Terms and Such 1101 A+ Flashcards
1
Q
802.11
A
– Local area network (LAN)
– High speed, Internet access
2
Q
Near-field communication (NFC)
A
- Short-distance networking
– 4 centimeters or less
– Data transfers or authentication - Common on mobile phones and smart watches
– Payment method on your wrist - Use it for authentication without typing a password
– Hospital workstations, warehouses, manufacturing
3
Q
Fluorescent vs. LED backlighting
A
- LED-backlit LCD display
– Backlight is LEDs instead of florescent
– LEDs around the edge of the screen
– An array of LEDs behind the screen
– The latest laptops are LED-backlit - CCFL - Cold Cathode
– Fluorescent Lamp
– Higher voltage and power needed
– Added thickness to the display
– No longer a common backlight
– Older laptops will use these
4
Q
Backlight and inverter
A
- LCD displays need a backlight
– Florescent lamp/LED to LCD display to your eyes - Some laptops have inverters - Turn DC into AC
- Verify backlight
– Look closely and use a flashlight - May need to replace the LCD inverter or display
– Choose carefully
5
Q
Digitizer
A
- Use a pen-like device as input
– Stylus input - Useful for graphical input
-– Digitizer responds to touch - No keyboard required - Used commonly on laptop / tablets
– Or hybrid devices
6
Q
Microsoft 365
A
- Outlook, Exchange
– Microsoft’s email service
– Usually the same for Hotmail and Outlook.com - Select the items to synchronize
– Changes in Outlook will appear on the mobile device - Data types
– Mail
– Pictures, music, video
– Calendar
– Contacts
7
Q
TCP – Transmission Control Protocol
A
- Connection-oriented
– A formal connection setup and close - “Reliable” delivery
– Recovery from errors
– Can manage out-of-order messages or retransmissions - Flow control
– The receiver can manage how much data is sent
8
Q
UDP – User Datagram Protocol
A
- Connectionless - No formal open/close to the connection
- “Unreliable” delivery
– No error recovery
– No reordering of data or retransmissions - No flow control
– Sender determines the amount of data transmitted
9
Q
FTP - File Transfer Protocol
A
- tcp/20 (active mode data), tcp/21 (control)
– Transfers files between systems - Authenticates with a username and password
– Some systems use a generic/anonymous login - Full-featured functionality - List, add, delete, etc
10
Q
SSH - Secure Shell
A
- Encrypted communication link - tcp/22
- Looks and acts the same as Telnet
11
Q
Telnet
A
- Telnet – Telecommunication Network - tcp/23
- Login to devices remotely
– Console access - In-the-clear communication
– Not the best choice for production systems
12
Q
SMTP - Simple Mail Transfer Protocol
A
- SMTP - Simple Mail Transfer Protocol
– Server to server email transfer - tcp/25 - Also used to send mail from a device to a mail server
– Commonly configured on mobile devices and email clients - Other protocols are used for clients to receive email
– IMAP, POP3
13
Q
DNS - Domain Name System
A
- Converts names to IP addresses - udp/53
– www.professormesser.com = 162.159.246.164 - These are very critical resources
– Usually multiple DNS servers are in production
14
Q
DHCP - Dynamic Host Configuration Protocol
A
- Automated configuration of IP address, subnet mask and
other options - udp/67, udp/68
– Requires a DHCP server
– Server, appliance, integrated into a SOHO router, etc. - Dynamic / pooled
– IP addresses are assigned in real-time from a pool
– Each system is given a lease and must renew at set intervals - DHCP reservation
– Addresses are assigned by MAC address in the DHCP server
– Manage addresses from one location
15
Q
POP3 / IMAP
A
- Receive emails from an email server
– Authenticate and transfer - POP3 - Post office Protocol version 3
– tcp/110
– Basic mail transfer functionality - IMAP4 - Internet Message Access Protocol v4
– tcp/143
– Includes email inbox management from multiple clients
