could understand
347
Asymmetric Digital Subscriber Line (ADSL)
A device that establishes data connections across phone lines and different speeds for uploading and downloading data
348
ATA
The most common interface that hard drives use to connect to our system
349
ATX (Advanced Technology eXtended)
The most common form factor for motherboards
350
Automatic allocation
A range of IP addresses is set aside for assignment purposes
351
Automation
It makes processes work automatically
352
Autoscaling
A system that allows the service to increase or reduce capacity as needed, while the service owner only pays for the cost of the machines that are in use at any given time
353
Background processes/Daemon processes
Processes that run or take place in the background
354
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
355
Backward compatible
It means older hardware works with newer hardware
356
Bash
The language used to interact with the shell
357
Baud rate
A measurement of how many bits could be passed across a phone line in a second
358
Binary system
The communication that a computer uses is referred to as binary system, also known as base-2 numeral system
359
Bind operation
The operation which authenticates clients to the directory server
360
Biometric data
A way of protecting your accounts and information using biometric data such as facial recognition and fingerprint
361
BIOS/UEFI
A low-level software that initializes our computer's hardware to make sure everything is good to go
362
Bios (Basic Input Output Services)
The BIOS is software that helps initialize the hardware in our computer and gets our operating system up and running
363
Block ciphers
The cipher takes data in, places that into a bucket or block of data that's a fixed size, then encodes that entire block as one unit
364
Block devices
A system that acts like USB drives and hard drive by transmitting data
365
Block storage
It improves faster handling of data because the data isn't stored in one long piece but in blocks, so it can be accessed more quickly
366
Bluetooth
The most common short range wireless network
367
Boot
To start up a computer
368
Bootloader
A small program that loads the operating system
369
Botnet
A collection of one or more Bots
370
Bots
Machines compromised by malware that are utilized to perform tasks centrally controlled by an attacker
371
Broadband
Any connectivity technology that isn't dial-up Internet
372
Browser
A user interface for displaying and interacting with web pages
373
BYOD (Bring Your Own Device)
Refers to the practice of allowing people to use their own personal devices for work
374
Byte
A group of 8 bits
375
Cable modem
A device that sits at the edge of a consumer's network and connects it to the cable modem termination system
376
Cable modem termination system
Connects lots of different cable connections to an ISP's core network
377
Cache
The assigned stored location for recently or frequently accessed data; on a mobile app it is where anything that was changed or created with that app is stored
378
Caching and recursive name servers
They are generally provided by an ISP or your local network, and their purpose is to store domain name lookups for a certain amount of time
379
Centralized logging
Parsing logs in one central location
380
Central management
A central service that provides instructions to all of the different parts of my IT infrastructure
381
Change management process
The process to notify others in the organization about the changes that you are about to make
382
Channels
Individual, smaller sections of the overall frequency band used by a wireless network
383
Character devices
A way to transmit data character by character like a keyboard and mouse
384
Character encoding
Is used to assign our binary values to characters so that we as humans can read them
385
Charge cycle
One full charge and discharge of a battery
386
Child directories
It is a directory housed by a parent directory
387
Children's Online Privacy Protection Act (COPPA)
Regulates the information we show to children under the age of 13
388
Chipset
It decides how components talk to each other on our machine
389
Chocolatey
A third party package manager for Windows
390
Chrome OS
A Linux-based operating system designed by Google
391
CLI
Command line interpreter
392
Client/Server runtime subsystem
System that handles running Windows GUI and Command line
393
Clock cycle
When you send a voltage to the clock wire
394
Clock speed:
The maximum number of clock cycles that it can handle in a set in a certain time period
395
Clock wire
When you send or receive data, it sends a voltage to that clock wire to let the CPU know it can start doing calculations
396
CLOSE_WAIT
A connection state that indicates that the connection has been closed at the TCP layer, but that the application that opened the socket hasn't released its hold on the socket yet
397
CLOSE
A connection state that indicates that the connection has been fully terminated, and that no further communication is possible
398
Closed source packages
A source code that does not allow public access
399
Cloud computing
The concept and technological approach of accessing data, using applications, storing files, etc. from anywhere in the world as long as you have an internet connection
400
Cloud computing
The concept and technological approach of accessing data, using applications, storing files, etc. from anywhere in the world as long as you have an internet connection
401
CNAME
A resource record used to map one domain to another
402
Coding
Translating one language to another
403
Command line
A text interface program for a computer that inputs text commands and translates them to the operating system
404
Command Line Interface (CLI)
A shell that uses text commands to interact with the operating system
405
Command line mode
When you are able to run commands while still in your current shell
406
Compiled programming language
A language that uses human readable instructions, then sends them through a compiler
407
Computer
A device that stores and processes data by performing calculations
408
Computer configuration
Contained within a Group Policy Object (GPO)
409
Computer file
Data that we store and a file can be anything, a word document, a picture, a song, literally anything
410
Computer management
A tool that lets you manage a local or remote computer
411
Configuration management
The creation of rules about how things should work in your organization, such as printers, configure software, or mounting network file systems
412
Connectionless protocol
A data-transmission protocol that allows data to be exchanged without an established connection at the transport layer. The most common of these is known as UDP, or User Datagram Protocol
413
Connection-oriented protocol
A data-transmission protocol that establishes a connection at the transport layer, and uses this to ensure that all data has been properly transmitted
414
Copyright
Used when creating original work
415
CPU
Central processing unit
416
CPU sockets
A CPU socket is a series of pins that connect a CPU’s processor to the PC’s motherboard
417
DACL
Directory Control Lists
418
DARPA
A US government project in the 1960s that went on to create the earliest version of the Internet that we see today
419
Data
Actual content of a file
420
Databases
Databases allow us to store query, filter, and manage large amounts of data
421
Data blocks
Data that can be broken down into many pieces and written to different parts of the hard disk
422
Data buffer
A region of RAM that’s used to temporarily store data while it’s being moved around
423
Data center
A facility that stores hundreds, if not thousands of servers
424
Data offset field
The number of the next expected segment in a TCP packet/datagram
425
Data payload section
Has all of the data of the protocols further up the stack of a frame
426
Data recovery
Is the process of trying to restore data after an unexpected event that results in data loss or corruption
427
Data sizes
Metrics that refer to data sizes including bit, byte, kilobyte, kibibyte, and megabyte
428
Data tapes
The standard medium for archival backup data storage
429
DDR SDRAM (Double Data Rate SDRAM)
A type of RAM that is faster, takes up less power, and has a larger capacity than earlier SDRAM versions
430
Debian(.deb)
A Debian package is packaged as a .deb file
431
Decimal form- base 10 system
In the decimal system, there are 10 possible numbers you can use ranging from zero to nine
432
Default domain control policy
One of the two GPOs that are created when a new Active Directory domain has been made
433
Defragmentation
A process of taking all the files stored on a given disk and reorganizing them into neighboring locations
434
Delegation
The administrative tasks that you need to perform a lot as a part of your day to day job but you don't need to have broad access to make changes in AD
435
Demarcate
To set the boundaries of something
436
Demarcation point
