Tài liệu Cisco AVVID and IP Telephony P1 doc

Capital Network Solutions is aCisco Premier Partner, specializing in Voice Access and Wireless solutions,and has completed a number of major projects for large internationalorganizations

1 YEAR UPGRADE

B U Y E R P R O T E C T I O N P L A N

Design and Deploy IP Telephony Solutions

• Step-by-Step Instructions for Using AVVID Applications in Single Site and

Multiple Site Solutions

• Complete Coverage of Voice and Video Gatekeeper Design

• Hundreds of Configuring & Implementing and Designing & Planning

Sidebars, FAQs, and Case Studies!

Cisco AVVID

IP Telephony

®

Robert Padjen Larry Keefer Sean Thurston Jeff Bankston Michael E Flannagan Martin Walshaw Technical Editor

and

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Cisco ® AVVID and IP Telephony Design & Implementation

Copyright © 2001 by Syngress Publishing, Inc All rights reserved Printed in the United States of America Except as permitted under the Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication.

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Acknowledgments

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Contributors

Callisma and he has written a number of texts on Cisco networking Inaddition to instructing, Robert works as an expert witness in the com-puter and networking fields

Director of and Senior Network Consultant for Capital NetworkSolutions Ltd., based in South Wales, UK Capital Network Solutions is aCisco Premier Partner, specializing in Voice Access and Wireless solutions,and has completed a number of major projects for large internationalorganizations.Their Web site can be found at www.capitalnetworks.co.uk.Mark graduated from the University of Glamorgan with a BSc (Hons) inComputer Science in 1994 and has been working as a networking con-sultant ever since He now lives in Cardiff with his wife Sarah and sonCameron

Network Consulting Engineer and Team Leader in the NetworkSupported Accounts (NSA) Group at Cisco Systems Mike is a member ofthe global Quality of Service (QoS) Team and has extensive networkdesign experience, with emphasis on Routing Protocol design andQuality of Service mechanisms Mike’s experience, prior to joining CiscoSystems, includes enterprise network architecture, IT management, andconsulting Mike’s QoS testing and research was used to recommend theimplementation of various QoS mechanisms for one of the world’s largestpharmaceutical companies, and he has participated in large-scale QoSdesigns for several major US companies In addition to holding variouscertifications from Cisco, 3Com, and Nortel Networks, Mike has passedboth the CCIE Routing/Switching and the CCIE Design written examsand is currently preparing for his CCIE Lab exams He lives in

Morrisville, NC

Callisma in Wakefield, MA He has over 14 years of experience in the datanetworking industry, the last four as a consultant He specializes in thedesign and implementation of complex networks in the financial, medical,manufacturing, and service provider industries His expertise includesrouting, switching, and security equipment from Cisco Systems andNortel Networks Rob holds a Bachelor of Science degree from theUniversity of New Hampshire

Network Architect at BCI Associates He has designed, developed, andimplemented networks ranging from 75 users to enterprises in excess of47,000 users spanning 40 buildings in a campus,WAN, and metropolitannetworks He has troubleshot the same size networks, configured andmodified LAN equipment from Cisco, 3Com, Cabletron, Bay Networks,and many smaller vendors He serves as the assistant to the BranchTechnical Manager for new business development with ATM,Voice over

IP, enterprise LAN/WAN development, and other such technologies Jeffhas published three books on networking, published numerous technicalwhitepapers and articles, and continues to write for four major technicaljournals He enjoys technical testing and evaluation of vendor products inhis off time, which helps him to recommend proper technologies for e-commerce environments He enjoys teaching networking classes forElement K online distance learning (www.elementk.com) where he alsodevelops new courses for the system Jeff holds five major industry certifi-cations including Cisco CCDP, CCNP Voice Specialist, and the CCNPSecurity Specialist He is a Cisco CCIE candidate focusing on wirelessnetworking

MCSE, MCP+I, Master CAN, HP Start) is a Consultant with Callisma.His areas of specialization include design, integration, implementation, anddocumentation of multiple protocol and layer networks with voice, video,and data He recently designed and implemented a multisite AVVID net-work utilizing CallManager 3.0x IP-PBX, IP phones, inline powerswitches, voice analog, and digital gateways Prior to Callisma, Larry was a

Senior Network Engineer and Team Leader at Rush Creek Solutions Heholds a Bachelor of Science in Business Information Systems and BusinessAdministration from Illinois State University He has completed coursework toward an M.S degree in Computer Information Systems,

University of Phoenix

Consultant with Callisma He is currently engaged in a broadband mization project for a major U.S backbone service provider He special-izes in Cisco routers, LAN switches, Cisco’s optical networking productoffering as well as Microsoft NT, and network design and implementa-tion Eric’s background includes positions as a Project Manager for amajor international law firm and as a Project Manager for Nortel

