Controller-Based Wireless LAN Fundamentals: An end-to-end reference guide to design, deploy, manage, and secure 802.11 wireless networks

• Copyright 2011
• Dimensions: 7-3/8" x 9-1/8"
• Pages: 320
• Edition: 1st

• eBook
• ISBN-10: 0-13-290384-9
• ISBN-13: 978-0-13-290384-4

Controller-Based Wireless LAN Fundamentals

An end-to-end reference guide to design, deploy, manage, and secure 802.11 wireless networks

Jeff Smith
Jake Woodhams
Robert Marg

As wired networks are increasingly replaced with 802.11n wireless connections, enterprise users are shifting to centralized, next-generation architectures built around Wireless LAN Controllers (WLC). These networks will increasingly run business-critical voice, data, and video applications that once required wired Ethernet.

In Controller-Based Wireless LAN Fundamentals, three senior Cisco wireless experts bring together all the practical and conceptual knowledge professionals need to confidently design, configure, deploy, manage, and troubleshoot 802.11n networks with Cisco Unified Wireless Network (CUWN) technologies.

The authors first introduce the core principles, components, and advantages of next-generation wireless networks built with Cisco offerings. Drawing on their pioneering experience, the authors present tips, insights, and best practices for network design and implementation as well as detailed configuration examples.

Next, they illuminate key technologies ranging from WLCs to Lightweight Access Point Protocol (LWAPP) and Control and Provisioning of Wireless Access Points (CAPWAP), Fixed Mobile Convergence to WiFi Voice. They also show how to take advantage of the CUWN’s end-to-end security, automatic configuration, self-healing, and integrated management capabilities.

This book serves as a practical, hands-on reference for all network administrators, designers, and engineers through the entire project lifecycle, and an authoritative learning tool for new wireless certification programs. This is the only book that

• Fully covers the principles and components of next-generation wireless networks built with Cisco WLCs and Cisco 802.11n AP
• Brings together real-world tips, insights, and best practices for designing and implementing next-generation wireless networks
• Presents start-to-finish configuration examples for common deployment scenarios
• Reflects the extensive first-hand experience of Cisco experts

• Gain an operational and design-level understanding of WLAN Controller (WLC) architectures, related technologies, and the problems they solve
• Understand 802.11n, MIMO, and protocols developed to support WLC architecture
• Use Cisco technologies to enhance wireless network reliability, resilience, and scalability while reducing operating expenses
• Safeguard your assets using Cisco Unified Wireless Network’s advanced security features
• Design wireless networks capable of serving as an enterprise’s primary or only access network and supporting advanced mobility services
• Utilize Cisco Wireless Control System (WCS) to plan, deploy, monitor, troubleshoot, and report on wireless networks throughout their lifecycles
• Configure Cisco wireless LANs for multicasting
• Quickly troubleshoot problems with Cisco controller-based wireless LANs

This book is part of the Cisco Press® Fundamentals Series. Books in this series introduce networking professionals to new networking technologies, covering network topologies, sample deployment concepts, protocols, and management techniques.

Category: Wireless

Covers: Cisco Controller-Based Wireless LANs

Table of Contents

Introduction

Chapter 1 The Need for Controller-Based Wireless Networks

Why Wireless LAN Controllers Were Created

Why You Need to Use a Wireless LAN Controller

Controller-Based WLAN Functional and Elemental Architecture

Autonomous AP Issues and the WLC Remedy

    Problem: WLAN APs Are Difficult to Deploy

    Problem: WLANs Are Not Secure

    Problem: Infrastructure Device Configuration and Scaling

        Problem: Autonomous AP Costs for Configuring Each AP

        Problem: Autonomous AP Costs for Keeping Each AP’s Software Up to Date

        Problem: RF Expertise and Configuration Challenges

Mobility Applications Enabled by Controller-Based WLANs

WLANs Do Not Provide the Performance and Robustness Needed for Use as a Primary Access Network

Summary

Chapter 2 Wireless LAN Protocols

Understanding the Relevant Standards

    Wi-Fi Alliance

    Cisco Compatible Extensions

    IETF

The Physical Layer

    Physical Layer Concepts

CAPWAP

    CAPWAP Versus LWAPP

    CAPWAP Protocol Fundamentals

        CAPWAP Terminology

        CAPWAP Control Messages

        CAPWAP Data Messages

        CAPWAP State Machine

        CUWN Implementation of the CAPWAP Discovery

        CAPWAP Transport

    CAPWAP MAC Modes

        Split MAC Mode

        Local MAC Mode

    Summary of CAPWAP

Packet Flow in the Cisco Unified Wireless Network

    CAPWAP Control

    CAPWAP Data Path: Centrally Bridged Traffic

    CAPWAP Data Path: Locally Bridged Traffic

Summary of Packet Flow

Summary

References

Chapter 3 802.11n

IEEE 802.11n Standard

    802.11n MAC

    Other 802.11 Standards Used with 802.11n

    Frequency Bands Supported by 802.11n

Antenna Arrays

    Transmit Beam Forming (TxBF)

    Beam Steering

    Spatial Multiplexing

    Transmit Diversity

Multiple Input, Multiple Output (MIMO)

    Multipath

    MIMO Nomenclature

    Receiver Diversity

        Branch Selection Diversity

        Branch-Combining Diversity

        Diversity Antenna Array, Type, Orientation, and Spacing

    Transmit Beam-Forming Types

        Legacy Beam Forming

        Implicit Beam Forming

        Explicit Beam Forming

    MIMO Antenna Array Coverage and Placement

Coding

    Binary Convolutional Coding (BCC)