Where one network or system ends and another one begins
437
Demultiplexing
Taking traffic that's all aimed at the same node and delivering it to the proper receiving service
438
Deployment
Hardware is set up so that the employee can do their job
439
Desktop
The main screen where we can navigate our files, folders, and applications
440
Destination network
The column in a routing table that contains a row for each network that the router knows about
441
Destination port
The port of the service the TCP packet is intended for
442
Detection measure
The measures to alert you and your team that a disaster has occurred that can impact operations
443
Device manager
A console management system for your device
444
DHCP
A technology that assigns an IP address automatically to a new device. It is an application layer protocol that automates the configuration process of hosts on a network
445
DHCP discovery
The process by which a client configured to use DHCP attempts to get network configuration information
446
Dial-up
Uses POTS for data transfer, and gets its name because the connection is established by actually dialing a phone number
447
Differential backup
A backup of files that are changed, or has been created since the last full backup
448
Digital divide
The growing skills gap between people with and without digital literacy skills
449
DIMM
Dual Inline Memory Module
450
Directory Access Protocol (DAP)
A protocol that is included in the X.500 directory standard from 1988
451
Directory Information Shadow Protocol (DISP)
A protocol that is included in the X.500 directory standard from 1988
452
Directory Operational Bindings Protocol (DOBMP)
A protocol that is included in the X.500 directory standard from 1988
453
Directory server
The server that contains a lookup service that provides mapping between network resources and their network addresses
454
Directory services
A lookup service contained in a network server that provides mapping between network resources and their network addresses
455
Directory System Protocol (DSP)
A protocol that is included in the X.500 directory standard from 1988
456
Disaster recovery plan:
A collection of documented procedures and plans on how to react and handle an emergency or disaster scenario, from the operational perspective
457
Disaster recovery testing
A regular exercise that happens once a year or so, that has different teams, including IT support specialists, going through simulations of disaster events
458
Disk Management utility
Native tool for Windows that helps with managing disk space
459
Disk to disk cloning
A type of cloning that happens when you connect an external hard drive to the machine you want to clone
460
Display port
Port which also outputs audio and video
461
Distribution
A version of the operating system
462
Distribution group
A group that is only designed to group accounts and contacts for email communication
463
Distributions
Some common Linux distributions are Ubuntu, Debian, and Red Hat
464
DNS records
A DNS request for the SRV records matching the domain that it's been bound to
465
DNS zones
A portion of space in the Domain Name System (DNS) that is controlled by an authoritative name server
466
Domain
Used to demarcate where control moves from a top-level domain name server to an authoritative name server
467
Domain admin
The administrators of the Active Directory domain
468
Domain computers
All the computers joined to the domain except domain controllers
469
Domain controllers (DC)
The service that hosts copies of the Active Directory database
470
Domain local
The tool used used to assign permission to a resource
471
Domain name
A website name; the part of the URL following www.
472
Domain Name System (DNS)
A global and highly distributed network service that resolves strings of letters, such as a website name, into an IP address
473
Domain users
A group that contains every user account in the domain
474
Dotted decimal notation
A format of using dots to separate numbers in a string, such as in an IP address
475
DRAM
Dynamic Random Access Memory
476
Driver
Used to help our hardware devices interact with our Operating System
477
Drivers
The drivers contain the instructions our CPU needs to understand external devices like keyboards, webcams, printers
478
DSL
Digital subscriber line was able to send much more data across the wire than traditional dial-up technologies by operating at a frequency range that didn't interfere with normal phone calls
479
DSLAM
Digital Subscriber Line Access Multiplexers are devices that connect multiple DSL connections to a high-speed digital communications channel
480
Duration field
Specifies how long the total frame is
481
DVI
DVI cables generally just output video
482
Dynamic allocation
A range of IP addresses is set aside for client devices and one of these IPs is issued to these devices when they request one
483
Dynamic IP address
An IP address assigned automatically to a new device through a technology known as Dynamic Host Configuration Protocol
484
Dynamic-link libraries
Programs that want to use functionality that the code provides can tap into it if they need to (shared libraries)
485
.exe
A file extension found in Windows for an executable file
486
Electrostatic discharge
Electrostatic discharge is a sudden and momentary flow of electric current between two electrically charged objects caused by contact, an electrical short or dielectric breakdown
487
Enterprise admin
The administrators of the Active Directory domain that has permission to make changes to the domain that affect other domains in a multi-domain forest
488
Enterprise app management
A management system that allows an organization to distribute custom mobile apps
489
Enterprise mobility management (EMM)
A system that can create and distribute policies and MDMs
490
Environment
Whatever settings or variables a child process inherits from the parent’s process
491
Error detection
The ability for a protocol or program to determine that something went wrong
492
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
492
DACL
Directory Control Lists
493
Error message
Helpful indicators that can point you in the right direction
494
Error recovery
The ability for a protocol or program to attempt to fix an error
495
Escape characters
A concept that means that the next character after the back tick should be treated literally
496
ESTABLISHED
Status indicating that the TCP connection is in working order, and both sides are free to send each other data
497
Etcher.io
A tool you can use to load an install image onto your USB device and make it bootable
498
Ethernet cable
It lets you physically connect to the network through a cable
499
Event Viewer
A place where all events that have been logged are stored
500
Executable file
A file containing instructions for a computer to execute when they’re run
501
Expansion slots
Give us the ability to increase the functionality of our computer
502
Exterior gateway
Protocols that are used for the exchange of information between independent autonomous systems
503
External Data Bus (EDB)
It's a row of wires that interconnect the parts of our computer
504
Factory reset
Resetting a device to the settings it came with from the factory
505
Fast logon optimization
The group policy engine that applies policy settings to a local machine may sacrifice the immediate application of some types of policies in order to make logon faster
506
File compression
The files and folder structures are copied and put into an archive
507
File extension
The appended part of a filename that tells us what type of file it is in certain operating systems
508
File handling
A process of storing data using a program
509
File permissions
A process for setting permissions for who has access to certain files
510
File record number
The index of the files entry in the MFT
511
File storage service
Allows to centrally store files and manage access between files and groups
512
File system
A system used to manage files
513
FIN_WAIT
A TCP socket state indicating that a FIN has been sent, but the corresponding ACK from the other end hasn't been received yet
514
FIN
One of the TCP control flags. FIN is short for finish. When this flag is set to one, it means the transmitting computer doesn't have any more data to send and the connection can be closed
515
Finder
The file manager for all Macs
516
Firewall
It is a device that blocks or allows traffic based on established rules
517
Firmware
Software that's permanently stored on a computer component
518
Fixed allocation
Requires a manually specified list of MAC address and the corresponding IPs
519
Flag field
It is used to indicate if a datagram is allowed to be fragmented, or to indicate that the datagram has already been fragmented
520
Flat file
A collection of records/information that follow a consistent format with rules around stored values. On a host computer, one use is to have a list of network address and host name pairs (a hosts file)
521
Flexible single-master operations (FSMO)
