CompTIA A+ Core 1 Part 3

Asymmetric DSL (ADSL)

Has different speeds of download and upload

• Download Speed: 8 Mbps and Upload Speed: 1.544 Mbps

Symmetric DSL (SDSL)

Has equal speeds of download and upload

Very High Bit-Rate DSL (VDSL)

Has high speeds of download and upload

• Download speed 50 Mbps or more and Upload Speed 10 Mbps or more

Cable Modems

Uses a cable TV network that is made up of a hybrid fiber-coaxial (HFC) distribution network.

• Data-Over-Cable Service Interface Specification (DOCSIS)

• transmit and receive over cable television infrastructure

Data-Over-Cable Service Interface Specification (DOCSIS)

Specific frequency ranges used for upstream and downstream transmissions.

Fiber To The Curb (FTTC)

Runs a fiber optic cable from an Internet provider access point to a curb

Fiber To The Premises (FTTP)

Fiber optic that connects directly to a building and connects to an optical network terminal (ONT)

Optical Network Terminal (ONT)

Physical devices that convert optical signals to electrical signals

The _________, the newer the standard, and the more increased the speeds are.

5G comes in three different band: Low-band, Mid-band, High-band

higher the G

Microwave

Uses a beam of radio waves in the microwave frequency range to transmit information between two fixed locations

Satellite

A method of using communication satellites located in space to connect a user to the Internet

Multicast Address

A logical identifier for a group of hosts in a computer network

(I send a message to one person and it goes to multiple people at the same time)

Class A Private IP addresses

10 / 10.0.0.0 - 10.255.255.255

Class B Private IP addresses

172.16-172.31 / 172.16.0.0 - 172.31.255.255

Class C Private IP addresses

192.168 / 192.168.0.0 - 192.168.255.255

Class A: 1st Octet Value, Default Subnet Mask, Possible Hosts

1-127

255.0.0.0

256x256x256= 16.7 million

Class B: 1st Octet Value, Default Subnet Mask, Possible Hosts

128-191

255.255.0.0

256x256= 65,536

Class C: 1st Octet Value, Default Subnet Mask, Possible Hosts

192-223

255.255.255.0

256

Class D: 1st Octet Value, Default Subnet Mask, Possible Hosts

Reserved for Multicasting or Multicast routing

224-239	-	-

Class E: 1st Octet Value, Default Subnet Mask, Possible Hosts

Reserved for experimental purpose or research and study only

240-255

-

268 million (reserved)

Classful Mask

Default subnet mask for a given class of IP addresses

EX: 192.168.1.4 and 255.255.255.0

Classless Inter-Domain Routing (CIDR)

Allows for borrowing some of the host bits and reassigning them to the network portion.

• Cut down the size of the networks in much smaller portions with less hosts and more efficient.

• Subnetting allows you to use a classless subnet mask to create smaller networks with fewer hosts in each of those networks than you could if you had a classful subnet mask by itself.

Public (Routable)

Can be accessed over the Internet and is assigned to the network by an Internet service provider.

• Running a web server for a company or Minecraft server

Private (Non-Routable)

Can be used by anyone any time, but only within their own local area network.

• ______ ranges include those that start with either 10, 172, or 192

Network Address Translation (NAT)

allows router to changes private IPs into public IP to get internet

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.

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

• 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

Static Assignment

Manually type the IP addresses for the host, its subnet mask, default gateway, and DNS server.

• ________ of IP addresses is impractical on large enterprise networks

Dynamic allocation of IP addresses

Dynamic Assignment

Bootstrap Protocol (BOOTP)

Dynamically assign IP addresses and allows a workstation to load a copy of boot image to the network

• The Oldest

Dynamic Host Control Protocol (DHCP)

Assigns an IP based on an assignable scope or addresses and provides the ability to configure other options within it.

• Can assign and lease IP addresses for a period of time and returns to the pool when the lease expires.

• The IP Address Management manages the IPs being assigned and returned over time

• Provides IP address, Subnet mask, Default gateway, DNS/WINS server

• Modern implementation of BOOTP

Zero Configuration (ZeroConf)

New technology that provides the same features as APIPA

• Can assign an IPv4 link-local address to a client

• Resolve computer names to IP addresses without the need for DNS by using mDNS

• Perform service discovery on a network

Domain Name System (DNS)

Converts the domain names used by a website to the IP address of its server so the device can connect to it.

• DNS is the internet version of a phone book where we can look a name and get a number to connect to

Windows Internet Name Service (WINS)

Identifies NetBIOS systems on a TCP/IP network and converts those NetBIOS names to IP addresses

• Is like DNS but works in Windows Domain Environment

DNS Record	Description
A	Address

Function

(Are used for domain names with IPv4 address)

DNS Record	Description
AAAA	Address

Function

(Are used for domain names with IPv6 address)

DNS Record	Description
CNAME	Canonical Name

Function

(Are used to map domain name to other domain names)

DNS Record	Description
MX	Mail Exchange

Function

(Are used for email)

DNS Record	Description
TXT	Text

Function

(Store text either human-readable or machine-readable data)

DNS Record	Description
NS	Nameserver

Function

(Are used for nameservers)

Virtual Local Area Network (VLAN)

Allow different logical networks to share the same physical hardware and provides added security and efficiency

• Great for security and if using VLAN trunking 802.1q is your standard for VLANs

Virtual Private Network (VPN)

Extends a private network across a public network and enables sending and receiving data across shared or public networks

Full Tunnel VPN

Routes and encrypts all network requests through the VPN connection back to the headquarters

• Security

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.

• Performance

Site-to-site VPN

connects multiple networks, like branch offices or data centers, via the internet.

Client-to-site VPN

links one device (e.g., laptop or smartphone) to a distant network, like a corporate or cloud network.

Clientless VPN

Creates a secure remote-access VPN tunnel using a web browser without requiring a software or hardware client.

Transport Layer Security (TLS)

Provides secure web browsing over HTTPS

Dual Stack

Simultaneously runs both the IPv4 and IPv6 protocols on the same network devices

Tunneling

Allows an existing IPv4 router to carry IPv6 traffic

2018:0000:0000:0000:0000:0000:4815:54ae

2018::4815:54ae

Which of the following is an IPv6 address?

• 192.168.1.1

• 12:34:56:78:90:AB

• 1234::5678:90AB

1234::5678:90AB

Unicast Address

Used to identify a single interface

• Globally-Routed- Similar to IPv4’s unicast class A,B, and C addresses and begins with 2000-3999

• Link-Local/Local Use- Used like a private IP in IPv4 that can only be used on the local area network and begins with FE80

• Stateless Address Autoconfiguration (SLAAC)- Eliminates the need to obtain addresses or other configuration information from a central server

Multicast Address IPv6

Used to identify a set of interfaces and begins with FF

Anycast Address

Used to identify a set of interfaces so that a packet can be sent to any member of a set

Extended Unique Identifier (EUI)

Allows a host to assign itself a unique 64-bit IPv6 interface identifier called EUI-64

DHCPv6 Protocol

Allows DHCP to automatically assign addresses from a DHCPv6 server

Neighbor Discovery Protocol (NDP)

Used to determine the Layer 2 addresses that are on a given network