    Low-Density Parity Checking (LDPC)

HT PHY and Operation

    HT Mixed

    HT-Greenfield Format

Channel Bonding/40-MHz-Wide Channels

    Protection

Power Management

Packet Aggregation

    Bursting/Block ACK (BACK)

    Short Guard Interval (GI)

    Reduced Inter-Frame Spacing (RIFS)

Reverse Direction Protocol (RDP)

Modulation and Coding Schemes (MCS)

Configuration Requirements to Obtain HT Rates

Predicting 802.11 Link Performance

Summary

Chapter 4 Cisco Unified Wireless LAN Security Fundamentals

Understanding WLAN Security Challenges

    Vulnerabilities Inherent to the Radio Transmission Medium

        Physical Containment Problem

        Unlicensed Radio Spectrum Problem

    Vulnerabilities Inherent to the Standards Definitions

        Authentication and Encryption Weaknesses

        Unauthenticated Management Frames

    Vulnerabilities Inherent to Mobility

    Misconfigured Wireless Devices and Clients

    Rogue Access Points and Devices

    Readily Available Profiling and Attack Tools

Addressing the WLAN Security Challenges

    Background on Strong Authentication and Privacy

        How WEP Encryption Works

        How WEP Is Broken

        802.11 Authentication

    Addressing the Strong Authentication and Privacy Challenges

        Authentication Framework

        Authentication Algorithm

        Data Privacy and Integrity

        Alternative Approaches to Authentication and Data Privacy

    Rogue Access Point Detection and Wireless Intrusion Prevention

    Secure Management and Security Policies

Summary

References

Chapter 5 Design Considerations

100 Percent Wireless Access Layer

    Client Device Power

    RF Vulnerability

    Volume of Network Traffic

Increased and Difficult WLAN Coverage Requirements

    Elevators

        External Bleed-Through

        Elevator Shaft Coverage

        Access Point Installed in Elevator Car

Continuous Availability and Outage Planning

    Power Loss

        Equipment Failures: APs, WLCs, and Backhaul Network

    RF Interference

        Denial of Service Attacks

        Business Operation Continuity in the WLAN Era

Power Conservation

Flexibility

WLAN Capacity

Summary

Chapter 6 Cisco Unified Wireless LAN Architectures

Cisco Unified Wireless LAN Architecture Review

Architectural Flexibility, Scalability, and Resiliency

    Architectural Flexibility

    Architectural Resiliency

        N:1 WLC Redundancy

        N:N WLC Redundancy

        N:N:1 WLC Redundancy

    Architectural Scalability

        Mobility

        Mobility Domains

Campus Architectures

    Enterprise Wiring Closet Deployment

    Enterprise Distribution Layer Deployment

    Data Center or Services Block Deployments

    Campus HREAP

Branch Architectures

    Distributed Branch Controller Placement

    Centralized Controller Placement with HREAP

    Office Extend AP (OEAP)

Summary

Chapter 7 Troubleshooting

Tools for Troubleshooting 802.11 Wireless Networks

    Wireless LAN Controller Command-Line Interface

    Wireless Control System (WCS)

    Wireless Protocol Analyzer

    Spectrum Analyzers

Isolating Issues on the Cisco Unified Wireless Network

    Protocol/Network Issues

        LWAPP/CAPWAP Discovery Process

        Troubleshooting the LWAPP CAPWAP Discovery Process

        Network Considerations

    Client Troubleshooting

        Troubleshooting Client Issues Using the WLC CLI

        Troubleshooting Client Issues Using WCS

        Common Client Problems and Solutions

The Wireless Medium: Troubleshooting Performance-Related Issues

    Coverage and Interference Issues

        Detecting, Isolating, and Solving Coverage Issues

        Detecting, Isolating, and Solving Interference Issues

Troubleshooting Advanced Wireless LAN Services

    Voice over WLAN

        Voice over WLAN Challenges

        Troubleshooting VoWLAN

    Location Troubleshooting

        Troubleshooting Location Accuracy

Summary

Chapter 8 Introduction to WCS

Designing Wireless Networks with WCS

    WCS Requirements

    WCS Interface

    WCS Monitoring

        Maps

        Controllers and AP Monitor

        Client Monitoring

    WCS Reporting

    WCS Configuration

        Controller Configuration Templates

        WCS Configuration and Template Auditing

        AP Configuration Templates

    WCS Services

    WCS Administration

        Role-Based Access Control (RBAC)

        WCS Virtual Domains

        WCS License Center

Additional Benefits of WCS: Planning and Calibration Tools

    WCS Planning

    WCS Calibration

Summary

Chapter 9 Next-Generation Advanced Topics: Multicast

Multicast

    Multicast Definition

    Multicast Addressing

    Multicast Forwarding

        Multicast Distribution Trees

        Protocol Independent Multicasting (PIM)

        IGMP

Multicast Configuration in the CUWN

    Access Point–to–Client Delivery

    Client–to–Access Point Delivery

    Enabling Multicast on a Cisco WLAN Controller

        MGIDs

    Multicast Mobility Messaging

    Enabling Multicast on a Cisco Router or Layer 3 Switch

VideoStream

    Principles of VideoStream

        Multicast Reliability

        QoS

    Configuring VideoStream on the WLC

Additional Design Recommendations

    Wireless Multicast Roaming

    Wireless CAPWAP Fragmentation

    All WLCs Have the Same CAPWAP Multicast Group Address

    WLC Placement

Summary

9781587058257    TOC    10/11/2010

Submit Errata