CompTIA A+ 220-1101 Core 1 Study Flashcards Save

Local Area Network (LAN)

A network that covers a relatively small area such as a building or group of buildings
(1.1 & 2.7)

Personal Area Network (PAN)

• Provides communication for devices owned by a single user that work over a short distance

• Bluetooth

LCD (Liquid Crystal Display)

Lightweight & Inexpensive - Poor black levels due to Separate Backlight
(1.2)

TN (twisted nematic)

Fast response Times - Low cost - Low Power Use - Limited Viewing Angles
(1.2)

IPS (In Plane Switching)

Better Colors - Better Viewing Angles - More Expensive
(1.2)

OLED (organic light-emitting diode)

Thinner & Brighter - No Need for Backlight
(1.2)

MDM (mobile device management)

• Manage company & user devices

• Centralized management system

• Ensures device security (1.4)

MAM (mobile application management)

• Set policies & restrictions on apps

• Control Company software (Update

PRL (Preferred Roaming List)

- Allows phone to connect to the right tower
(1.4)

Port 20/21

FTP (File Transfer Protocol)

• 20(TCP) for Data Transfers

• 21(TCP) to Control Data Transfers (2.1)

Port 22

SSH (Secure Shell) - TCP

• Encrypted Communication

• Looks/Acts the same as Telnet (2.1)

Port 23

Telnet (Telecommunications Network) - TCP

• Non-encrypted Communication

• Log into devices remotely (2.1)

Port 25

SMTP (Simple Mail Transfer Protocol) - TCP
- Used to send mail from device to mail server
(2.1)

Port 53

DNS (Domain Name System) - UDP

• Converts names to IP addresses

• CRITICAL Resource (2.1)

Port 67/68

DHCP (Dynamic Host Configuration Protocol) - UDP

• Automated configuration of IP addresses

• IPs can be reserved for certain devices

• IP Range: 10.1.10.10 through 10.1.10.199 (2.1)

Port 80

HTTP (Hypertext Transfer Protocol) - TCP
- Non-encrypted communication in the browser
(2.1)

Port 110

POP3 (Post Office Protocol 3) - TCP

• Receive emails from an email server

• Basic mail transfer functionality (2.1)

Port 143

IMAP (Internet Mail Access Protocol) - TCP
- Includes management of email inboxes from multiple clients. (Sync email across multiple devices)
(2.1)

Port 161/162

SNMP (Simple Network Management Protocol) - UDP

• Port 161 queries devices for performance statistics.

• Port 162 monitors when metrics exceed a certain threshold. (2.1)

Port 389

LDAP (Lightweight Directory Access Protocol) - TCP

• Store & retrieve info in a network directory.

• Commonly used in Microsoft Active Directory. (2.1)

Port 443

HTTPS (Hyper Text Transfer Protocol Secure) - TCP
- Encrypted Communication in the Browser
(2.1)

Port 445

Server Message Block (SMB) & Common Internet File System (CIFS) - TCP
- Provides direct connection & communication over TCP without the NetBIOS Transport
(2.1)

Port 3389

RDP (Remote Desktop Protocol) - TCP
- Share a desktop from a remote location
(2.1)

Access Point

Extends wired network & converts it into a wireless network.
(2.2)

Router

Routes traffic between IP subnets
(2.2)

Patch Panel

• Goes between work desks & switches

• Work desk connections to patch panel are permanent. (2.2)

Firewalls

-Filters traffic by TCP/UDP port number (OSI Layer 4 filtering)
-Some can filter based on the application
-Can encrypt traffic in/out of the network (protect traffic between sites)
-Can proxy traffic (common security technique)
-Can be used as a Layer 3 device (routers)
(2.2)

PoE (Power over Ethernet)

Devices that send Ethernet data and power over twisted-pair cable to compliant devices (for example

Modem

• Cable Version: Uses DOCSIS (Data over Cable Service Interface Specification) which is broadband.

• DSL Version: Uses ADSL (Asymmetrical Digital Subscriber Line) where download speed is higher than upload speed. (2.2)

ONT (optical network terminal)

• Fiber

• ISP fiber line stretches to demarc point at which your in-home copper wire takes over. (2.2)

NIC (Network Interface Card)

• A device that serves as an interface between the computer and the network. Also called a network adapter or network card.

• Ethernet Connection

• May need drivers installed before hardware is installed (Check Manual) (2.2)

802.11 Types

a (10/1999) - 5Ghz & 54 mbit/s
b (10/1999) - 2.4 Ghz & 11 mbit/s
g (06/2003) - 2.4 Ghz & 54 mbit/s
n (10/2009) - 2.4/5 Ghz & 600 mbit/s
ac (01/2014) - 5 Ghz & Almost 7 Gb/s
ax (02/2021) - 2.4/5 Ghz & About 9.6 Gb/s
(2.3)

DNS Server

• Converts a website name to an IP Addresses

• Usually managed by ISP or enterprise IT Dept. (2.4)

DHCP Server

• The server leases IP addresses to network clients

• IP Range: 10.1.10.10 through 10.1.10.199 (2.4)

File Server

- Centralized Storage of documents

Print Server

• Connect a printer to the network

• Provide printing services for all network devices

• May be built-in to the printer

• Uses standard printing protocols

• SMB (Server Message Block)

Mail Server

- A server that manages the storage and transfer of e-mail messages on a network.
(2.4)

Syslog Server

• A type of server used for collecting system messages from networked devices

• Usually a central logging receiver (2.4)

Web Server

• A server that delivers requested webpages to your computer or mobile device

• Uses HTTPS/HTTPS & HTML/HTML5

• Web pages are stored on the server (2.4)

Authentication Server

• A server that keeps track of who's logging on to the network and which services on the network are available to each user.

