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Configuring IS-IS Protocol BSCI Configuring IS-IS Protocol Version 1.2 – Module 7 Student Guide Copyright 2002, Cisco Systems, Inc. All rights reserved. Cisco Systems has more than 200 offices in the following countries and regions. Addresses, phone numbers, and fax numbers are listed on the Cisco Web site at www.cisco.com/go/offices. Argentina • Australia • Austria • Belgium • Brazil • Bulgaria • Canada • Chile • China PRC • Colombia • Costa Rica Croatia • Czech Republic • Denmark • Dubai, UAE • Finland • France • Germany • Greece • Hong Kong SAR • Hungary India • Indonesia • Ireland • Israel • Italy • Japan • Korea • Luxembourg • Malaysia • Mexico • The Netherlands New Zealand • Norway • Peru • Philippines • Poland • Portugal • Puerto Rico • Romania • Russia • Saudi Arabia Scotland • Singapore • Slovakia • Slovenia • South Africa • Spain • Sweden • Switzerland • Taiwan • Thailand • Turkey Ukraine • United Kingdom • United States • Venezuela • Vietnam • Zimbabwe Copyright 2002, Cisco Systems, Inc. All rights reserved. CCIP, the Cisco Powered Network mark, the Cisco Systems Verified logo, Cisco Unity, Follow Me Browsing, FormShare, Internet Quotient, iQ Breakthrough, iQ Expertise, iQ FastTrack, the iQ logo, iQ Net Readiness Scorecard, Networking Academy, ScriptShare, SMARTnet, TransPath, and Voice LAN are trademarks of Cisco Systems, Inc.; Changing the Way We Work, Live, Play, and Learn, Discover All That’s Possible, The Fastest Way to Increase Your Internet Quotient, and iQuick Study are service marks of Cisco Systems, Inc.; and Aironet, ASIST, BPX, Catalyst, CCDA, CCDP, CCIE, CCNA, CCNP, Cisco, the Cisco Certified Internetwork Expert logo, Cisco IOS, the Cisco IOS logo, Cisco Press, Cisco Systems, Cisco Systems Capital, the Cisco Systems logo, Empowering the Internet Generation, Enterprise/Solver, EtherChannel, EtherSwitch, Fast Step, GigaStack, IOS, IP/TV, LightStream, MGX, MICA, the Networkers logo, Network Registrar, Packet, PIX, Post-Routing, Pre-Routing, RateMUX, Registrar, SlideCast, StrataView Plus, Stratm, SwitchProbe, TeleRouter, and VCO are registered trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and certain other countries. All other trademarks mentioned in this document or Web site are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (0203R) Printed in the USA 2 Building Scalable Cisco Internetworks (BSCI) v1.2 Copyright 2002, Cisco Systems, Inc. Configuring IS-IS Protocol Overview This lesson provides an overview of Intermediate System-to-Intermediate System (IS-IS) technology, and its structures and protocols, as well as basic configuration examples. The lesson begins with Open System Interconnection (OSI) routing and then focuses on Integrated IS-IS as a version that supports IP networks. Basic IS-IS and Integrated IS-IS router configuration commands, examples, and some troubleshooting guidelines are presented at the end of the lesson. The major part of this lesson is dedicated to an explanation of IS-IS concepts and capabilities, including hierarchy and addressing of OSI-based networks. Outline The lesson includes these sections: Objectives Introduction to OSI Protocols and IS-IS Routing Operation of IS-IS IP and OSI Routing with Integrated IS-IS Basic Integrated IS-IS Router Configuration Modeling WAN Networks in Integrated IS-IS Summary Review Questions Copyright 2002, Cisco Systems, Inc. Configuring IS-IS Protocol 3 Objectives This section lists the lesson objectives. Objectives Upon completing this lesson, you will be able to: • Explain basic OSI terminology and network layer protocols used in OSI • Identify similarities and differences between Integrated IS-IS and OSPF • Identify characteristics of an effective addressing plan for IS-IS deployment • Explain how networks and interfaces are represented in IS-IS • List the types of IS-IS routers and their role in IS-IS area design • Describe the hierarchical structure of IS-IS areas © 2002, Cisco Systems, Inc. All rights reserved. BSCI v1.2—7-3 Explain basic OSI terminology and network layer protocols used in OSI Identify similarities and differences between Integrated IS-IS and OSPF Identify characteristics of an effective addressing plan for IS-IS deployment Explain how networks and interfaces are represented in IS-IS List the types of IS-IS routers and their role in IS-IS area design Describe the hierarchical structure of IS-IS areas 4 Building Scalable Cisco Internetworks (BSCI) v1.2 Copyright 2002, Cisco Systems, Inc. Objectives (cont.) Objectives (cont.) • Describe the concept of establishing adjacencies • Describe the concepts of routing traffic transport and database synchronization • Explain the basic principles of area routing • Explain IS-IS NBMA (non-broadcast