things to memorize Flashcards
(254 cards)
1
Q
What are the six steps of trouble shooting
A
▪ Identify the problem
▪ Establish a theory of probable cause
▪ Test the theory to determine the cause
● If the theory is not confirmed, re-establish a new theory
▪ Establish a plan of action to resolve the problem and implement the
solution
▪ Verify full system functionality
▪ Document the findings, actions, and outcomes
2
Q
“bit”
A
o A single “bit” can store one of two values: 1 or 0
3
Q
“Nibble”
A
is 4 bits
4
Q
1000 bits
A
▪ 1Kilobit (1Kb)
5
Q
how do we represent a “bit” and a “byte”
A
bit = b
byte = B
6
Q
DB 25 Connector
A
▪ A D-shaped sub miniature pin that goes into the back of a computer and
has two thumb screws on the side
7
Q
Serial Cable
A
▪ A cable that sends data in ones and zeros in a straight line, but it can only
send one bit at a time, which is measured at the speed of cables in bits
per second
8
Q
DB9 Connector
A
▪ A slow speed connection for much older mice keyboards and other
external modems
▪ A USB 1 and a USB 2 run at a much slower speed and should be split
across a hub
▪ A USB 1.0 has the slowest speed out of a USB with a maximum speed of
1.5 megabits per second
9
Q
USB 1.1
A
▪ Known as full speed and runs at 12 megabits per second
10
Q
USB 2.0
A
▪ Known as high speed and runs at 480 megabits per second
11
Q
USB 3.0
A
▪ Known as super speed and is at least 5 gigabits per second
12
Q
USB 3.1 Gen One
A
▪ Runs at 5 gigabits per second
13
Q
USB 3.1 Gen Two
A
▪ Runs at 10 gigabits per second
14
Q
USB 3.2 Gen 2x2
A
▪ Runs at 20 gigabits per second
15
Q
USB 4
A
▪ The most modern version of USB and can run at 40 gigabits per second
▪ A USB 4 and a USB 3.2 gen 2x2 must have a shorter cable because that is
going to give the best performance
▪ The longer a cable, the more likelihood that the cable would not work as
efficiently, or even at all
● Type A
● Type C
● Type B
● Type B Mini
● Type B Micro
16
Q
DVI
A
Used to support both analog and digital outputs
● DVI A - DVI A only supports analog signals,
● DVI D - DVI D only supports digital signals,
● DVI I - DVI I support both signals
17
Q
VGA
A
▪ The graphic standard that used a 15-pin standard analog video interface
port that would connect to the computer
18
Q
Thunderbolt
A
▪ Supports speeds of up to 40 gigabits per second for data transfer over
cables
19
Q
Lightning Cable
A
▪ A specific proprietary connector that was created by apple their mobile
devices
20
Q
SATA Cable
A
▪ The standard cables that are the main method of connecting a storage
device to a motherboard inside of a desktop computer
▪ The SATA cable has two cables, one is a seven-pin data cable, which does
not supply any power, and the other is a 15-pin SATA power connector to
provide the power to the device
▪ SATA version 1 can support speeds of up to 1.5 gigabits per second,
version 2 can support speeds of up 3 gigabits per second, and version 3
can support speeds of up to 6 gigabits per second
21
Q
External SATA or ESATA
A
▪ A SATA cable on the outside of the case
22
Q
PATA
A
▪ The old IDE connectors with the exact same cables and connectors and
standards but renamed for branding
▪ Parallel devices have each cable support up to two devices and they both
can communicate at the same time
23
Q
Molex Power Connector
A
▪ A 4-pin connector that would attach from the power supply directly to a
device
24
Q
SCIS
A
▪ A legacy parallel bus connector that allows multiple devices to be Daisy
chained together
▪ A narrow SCIS can support up to 7 devices, but a wide SCIS can support
up to 15 devices
25
Advanced Technology eXtended (ATX)
▪ Full-size motherboard and measures 12” x 9.6” in size (305mm x 244 mm)
26
Mini-ATX
▪ Smaller than ATX but contains the same features (11.2” x 8.2” / 284mm x
208 mm)
27
Micro-ATX (mATX)
▪ Measures 9.6 inches squared (244mm x 244mm)
▪ Micro-ATX is the same as ATX but only has 4 expansion card slots
28
Information Technology eXtended (ITX)
▪ Designed as a replacement for the ATX but never produced
29
Mini-ITX
▪ Measures 6.7” x 6.7” with only one expansion slot (170 x 170mm
squared)
● Mobile-ITX
30
CPU
▪ The brains of the computer that execute the different programing codes
in the software and firmware
