9) IP Routing

Vocabulary flashcards covering routing types, protocols, selection criteria, and address translation from the CompTIA Network+ N10-009 curriculum.

Routing

The process of selecting paths in a network along which to send network traffic using routers, routing tables, and algorithms.

Static Routing

A manual configuration of routers with specific paths to reach network destinations; simple for small networks but lacks flexibility.

Dynamic Routing

A process where routers communicate via protocols to automatically adjust paths based on network topology and traffic conditions.

Interior Gateway Protocols (IGP)

Routing protocols used by organizations to route between LANs within their own locations, such as connecting different branch offices.

Exterior Gateway Protocols (EGP)

Routing protocols used to route between different organizations' WAN links, such as across the Internet.

Border Gateway Protocol (BGP)

The only EGP protocol used to route the Internet; it uses path attributes and TCP for reliable communication.

Autonomous System (AS)

The collection of an organization's interconnected network locations.

Distance-vector

A hops-based routing protocol type that forwards packets using the path with the fewest number of hops.

Link-state

A bandwidth-based routing protocol type that forwards packets using the path with the highest bandwidth.

Routing Information Protocol (RIP)

A distance-vector protocol using hop count as a metric, with a maximum limit of $15$ hops.

RIPv1

A classful version of RIP that contains no subnet information.

RIPv2

A classless version of RIP that supports subnetting, includes subnet masks, and uses multicast updates.

Open Shortest Path First (OSPF)

A link-state routing protocol featuring hierarchical design with areas, fast convergence, and support for VLSM and CIDR.

Enhanced Interior Gateway Routing Protocol (EIGRP)

An enhanced distance-vector protocol that uses metrics such as bandwidth, delay, load, and reliability.

Metric

A value used by routing protocols to evaluate the cost of path traversal, where lower values are typically more desirable.

Administrative Distance

A metric ranging from $0$ to $255$ used by routers to rank the trustworthiness of routes from different sources; lower values are preferred.

Administrative Distance: Connected interface

$$0$$

Administrative Distance: Static route

$$1$$

Administrative Distance: OSPF

$$110$$

Prefix Length

The number of contiguous bits of the network mask that are set to $1$, such as $/26$ in the address $192.168.20.0/26$.

First-Hop Redundancy Protocols (FHRPs)

Protocols used to achieve high availability by using multiple physical redundant routers.

Hot Standby Router Protocol (HSRP)

A Cisco proprietary redundancy protocol used for first-hop redundancy.

Virtual Router Redundancy Protocol (VRRP)

An open standard redundancy protocol used for first-hop redundancy.

Virtual IP (VIP)

An IP address not tied to a specific physical interface, used for redundancy and load balancing among multiple servers.

Subinterface

A virtual interface created by dividing a single physical interface into multiple logical interfaces to manage VLAN traffic segregation.

Network Address Translation (NAT)

The process of translating one IP address to another, performed by routers or firewalls to conserve public IP addresses.

Static NAT

A one-to-one translation of an internal address to an external address, required for internal hosts to be accessible from the Internet.

Dynamic NAT

A many-to-many translation that can limit internet access and is not commonly used.

Port Address Translation (PAT)

A many-to-one translation also known as overloading NAT or PNAT; it is the most common method for accessing the Internet.