Routing Protocols and Concepts: Chapter 3 docx

Chapter 9 EIGRP 2 For further information  This presentation is an overview of what is covered in the curriculum/book.  For further explanation and details, please read the chapter/curriculum.  Book:  Routing Protocols and Concepts  By Rick Graziani and Allan Johnson  ISBN: 1-58713-206-0  ISBN-13: 978-58713- 206-3 3 Topics  Introduction to EIGRP  EIGRP: An Enhanced Distance Vector Routing Protocol  EIGRP Message Format  Protocol-Dependent Modules  RTP and EIGRP Packet Types  Hello Protocol  EIGRP Bounded Updates  DUAL: An Introduction  Administrative Distance  Authentication  Basic EIGRP Configuration  EIGRP Network Topology  Autonomous Systems and Process IDs  The router eigrp Command  The network Command  Verifying EIGRP  Examining the Routing Table  EIGRP Metric Calculation  EIGRP Composite Metric and the K Values  EIGRP Metrics  Using the bandwidth Command  Calculating the EIGRP Metric  DUAL  DUAL Concepts  Successor and Feasible Distance  Feasible Successors, Feasibility Condition, and Reported Distance  Topology Table: Successor and Feasible Successor  Topology Table: No Feasible Successor  Finite State Machine  More EIGRP Configurations  The Null0 Summary Route  Disabling Automatic Summarization  Manual Summarization  EIGRP Default Route  Fine-Tuning EIGRP Introduction to EIGRP  EIGRP: An Enhanced Distance Vector Routing Protocol  EIGRP Message Format  Protocol-Dependent Modules  RTP and EIGRP Packet Types  Hello Protocol  EIGRP Bounded Updates  DUAL: An Introduction  Administrative Distance  Authentication 5 Introduction to EIGRP  Enhanced Interior Gateway Routing Protocol (EIGRP)  Distance vector  Classless routing protocol  Released in 1992 with Cisco IOS Software Release 9.21.  Enhancement of Cisco Interior Gateway Routing Protocol (IGRP).  Both are Cisco proprietary  Operate only on Cisco routers. 6 Introduction to EIGRP  The term hybrid routing protocol is sometimes used to define EIGRP.  Misleading, not a hybrid between distance vector and link-state  Solely a distance vector routing protocol. 7 Introduction to EIGRP  Instead of hop count, both IGRP and EIGRP use metrics composed of bandwidth, delay, reliability, and load.  Only bandwidth and delay are used by default. 8 EIGRP Message Format  EIGRP Header field  Data field = Type/Length/Value, or TLV.  Encapsulated in an IP packet.  Protocol field = 88 (EIGRP)  Destination IP address = multicast 224.0.0.10.  If the EIGRP packet is encapsulated in an Ethernet frame:  Destination MAC, multicast address: 01-00-5E-00-00-0A 9 EIGRP Message Format  Opcode specifies the EIGRP packet type as one of the following:  Update  Query  Reply  Hello Note: All fields are shown to provide an accurate picture of the EIGRP message format. However, only the fields relevant to the CCNA candidate are discussed. 10 EIGRP Packet Header Message Format  Autonomous system number  Specifies the EIGRP routing process.  Unlike RIP, Cisco routers can run multiple instances of EIGRP. (more later)  EIGRP packet types are discussed later in this chapter. Note: All fields are shown to provide an accurate picture of the EIGRP message format. However, only the fields relevant to the CCNA candidate are discussed. [...]... each routing update packet that it receives However, authentication does not encrypt the router’s routing table 28 Basic EIGRP Configuration EIGRP Network Topology Autonomous Systems and Process IDs The router eigrp Command The network Command Verifying EIGRP Examining the Routing Table Topology Includes the addition of the ISP router R1 and R2 routers have subnets that are part of the 172.16.0.0/16 30 ... different protocols, including: IP, Internetwork Packet Exchange (IPX) AppleTalk, PDMs are responsible for the specific routing tasks for each network layer protocol Example The IP-EIGRP module is responsible for: Sending and receiving EIGRP packets that are encapsulated in IP Using DUAL to build and maintain the IP routing table 15 RTP and EIGRP Packet Types Reliable Transport Protocol (RTP) Delivery and. .. composite metric Default, only bandwidth (K1) and delay (K3) are weighted (used) Set to 1 Other K values are set to 0 (affect load and reliability) More later The hold time Amount of time the EIGRP neighbor receiving this message should wait before considering the advertising router to be down More later 11 IP Internal Routes TLV Metric fields: Delay and Bandwidth Reliability and Load (more later) Subnet... configurations The connection between R2 and ISP is represented with a loopback interface on Router R2 32 R3’s running-config hostname R3 ! interface FastEthernet0/0 ip address 192.168.1.1 255.255.255.0 ! interface Serial0/0/0 ip address 192.168.10.6 255.255.255.252 clockrate 64000 ! interface Serial0/0/1 ip address 192.168.10.10 255.255.255.252 33 Autonomous Systems and Process IDs An autonomous system... convergence algorithm used by EIGRP First proposed by E W Dijkstra and C S Scholten The most prominent work with DUAL has been done by J J Garcia-LunaAceves Routing loops, even temporary ones, can be extremely detrimental to network performance Distance vector routing protocols such as RIP prevent routing loops with hold-down timers and split horizon Although EIGRP uses both of these techniques, it... interior gateway protocols (IGP), EIGRP is the most preferred by the Cisco IOS software because it has the lowest AD Later in this chapter, you learn how to configure EIGRP summary routes 27 Authentication Like other routing protocols, EIGRP can be configured for authentication It is good practice to authenticate transmitted routing information This practice ensures that routers will accept routing information... presents a common routing policy to the Internet Described in RFC 1 930 AS numbers are assigned by IANA and its RIR Same authority that assigns IP address space 34 Autonomous Systems and Process IDs Who needs an autonomous system number? ISPs Internet backbone providers Large institutions connecting to other entities that also have an autonomous system number Uses exterior gateway routing protocol BGP... of companies and institutions with IP networks do not need an autonomous system number because they come under the control of a larger entity such as an ISP BGP 35 Process ID Router(config)# router eigrp autonomous-system Router(config)# router eigrp 1 Must be same on all routers in EIGRP routing domain Both EIGRP and OSPF use a process ID to represent an instance of their respective routing protocol... known as a feasible successor (more later.) So, R2 sends an EIGRP query to its neighbors asking them whether they have a route to this downed network 4 R1 and R3 return an EIGRP acknowledgment indicating that they have received the query from R2 5 R1 and R3 send an EIGRP reply message in response to the query sent by R2 In this case, the reply would state that the router does not have a route to this network... TLV In this chapter, we import or redistribute a default static route into EIGRP Additional fields All the fields used by the IP Internal TLV 13 Note on MTU Some EIGRP literature might incorrectly state that the maximum transmission unit (MTU) is one of the metrics used by EIGRP MTU is not a metric used by EIGRP The MTU is included in the routing updates, but it is not used to determine the routing metric . chapter/ curriculum.  Book:  Routing Protocols and Concepts  By Rick Graziani and Allan Johnson  ISBN: 1-587 13- 206-0  ISBN- 13: 978-587 13- 206 -3 3 Topics . Topology  Autonomous Systems and Process IDs  The router eigrp Command  The network Command  Verifying EIGRP  Examining the Routing Table  EIGRP Metric