The single domain controller that has been tasked with making changes to the AD database that can only be made by one DC at a time
522
Flow label field
20-bit field that's used in conjunction with the traffic class field for routers to make decisions about the quality of service level for a specific datagram
523
Folders/Directories
Used to organize files
524
Forest
The hierarchy above a domain that contains multiple domains, allowing accounts to share resources between domains that are in the same forest
525
Form factor
A mathematical way to compensate for irregularities in the shape of an object by using a ratio between its volume and height
526
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
527
Fragmentation offset field
It contains values used by the receiving end to take all the parts of a fragmented packet and put them back together in the correct order
528
Frame control field
16 bits long, it contains a number of sub-fields that are used to describe how the frame itself should be processed
529
Frequency band
A certain section of the radio spectrum that's been agreed upon to be used for certain communications
530
FTP
An older method used for transferring files from one computer to another, but you still see it in use today
531
FTTB
Fiber to the building, fiber to the business or even fiber to the basement, since this is generally where cables to buildings physically enter. FTTB is a setup where fiber technologies are used for data delivery to an individual building
532
FTTH
Fiber to the home. This is used in instances where fiber is actually run to each individual residents in a neighborhood or apartment building
533
FTTN
Fiber to the neighborhood. This means that fiber technologies are used to deliver data to a single physical cabinet that serves a certain amount of the population
534
FTTP
Fiber to the premises. FTTH and FTTB may both also be referred to as FTTP
535
FTTX
Stands for fiber to the X, where the X can be one of many things
536
Full backup
The full unmodified contents of all files to be backed up is are included in this backup mechanism whether the data was modified or not
537
Full control
A user or group with full control that can do anything they want to files
538
Fully qualified domain name
When you combine all the parts of a domain together
539
Functional levels
The different versions of Active Directory, a functional level that describes the features that it supports
540
GIT
A version control system that helps keep track of changes made to files and directories
541
Global
The tool that is used to group accounts into a role
542
Globalization
The movement that lets governments, businesses, and organizations communicate and integrate together on an international scale
543
Group policy management console (GPMC)
The tools used for creating and viewing a group policy object
544
Group policy objects (GPO)
The ways to manage the configuration of Windows machines, referring to the objects that represent things in your network that you want to be able to reference or manage
545
Group policy settings reference
A spreadsheet that details the GPO policies and preferences that are available and where to find them
546
Groups
A collection of users
547
Group scope:
The way that group definitions are replicated across domains
548
GUI
graphical user interface
549
GUID partition table
Only used if you are using UEFI booting
550
Handshake
A way for two devices to ensure that they're speaking the same protocol and will be able to understand each other
551
Hard drive
It is a long term memory component that holds all of our data, which can include music, pictures, applications
552
Hard link
When created in NTFS, an entry is added to the MFT that points to the linked file record number, not the name of the file. This means the file name of the target can change and the hard link will still point to it
553
Hardware
External or internal devices and equipment that help you perform major functions
554
Hardware ID
A special string of characters assigned to hardware
555
Hardware resource deficiency
It refers to the lack of system resources like memory, hard drive space, et cetera
556
Having dependencies
A process of counting on other pieces of software to make an application work since one bit of code depends on another in order to work
557
HDD (Hard disk drive)
Hard disk drives, or HDDs, use a spinning platter and a mechanical arm to read and write information
558
HDMI
A type of cable that outputs both video and audio
559
HDSL
High Bit-rate Digital Subscriber Lines. These are DSL technologies that provision speeds above 1.544 megabits per second
560
Header checksum field
A checksum of the contents of the entire IP datagram header
561
Header length field
A four bit field that declares how long the entire header is. It is almost always 20 bytes in length when dealing with IPv4
562
Heatsink
It is used to dissipate heat from our CPU
563
HFS+/APFS
HFS+ is a journaling system developed by Apple Inc. and APFS is another but more encrypted Apple journaling system
564
Hidden files
A set of files that are not visible either to avoid alteration or simply because you don’t want someone to see them
565
Hop limit field
An 8-bit field that's identical in purpose to the TTL field in an IPv4 header
566
Host file
It is a flat file that contains, on each line, a network address followed by the host name it can be referred to as
567
Hostname
Used to identify the computer when it needs to talk to other computers
568
Hot key
A keyboard shortcut that does a particular task
569
HTTP status code
The codes or numbers that indicate some sort of error or info messages that occurred when trying to access a web resource
570
Hybrid cloud
Used to describe situations where companies might run things like their most sensitive proprietary technologies on a private cloud or on premise while entrusting their less sensitive servers to a public cloud
571
Hypervisor
A piece of software that runs and manages virtual machines while also
offering guests a virtual operating platform that's indistinguishable from actual hardware
572
I/O management
Anything that can give us input or that we can use for output of data
573
I/O Streams
An input stream handles data flowing into and out of a program
574
IANA
The Internet Assigned Numbers Authority, is a non-profit organization that helps manage things like IP address allocation
575
ICMP
Internet control message protocol is used by router or remote hosts to communicate error messages when network problems prevent delivery of IP packets
576
ICMP payload
Piece of the packet which lets the recipient of the message knows which of their transmissions caused the error being reported
577
Identification field
It is a 16-bit number that's used to group messages together
578
Import
Moving a backup of the test example policy to the production example policy
579
Information technology
The use of digital technology, like computers and the internet, to store and process data into useful information
580
Infrastructure as a Service (IaaS)
A subset of cloud computing where a network and servers are provided for customers to run their services
581
Inherit only
A permission group that means that a DACL will be inherited, but not applied to a container
582
Inode
A file structure for metadata and files
583
Input/Output device
A device that performs input and output, including monitors, keyboards, mice, hard disk drives, speakers, bluetooth headsets, webcams, and network adapters
584
Install image:
A downloadable operating system image used to install an operating system on a device
585
Installing from source
A process of installing from a source
586
Instantiation
The actual implementation of something defined elsewhere
587
Instruction set
A list of instructions that our CPU is able to run
588
Interactive mode
When the parted tool launches you into a separate program
589
Interface
For a router, the port where a router connects to a network. A router gives and receives data through its interfaces. These are also used as part of the routing table
590
Interior gateway
Interior gateway protocols are used by routers to share information within a single autonomous system
591
Internet
A worldwide system of interconnected networks
592
Internet Corporation for Assigned Names and Numbers (ICANN)
Where website names are registered
593
Internet of Things (IoT)
The concept that more and more devices are connected to the internet in a smarter fashion such as smart thermostats that turn off the air conditioner when you leave and turn it on when you come back
594
Internet Protocol version 4 (IPv4)
An address that consists of 32 bits separated into four groups
595
Internet Protocol version 6 (IPv6)
An address that consist of a 128 bits, four times the amount that IPv4 uses
596
Interpreted programming language
A language that isn't compiled ahead of time
597
Intranet
An internal network inside a company, accessible if you are on a company’s network
598
iOS
A mobile operating system developed by Apple Inc.