▪ The CPU is performing the basic operations for every instruction in the
computer
▪ Once the processor has done the execution of the instruction, it will send
that information back to the memory so that it can be stored and used for
later use
31
X86
X86
▪ Can support a maximum of 4 gigabytes of Ram
32
X64
X64
▪ An extension of the X86 instruction set to be able to support 64-bit
operations
▪ 32 bit systems can only run 32 bit programs, but 64 bit processors can run
64 bit programs and 32 bit programs because they are fully backwards
compatible
33
Advanced RISC Machine (ARM)
▪ Used for low-power devices (tablets and cell phones)
● Extended battery life
● Produces less heat
▪ RISC systems use code to do tasks
34
CPU Sockets
ZIF
▪ The ability to insert the CPU without pressing down and applying
pressure to it
▪ If you bend, snap, or break a pin from a processor, the entire processor is
no longer functional
LGA Socket
▪ A form factor that positions all the pins to be able to connect the CPU
processor into the socket
PGA Form Factor
▪ The processor has the pins and the socket have holes which allows the
holes to align when installing the processor
Multi-Socket
▪ Multiple CPU's or processors installed on a motherboard
▪ You cannot upgrade or change out the processor on a mobile device
▪ The two main types of CPU sockets are LGA, which is made by Intel, and
we have PGA, which has made by AMD.
35
CPU Features
Simultaneous Multithreading (SMT) / Hyper-threading
▪ Single stream of instructions is being sent by a software application to a
processor
▪ Manufacturers developed a way to allow software to run multiple parallel
threads at the same time
36
Symmetric Multiprocessing (SMP)
▪ Traditional workstation and servers have multiple processors
37
Multi-core Processors
▪ Single CPU with multiple processors inside
▪ Multiple processors have multiple cores inside the CPU
38
Dual-core Processor
▪ Two CPUs inside a single chip
39
Quad-core Processor
▪ Four CPUs inside a single chip
40
Hexa-core Processor
▪ Six CPUs inside a single chip
41
Octa-core Processor
▪ Eight CPUs inside a single chip
● Hyper-threading / SMT
● Symmetric Multiprocessing
● Multi-core Processors
● Virtualization
42
VT and AMD-V
provide processor extensions to support virtualization
43
Virtualization
Virtualization allows running multiple systems on a single physical host
▪ Extended Page Table (EPT)
● Intel
▪ Rapid Virtualization Indexing (RVI)
● AMD
44
PCIe (PCI Express) replaces PCI, PCI-X, and AGP
▪ PCIe x1
▪ PCIe x4
▪ PCIe x8
▪ PCIe x16
● PCIe x1 is used for modems, network cards, wireless cards,
input/output devices, and audio cards
● PCIe x16 is used for graphics cards
45
Thermal Load
▪ Heat from different components inside the computer
46
Passive Cooling
▪ Type of cooling that doesn’t rely on moving parts or power
47
Heat Sink
▪ Finned metal device that radiates heat away from the processor
48
Thermal Paste
▪ Compound that ensures heat transfer by eliminating air gaps
● Passive cooling requires no power to operate and is silent when
operating
49
Active Cooling
▪ Uses a fan to cool down the heat from the device
50
Closed Loop System (liquid cooling)
▪ Cooling of a single component
51
Open Loop System (liquid cooling)
▪ Liquid cooling based system of different components
52
Power supply unit (PSU)
Converts AC power from the wall jack to DC power for computers components
53
120V AC (Low Line Power)
▪ US-based power supply
54
230V AC (High Line Power)
▪ Europe and Asia power supply
55
Random Access Memory (RAM)
▪ Used to load applications and files into a non-persistent and fast storage
area
56
Cache
▪ High-speed memory
57
Storage
▪ Mass storage device that holds more data but is slower than a cache
58
Mass Storage Devices
▪ Permanent storage area
59
Random Access Memory (RAM) / System Memory
▪ Temporary storage area/non-persistent storage
60
Disk Cache
▪ Pulls the files from the disc into memory and replaces the old file
61
Dynamic RAM (DRAM)
▪ Oldest type of memory that requires frequent refreshing
● DRAM storage cell is dynamic
62
Synchronous DRAM (SDRAM)
▪ First memory module that operates at the same speed as the
motherboard bus (168-pin connector)
● PC66 (66 MHz bus)
● PC133 (133 MHz bus)
