Eigrp.ppt • 1. © 2007 Cisco Systems, Inc. All rights reserved. Cisco Public 1Version 4.0 EIGRP Routing Protocols and Concepts Ed Scrimaglia - CCIE • 2© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public Objectives  Describe the background and history of Enhanced Interior Gateway Routing Protocol (EIGRP).

Dec 01, 2011  CCNP PPT Slides CCNP PPT Slides. Posted by Windows Help Desk at 1:54 AM. Email This BlogThis! Share to Twitter Share to Facebook Share to Pinterest. ROUTE 642-902 C-B-T N u g g e t s; CCNP ROUTE 642-902 Certification Guide Dec 23 (2) Dec 22 (2). Nov 28, 2014 - PowerPoint Slides for CCNP Routing and Switching ROUTE 300-101 Official Cert Guide. View larger cover. Kevin Wallace.

 Examine the basic EIGRP configuration commands and identify their purposes.  Calculate the composite metric used by EIGRP.

 Describe the concepts and operation of DUAL.  Describe the uses of additional configuration commands in EIGRP. • 3© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public Introduction • 4© 2007 Cisco Systems, Inc.

All rights reserved. Cisco Public EIGRP  Roots of EIGRP: IGRP – Developed in 1985 to overcome RIPv1’s limited hop count – Distance vector routing protocol – Metrics used by IGRP • Bandwidth (used by default) • Delay (used by default) • Reliability • Load – Discontinued support starting with IOS 12.2(13)T & 12.2(R1s4)S • 5© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  EIGRP Message Format  EIGRP Header – Data link frame header - contains source and destination MAC address – IP packet header - contains source & destination IP address – EIGRP packet header - contains AS number – Type/Length/Field - data portion of EIGRP message • 6© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  EIGRP packet header contains: – Opcode field – Autonomous System number  EIGRP Parameters contain: – Weights – Hold time • 7© 2007 Cisco Systems, Inc.

All rights reserved. Postavschik kriptografii dlya zakritogo klyucha. Cisco Public EIGRP  TLV: IP internal contains – Metric field – Subnet mask field – Destination field  TLV: IP external contains – Fields used when external routes are imported into EIGRP routing process • 8© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  Protocol Dependent Modules (PDM) – EIGRP uses PDM to route several different protocols i.e. IP, IPX & AppleTalk – PDMs are responsible for the specific routing task for each network layer protocol • 9© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  Reliable Transport Protocol (RTP)  Purpose of RTP – Used by EIGRP to transmit and receive EIGRP packets  Characteristics of RTP – Involves both reliable & unreliable delivery of EIGRP packet • Reliable delivery requires acknowledgment from destination • Unreliable delivery does not require an acknowledgement from destination – Packets can be sent • Unicast • Multicast – Using address 224.0.0.10 • 10© 2007 Cisco Systems, Inc.

All rights reserved. Cisco Public EIGRP  EIGRP’s 5 Packet Types  Hello packets – Used to discover & form adjacencies with neighbors • 11© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  Update packets – Used to propagate routing information • 12© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  Query packets – Used by DUAL for searching for networks – Can use Unicast or Multicast  Reply packets – Reply packet – Can use Unicast only  Acknowledgement packets – Used to acknowledge receipt of update, query & reply packets • 13© 2007 Cisco Systems, Inc.

All rights reserved. Cisco Public EIGRP  Purpose of Hello Protocol – To discover & establish adjacencies with neighbor routers  Characteristics of hello protocol – Time interval for sending hello packet • Most networks it is every 5 seconds • Multipoint non broadcast multi- access networks – Unicast every 60 seconds – Holdtime • This is the maximum time router should wait before declaring a neighbor down • Default holdtime – 3 times hello interval • 14© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  EIGRP Bounded Updates – EIGRP only sends update when there is a change in route status – Partial update • A partial update includes only the route information that has changed – the whole routing table is NOT sent – Bounded update • When a route changes, only those devices that are impacted will be notified of the change – EIGRP’s use of partial bounded updates minimizes use of bandwidth • 15© 2007 Cisco Systems, Inc. All rights reserved. Cisco Public EIGRP  Diffusing Update Algorithm (DUAL) – Purpose • EIGRP’s primary method for preventing routing loops – Advantage of using DUAL • Provides for fast convergence time by keeping a list of loop-free backup routes • 16© 2007 Cisco Systems, Inc. All rights reserved.