• Redundant Server (Always Available) (2.4)

Spam Gateway

• Checks for Unsolicited Emails

• Scans incoming mail to accept or reject it. (2.4)

UTM Gateway (Unified Threat Management Gateway)

Services:

• URL Filter / Content Inspection

• Firewall - Malware Inspection

• Spam Filter - VPN Endpoint

• IDP / IPS (2.4)

Load Balancer

• A dedicated network device that can direct requests to different servers based on a variety of factors.

• Distributes load to multiple servers

• Server outages have no effect

• TCP & SSL Offload (2.4)

Proxy Server

• A server that acts as an intermediary between a user and the Internet.

• Access control

SCADA / ICS (Supervisory Control and Data Acquisition / Industrial Control System)

• Large-scale

• PC Manages Equipment

• Requires extensive segmentation

• Usually expensive software

IoT (Internet of Things)

• Appliances such as fridges & microwaves

• Air control (Smart Thermostats)

• Access Devices (Smart doorbells and locks) (2.4)

IPv4

• The dominant protocol for routing traffic on the Internet

• 4 Numbers (X.X.X.X)

• 32 bits or 4 bytes -> 8 bits per number

• Max value for each number is 255 (2.5)

IPv6 (Internet Protocol version 6)

• 8 hexadecimals (X.X.X.X.X.X.X.X)

• 128 bits or 16 bytes -> 16 bits per number

APIPA (Automatic Private IP Addressing)

• Link Local addresses (no router forwarding)

• IETF has reserved 169.254.0.0 - 169.254.255.255

• Only communicates on your network (2.5)

Static IP

- An IP address that is manually assigned to a device and remains constant until it is manually changed.
(2.5)

Dynamic IP

• IP address assigned by DHCP server.

• This method insures there are no overlapping IP addresses within a network.

• Changes when lease expires (2.5)

Gateway

- A node that handles communication between its LAN and other networks.
(2.5)

DNS Configuration

- 13 root server clusters (Over 1

Address Records

• A records are for IPv4 addresses

• AAAA records are for IPv6 addresses (2.6)

MX (Mail Exchanger)

- Determines host name for mail server
(2.6)

TXT (Text Records)

• Can be used for verification purposes

• Commonly used for email security

• External email servers validate info from your DNS. (2.6)

Spam Management

• - Domain Keys Identified Mail (DKIM)

  - Digitally sign a domains outgoing mail

  - Public key is available in DKIM TXT record

  - Sender Policy Framework (SPF)

  - List of all servers authorized to send emails on behalf of this domain; prevents email spoofing

  - Mail server validates mail is coming from authorized host

  - Domain-based Message Authentication, Reporting, & Conformance (DMARC)

  - Extension of DKIM / SPF

  - Decides what servers do with mail that isn't accepted by SPF/DKIM

  (2.6)

Lease

- Created by the DHCP server to allow a system requesting an IP to use that IP for a certain amount of time.
(2.6)

Reservation

- An IP address that is set aside by a DHCP server for a specific network client

Scope

- The predefined range of addresses that can be leased to any network device on a particular network.
(2.6)

VLAN (Virtual Local Area Network)

• Separated logically instead of physically

• Multiple domains under one physical switch (2.6)

VPN (Virtual Private Network)

- Concentrator
- Encryption/Decryption access device
- Actively encrypts & decrypts your data packets
(2.6)

Satellite Networking

• Non-terrestrial communication

• 50 Mbit/s down

Fiber Newtwork

• High Speed Communication

• Higher install costs vs copper wire

• Large installation in the WAN core

• Supports high data rates

• SONET

Cable

• Broadband (Transmission across many multiple frequencies)

• Data on "cable" network

• DOCSIS

• High Speed (50-1000 Mbit/s) (2.7)

DSL

• ADSL (Assymetrical Digital Subscriber Line)

• 200 Mb down and 20 Mb up is common (2.7)

Cellular Network

• Separates land into "cells" and each cell covers a different frequency

• Tethering (Turn your phone into a router)

• Mobile Hotspot (2.7)

WISP

• Wireless Internet Service Provider

• Connects rural/remote locations

• Need an outdoor antenna to connect typically (2.7)

WAN (Wide Area Network)

• Generally connects LANs across a distance

• Many different technologies

• Point-to-point Serial

MAN (Metropolitan Area Network)

• A network covering a city

• Bigger than LAN

SAN (Storage Area Network)

• Looks & feels like a local storage device

• Requires high bandwidth

• Some people may use an isolated network solely for the SAN (2.7)

WLAN (Wireless Local Area Network)

• A self-contained network of two or more computers connected using a wireless connection.

