1 / 30

Routing Algorithm

www.btechebooks4u.blogspot.com. Routing Algorithm. Your Text Here. 2004. 11. 3 Ahn Kook Jin. www.btechebooks4u.blogspot.com. Contents. Routing Protocol and Algorithm Classifications Link State Routing Algorithm Distance Vector Routing Algorithm LS Algorithm vs. DV Algorithm

adrian-hogan
Télécharger la présentation

Routing Algorithm

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. www.btechebooks4u.blogspot.com Routing Algorithm Your Text Here 2004. 11. 3 Ahn Kook Jin

  2. www.btechebooks4u.blogspot.com Contents • Routing Protocol and Algorithm • Classifications • Link State Routing Algorithm • Distance Vector Routing Algorithm • LS Algorithm vs. DV Algorithm • Hierarchical Routing

  3. destination router 5 first-hop routerdefault router 3 B D 2 5 2 3 1 F A 1 1 2 C E least-cost path source router Routing Protocol and Algorithm • Determining the path(route) destination host source host www.btechebooks4u.blogspot.com

  4. www.btechebooks4u.blogspot.com Classifications • Global vs. decentralized • global(link state algorithm) : complete information about connectivity and link costs • Static vs. dynamic • static : routes change very slowly • Load-sensitive vs. load-insensitive • load-sensitive : link costs reflect congestion • Typical used • Dynamic link state routing algorithm • Dynamic distance vector routing algorithm

  5. Link State Routing Algorithm • Each node broadcasts the identities and costs to its directly attached neighbors • Dijkstra’s algorithm www.btechebooks4u.blogspot.com

  6. 1 2+e 0 2+e 0 0 0 0 0 0 0 0 0 2+e 0 1+e A C B D 1 1 1+e 0 0 1+e 1 1 0 0 0 0 1 0 e 0 1+e 0 e Link State Routing Algorithm • Oscillation(page 307) www.btechebooks4u.blogspot.com

  7. Distance Vector Routing Algorithm • Iterative, asynchronous, distributed • Distance table • DX(Y,Z) : cost of the direct link from X to Z + Z’s currently known minmum-cost path to Y • DX(Y,Z)=c(X,Z)+minw{Dz(Y,w)} www.btechebooks4u.blogspot.com

  8. Distance Vector Routing Algorithm • Initialization: • DX(*,v) = inifinite, DX(v,v)=c(x,v) • Send minwDX(y,w) to each neighbor when they changes • C(X,V) changes • Neighbor node send its update www.btechebooks4u.blogspot.com

  9. Y X Z Distance Vector Routing Algorithm 2 1 7 www.btechebooks4u.blogspot.com

  10. Y X Z Distance Vector Routing Algorithm 2 1 7

  11. Y X Z Distance Vector Routing Algorithm 2 1 7

  12. Y X Z Distance Vector Routing Algorithm • Decrease 1 4 1 50

  13. Y X Z Distance Vector Routing Algorithm • Decrease 1 4 1 50

  14. Y X Z Distance Vector Routing Algorithm • Decrease 1 4 1 50

  15. Y X Z Distance Vector Routing Algorithm • Decrease 1 4 1 50

  16. Y X Z Distance Vector Routing Algorithm • Increase 60 4 1 50

  17. Y X Z Distance Vector Routing Algorithm • Increase 60 4 1 Routing loop 50

  18. Y X Z Distance Vector Routing Algorithm • Increase 60 4 1 50

  19. Y X Z Distance Vector Routing Algorithm • Increase 60 4 1 50

  20. Y X Z Distance Vector Routing Algorithm • Increase 60 4 1 Too many iterations! (count-to-infinity problem) 50

  21. Y X Z Distance Vector Routing Algorithm • Poisoned reverse 60 4 1 50

  22. Y X Z Distance Vector Routing Algorithm • Poisoned reverse 60 4 1 50

  23. Y X Z Distance Vector Routing Algorithm • Poisoned reverse 60 4 1 50

  24. Y X Z Distance Vector Routing Algorithm • Poisoned reverse 60 4 1 50

  25. Y X Z Distance Vector Routing Algorithm • Poisoned reverse • Cannot solve general count-to-infinity problem 60 4 1 50

  26. LS Algorithm vs. DV Algorithm

  27. Hierarchical Routing • View network as interconnected routers • Scale • Administrative autonomy • Organize routers into autonomy systems(AS)

  28. B.a C.a A.a B.a A.b A.d C.b C.c Host H1 A.c Host H2 Hierarchical Routing Autonomy system(AS)Gateway routerIntra-ASInter-AS

  29. B.a A.a A.c C.a Hierarchical Routing Topological view for inter-AS routing protocol

  30. END Download more ebooks @ www.btechebooks4u.blogspot.com

More Related