599
IP address
The most common protocol used in the network layer, used to helps us route information
600
IP datagram
A highly structured series of fields that are strictly defined
601
IP masquerading
The NAT obscures the sender's IP address from the receiver
602
IP options field
An optional field and is used to set special characteristics for datagrams primarily used for testing purposes
603
IPv6 tunnel
IPv6 tunnel servers on either end of a connection take incoming IPv6 traffic and encapsulate it within traditional IPv4 datagrams
604
IPv6 tunnel brokers
Companies that provide IPv6 tunneling endpoints for you, so you don't have to introduce additional equipment to your network
605
IT Infrastructure
The software, the hardware, network, and services required for an organization to operate in an enterprise IT environment
606
ITX (Information Technology eXtended)
A form factor for motherboards that is much smaller than ATX boards
607
Kernel
The main core of an operating system that creates processes, efficiently schedules them, and manages how processes are terminated
608
Kernel module
It extends the kernel's functionality so developers don't have to actually touch the Linux kernel
609
Keylogger
A common type of spyware that's used to record every keystroke you make
610
KVM Switch
Keyboard, video, & mouse switch that looks like a hub that you can connect multiple computers to and control using one keyboard, mouse, and monitor
611
L2TP (Layer 2 Tunneling Protocol)
It is typically used to support VPNs
612
Land Grid Array (LGA)
It is a type of CPU socket that stick out of the motherboard
613
LDAP data interchange format
The tool that allows you to authenticate, add, remove users, groups, computers and so on in a directory service
614
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
614
DACL
Directory Control Lists
614
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
614
Identification field
It is a 16-bit number that's used to group messages together
615
DACL
Directory Control Lists
615
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
615
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
616
Identification field
It is a 16-bit number that's used to group messages together
617
LDAP Entry
A collection of information that's used to describe something
618
LDIF files
A text file that lists attributes and values that describe something
619
Library
A way to package a bunch of useful code that someone else wrote
620
Lightning adaptor
One of the standard power, data and display connector types used in mobile devices
621
Linked
A GPO that all of the computers or users under a domain, site, or OU will have a policy applied
622
Link-local unicast address
Allow for local network segment communications and are configured based upon a host's MAC address
623
Linux OS
Linux is one of the largest an open source operating system used heavily in business infrastructure and in the consumer space
624
Listen
It means that a TCP socket is ready and listening for incoming connections
625
List folder contents
A command that will execute and list folder contents and is an alias for Read and Execute
626
Load balancer
Ensures that each VM receives a balanced number of queries
627
Logging
The act of creating log events
628
Logic gates
Allow transistors to do more complex tasks, like decide where to send electrical signals depending on logical conditions
629
Log rotation
A way for the OS to clean out log files to make room for new ones
630
Logs
Files that record system events on our computer
631
Loopback address
An IP address that always points to itself. This type of address is used to test internal pathing through the TCP/IP protocols
632
MAC address
A globally unique identifier attached to an individual network interface. It's a 48-bit number normally represented by six groupings of two hexadecimal numbers
633
MAC filtering
Access points are configured to only allow for connections from a specific set of MAC addresses belonging to devices you trust
634
Mac OS
Apple's operating system
635
Maintenance
Where software is updated and hardware issues are fixed if, and when, they occur
636
Manifest
A library used if an application needs to use a shared library
637
Master boot record (MBR)
a traditional partition table within a storage disk that lets you have volume sizes of 2 terabytes or less and is mostly used in the Windows OS
638
Master file table (MFT)
A way NTFS stores and represents the files you’re working with on your operating system
639
Mb/s
megabit per second, which is a unit of data transfer rate
640
MDM policy
The profiles that contains settings for the device
641
MDM profile
The policies that contains settings for the device
642
Memory controller chip (MCC)
A bridge between the CPU and the RAM
643
Memory management
One of the functions that a kernel performs; it optimizes memory usage and make sure our applications have enough memory to run
644
Memory manager
A Windows OS program that helps manage virtual memory
645
Memory usage
The amount of memory available in your system as well as what memory is currently being used by other applications
646
Mesh networks
Like ad-hoc networks, lots of devices communicate with each other device, forming a mesh if you were to draw lines for all the links between all the nodes
647
Metadata
Tells us everything we need to know about a file, including who created it, when it was last modified, who has access to it, and what type of file it is
648
Metered connection
An internet connection where all data transfer usage is tracked. Cell phone plans that have a limit on data usage per month or that charge based on usage are examples of metered connections
649
Micro display port
One of the standard power, data and display connector types used in mobile devices
650
Micro HDMI
One of the standard power, data and display connector types used in mobile devices
651
Microsoft Install Package(.msi) and MSI files
Microsoft Install Package is a file extension used to guide a program called Windows Installer in the installation, maintenance, and removal of programs of the windows operating systems. MSI files are a combination of of databases that contain installation instructions in different tables along with all the files
652
Microsoft Terminal Services Client
A client program used to create RDP connections to remote computers
653
Micro USB
One of the standard power, data and display connector types used in mobile devices
654
Mini HDMI
One of the standard power, data and display connector types used in mobile devices
655
Mini USB
One of the standard power, data and display connector types used in mobile devices
656
Mobile applications:
Software that is distributed on mobile OS devices
657
Mobile device management
A system used to apply and enforce rules about how the device has to be configured and used
658
Modify
An umbrella permission that includes read and execute and write
659
Motherboard
The body or circulatory system of the computer that connects all the pieces together
660
Mounting
Making a file or hard disk accessible to the computer
661
Multicast
A way of addressing groups of hosts all at once
662
Multilingual user interface
Interface that offers and support different languages
663
Multiplexing
It means that nodes on the network have the ability to direct traffic toward many different receiving services
664
MX record
It stands for mail exchange and this resource record is used in order to deliver email to the correct server
665
Name resolution
This process of using DNS to turn a domain name into an IP address
666
NAS device
A network attached storage device that has hard drives to automatically create backups and store data
667
Network
The interconnection of computers
668
Network Address Translation (NAT)
A mitigation tool that lets organizations use one public IP address and many private IP addresses within the network
669
Network file system
A protocol that enables files to be shared over a network
670
Networking
Managing, building and designing networks
671
Networking protocols