• Usually within a building (2.7)

Cable Crimpers

- "Pinch" the connector onto a wire
- Coaxial

WiFi Analyzer

• Everyone "hears" everything

• Specializes in 802.11 analysis

• Identify errors and interference

• Validate antenna location and installation (2.8)

Tone Generator / Probe

• Tone generator

• Sends an analog sound through the cable it is attached to

• Probe

• Makes noise and/or lights up when touching the cable with the generator attached

• Easy wire tracing (2.8)

Punch Down Tool

• A pointed tool used to insert twisted-pair wire into receptors in a punch-down block

• Organization is key

• Maintain twists in cables (2.8)

Cable Testers

• Continuity test

• Can identify missing pins or crossed wires

• Not usually used for frequency testing (2.8)

Loopback Plug

- Useful for testing physical ports
- Serial

Taps & Port Mirrors

• Used to intercept network traffic

• Physical Taps

• Disconnect link & put tap in the middle

• Active or Passive Tap

• Port Mirror

• Software based tap

• SPAN (Switched Port ANalyzer)

• Limited Functionality (2.8)

Cat 5 & Cat 5e (enhanced)

• Cable used to connect a network infrastructure

• 1000Base-T Ethernet Standard

• Work up to 100 meters (3.1)

Cat 6 & Cat 6a (Augmented)

• Use 10GBase-T Ethernet Standard

• Unshielded Cat 6 works up to 55 meters

• Shielded Cat 6 and Cat 6a work up to 100 meters (3.1)

Coaxial

• Single copper wire cable surrounded in layers

• Uses RG-6 connector

• Commonly used in TV's and High-Speed internet over cable (3.1)

STP (Shielded Twisted Pair)

- A type of cable containing twisted-wire pairs that are not only individually insulated

UTP (Unshielded Twisted Pair)

• Composed of pairs of wires twisted around each other at specific intervals.

• No additional shielding around pairs of wires (3.1)

Direct Burial STP

• Protected from elements

• Cable is buried in the ground

• Often filled with gel to repel water

• Shielding in the STP protects against interference (3.1)

Plenum

• The area above the ceiling tile for the HVAC system and usually network wires to run

• Traditional cable is Polyvinyl Chloride (PVC) and not safe against fires

• Fire Rated Cable Jackets to use in a Plenum:

• Fluorinated Ethylene Polymer (FEP)

• Low-Smoke PVC (3.1)

Fiber

• Transmission by light - No RF signals

• Difficult to monitor & tap

• Multimode: Short Range Communication (2km) - Uses Cheaper LED's

• Single Mode: Long Range Comm. (100km) - Uses Expensive Lasers (3.1)

T568A & T568B

• The two color codes used for wiring eight-position RJ45 modular plugs.

• Neither is better than the other

• Many organizations typically use T568B (3.1)

USB 2.0

• HighSpeed: 480 megabits per second

• 5 meters max length (3.1)

USB 3.0

• SuperSpeed: 5 gigabits per second

• 3 meters (No specified Length) (3.1)

Serial (Console Cable)

• Used to configure telephone and networking equipment

• Commonly used for RS-232 (3.1)

Thunderbolt Cable

• High-speed serial connector

• Thunderbolt v2 -20 Gbit/s aggregated channels -Mini DisplayPort connector

• Thunderbolt v3 -40 Gbit/s aggregated throughput -USB-C connector

• 3 meters w/ copper

HDMI (High-Definition Multimedia Interface)

• Digital audio and video interface

• 19-pin type a connector

• Around a 20 meter range (3.1)

DisplayPort

• Digital video connector in packetized form

• Carries audio and video

• Compatible with HDMI & DVI (With an adapter) (3.1)

DVI (Digital Visual Interface)

• Single & Dual link video

• Single = 3.7 GB/s &. Dual = 7.4 GB/s

• DVI-A (Analog)

• DVI-D (Digital)

• DVI-I (Integrated) - Analog and Digital (3.1)

VGA (Video Graphics Array)

-DB-15 connector (Also known as DE-15)
-Blue color
-Analog signal (No digital option)
-Image degrades after 5 to 10 meters
(3.1)

SATA (Serial Advanced Technology Attachment)

• Uses serial signals to transfer data

• SATA 3.0 (6 GB/s)

• SATA 3.2 (16 GB/s)

SCSI (Small Computer System Interface)

• Designed to string up to 16 devices on one cable

• LUN (Logical Unit) are defined within each SCSI ID

• SAS (Serial Attached SCSI) devices have no jumpers

eSATA (External SATA)

- A modern type of connector for attaching external hard disks
(3.1)

IDE (Integrated Drive Electronics)

- A hard drive whose disk controller is integrated into the drive