● PC266 (266 MHz bus)
63
Double Data Rate Synchronous Dynamic Random-Access Memory (DDR
SDRAM)
▪ Doubles the transfer speed of an SRAM module (184-pin connector)
64
Double Data Rate 2 Synchronous Dynamic Random-Access Memory (DDR2
SDRAM)
▪ Higher latency and has faster access to the external bus (240-pin
connector)
● PC2-4200
65
Double Data Rate 3 Synchronous Dynamic Random-Access Memory (DDR3
SDRAM)
▪ Runs at a lower voltage and at a higher speed than DDR2 (240 keyed pin
connector)
● PC3-10600
▪ DDR3 throughput is 6.4 to 17 GB/s with a maximum module size of 8GB
per memory module
66
Small Outline Dual In-line Memory Module (SODIMM)
▪ Classified as DDR3, DDR4, or DDR5
67
Multi-Channel Memory
▪ Uses two different memory modules to increase the performance and
throughput
68
Single-Channel
● Uses one memory module on one bus (64-bit data bus)
69
Dual-Channel
● Requires two memory modules and two memory slots on the
motherboard (128-bit data bus)
70
Triple-Channel
● Uses three memory modules and three memory slots (192-bit
data bus)
71
Quad-Channel
● Uses four memory modules and four memory slots (256-bit data
bus)
72
Multiple modules
● Give faster speeds and add memory for storage
73
Non-Parity Memory
▪ Standard memory that does not check for errors and allows data to be
put in or taken out
74
Parity Memory
▪ Performs basic error checking and ensures the memory contents are
reliable
● A parity check does basic calculation
o Every bit has an associated parity bit
▪ Bits can only be a zero or one
75
Error Correcting Code (ECC)
▪ Detects and corrects an error
76
Virtual Memory/Page File
▪ Space on a hard drive that is allocated by the OS and pretends to be
memory
77
DDR5
▪ Has an internal error checking for its modules
● DDR5 modules can still be sold as ECC or non-ECC modules
78
DDR4 and DDR5 have how many pins?
288
79
BIOS and UEFI
Basic Input/Output System (BIOS)
▪ Program that a CPU uses to start the computer system
▪ BIOS serves as a method of configuring the motherboard using a
text-based interface
80
Firmware
▪ Software on a chip and contains BIOS program code in the flash memory
of a motherboard
81
Unified Extensible Firmware Interface (UEFI)
▪ Supports 64 bit processors and provides a GUI
82
Read-Only Memory (ROM)
▪ Type of chip embedded in the motherboard and can be upgraded through
flashing
83
Power-On Self-Test (POST)
▪ Diagnostic testing sequence to check the computer’s basic input/output
system
84
BIOS/UEFI Security
- BIOS and UEFI are used during loading and booting up the OS
- Computers that rely on BIOS use MBR to hold the boot information
- Computers that rely on UEFI use GPT to hold the boot information
85
Trusted Platform Module (TPM)
▪ Specification for hardware-based storage of digital certificates, keys,
hashed passwords, and other user and platform identification
information
● TPM is a hardware RoT
● Secured boot-up
● Provides encryption
▪ A TPM can be managed in Windows via tpm.msc console
or through group policy
86
Hardware Root of Trust (RoT)
▪ Cryptographic module embedded in a computer system that endorses
trusted execution and attests to boot settings and metrics
87
Hardware Security Module (HSM)
▪ Appliance for generating and storing cryptographic keys that
is less susceptible to tampering and insider threats
88
Hard Disk Drive (HDD)
▪ Form of mass storage device
89
Mass Storage Device
▪ Non-volatile storage device that holds the data when the system
is powered down (GB or TB)
90
Redundant Array of Independent Disks (RAID)
▪ Combination of multiple physical hard disks that is recognized by the
operating system
91
RAID 0
RAID 0 is great for speed but provides no data redundancy
RAID 0 has no loss of space on the disks
92
RAID 1
RAID 1 provides full redundancy
93
Failure Resistant
▪ Protection against the loss of erased data (RAID 1/RAID 5)
94
Fault Tolerant
▪ Raid can function even when a hard drive fails (RAID 1/RAID 5/RAID 6)
95
Disaster Tolerant
▪ RAID with two independent zones with full data access (RAID 10)
▪ RAIDs provide redundancy and high-availability
96
Virtualization
▪ Host computer installed with a hypervisor that can be used to install and
manage multiple guest operating systems or virtual machines (VMs)