16
Q
SMB - Server Message Block
A
- Protocol used by Microsoft Windows
– File sharing, printer sharing
– Also called CIFS (Common Internet File System) - Using NetBIOS over TCP/IP
(Network Basic Input/Output System)
– udp/137 - NetBIOS name services (nbname)
– tcp/139 - NetBIOS session service (nbsession) - Direct over tcp/445 (NetBIOS-less)
– Direct SMB communication over TCP without the NetBIOS transport
17
Q
SNMP - Simple Network Management Protocol
A
- Gather statistics from network devices
– Queries: udp/161
– Traps: udp/162
18
Q
LDAP (Lightweight Directory Access Protocol
A
- LDAP (Lightweight Directory Access Protocol) - tcp/389
- Store and retrieve information in a network directory
– Commonly used in Microsoft Active Directory
19
Q
RDP - Remote Desktop Protocol
A
- Share a desktop from a remote location over tcp/3389
- Remote Desktop Services on many Windows versions
- Can connect to an entire desktop or just an application
- Clients for Windows, macOS, Linux, Unix, iPhone, Android, and others
20
Q
Switches
A
- Bridging done in hardware
– Application-specific integrated circuit (ASIC)
– Forwards traffic based on data link address - Many ports and features
– The core of an enterprise network
– May provide Power over Ethernet (PoE) - Multilayer switch
– Includes routing functionality
21
Q
Patch Panels
A
- Combination of punch-down blocks and RJ-45 connectors
- Runs from desks are made once
– Permanently punched down to patch panel - Patch panel to switch can be easily changed
– No special tools
– Use existing cables
22
Q
Firewalls
A
- Filters traffic by port number
– OSI layer 4 (TCP/UDP)
– Some firewalls can filter based on the application - Can encrypt traffic into/out of the network
– Protect your traffic between sites - Can proxy traffic
– A common security technique - Most firewalls can be layer 3 devices (routers)
– Usually sits on the ingress/egress of the network
23
Q
Hub
A
- “Multi-port repeater”
– Traffic going in one port is repeated to every other port - Everything is half-duplex
- Becomes less efficient as network traffic increases
- 10 megabit / 100 megabit
24
Q
Cable modem
A
- Broadband
– Transmission across multiple frequencies
– Different traffic types - Data on the “cable” network
– DOCSIS (Data Over Cable Service Interface Specification) - High-speed networking
– Speeds up to 1 Gigabit/s are available - Multiple services
– Data, voice, video
25
Q
DSL modem
A
- ADSL (Asymmetric Digital Subscriber Line)
– Uses telephone lines - Download speed is faster than the upload
speed (asymmetric)
– ~10,000 foot limitation from the central office (CO)
– 52 Mbit/s downstream / 16 Mbit/s upstream are
common
– Faster speeds may be possible if closer to the CO
26
Q
ONT
A
- Optical network terminal
– Fiber to the premises - Connect the ISP fiber network to the copper network
– Demarcation point (demarc) in the data center
– Terminal box on the side of the building - Line of responsibility
– One side of the box is the ISP
– Other side of the box is your network
27
Q
Network Interface Card (NIC)
A
- The fundamental network device
– Every device on the network has a NIC
– Computers, servers, printers, routers, switches, phones, tablets, cameras, etc. - Specific to the network type
– Ethernet, WAN, wireless, etc. - Often built-in to the motherboard
– Or added as an expansion card - Many options - Single port, multi-port, copper, fiber
28
Q
802.11a
A
- Operates in the 5 GHz range
– Or other frequencies with special licensing - 54 megabits per second (Mbit/s)
- Smaller range than 802.11b
– Higher frequency is absorbed by objects in the way
29
Q
802.11b
A
- Operates in the 2.4 GHz range
- 11 megabits per second (Mbit/s)
- Better range than 802.11a, less absorption problems
- More frequency conflict
– Baby monitors, cordless phones, microwave ovens, Bluetooth