A set of rules for how we transfer data in a network
672
Network stack
A set of hardware or software that provides the infrastructure for a computer
673
Next header field
Defines what kind of header is immediately after this current one
674
Next hop
The IP address of the next router that should receive data intended for the destination networking question or this could just state the network is directly connected and that there aren't any additional hops needed. Defined as part of the routing table
675
Non-metered connection
A connection where your data usage is not tracked or limited, instead you are charged a flat fee for unlimited and unrestricted usage. A Wi-Fi connection is an example of a non-metered connection
676
Non-routable address space
They are ranges of IPs set aside for use by anyone that cannot be routed to
677
Northbridge
interconnects stuff like RAM and video cards
678
NS record
It indicates other name servers that may also be responsible for a particular zone
679
NTP
Network Time Protocol, keeping clocks synchronized on machines connected to a network
680
NTP servers
Used to keep all computers on a network synchronized in time
681
NVMe (NVM Express)
interface standard which allows greater throughput of data and increased efficiency
682
One-way cryptographic hash
The method used by AD to store passwords
683
OpenLDAP (lightweight directory access protocol)
An open source and free directory service
684
Open source
This means the developers will let other developers share, modify, and distribute their software for free
685
Open SSH
The most popular program to use SSH within Linux
686
Operating system
The whole package that manages our computers resources and lets us interact with it
687
Optical Network Terminator
Converts data from protocols the fiber network can understand to those that are more traditional twisted pair copper networks can understand
688
Options field
It is sometimes used for more complicated flow control protocols
689
OSI model
A model used to define how network devices communicate. This model has seven layers that stack on top of each other: Physical, Data Link, Network, Transport, Session, Presentation, and Application
690
OTA update
A type of update that is installed by the mobile device itself
691
Overclocking
it increases the rate of your CPU clock cycles in order to perform more tasks
692
Packaged archives
The core or source software files that are compressed into one file
693
Packaged managers
An application that makes package installation and removal easier
694
Padding field
A series of zeros used to ensure the header is the correct total size
695
Pairing
When a wireless peripheral connects to a mobile device, and the two devices exchange information, sometimes including a PIN or password, so that they can remember each other
696
Parameter
A value that is associated with a command
697
Parent directory & child directories
A parent directory is a directory that houses all subsequent child directories
698
Parent group
Groups that are principal groups and contain other groups
699
Partition
A logical division of a hard disk that is treated as a separate unit by operating systems and file systems
700
Partition table
How the disk is partitioned on an OS
701
Paths
A main directory that branches off and holds other directories and files
702
Payload length field
16-bit field that defines how long the data payload section of the datagram is
703
PC
Personal computer, which technically means a computer that one person uses
704
PCI Express
Peripheral Component Interconnect Express
705
PDA (Personal Digital Assistant)
Allows computing to go mobile
706
Peripherals
the external devices which we connect to our computer that add functionality, like: a mouse, a keyboard, and a monitor
707
Permission denied
An error message you might find when accessing a protected file
708
Personal package archives
A software repository for uploading source packages to be built and published
709
PHPLDAPadmin
A tool to manage OpenLDAP
710
Physical tokens
They take a few different forms, such as a USB device with a secret token on it, a standalone device which generates a token, or even a simple key used with a traditional lock
711
Pin Grid Array (PGA)
CPU socket where the pins are located on the processor itself
712
Platform as a service
A subset of cloud computing where a platform is provided for customers to run their services
713
Platform services
A platform for developers to completely build and deploy software applications, without having to deal with OS maintenance, server hardware, networking or other services that are needed to use the platform tools
714
Plink (PuTTY Link)
A tool built into the command line after PuTTY is installed that is used to make remote SSH connections
715
Pointer resource record
It resolves an IP to a name
716
Point-To-Point VPN
Establishes a VPN tunnel between two sites but VPN tunneling logic is handled by network devices at either side, so that users don't all have to establish their own connections
717
Policies
Settings that are reapplied every few minutes, and aren’t meant to be changed even by the local administrators
718
Port
It is a 16-bit number that's used to direct traffic to specific services running on a networked computer
719
Portable Executable (PE) format
Windows unique version of .exe
720
Port forwarding
A technique where specific destination ports can be configured to always be delivered to specific nodes
721
Port preservation
A technique where the source port chosen by a client, is the same port used by the router
722
Ports
Connection points that we can connect devices to that extend the functionality of our computer
723
POST (Power On Self Test):
It figures out what hardware is on the computer
724
Post-fail analysis
Investigating how a compromise happened after the breach is detected
725
Post mortem
A way for you to document any problems you discovered along the when recovering data, and the ways you fixed them so you can make sure they don't happen again
726
Powershell
A shell (program that interprets text commands) for Windows
727
Power supply
Converts electricity from our wall outlet onto a format that our computer can use
728
Power user
Above average computer users
729
Precedence
When computers are processing the Group Policy Objects that apply to them, all of these policies will be applied in a specific order based on a set of precedents rules
730
Presentation layer
It is responsible for making sure that the unencapsulated application layer data is actually able to be understood by the application in question
731
Preventative measures
Any procedures or systems in place that will proactively minimize the impact of a disaster
732
Primary account
The initial account you made during setup
733
Private cloud
When a company owns the services and the rest of the cloud infrastructure, whether on-site or in a remote data center
734
Processes
Help the computer run programs
735
Process Explorer
A utility Microsoft created to let IT support specialists and system administrators look at running processes
736
Process ID:
Unique identifier for processes on your computer
737
Process management
The capacity to manage the many programs in a system - when to run them, the order they run in, how many resources they take up, how long they run, et cetera
738
Process monitoring
A way of monitoring what processes are happening during installation
739
Process scheduler
The part of the kernel that makes multitasking possible
740
Procurement
Hardware is purchased or reused for an employee
741
Production
The parts of the infrastructure where certain services are executed and serve to its users production
742
Programming
Coding in a programming language
743
Programming language
Special languages that software developers use to write instructions for computers to execute
744
Programs
Basic instructions that tell the computer what to do
745
Prompt
A prompt shows you which directory you’re currently in
746
Protocol field
A protocol field is an 8-bit field that contains data about what transport layer protocol is being used
