1 Module 03 Routing Protocol Chapter 11 Advanced Routing Protocol Topics 2 Table of Content 1 Route Summarization and Variable-Length Subnet Masks 2 Classless Routing Protocols and Classless Routing 3 1. Route Summarization and Variable-Length Subnet Masks 4 Issues with IP Addressing  IP addressing crisis  As early as 1992, the IETF identified two specific concerns:  IP address exhaustion  Routing table growth U N I V E R S I T Y U N I V E R S I T Y Internet 5 IP Addressing Solutions  Short term to extension to IPv4  Subneting masking: RFCs 950, 1812  Variable-length subnet masks: RFC 1812  Classless interdomain routing: RFCs 1518, 1519, 2050  Address allocation for private Internets: RFC 1918  Network Address Translation: RFC 1631  Route summarization: RFC 1518  Ultimate solution: IPv6 128-bit address space 6 What is VLSM ?  Subnet 172.16.14.0/24 is divided into smaller subnets (Sub- subnet):  Subnet with one mask at first (/27)  Further subnet one of these subnets not used elsewhere (/30) 172.16.0.0/16 172.16.14.32/27 172.16.14. 64/27 172.16.14.96/27 C B A HQ 172.16.1.0/24 172 .16. 2.0/ 24 HQ 172.16.14.136/30 172.16.14.132/30 172.16.14.140/30 7 VLSM is supported  Open Shortest Path First (OSPF).  Integrated Intermediate System to Intermediate System (Integrated IS-IS).  Enhanced Interior Gateway Routing Protocol (EIGRP).  RIP v2.  Static routing. 8 A waste of space 9 When to use VLSM? 10 Calculating subnets with VLSM [...]... Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic... Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic... default-network command R3# show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user... default-network command R1(config)# ip default network 10.0.0.0 R1(config)# exit R1# show ip route Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2,... summarization  Variable-length subnet masking  Classless and classful routing protocols—With classful routing protocols, the routing protocol must consider class rules; classless routing protocols do not Specifically, classful routing protocols must automatically summarize routing information at network boundaries, meaning that they cannot support discontiguous networks Classful routing protocols also cannot... external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area * - candidate default, U - per-user static route, o - ODR P - periodic downloaded static route Gateway of last resort is 168.13.1.101 to network 10.0.0.0 168.13.0.0/24 is subnetted, 5 subnets R 168.13.200.0 [120/1] via 168.13.1.101,... support VLSM Classless routing protocols can support discontiguous networks, and support VLSM  Classless and classful routing With classful routing, the only time the default route is used is when a packet’s destination Class A, B, or C network number is not in the routing table With classless routing, the default is used whenever the packet does not match a more specific route in the routing table 29 ... 192.168.10.96/28 12 Hosts Singapore 192.168.10.112/28 12 Hosts 16 2 CLASSLESS ROUTING PROTOCOLS AND CLASSLESS ROUTING 17 Classless and Classful Routing Protocols  Classful routing protocols do not transmit the mask information along with the subnet number  Classless routing protocols do transmit mask information They support some advanced features such as VLSM and summarization 18 Autosummarization  When... 26 Classless Routing R3# ping 10.1.1.1 Type escape sequence to abort Sending 5, 100-byte ICMP Echos to 10.1.1.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 84/89/114 ms R3# ping 168.13.200.1 Type escape sequence to abort Sending 5, 100-byte ICMP Echos to 168.13.200.1, timeout is 2 seconds: WHY? Success rate is 0 percent (0/5) 27 Classless routing (cont.)... reduces routing table size by aggregating routes to multiple networks into one supernet 14 Route summarization example 15 Configuring VLSM 192.168.10.0/24 192.168.10.64/27 KL 192.168.10.128/30 28 Hosts S0 10.137 192.168.10.136/30 192.168.10.132/30 S0 10.137 Perth 192.168.10.0/26 60 Hosts Sydney 192.168.10.96/28 12 Hosts Singapore 192.168.10.112/28 12 Hosts 16 2 CLASSLESS ROUTING PROTOCOLS AND CLASSLESS ROUTING . 1 Module 03 Routing Protocol Chapter 11 Advanced Routing Protocol Topics 2 Table of Content 1 Route Summarization and Variable-Length Subnet Masks 2 Classless Routing Protocols and. 192.168.10.96/28 S0 10.137 S0 10.137 17 2. CLASSLESS ROUTING PROTOCOLS AND CLASSLESS ROUTING 18 Classless and Classful Routing Protocols  Classful routing protocols do not transmit the mask information. Intermediate System to Intermediate System (Integrated IS-IS).  Enhanced Interior Gateway Routing Protocol (EIGRP).  RIP v2.  Static routing. 8 A waste of space 9 When to use VLSM? 10 Calculating