Shulou(Shulou.com)06/01 Report--

Use area benefits:

* A router only needs to have the same link-state database as other routers in its area, and there is no need to share the same link-state database with all routers in the entire OSPF area, so the indentation of the link-state database reduces the consumption of router memory.

* reducing the link-state database means processing less LSA and reducing the router's CPU consumption

* because link-state databases need to be maintained in only one area, a large number of LSA flooding spreads are limited to one area

Regions are identified by a 32-bit region ID

Representation:

Decimal number or dotted decimal

Area0 and area0.0.0.0 are the same.

Three kinds of area-related traffic

Intra-domain traffic Intra-Area Traffic

Traffic consisting of packets exchanged between routers in a single domain

Inter-domain traffic Inter-Area Traffic

Traffic made up of packets exchanged between routers in different areas

External traffic External Traffic

Traffic made up of packets exchanged between routers in an OSPF domain and routers in other routing domains

Area 0 is the area number reserved for the backbone area

The task of the backbone domain is to summarize the network topology of each area to all other areas, so all inter-domain traffic must pass through the backbone domain, and packets cannot be exchanged directly between non-backbone domains.

1. Router Typ

Internal router Internal Router

All interfaces belong to routers in the same area

Area Border Router Area Border Router ABR

Routers that connect one or more areas to the backbone area and act as router gateways for interdomain traffic

At least one interface of ABR belongs to the backbone area, and a different link-state database must be maintained for each area connected to it.

Backbone router Backbone Router

At least one interface is a router connected to the backbone area, which means that ABR can also be a backbone router

Autonomous system Border Router Autonomous System Boundary Router ASBR

Traffic from outside the OSPF domain enters the gateway router of the OSPF domain

two。 Segmented region

A situation in which one part of an area is isolated from other parts due to link failure

3. Virtual link

A link that connects to a backbone area through a non-backbone area.

Function:

(1) connect a region to a backbone region through a non-backbone area

(2) connect to a partial area on both sides of a segmented backbone area through a non-backbone area.

Virtual Link configuration rules:

* the virtual link must be configured between two ABR

* the area through which the virtual link is configured must have all the router selection information, which is also known as the transport area.

* transfer area cannot be a stub area

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.