747
Proxy server
An intermediary between a company's network and the Internet, receiving network traffic and relaying that information to the company network
748
Proxy service
A server that acts on behalf of a client in order to access another service
749
PSH flag
One of the TCP control flags. PSH is short for push. This flag means that the transmitting device wants the receiving device to push currently- buffered data to the application on the receiving end as soon as possible
750
Public cloud
The cloud services provided by a third party
751
Public DNS servers
Name servers specifically set up so that anyone can use them for free
752
Punch cards
A sequence of cards with holes in them to automatically perform calculations instead of manually entering them by hand
753
Quad A (AAAA) record
It is very similar to an A record except that it returns in IPv6 address instead of an IPv4 address
754
Qwiklabs
An online platform which provides training in cloud services
755
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
755
Identification field
It is a 16-bit number that's used to group messages together
755
DACL
Directory Control Lists
755
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
756
RAID (redundant array of independent disks)
A method of taking multiple physical disks and combining them into one large virtual disk
757
Read and execute permission
Permissions that grant you access to read the file that exists and execute it if its runnable
758
Read permission
Permissions that grant you access to read the file that exists
759
Read-write replicas
Domain controllers in the Active Directory network that each have a complete copy of the AD database and are able to make changes to it
760
Receiving address
The MAC address of the access point that should receive the frame
761
Recursive name servers
Servers that perform full DNS resolution requests
762
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
762
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
762
Identification field
It is a 16-bit number that's used to group messages together
762
DACL
Directory Control Lists
762
Read and execute permission
Permissions that grant you access to read the file that exists and execute it if its runnable
762
RAM
Random Access Memory
763
Re-flash
A way to preserve end-user data on a device that you plan on resetting
764
Regions
A geographical location containing a number of data centers
765
Registers
An accessible location for storing the data that our CPU works with
766
Registrar
An organization responsible for assigning individual domain names to other organizations or individuals
767
Regular expression
A pattern matching language that describes words, phrases, or more complicated patterns; regular expressions are used to help you do advanced pattern based selection
768
Reimaging
The process of reimaging involves wiping and reinstalling an operating system using a disk image which is a copy of an operating system
769
Relative path
It is a path from your current directory
770
Remote wipe
A factory reset that you can trigger from your central MDM rather than having to do it in person on the device
771
Replication
the store directory data is copied and distributed across a number of physically distributed servers but still appears as one unified data store for querying and administering
772
Replication failure
A reason that a GPO might fail to apply as expected
773
Repository
A server that acts like a central storage location for packages
774
Reproduction case
Recreating an error to test a solution to make sure the problem is gone after a fix has been applied
775
Reset
When an SysAdmin restores or resets the password of a user
776
Resource monitoring
The most common way to quickly take a peek at how system resources are doing
777
Restart
A command that will let the machine reboot to complete a domain join
778
Restoration procedures
A recovery process and process needs to be tested regularly that is documented and accessible so that anyone with the right access can restore operation when needed
779
Resultant set of policy (RSOP)
The policy that forms when all of the group policies have been grouped together for a specific machine and apply precedence rules to them
780
Retirement
Hardware becomes unusable or no longer needed, and it needs to be properly removed from the fleet
781
Return merchandise authorization (RMA)
The process of receiving returned merchandise and authorizing a refund
782
Reverse lookup zone files
They let DNS resolvers ask for an IP, and get the FQDN associated with it returned
783
RGB model
RGB or red, green, and blue model is the basic model of representing colors
784
Risk assessment
Allows you to prioritize certain aspects of the organization that are more at risk if there’s an unforeseen event
785
Role-based access control (RBAC)
The process of changing a persons group that they are a part of when they have changed roles within a company to limit or change their access to resources
786
Rollback
Reverting to the previous state before you made changes
787
ROM chip (Read Only Memory)
A read-only memory chip where the BIOS is stored
788
Root cause
The main factor that's causing a range of issues
789
Root directory
A parent directory for all other directories in a file system
790
Root user
It is the first user that gets automatically created when we install a Linux OS and has all the privileges on the OS. Also called the super user. There's technically only one superuser or root account, but anyone that's granted access to use their powers can be called a superuser too
791
Round robin
It is a concept that involves iterating over a list of items one by one in an orderly fashion
792
Routing protocols
Special protocols the routers use to speak to each other in order to share what information they might have
793
RPM
Revolutions per minute
794
RSOP report
The process of troubleshooting group policy and comparing what you expect to be applied to a computer and the resultant set of policy report
795
RST flag
One of the TCP control flags. RST is short for reset. This flag means that one of the sides in a TCP connection hasn't been able to properly recover from a series of missing or malformed segments
796
SACL’s
System Access Control List
797
Safe operating temperature
The temperature range in which rechargeable batteries must be kept in order to avoid demanage
798
SATA
The most popular serial ATA drive, which uses one cable for data transfers
799
Scalability
The measure of a system’s ability to increase or decrease in performance and cost in response to varying loads in system processing demands
800
Script
It is run by an interpreter, which interprets the code into CPU instructions just in time to run them
801
Scripting
Coding in a scripting language
802
Scripts
Mainly used to perform a single or limited range task
803
SD devices
Mass storage devices like hard drives
804
SDRAM
It stands for Synchronous DRAM, this type of RAM is synchronized to our systems' clock speed allowing quicker processing of data
805
Secondary or stand-by machine
A machine that is the same as a production machine, but won't receive any traffic from actual users until enabled
806
Secure copy
A command you can use in Linux to copy files between computers on a network
807
Security account manager (SAM)
A database in windows that stores user names and password
808
Security filtering
A tool to make group policies apply more selectively
809
Security group
One of the two categories that groups in Active Directories can be part of, they can contain user accounts, computer accounts or other security groups
810
Security patch
A piece of software that is meant to fix up a security hole
811
Security principal
Any entity that can be authenticated by the system, such as a user account, a computer account, or a thread or process that runs in the security context of a user or computer account
812
Sequence control field
A field that is 16 bits long and mainly contains a sequence number used to keep track of ordering the frames