multi-access network) modeling solutions in switched WAN networks • Given an addressing scheme and other laboratory parameters, identify the steps to configure Cisco routers for proper Integrated IS-IS operation • Identify verification methods which ensure proper operation of Integrated IS-IS on Cisco routers © 2002, Cisco Systems, Inc. All rights reserved. BSCI v1.2—7-4 Describe the concept of establishing adjacencies Describe the concepts of routing traffic transport and database synchronization Explain the basic principles of area routing Explain IS-IS nonbroadcast multiaccess (NBMA) network modeling solutions in switched WAN networks Identify the steps to configure Cisco routers for proper Integrated IS-IS operation, given an addressing scheme and other laboratory parameters Identify verification methods that ensure proper operation of Integrated IS-IS on Cisco routers Copyright 2002, Cisco Systems, Inc. Configuring IS-IS Protocol 5 Introduction to OSI Protocols and IS-IS Routing OSI Protocols ISO and OSI? • The International Organization for Standardization (ISO) has been constituted to develop standards for data networking. • The Open System Interconnection (OSI) protocols represent an international standardization program that facilitates multivendor equipment interoperability. © 2002, Cisco Systems, Inc. All rights reserved. BSCI v1.2—7-6 The OSI protocols are part of an international program to develop data-networking protocols and other standards that facilitate multivendor equipment interoperability. The OSI program grew out of a need for international networking standards and is designed to facilitate communication between hardware and software systems despite differences in underlying architectures. The OSI specifications were conceived and implemented by two international standards organizations: the International Organization for Standardization (ISO) and the International Telecommunication Union Telecommunication Standardization Sector (ITU-T). The world of OSI internetworking includes various network services with these characteristics: Independence of underlying communications infrastructure End-to-end transfer Transparency Quality of service (QoS) selection Addressing 6 Building Scalable Cisco Internetworks (BSCI) v1.2 Copyright 2002, Cisco Systems, Inc. OSI Protocols (cont.) The OSI protocol suite supports: • Numerous standard protocols at each layer of the OSI reference model • OSI network-layer hierarchical addressing • Two routing protocols at the network layer © 2002, Cisco Systems, Inc. All rights reserved. BSCI v1.2—7-7 The OSI protocol suite supports numerous standard protocols at the physical, data-link, network, transport session, presentation, and application layers. OSI network-layer addressing is implemented by using two types of hierarchical addresses: network service access point (NSAP) addresses and network-entity titles. An NSAP is a conceptual point on the boundary between the network and the transport layers. The NSAP is the location at which OSI network services are provided to the transport layer. Each transport- layer entity is assigned a single NSAP, which is individually addressed in an OSI internetwork using NSAP addresses. The OSI protocol suite specifies two routing protocols at the network layer: End System-to- Intermediate System (ES-IS) and Intermediate System-to-Intermediate System (IS-IS). In addition, the OSI suite implements two types of network services: connectionless service and connection-oriented service. Copyright 2002, Cisco Systems, Inc. Configuring IS-IS Protocol 7 OSI Protocols—Terminology Terminology used in OSI • End system (ES) is any nonrouting network nodes (host) • Intermediate system (IS) is a router • An area is a logical entity – Formed by a set of contiguous routers, hosts, and the data links that connect them • Domain is a collection of connected areas © 2002, Cisco Systems, Inc. All rights reserved. BSCI v1.2—7-8 In an OSI network four significant architectural entities exist: hosts, areas, a backbone, and a domain. A domain is any portion of an OSI network that is under a common administrative authority. Within any OSI domain, one or more areas can be defined. An area is a logical entity; it is formed by a set of contiguous routers and the data links that connect them. All routers in the same area exchange information about all the hosts that they can reach. The areas are connected to form a backbone. All routers on the backbone know how to reach all areas. The term “end system” (ES) refers to any nonrouting host or node; “intermediate system” (IS) refers to a router. These terms are the basis for the OSI ES-IS and IS-IS protocols. 8 Building Scalable Cisco Internetworks (BSCI) v1.2
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