CompTIA A+ 220-1101 Core 1 Study Flashcards

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, IR, NFC, etc.

(1.1 & 2.7)

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, Remove, Etc.)

(1.4)

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, cameras, phones, etc).

(2.2)

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, files, etc.

- Standard system of file management

- SMB (Server Message Block)

- AFP (Apple Filing Protocol)

(2.4)

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),

- IPP (Internet Printing Protocol),

- LPD (Line Printer Daemon)

(2.4)

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, URL Filtering, Content Scanning

(2.4)

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

- Large-scale

- PC Manages Equipment

- Requires extensive segmentation

- Usually expensive software, requires elevated permission to access.

(2.4)

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 1,000 actual servers)

- 100's of Generic Top Level Domains (gTLD)

- Over 275 Country-Code Top-Level Domains (ccTLD)

(2.6)

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, which is identified by its MAC address.

(2.6)

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, 3 Mbit/s up

- High latency (250 ms up/down)

- High frequencies (2 GHz)

(2.7)

Fiber Newtwork

- High Speed Communication

- Higher install costs vs copper wire

- Large installation in the WAN core

- Supports high data rates

- SONET, Wavelength Division Multiplexing

(2.7)

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, MPLS, etc.

(2.7)

MAN (Metropolitan Area Network)

- A network covering a city

- Bigger than LAN, usually smaller than WAN

- Common to see government ownership

(2.7)

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, twisted pair, fiber

- Connect the modular connector to the Ethernet cable

- Metal prongs are pushed through the insulation

(2.8)

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, Ethernet, T1, fiber

- Data leaves the interface, loops back, and reenters

(2.8)

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, but also surrounded by a shielding.

- Requires the cable to be grounded via an additional wire in the cable

(3.1)

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, 60 meters w/ optical

(3.1)

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, terminators, or settings

- SCSI pronounced "scuzzy"

(3.1)

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, eliminating the need for a controller cable and thus increasing speed

- Originally called PATA (Parallel AT Attachment)

(3.1)