813
Sequence number
A 32-bit number that's used to keep track of where in a sequence of TCP segments this one is expected to be
814
Server logs
Text files that contains recorded information about activities performed on a specific web server in a defined period of time
815
Server operating systems
Regularly operating systems that are optimized for server functionality
816
Server or Service
A program running on a computer waiting to be asked for data
817
Servers
Devices that provide data to other devices that request that data, also known as a client
818
Service discovery
One of the services that the domain controller provides to the clients
819
Service type field
A eight bit field that can be used to specify details about quality of service or QoS technologies
820
Session layer
The network layer responsible for facilitating the communication between actual applications and the transport layer
821
Session manager subsystem
Process that is in charge of setting some stuff up to work for the OS
822
Shared folders
A way to share files between computers on the same network on Windows
823
Shell
A program that interprets text commands and sends them to the OS to execute
824
Shortcut
An entry in the MFT that has a reference to some destination, so that when you open it up, you get taken to that destination
825
Short-range wireless network
It is what mobile devices uses to connect to their peripherals
826
Side-by-side assemblies
A system that manages most shared libraries and resources on Windows and supports access to multiple versions of the same shared library automatically
827
Side-loading
A process of installing mobile apps directly without using an app store
828
Signal
A way to tell a process that something has just happened
829
Simple authentication and security layer (SASL)
The authentication method that can employ the help of security protocols like TLS, it requires the client and the directory server to authenticate using some method
830
Simple permissions
Special or specific permissions
831
Single point of failure
When one system in a redundant pair suffers a failure
832
SOC (System On a Chip)
Packs the CPU, Ram, and sometimes even the storage onto a single chip
833
Socket
The instantiation of an endpoint in a potential TCP connection
834
Softlinks
A shortcut in Linux, that allows us to link to another file using a file name
835
Software
The intangible instructions that tell the hardware what to do
836
Software as a Service (SaaS)
A way of licensing the use of software to others while keeping that software centrally hosted and managed
837
Software bug
An error in software that causes unexpected results
838
Software management:
A broad term used to refer to any and all kinds of software that are designed to manage or help manage some sort of project or task
839
Software services
The services that employees use that allow them to do their daily job functions, such as word processors, Internet browsers, email clients, chat clients, and more
840
Source port
A high numbered port chosen from a special section of ports known as ephemeral ports
841
Southbridge
It maintains our IO or input/output controllers, like hard drives and USB devices that input and output data
842
SRV record
A service record used to define the location of various specific services
843
SSD
Solid State Drive
844
SSH (Secure shell)
A protocol implemented by other programs to securely access one computer from another
845
SSH authentication key
A secure authentication method for accessing a computer from other device
846
SSH client
A program you must have installed on your device in order to establish an SSH connection with another device
847
SSH server
Software installed on a machine that allows for that device to accept an SSH connection
848
Standard error (stderr)
A data stream that redirects the output of error messages in a different output stream. It works both in Linux and Windows
849
Standard In (stdin)
A data stream in which the input that you provide through the keyboard goes to the standard in stream of the process that you're interacting with. It works both in Linux and Windows
850
Standardization
A systematic way of naming hosts
851
Standard out (stdout)
A data stream that, when a process creates output, it adds data to the standard out stream, which flows out of the process. It works both in Linux and Windows
852
Standard user
A user who is given access to the machine but has restricted access to do thing like install software or change certain setting
853
Standoffs
Used to raise and attach your motherboard to the case
854
Start of authority
A declaration of the zone and the name of the name server that is authoritative for it
855
Static IP address
An IP address that must be manually configured on a node
856
Subdirectories
A directory below or at a deeper level in the directory hierarchy
857
Subnet mask
32-bit numbers that are normally written as four octets of decimal numbers
858
Subnetting
The process of taking a large network and splitting it up into many individual smaller sub networks or subnets
859
Suspended apps
A command that will tell the OS to suspend background mobile apps
860
Swap space
The allocated space where the virtual memory is stored on the hard drive when the amount of physical memory space is used up or full
861
Switches
Devices that help our data travel
862
Symbolic links
Work similarly to shortcuts, but at the file system level. The key difference is that the operating system treats them like substitutes for the file they're linked to in almost every meaningful way
863
Symmetric Digital Subscriber Line (SDSL)
A device that establishes data connections across phone lines and has upload and download speeds that are the same
864
SYN_RECEIVED
A TCP socket state that means that a socket previously in a listener state, has received a synchronization request and sent a SYN_ACK back
865
SYN_SENT
A TCP socket state that means that a synchronization request has been sent, but the connection hasn't been established yet
866
SYN flag
One of the TCP flags. SYN stands for synchronize. This flag is used when first establishing a TCP connection and make sure the receiving end knows to examine the sequence number field
867
Sysinternals package
A set of tools released by Microsoft that can help you troubleshoot
868
System
A group of hardware components and software components that work together to fun the programs or processes in the computer
869
System Administration
The field in IT that is responsible for maintaining reliable computer systems, in a Multi-user environment
870
System properties
A control panel applet that allows you to edit the size and number and location of paging files
871
Systems administrator (sysadmin)
A person who works only in system administration, configuring servers, monitoring the network, provisioning, or setting up new users in computers and taking responsibility of systems
872
System settings
Settings like display resolution, user accounts, network, devices, etc
873
System software
Software used to keep our core system running, like operating system tools and utilities
874
Tab completion
A way to auto-complete a command or file names and directories
875
Task bar
It gives us quick options and shows us information like network connectivity, the date, system notifications, sound etc
876
Task Manager
A Windows utility that allows you to gain information about what tasks you have running in the background
877
T-Carrier technologies
Technologies Invented to transmit multiple phone calls over a single link. Eventually, they also became common transmission systems to transfer data much faster than any dial-up connection could handle
878
TCP checksum
A mechanism that makes sure that no data is lost or corrupted during a transfer
879
TCP segment
A payload section of an IP datagram made up of a TCP header and a data section
880
TCP window
The range of sequence numbers that might be sent before an acknowledgement is required
881
Terminal
A text based interface to the computer
882
