1 / 82

Routing Protocols

Chapter 14. Routing Protocols. RIP, OSPF, BGP. Figure 14-1. Autonomous systems. Figure 14-2. Popular routing protocols. Link State. Distance Vector. Path Vector. Distance Vector Routing. Forouzan + CCNA: Slow convergence. Routing loops. Counting to infinity. Split horizon

Download Presentation

Routing Protocols

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chapter 14 Routing Protocols RIP, OSPF, BGP

  2. Figure 14-1 Autonomous systems

  3. Figure 14-2 Popular routing protocols Link State Distance Vector Path Vector

  4. Distance Vector Routing. Forouzan + CCNA: • Slow convergence. • Routing loops. • Counting to infinity. • Split horizon • Route poisoning. • Triggered update.

  5. 14.3 RIP: Routing Information Protocol Exposición equipo 5

  6. Example of updating a routing

  7. Initial routing tables in a small autonomous system

  8. Final routing tables for the previous figure

  9. RIP message format

  10. Request messages

  11. Example 1 What is the periodic response sent by router R1 in Figure 13.8 (next slide)? Assume R1 knows about the whole autonomous system.

  12. Example 1

  13. Solution R1 can advertise three networks 144.2.7.0, 144.2.9.0, and 144.2.12.0. The periodic response (update packet) is shown in Figure 13.9 (next slide).

  14. Solution to Example 1

  15. RIP timers

  16. Example 2 A routing table has 20 entries. It does not receive information about five routes for 200 seconds. How many timers are running at this time?

  17. Solution The timers are listed below: Periodic timer: 1 Expiration timer: 20 - 5 = 15 Garbage collection timer: 5

  18. Slow convergence

  19. Hop count

  20. Instability

  21. Split horizon

  22. Poison reverse

  23. RIP-v2 Format

  24. RIP version 2 supports CIDR.

  25. Authentication

  26. RIP uses the services of UDP on well-known port 520.

  27. 14.5 OSPF: Open Shortest Path First

  28. Areas in an autonomous system

  29. Types of links

  30. Point-to-point link

  31. Transient link

  32. Stub link

  33. Example of an internet

  34. Graphical representation of an internet

  35. Types of LSAs

  36. Router link

  37. Network link

  38. Summary link to network

  39. Summary link to AS boundary router

  40. External link

  41. Example 3 In Figure 14.31 (next slide), which router(s) sends out router link LSAs?

  42. Figure 14-31 Example 3 and Example 4

  43. Solution All routers advertise router link LSAs. R1 has two links, Net1 and Net2. R2 has one link, Net2 in this AS. R3 has two links, Net2 and Net3.

  44. Example 4 In Figure 14.31, which router(s) sends out the network link LSAs?

  45. Solution All three network must advertise network links: Advertisement for Net1 is done by R1 because it is the only router and therefore the designated router. Advertisement for Net2 can be done by either R1, R2, or R3, depending on which one is chosen as the designated router. Advertisement for Net3 is done by R3 because it is the only router and therefore the designated router.

  46. In OSPF, all routers have the same link state database.

  47. Shortest path calculation Dijkstra algorithm Start Set root to local node and move it to tentative list Tentative list is empty? Yes No Among nodes in tentative list, move the one with the shortest path to permanent list. Add each unprocessed neighbor of last moved node to tentative list if not already There. If neighbor is in the tentative list with larger cumulative cost, replace with new one. Stop

  48. Shortest path calculation Dijkstra algorithm

  49. 0 F

  50. 0 F 5 9 N5 N3

More Related