97
Type I Hypervisor (Bare Metal)
runs directly on the host hardware and functions as the
operating system
98
Type II Hypervisor
Runs within the normal operating system
99
VM Escape
▪ Threat attempts to get out of an isolated VM and send commands to the
underlying hypervisor
▪ VM escape is easier to perform on a Type II hypervisor than a Type I
hypervisor
100
VM Hopping
▪ Threat attempts to move from one VM to another on the same host
101
Sandbox Escape
▪ Occurs when an attacker circumvents sandbox protections to gain access
to the protected OS or other privileged processes
102
Live Migration
▪ Migrates the virtual machine from one host to another while it is running
▪ Ensure that live migration only occurs on a trusted network or utilizes
encryption
103
Data Remnants
▪ Leftover pieces of data that may exist in the hard drive which are no
longer needed
● Encrypt virtual machine storage location
● Destroy encryption key
104
VM Sprawl
105
Cloud Computing
▪ The practice of using a network of remote servers hosted on the Internet
106
Rapid Elasticity (cloud computing)
The ability to quickly scale up or down
● Elasticity is the system’s ability to handle changes to demand in
real time
107
Metered Utilization (cloud computing)
▪ Being charged for a service on a pay per use basis
▪ The benefit of using the cloud is that most things are done on a metered
basis
108
Measured Services (cloud computing)
▪ Charging is based upon the actual usage of the service being consumed
▪ Measured services are charged based on the actual usage of the service
being consumed
108
Public Cloud
▪ Systems and users interact with devices on public networks, such as the
Internet and other clouds
109
Shared Resources (cloud computing)
▪ The ability to minimize the costs by putting VMs on other servers
▪ Shared resources is pooling together all the hardware to make a cloud
provider
110
File Synchronization (cloud computing)
▪ The ability to store data that can spread to other places depending on the
configuration
111
Private Cloud
▪ Systems and users that only have access with other devices inside the
same private cloud or system
112
Hybrid Cloud
▪ Combination of private and public clouds
113
Community Cloud
▪ Collaborative effort where infrastructure is shared between several
organizations from a specific community with common concerns
114
Multitenancy
▪ The ability for customers to share computing resources in a public or
private cloud
115
Single-Tenancy
▪ Assigns a particular resource to a single organization
116
On-Premise Solution
▪ The need to to procure hardware, software, and personnel necessary to
run the organization’s cloud
▪ On-premise solution allows the ability to control all the physical and
logical access to servers
117
Hosted Solution
▪ Third-party service provider that provides all the hardware and facilities
needed to maintain a cloud solution
117
Hosted Model/ Desktop as a Service (DAAS)
▪ Maintained by a service provider and provided to the end user as a
service
118
Virtual Desktop Infrastructure (VDI)
▪ Hosts desktop OSs within a virtualized environment hosted by a
centralized server or server farm
119
Remote Virtual Desktop Model
▪ Copies the desktop image to a local machine prior to being used by the
end user
120
Personal Area Network (PAN)
▪ Smallest type of wired or wireless network and covers
the least amount of area
121
Local Area Network (LAN)
▪ Connects components within a limited distance
● Up to a few hundred feet
122
Campus Area Network (CAN)
▪ Connects LANs that are building-centric across a university, industrial
park, or business park
● Up to a few miles
123
Metropolitan Area Network (MAN)
▪ Connects scattered locations across a city or metro area
● Up to about 25 miles
124
Wide Area Network (WAN)
▪ Connects geographically disparate internal networks and consists of
leased lines or VPNs
● Worldwide coverage
125
Wireless Local Area Network (WLAN)
▪ A wireless distribution method for two or more devices that creates a
local area network using wireless frequencies
126
Storage Area Network (SAN)
▪ Provisions access to configurable pools of storage devices that can be
used by application server
127
Channel
