Routing 2 Chapter 11

Routing 2 Chapter 11 - OSPF CCNA Exploration Semester 2...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
13 May 2009 S Ward Abingdon and Witney College 1 OSPF CCNA Exploration Semester 2 Chapter 11
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 May 2009 S Ward Abingdon and Witney College 2 Topics Background and features of OSPF Configure basic OSPF OSPF metric Designated router/backup designated router elections
Background image of page 2
13 May 2009 S Ward Abingdon and Witney College 3 RIP v1 RIP v2 IGRP EIGRP Routing protocols Interior Exterior Distance vector Link state OSPF IS-IS EGP BGP
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 May 2009 S Ward Abingdon and Witney College 4 OSPF background Developed by IETF to replace RIP Better metric Fast convergence Scales to large networks by using areas
Background image of page 4
13 May 2009 S Ward Abingdon and Witney College 5 Hello, OSPF packet type 1 Discover OSPF neighbours and establish adjacencies. Advertise parameters on which two routers must agree to become neighbours. Elect the Designated Router (DR) and Backup Designated Router (BDR) on multi- access networks like Ethernet and Frame Relay.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 May 2009 S Ward Abingdon and Witney College 6 Sending Hellos By default, OSPF Hello packets are sent every 10 seconds on multi-access and point- to-point segments and every 30 seconds on non-broadcast multi-access (NBMA) segments (Frame Relay, X.25, ATM). In most cases, OSPF Hello packets are sent as multicast to 224.0.0.5. Router waits for Dead interval before declaring the neighbour "down." Default is four times the Hello interval.
Background image of page 6
13 May 2009 S Ward Abingdon and Witney College 7 Matching Before two routers can form an OSPF neighbour adjacency, they must agree on three values: Hello interval, Dead interval, Network type (e.g. point to point, Ethernet, NBMA.)
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 May 2009 S Ward Abingdon and Witney College 8 Election On multi-access networks (Ethernet, NBMA) the routers elect a designated router and a backup designated router This saves on overhead Each router becomes adjacent to the designated router and swaps updates with it If the designated router fails, the backup designated router takes over
Background image of page 8
13 May 2009 S Ward Abingdon and Witney College 9 Finding best routes
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
13 May 2009 S Ward
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 33

Routing 2 Chapter 11 - OSPF CCNA Exploration Semester 2...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online