2.1 Routing Technologies

Routing Tables

A map of forwarding locations stored on every IP device

Static Routing

Manually creating and managing routing tables

Dynamic Routing

A router sends it’s routing table to other routers, creating routing tables that update in real time as the network changes

Dynamic Routing Protocols

Protocols used by routers to listen for dynamic routing requests then determine the best path for requests based on information received

EIGRP

Enhanced Interior Gateway Routing Protocol

• Proprietary to Cisco devices

• Manages topology changes

• Distance Vector Protocol

OSPF

Open Shortest Path First

• A common generic routing protocol

• Often used within a single AS

• Link state protocol

Link State Protocol

Routing is based on connectivity between routers.

Each link is assigned a cost and the path with the lowest cost is the fastest

BGP

Border Gateway Protocol

• Exterior gateway protocol

  • Connects different ASs

• A popular standard for internet routing

Administrative Distances

Uses by the router to determine which protocol has priority

FHRP

First Hop Redundancy Protocol

• Allows routers to pass virtual IPs between each other so if one router fails another will take it’s place

Sub Interface

Allows a single physical interface to register as multiple interfaces virtually

NAT

Network Address Translation

• Converts IPv6 addresses into virtual IPv4 addresses to allow communication between IPv6 addresses and IPv4 devices

RIP

Routing Information Protocol

• One of the oldest protocols, commonly used in smaller networks.

• It uses hop count as its metric, with a maximum limit of 15 hops to prevent routing loops

• Distance Vector Protocol