▪ A virtual medium through which wireless networks can send and receive
data
● For the 2.4 GHz spectrum, there can be 11 or 14 channels
● Channels 1, 6, and 11 avoid overlapping frequencies in the 2.4
GHz band
● We can use 5.725-5.875 GHz to run our wireless networks in the 5
GHz band
● There are 24 non-overlapping channels in the 5 GHz band
128
What 802.11 standards use 5ghz
802.11a
-5GHz, 54Mbps
802.11n
-2.4 and 5GHz, 150Mbps/600Mbps (MIMO) WiFi-4
802.11ac
-5GHz, 6.9Gbps (MU-MIMO) WiFi-5
802.11X
-2.4, 5, 6GHz 9.6Gbps (MU-MIMO) WIFI-6
129
What 802.11 Standards are only 2.4Ghz
802.11b
-2.4Ghz 11Mbps
802.11g
-2.4Ghz 54Mbps
130
Multiple-Input and Multiple-Output (MIMO)
▪ Uses multiple antennas to send and receive data than it could with a
single antenna
131
Multiple User Multiple Input Multiple Output (MU-MIMO)
▪ Allows multiple users to access the wireless network and access point at
the same time
132
Radio Frequency Interference (RFI)
▪ Occurs when there are similar frequencies to wireless networks in the
area
133
Wired Equivalent Privacy (WEP)
▪ Original 802.11 wireless security standard which is an insecure security
protocol
▪ WEP uses 24-bit Initialization Vector (IV) sent in clear text
134
Wi-Fi Protected Access (WPA)
▪ Replaced WEP and follows the Temporal Key Integrity Protocol (TKIP)
▪ WPA uses 48-bit Initialization Vector (IV) instead of 24-bit
● Rivest Cipher 4 (RC4)
- For encryption
● Message Integrity Check (MIC)
- To confirm data was not modified in transit
135
Wi-Fi Protected Access 2 (WPA2)
▪ Created as part of IEEE 802.11i standard and requires stronger encryption
and integrity checking through CCMP
▪ Advanced Encryption Standard (AES)
- provides additional security by using a 128-bit key or
higher
136
MAC Address Filtering
▪ Configures an access point with a listing of permitted MAC addresses (like
an ACL)
137
Disabling SSID Broadcast
▪ Configures an access point not to broadcast the name of the wireless LAN
138
Cellular (wireless networks)
▪ Uses a larger antenna and a larger hotspot powered by a power outlet
within an office or home
139
Microwave
▪ Creates point to point connection between two or more buildings that
have longer distances
▪ A traditional microwave link can cover about 40 miles of distance
140
Satellite
▪ A long range and fixed wireless solution that can go for miles
● Low Earth Orbit
- Requires more satellites to cover the entire planet but
gives lower latency speeds
● Geosynchronous Orbit
- One satellite can cover a large portion of the Earth
- Geosynchronous orbit gives higher latency and lower
quality
141
Near Field Communication (NFC)
▪ Uses radio frequency to send electromagnetic charge containing the
transaction data over a short distance
142
Radio Frequency dentification (RFID)
▪ A form of radio frequency transmission modified for use in authentication
systems
143
Infrared Data (IrDA)
▪ Allows two devices to communicate using line of sight communication
in the infrared spectrum
144
Bluetooth
▪ Creates a personal area network over 2.4 GHz to allow for wireless
connectivity
145
Bluejacking
Sending unsolicited messages to a Bluetooth device
146
Bluesnarfing
Making unauthorized access to a device via Bluetooth
connection
147
BlueBorne
Allows the attacker to gain complete control over a device
without even being connected to the target device
148
Tethering
▪ Sharing cellular data Internet connection from a smartphone
to multiple other devices
▪ Only connect to trusted wireless networks
149
Fiber To The Curb (FTTC)
▪ Runs a fiber optic cable from an internet provider access point to a curb
150
Fiber To The Premises (FTTP)
▪ Fiber optic that connects directly to a building and connects to an optical
network terminal (ONT)
151
Optical Network Terminal (ONT)
▪ Physical devices that convert optical signals to electrical signals
152
Link/Network Interface Layer
▪ Responsible for putting frames in the physical network’s transmission media
▪ In the link/network interface layer, the data can only travel through the local area network
153
Internet Layer
▪ Used to address packets and route them across the network
154
Transport Layer
▪ Shows how to send the packets
● (TCP) Transmission Control Protocol
● (UDP) User Datagram Protocol
155