Technical Editor and Contributor

working for Cisco Systems in South Africa His areas of specialty include

IP Telephony (including all voice and video applications such as IPCC)and security, both of which keep him busy night and day During the last

14 years, Martin has dabbled in many aspects of the IT industry, rangingfrom programming in RPG III and Cobol to PC sales.When Martin isnot working, he likes to spend time with his expectant wife Val and hisson Joshua.Without their patience, understanding, support, and mostimportantly love, projects such as this would not be possible

Architect with Seimans Business Services He provides Network and DataCenter design solutions for large-scale deployment His specialties includeimplementation of multivendor routing and switching equipment andXoIP (Everything over IP) installations Sean’s background includes posi-tions as a technical analyst for Sprint-Paranet and the Director of a Brickand Mortar advertising dot-com Sean is also a contributing author to

Syngress Publishing’s Building a Cisco Network for Windows 2000 (ISBN:

1-928994-00-8) Sean lives in Renton,WA with his fiancée Kerry He iscurrently pursuing his CCIE

Technical Reviewer and

Contributor

Designing with Legacy Systems in Mind 4

Switching 9

Summary 21

Introduction 26

Linking Communications with UnifiedMessaging 28Choosing to Implement IP Telephony 28

yields service that is

available for all but

approximately eight

hours per year.

Introducing Cisco’s IP Telephony Applications 41

Internet Communications Software 43

AutoAttendant 45Third-Party IP Telephony Applications 45Interactive Intelligence’s Solutions 45Latitude Communication’s Solutions 46Intelligent Telemanagement Solutions 46

Gateways 47Gatekeepers 48

Using Routers for a Converged Network 50

Explore the Four

Primary Roles a Server

Contents xiii

Summary 60

Introduction 66

Understanding the Capabilities of Gateway

Understand the Capabilities of Gateway Protocols

Session Initiation Protocol supports five elements of establishing and

terminating communications:

Redundancy within a CallManager Cluster 106

What Are the VideoconferencingRequirements? 121Does the Customer Need Clustering? 121Does the Customer Need Multiple

Clusters? 122

Summary 125

Chapter 5 Voice and Video

Learn the Guidelines

for Multiple Clusters

There are three

multicluster designs that

may be tailored to fit your

■ Multiple clusters over a

multisite WAN with

distributed call

processing

■ Multiple clusters over a

multisite WAN with

centralized call

processing

Using Bandwidth Limits in Your Network 142Using Accounting within Your Network 143Using Multicast or Unicast Addresses

Designing a Large H.323 Network 144

Implementing Zones in Your Network 146

A Gatekeeper’s Role in Voice and VideoNetworking 152

Selecting a Router Hardware Platform 153

Redundancy 154Configuring HSRP between Gatekeepers 155Using Technology Prefixes for

Redundancy 156Using Zone Prefixes and Gatekeeper

Placing and Configuring Gatekeepers:

Design a Large H.323 Network

NOTE

As of 12.1(5)XM, the upper level, or direc- tory gate keeper could only service approxi- mately six lower level gatekeepers As this limit will likely change often, you should check with your local Cisco resource or the Cisco TAC for updated limits.

Introduction 192

Defining the Customer Contact Channels 195

Call Accounting, Billing, and Network

Call Accounting and Billing Solutions 208Designing Voice and Unified Messaging Solutions 211Understanding Other Voice Applications 214Summary 216

multiple callers into a

single multiway call.

The two types of

multiparticipant voice

calls supported by the

Cisco CallManager are

ad-hoc and meet-me

Contents xvii

Chapter 8 Advanced QoS for

Introduction 222Using the Resource Reservation Protocol 223

Reservation Styles and Merging Flows 232

Using Class-Based Weighted Fair Queuing 236

Why Do I Need CBWFQ on My Network? 238Case Study: Using a SQL Application

Case Study:Total Traffic Classification

Using Weighted Random Early Detection 247

Using Generic Traffic Shaping and Frame

Understand the Advantages and Disadvantages of Using RSVP

Advantages:

■ Admissions Control

RSVP not only provides QoS, but also helps other applications by

not transmitting when

the network is busy.

■ Network Independence/

Flexibility RSVP is not

dependent on a particular networking architecture.

■ Interoperability RSVP

works inside existing protocols and with other QoS mechanisms.

■ Distributed RSVP is a

distributed service and therefore has no central point of failure.

■ Transparency RSVP

can tunnel across an RSVP-unaware network.

Disadvantages:

■ Scaling Issues

Multifield classification and statefulness of reservations may consume memory and CPU resources.

■ Route selection and stability The shortest

path may not have available resources, and the active path may go down.

■ Setup time An

application cannot start transmitting until the reservation has been completed.