Termination signal
A kill command that will stop whatever process you tell it to
883
Test environment
A virtual machine running the same configuration as a production environment, but isn't actually serving any users of the service
884
Thermal paste
A substance used to better connect our CPU and heat sink, so the heat transfers from to the other better
885
Time slice
A very short interval of time that gets allocated to a process for CPU execution
886
Time-To-Live field (TTL)
An 8-bit field that indicates how many router hops a datagram can traverse before it's thrown away
887
Top Level Domain (TLD)
The top level of the DNS or the last part of a domain name. For example, the “com” in www.weather.com
888
Total hops
The total number of devices data passes through to get from its source to its destination. Routers try to choose the shortest path, so fewest hops possible. The routing table is used to keep track of this
889
Total length field
A 16-bit field that indicates the total length of the IP datagram it's attached to
890
Traffic class field
An 8-bit field that defines the type of traffic contained within the IP datagram and allows for different classes of traffic to receive different priorities
891
Transmitter address
The MAC address of whatever has just transmitted the frame
892
Trim
A command to delete unused data blocks so the space can be used for the computer’s storage needs
893
Troubleshooting
The ability to diagnose and resolve a problem
894
TTL
The lifetime limit of data given in seconds. This number can be configured by the owner of a domain name for how long a name server is allowed to cache in entry before it should discard it and perform a full resolution again
895
Two-factor authentication
A technique where more than just a username and password are required to authenticate. Usually, a short-lived numerical token is generated by the user through a specialized piece of hardware or software
896
TXT record
It stands for text and was originally intended to be used only for associating some descriptive text with a domain name for human consumption
897
Type-C connector
A type of USB connector meant to replace many peripheral connections
898
Types of DNS servers
There are five primary types of DNS servers; caching name servers, recursive name servers, root name servers, TLD name servers, and authoritative name servers
899
Ubuntu
The most popular Linux consumer distribution
900
UEFI
United Extensible Firmware Interface, a new standard for BIOS
901
Uniform Resource Locator (URL)
A web address similar to a home address
902
Universal
The tool that is used to group global roles in a forest
903
Unix epoch
It is the number of seconds since midnight on January first, 1970. It's a 'Zero Hour' for Unix based computers to anchor their concept of time
904
Urgent pointer field
A field used in conjunction with one of the TCP control flags to point out particular segments that might be more important than others
905
URG flag
One of the TCP control flags. URG is short for urgent. A value of one here indicates that the segment is considered urgent and that the urgent pointer field has more data about this
906
USB (Universal Serial Bus)
A connection standard for connecting peripherals to devices such as computers
907
USB-C adapter
One of the standard power, data and display connector types used in mobile devices
908
User configuration
Contained within a Group Policy Object (GPO)
909
User Groups
The management of resources on a computer and on a network through organizing user accounts into various groups
910
User name
A unique identifier for a user account
911
User space
The aspect of an operating system that humans interact with directly like programs, such as text editors, music players, system settings, user interfaces, et cetera
912
UTF-8
The most prevalent encoding standard used today
913
UUID
Universally Unique ID
914
Variable
Files that constantly change
915
Version field
First field in an IP header that specifies the version of IP
916
Virtual Box
An application you can use to install Linux and have it completely isolated from your machine
917
Virtual instance
A single virtual machine
918
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
918
DACL
Directory Control Lists
918
Identification field
It is a 16-bit number that's used to group messages together
918
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
918
Read and execute permission
Permissions that grant you access to read the file that exists and execute it if its runnable
919
RAM
Random Access Memory
920
Virtualization
A single physical machine called a host runs many individual virtual instances called guests
921
Virtual machine (VM)
An application that uses physical resources like memory, CPU and storage, but they offer the added benefit of running multiple operating systems at once
922
Virtual memory
A combination of hard drive space and RAM that acts like memory which our processes can use
923
Volume
A format for a filesystem on a partition
924
WannaCry Attack
A cyber attack that started in Europe and infected hundreds of thousands of computers across the world
925
Web server
A web server stores and serves content to clients through the Internet.
926
Wide area network
Acts like a single network but spans across multiple physical locations. WAN technologies usually require that you contract a link across the Internet with your ISP
927
Wildcard
A character that is used to help select files based on a certain pattern
928
Windows domain
A network of computers and users that are added to a central database
929
Windows management instrumentation (WMI)
The container that is used to define powerful targeting rules for your GPO
930
Windows registry:
A hierarchical database of settings that Windows, and Windows applications, use for storing configuration data
931
Windows Search service
A service that indexes files on your computer by looking through them on a schedule
932
Windows store
A Windows store is an application repository or warehouse where you can download and instal universal Windows platform apps
933
Windows update client service
System that runs in the background on your computer to download and install updates and patches for your operating system
934
Wireless access point
A device that bridges the wireless and wired portions of a network
935
Wireless LANS (WLANS)
One or more access points act as a bridge between a wireless and a wired network
936
Wireless networking
Networks you connect to through radios and antennas
937
WMI filter:
A tool to make group policies apply more selectively on the configuration of the computer
938
Work group computer
A Windows computer that isn't joined to a domain
939
World Wide Web (WWW)
The information system that enables documents and other web resources to be accessed over the Internet
940
Write permission
A permission that allows you to make changes to a file
941
X.500 directory
The agreed upon directory standard that wa approved in 1988 that includes, DAP, DSP, DISP, DOP, DAP, and LDAP
942
Zone Files
Simple configuration files that declare all resource records for a particular zone
943
Read and execute permission
Permissions that grant you access to read the file that exists and execute it if its runnable
943
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
943
DACL
Directory Control Lists
943
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
943
RAM
Random Access Memory
943
Identification field
It is a 16-bit number that's used to group messages together
944
Read and execute permission
Permissions that grant you access to read the file that exists and execute it if its runnable
944
Backup and restore
A Microsoft offer and first party solution that has modes of operation, as a file based version where files are backed up to a zip archive
944
Identification field
It is a 16-bit number that's used to group messages together
944
Fragmentation
The process of taking a single IP datagram and splitting it up into several smaller datagrams
944
DACL
Directory Control Lists
944
RAM
Random Access Memory