Application Layer
▪ Contains all the protocols that perform higher-level functions
156
● IPv4 Class A
1st octet starts 1-127
157
● IPv4 Class B
1st octet starts 128-191
158
● IPv4 Class C
1st octet starts 192-223
159
● IPv4 Class D
1st octet starts 224-239
160
● IPv4 Class E
1st octet starts 240-255
161
Public (Routable) IP Address
▪ Can be accessed over the Internet and is assigned to the network by an Internet service provider
162
Private (Non-Routable) IP Address
▪ Can be used by anyone any time, but only within their own local area network
▪ Private IP ranges include those that start with either 10, 172, or 192
163
Loopback Address (127.0.0.1)
▪ Creates a loopback to the host and is often used in troubleshooting and testing network protocols on a system
164
Automatic Private IP Addresses (APIPA)
▪ Used when a device does not have a static IP address or cannot reach a DHCP server
● 169.254.0.0 to 169.254.255.255
D iscover
O ffer
R equest
A cknowledge
165
Static Assignment
▪ Manually type the IP address for the host, its subnet mask, default gateway, and DNS server
▪ Static assignment of IP addresses is impractical on large enterprise networks
166
Dynamic Assignment
▪ Dynamic allocation of IP addresses (DHCP SERVER)
167
Domain Name System (DNS)
▪ Converts the domain names used by a website to the IP address of its server
▪ DNS is the internet version of a phone book
168
Windows Internet Name Service (WINS)
▪ Identifies NetBIOS systems on a TCP/IP network and converts those NetBIOS names to IP addresses
169
Bootstrap Protocol (BOOTP)
▪ Dynamically assigns IP addresses and allows a workstation to load a copy of boot image to the network
170
Dynamic Host Control Protocol (DHCP)
▪ Assigns an IP based on an assignable scope or addresses and provides the ability to configure other options
▪ 192.168.1.100 through 192.168.1.200
● Each IP is leased for a period of time and returns to the pool when the lease expires
171
Automatic Private IP Addressing (APIPA)
▪ Used when a device does not have a static IP address or cannot reach a DHCP server
▪ Allows for the quick configuration of a LAN without the need for a DHCP server
▪ APIPA-assigned devices cannot communicate outside the LAN or with non-APIPA devices
172
Zero Configuration (ZeroConf)
▪ New technology that provides the same features as APIPA
▪ Assign an IPv4 link-local address to a client
▪ Resolve computer names to IP addresses without the need for DNS by using mDNS (multicast domain name service)
▪ Perform service discovery on a network
● Windows
- Link-Local Multicast Name Resolution (LLMNR)
● Linux
-SystemD
173
Domain Name System (DNS)
▪ Helps network clients find a website using human-readable hostnames instead of numeric IP addresses
174
Fully Qualified Domain Name (FQDN)
▪ Domain name under a top-level provider Ex. is .UK .US .COM .NET
175
DNS Records
A - Links host name to an IPv4 address
AAAA - links a host name to an IPv6 address
CNAME - points a domain to another domain or sub domain - (CNAME records can only be used to point to another domain or subdomain, not to an IP address)
MX - directs e-mails to an email server
TXT - adds texts into a DNS
NAMESERVER - indicates which DNS name server has authority
176
DomainKeys Identified Mail (DKIM)
▪ provides the cryptographic authentication mechanism for mail using a public key published as a DNS record
177
Domain-based Message Authentication, Reporting & Conformance (DMARC)
▪ Framework that is used for proper application of SPF and DKIM, utilizing a policy that’s published as a DNS record
178
Nameserver
▪ Type of DNS server that stores all the DNS records for a given domain
179
Internal DNS
▪ Allows cloud instances on the same network access each other using internal DNS names
180
External DNS
▪ Records created around the domain names from a central authority and used on the public Internet
181
Time to Live (TTL)
▪ Tells the DNS resolver how long to cache a query before requesting a new one
182
DNS Resolver/DNS Cache
▪ Makes a local copy of every DNS entry it resolves as connected to websites
183
Recursive Lookup
▪ DNA server communicates with several other DNS servers to hunt down
the IP address and return to the client
184
Iterative Lookup
