1. Sybex CCENT 640-822 Chapter 8: IP Routing Instructor & Todd Lammle

2. Chapter 8 Objectives Understanding IP routing Static routing Dynamic routing –RIP –RIPv2 –Verifying routing 2

3. To route a router need to know: –Remote Networks –Neighbor Routers –All Possible routes to remote network –The absolute best route to all remote networks –Maintain and verify the routing information What is Routing? CB A D

4. Basic Path Selection What interface will the router send out a packet if it has destination address of 10.10.10.18?

5. Simple IP Routing

6. Routing/PDU Example: Host A Web browses to the HTTP Server….

7. Routing/PDU Example 2

8. ICMP Error example

9. Basic Routing Using MAC and IP Addresses

10. Testing basic routing Knowledge

11. Configuring IP Routing Network

12. ip route remote network [mask] {address|interface} [distance] [permanent] Router(config)#ip route remote_network mask next_hop Static Route Configuration

13. ip route 172.16.1.0 255.255.255.0 172.16.3.2 or ip route 172.16.1.0 255.255.255.0 s0 Static Route Example 172.16.3.2 SO 172.16.1.0 B 172.16.3.1 A B Stub Network 172.16.2.0 SO

14. Default Routes 172.16.3.2 SO 172.16.1.0 B 172.16.3.1 A B Stub Network 172.16.2.0 SO ip route 0.0.0.0 0.0.0.0 172.16.3.1 ip classless

15. Configuring a gateway of Last resort

16. Routing protocols are used between routers to: –Determine the path of a packet through a network –Maintain routing tables –Examples? Routed protocols are: –Assigned to an interface –Once the path is determined by the Routing protocol, determines method of delivery –Examples? Routing vs. Routed

17. Autonomous System 1Autonomous System 2 IGPs: RIP, IGRP EGPs: BGP Routing Protocols An autonomous system is a collection of networks under a common administrative domain. IGPs operate within an autonomous system. EGPs connect different autonomous systems.

18. Classful Routing Overview Classful routing protocols do not include the subnet mask with the route advertisement. –Within the same network, consistency of the subnet masks is assumed. –Summary routes are exchanged between foreign networks. –Examples of classful routing protocols: RIP Version 1 (RIPv1) IGRP

19. Classless Routing Overview Classless routing protocols include the subnet mask with the route advertisement. –Classless routing protocols support variable-length subnet masking (VLSM). –Summary routes can be manually controlled within the network. –Examples of classless routing protocols: RIP Version 2 (RIPv2) EIGRP OSPF IS-IS

20. IGRP Administrative Distance=100 Router D Router B Router A Router C RIP Administrative Distance=120 Default Administrative Distance Directly Connected: 0 Static Route: 1 RIP: 120 IGRP: 100 EIGRP: 90 OSPF: 110 Administrative Distance

21. CB A D Routing Table Routing Table Routing Table Routing Table Routing Table Routing Table Routing Table Routing Table Distance—How far Vector—In which direction Distance vector algorithms do not allow a router to know the exact topology of an internetwork. All routers just broadcast their entire routing table out all active interfaces on periodic time intervals Distance Vector

22. Pinhole Congestion

23. Discovering Routes

24. Converged Routes

25. Routing Loops

26. 64kbps T1 –Hop count metric selects the path, 16 is unreachable –Full route table broadcast every 30 seconds –Load balance maximum of 6 equal cost paths (default = 4) –RIPv2 supports VLSM and Discontiguous networks RIP Overview

27. Router(config)#router rip Router(config-router)#network network-number* network 172.16.0.0 network 192.168.10.0 router RIP network 172.16.0.0 network 10.0.0.0 router RIP *Network is a classful network address. Every device on network uses the same subnet mask 172.16.10.0 192.168.10.0 10.3.5.0 RIP Routing Configuration

28. RIP Routing Example 2

29. RIP Version 2 Allows the use of variable length subnet masks (VLSM) by sending subnet mask information with each route update Distance Vector – same AD, and timers. Easy configuration, just add the command “version 2” under the router rip configuration router rip network 10.0.0.0 version 2

30. Discontiguous Addressing Two networks of the same classful networks are separated by a different network address 192.168.10.0/24 10.1.1.0/24 192.168.10.0/24 –RIPv1 and IGRP do not advertise subnet masks, and therefore cannot support discontiguous subnets. –OSPF, EIGRP, and RIPv2 can advertise subnet masks, and therefore can support discontiguous subnets.

31. A Discontiguous network

32. Verifying RIP Router#show ip protocols Router#show ip route Router#debug ip rip Router#undebug all (un all)

33. Summary –Open your books and go through all the written labs and the review questions. –Review the answers in class. 33