IS3120 Network Communications Infrastructure Unit 8 Distance Vector IP Routing,, WANs, and Classful IP Routing

Class Agenda 5/6/16 Cover Chapter 11 of Text book Learning Objectives Lesson Presentation and Discussions. Discussion on Assignments. Discussion on Lab Activities. Break Times as per School Regulations. Unit 8 Quiz 4

Learning Objective Design and configure distance vector routing protocols to meet business objectives.

Key Concepts Classful IP routing Distance vector routing protocols 9/17/2018 Key Concepts Classful IP routing Distance vector routing protocols RIP, RIPv2, EIGRP Distance vector IP routed networks design RIP, RIPv2, and EIGRP IP routing and classful IP routing configuration (c) ITT Educational Services, Inc.

9/17/2018 EXPLORE: CONCEPTS (c) ITT Educational Services, Inc.

Distance Vector Routing Protocols 9/17/2018 Distance Vector Routing Protocols Network A Network B 1 Hop Network C 2 Hops Distance routing protocols inform every router they are connected to about each of the networks they are connected to as well as the networks their other neighbors are connected to. Distance is measured by the number of routers, or hops, required to reach another network. Common distance routing protocols are RIP, RIPv2, and EIGRP. RIP and RIPv2 both have a maximum hop limit of 15 to prevent routing loops while EIGRP has a configurable limit up to 255 with a default of 100. (c) ITT Educational Services, Inc.

RIP / RIPv2 Advantages Disadvantages Slow convergence 9/17/2018 RIP / RIPv2 Advantages Disadvantages Doesn’t scale High bandwidth needs Limited hop count Slow convergence Simple to implement Low RAM/CPU needs RIPv1/RIPv2 update their routing table every 30 seconds with information from their neighboring routes. Routing table is rebuilt with new information each time. Routers can only see their neighbors. It can take 7 minutes for a network change to propagate throughout an internetwork (15 hops / 30 seconds). All neighbor routes are equal, regardless of bandwidth of links. RIPv2 supports variable-length subnet masks and classless inter domain routing. (c) ITT Educational Services, Inc.

EIGRP Disadvantages Advantages Higher allowed hop count 9/17/2018 EIGRP Disadvantages Advantages Higher allowed hop count Quick convergence Multiple metric for each count Doesn’t scale to large networks Proprietary protocol EIGRP was designed by Cisco Systems to allow bandwidth, delay, load, MTU, and reliability into the equation when calculating distance. Limitation of 15 hops was increased to 255 although 100 hops was kept as the default. Easy to configure and maintain for small networks but doesn’t scale to large networks. Proprietary protocol only works on Cisco Systems routers. RIPv1 is defined in RFC 1058. RIPv2 is defined in RFC 2453. (c) ITT Educational Services, Inc.

Classful IP Routing Class E 1111 Class D 1110 Class C 110 Class B 10 9/17/2018 Classful IP Routing Class A 0 Class B 10 Class C 110 Class D 1110 Class E 1111 Classful routing is based on the most-significant bits of an IP address. No subnet mask is used. The Class ID defines the bits used for the Network ID. Class A – 128 (2^7) networks with 16,777,216 (2^24) addresses available. 0.0.0.0 – 127.255.255.255 Class B – 16,384 (2^14) networks with 65,536 (2^16) addresses available 128.0.0.0 – 191.255.255.255 Class C – 2,097,152 (2^21) networks with 256 (2^8) address available. 192.0.0.0 – 223.255.255.255 Class D – Multicast network. No defined networks or addresses. 224.0.0.0 – 239.255.255.255 Class E – Reserved. No defined networks or addresses. 240.0.0.0 – 255.255.255.255 Distance vector routing protocols are classful routing protocols. No support of Variable Length Subnet Mask (VLSM) and Classless Inter Domain Routing (CIDR). Classful routing protocol examples: Routing Information Protocol version 1 (RIPv1) and Interior Gateway Routing Protocol (IGRP) Classful routing is a consequence of the fact that routing masks are not advertised in the periodic, routine, routing advertisements generated by distance vector routing protocols. Class ID (c) ITT Educational Services, Inc.

9/17/2018 EXPLORE: PROCESSES (c) ITT Educational Services, Inc.

Distance Vector Routing Design 9/17/2018 Distance Vector Routing Design Routing Protocol Scalability Stability of Connection Manageability Bandwidth Usage Scalability – Current and future size of internetwork. Stability of connection – Is the connection between two routers always on? Is it a dial-on-demand connection? Manageability – How easy is it to build the internetwork and add or remove networks? Bandwidth Usage – How well does the protocol utilize the available bandwidth? (c) ITT Educational Services, Inc.

9/17/2018 EXPLORE: ROLES (c) ITT Educational Services, Inc.

9/17/2018 RIP, RIPv2, and EIGRP Dynamically allow two or more networks to learn about each other Easily managed Low processing and memory requirements (c) ITT Educational Services, Inc.

RIP Entire routing table exchanged Updates sent every 30 seconds 9/17/2018 RIP Entire routing table exchanged Updates sent every 30 seconds Limited to 15 hops All devices must inspect routing packet Slow convergence of network changes Two message types – Request and Response Updates sent every 30 seconds means the network is flooded. RIP packets sent out via broadcast means all devices must inspect packet. (c) ITT Educational Services, Inc.

RIPv2 Entire routing table exchanged Updates sent every 30 seconds 9/17/2018 RIPv2 Entire routing table exchanged Updates sent every 30 seconds Limited to 15 hops Only other routers inspect routing packet Slow convergence of network changes Authentication between neighbors RIP packets sent out via multicast so only routers or other network devices need to inspect packet. Security is added to prevent malicious attacks on the routing table. (c) ITT Educational Services, Inc.

EIGRP Only routing changes are sent 9/17/2018 EIGRP Only routing changes are sent Hello packets sent based on speed of network Limited to 255 hops Changes are sent as soon as detected Hops calculated on distance and bandwidth Authentication between neighbors Hello packets are sent every 5 seconds on a high speed (LAN) connection and every 60 seconds on a low speed (WAN) connection. Hops are calculated using distance and connection type. Changes to routing table are sent to neighbors when detected rather than at preset intervals. (c) ITT Educational Services, Inc.

9/17/2018 EXPLORE: CONTEXTS (c) ITT Educational Services, Inc.

Designing a distance vector routing network 9/17/2018 Designing a distance vector routing network When designing their networks, students should consider the different abilities of each of the different protocols as well as the different needs of a hub and spoke network compared to a mesh network. A hub and spoke network has only one connection to each of the spokes. There isn’t a different route that could be taken that may use more hops but uses a faster connection. A full mesh network gives every router a direct connection to every other router. If a connection to a router is severed, the router may still be accessible through one of the other connections. All connections may not be rated equally. A router may have a combination of different connection types with varying speeds. The routing protocol used should consider the speed and reliability of a network connection when choosing the best route to reach a network. (c) ITT Educational Services, Inc.

Summary In this presentation, the following were covered: 9/17/2018 Summary In this presentation, the following were covered: Classful IP routing Distance vector routing protocols RIP, RIPv2, and EIGRP Distance vector IP routed network design (c) ITT Educational Services, Inc.

Unit 8: Assignments Assignment 8.3 Solving a Business Challenge Using Distance Vector IP Routing.