▪ Each DNS server responds directly to the client with an address for another DNS server that may have the correct IP address
185
Virtual Local Area Network (VLAN)
▪ Allows different logical networks to share the same physical hardware and provides added security and efficiency
186
Virtual Private Network (VPN)
▪ Extends a private network across a public network and enables sending and receiving data across shared or public networks
187
Full Tunnel VPN
▪ Routes and encrypts all network requests through the VPN connection back to the headquarters
188
Split Tunnel VPN
▪ Routes and encrypts only the traffic bound for the headquarters over the VPN, and sends the rest of the traffic to the regular Internet
189
Clientless VPN
▪ Creates a secure remote-access VPN tunnel using a web browser without requiring a software or hardware client
190
Secure Socket Layer (SSL)
▪ Provides cryptography and reliability using the upper layers of the OSI model (Layers 5, 6, and 7)
191
Transport Layer Security (TLS)
▪ Provides secure web browsing over HTTPS
192
Dual Stack
▪ Simultaneously runs both the IPv4 and IPv6 protocols on the same network devices
193
Tunneling
▪ Allows an existing IPv4 router to carry IPv6 traffic
194
● Simple Mail Transfer Protocol (SMTP)
o Port 25
o Provides the ability to send emails over the network
195
● Dynamic Host Control Protocol (DHCP)
o Ports 67, 68
o Automatically provides network parameters such as
assigned IP address, subnet mask, default gateway, and the
DNS server
196
● Domain Name Service (DNS)
o Port 53
o Converts domain names to IP addresses, and IP address
to domain names
197
● Hypertext Transfer Protocol (HTTP)
o Port 80
o Used for insecure web browsing
198
● Post Office Protocol Version Three (POP3)
o Port 110
o Used for receiving incoming emails
199
● Network Basic Input/Output System (NetBIOS)7
o Ports 137, 139
o Used for file or printer sharing in a Windows network
200
● Internet Mail Application Protocol (IMAP)
o Port 143
o A newer method of retrieving incoming emails which
improves upon the older POP3
201
● Simple Network Management Protocol (SNMP)
o Ports 161, 162
o Used to collect data about network devices and monitor
their status
202
● Lightweight Directory Access Protocol (LDAP)
o Port 389
o Used to provide directory services to your network
203
● Hypertext Transfer Protocol – Secure (HTTPS)
o Port 443
o Used as a secure and encrypted version of web browsing
▪ SSL (Secure Socket Layer)
▪ TLS (Transport Layer Security)
204
● Server Message Block (SMB)
o Port 445
o Used for Windows file and printer sharing services
205
● Remote Desktop Protocol (RDP)
o Port 3389
o Provides graphical remote control of another client or
server
o RDP provides a full graphical user interface
206
● TCP (Connection-Oriented)
o SSH, HTTP or HTTPS
207
● UDP (Connectionless)
o Audio, video streaming, DHCP, and TFTP
208
▪ Dynamic Host Control Protocol (DHCP)
● Ports 67, 68
● Automatically provides network parameters
such as assigned IP address, subnet mask,
default gateway, and the DNS server
209
▪ Trivial File Transfer Protocol (TFTP)
● Ports 69
● a connectionless protocol that uses UDP as
its transport
210
Server
▪ Can be configured to allow the clients on the network to access the network and be able to read and write to its disk (file share)
211
Print Server
▪ Another server that could be a physical workstation or network infrastructure that provides printing functionality
212
Windows-based file and print server
- Relies on the NetBIOS protocol or SMB
● Network Basic Input/Output System (NetBIOS)
- Ports 137, 139
- Used for file or printer sharing in a Windows network
● Server Message Block (SMB)
- Port 445
- Used for Windows file and printer sharing services
213
Samba
▪ Provides the ability for a Linux or Unix server to be able to host files or printers that can then be used by Windows clients running the SMB protocol
214
Web Servers
▪ Any server that provides access to a website
● HTTP
- Port 80
● HTTPS
- Port 443
215
Internet Information Services (IIS)
▪ Extensible web server software, created by Microsoft (HTTP, HTTP/2, and HTTPS)
216
Apache
▪ Most popular way to run a web server these days
217
NGINX
▪ Reverse proxy, load balancer, mail proxy, and HTTP cache
218
Uniform Resource Locator (URL)
▪ Combines the fully qualified domain name with a protocol at the beginning
219
● Simple Mail Transfer Protocol (SMTP)
- Specifies how emails should be delivered from one mail
domain to another
- Send mail transfer protocol
- SMTP operates over port 25
220
● Post Office Protocol 3 (POP3)
- Older email protocol which operates over port 110
221
● Internet Message Access Protocol (IMAP)
- Mail retrieval protocol
- IMAP operates over port 143 and can connect to a server
and receive and read messages
222
● Microsoft Exchange
- Mailbox server environment designed for Windows-based
domain environments
223
802.1x
▪ Standardized framework used for port-based authentication on wired and
wireless networks
224
Authentication
▪ Occurs when a person’s identity is established with proof and is confirmed by the system
● Something you know
● Something you are
● Something you have
● Something you do
● Somewhere you are
225
Lightweight Directory Access Protocol (LDAP)
▪ A database used to centralize information about clients and objects on the network
226
o Active Directory (AD)A
▪ Used to organize and manage the network, including clients, servers, devices, users, and groups
227
Remote Authentication Dial-In User Service (RADIUS)
▪ Provides centralized administration of dial-up, VPN, and wireless
authentication services for 802.1x and the EAP
● RADIUS operates at the application layer
● RADIUS utilizes UDP for making connections
228
Terminal Access Controller Access-Control System Plus (TACACS+)
▪ Proprietary version of RADIUS that can perform the role of an authenticator in 802.1x networks
229
Authorization
▪ Occurs when a user is given access to a certain piece of data or certain areas of a building
230
Kerberos
▪ Authentication protocol used by Windows to provide for two-way (mutual) authentication using a system of tickets
▪ A domain controller can be a single point of failure for Kerberos
231
Telnet Port 23
▪ Sends text-based commands to remote devices and is a very old networking protocol
▪ Telnet should never be used to connect to secure devices
232
Secure Shell (SSH) Port 22
▪ Encrypts everything that is being sent and received between the client and the server
233
Remote Desktop Protocol (RDP) Port 3389
▪ Provides graphical interface to connect to another computer over a network connection
▪ Remote desktop gateway (RDG) creates a secure connection to tunnel into the RDP
234
Virtual Network Computing (VNC) Port 5900
▪ Designed for thin client architectures
235
Terminal Emulator (TTY)
▪ Any kind of software that replicates the TTY I/O functionality to remotely connect to a device
▪ TTY is the terminal or end point of the communication between the computer and the end-user
236
Syslog
▪ Enables different appliances and software applications to transmit logs to
a centralized server
▪ Syslog is the de facto standard for logging events
● PRI code (Priority code)
● Header
● Message
237
Proxy Server
▪ Devices that create a network connection between an end user’s client machine and a remote resource (web server)
● Increased network speed and efficiency
● Increased security
● Additional auditing capabilities
238
Load Balancer/ Content Switch
▪ Distributes incoming requests across a number of servers inside a server farm or a cloud infrastructure
▪ A load balancer is one of the key things to help defend against a DoS attack or a DDoS attack
239
Access Control List (ACL)
▪ Rule sets placed on the firewalls, routers, and other network devices that permit or allow traffic through a particular interface
▪ The actions are performed top-down inside of an ACL
● Top
- Specific rules
● Bottom
- Generic rules
240
Firewall
▪ Inspects and controls the traffic that is trying to enter or leave a network’s boundary
● Packet-filtering
● Stateful
● Proxy
● Dynamic packet-filtering
● Kernel proxy
241
Unified Threat Management (UTM)
▪ Provides the ability to conduct security functions within a single device or network appliance
242
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245
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247
248
249
250
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