自顶向下网络设计

Contents

Introduction　xxii

Part I　Identifying Your Customer's Needs and Goals

Chapter 1　Analyzing Business Goals and Constraints

Using a Top-Down Network Design Methodology

Using a Structured Network Design Process

Systems Development Life Cycles

Plan Design Implement Operate Optimize （PDIOO） Network Life Cycle

Analyzing Business Goals

Working with Your Client

Changes in Enterprise Networks

Networks Must Make Business Sense

Networks Offer a Service

The Need to Support Mobile Users

The Importance of Network Security and Resiliency

Typical Network Design Business Goals

Identifying the Scope 网络设计f a Network Design Project

Identifying a Customer's Network Applications

Analyzing Business Constraints

Politics and Policies

Budgetary and Staffing Constraints

Project Scheduling

Business Goals Checklist

Summary

Review Questions

Design Scenario

Chapter 2　Analyzing Technical Goals and Tradeoffs

Scalability

Planning for Expansion

Expanding Access to Data

Constraints on Scalability

Availability

Disaster Recovery

Specifying Availability Requirements

Five Nines Availability

The Cost of Downtime

Mean Time Between Failure and Mean Time to Repair

Network Performance

Network Performance Definitions

Optimum Network Utilization

Throughput

Throughput of Internetworking Devices

Application Layer Throughput

Accuracy

Efficiency

Delay and Delay Variation

Causes of Delay

Delay Variation

Response Time

Security

Identifying Network Assets

Analyzing Security Risks

Reconnaissance Attacks

Denial-of-Service Attacks

Developing Security Requirements

Manageability

Usability

Adaptability

Affordability

Making Network Design Tradeoffs

Technical Goals Checklist

Summary

Review Questions

Design Scenario

Chapter 3　Characterizing the Existing Internetwork

Characterizing the Network Infrastructure

Developing a Network Map

Characterizing Large Internetworks

Characterizing the Logical Architecture

Developing a Modular Block Diagram

Characterizing Network Addressing and Naming

Characterizing Wiring and Media

Checking Architectural and Environmental Constraints

Checking a Site for a Wireless Installation

Performing a Wireless Site Survey

Checking the Health of the Existing Internetwork

Developing a Baseline of Network Performance

Analyzing Network Availability

Analyzing Network Utilization

Measuring Bandwidth Utilization by Protocol

Analyzing Network Accuracy

Analyzing Errors on Switched Ethernet Networks

Analyzing Network Efficiency

Analyzing Delay and Response Time

Checking the Status of Major Routers， Switches， and Firewalls

Network Health Checklist

Summary

Review Questions

Hands-On Project

Design Scenario

Chapter 4　Characterizing Network Traffic

Characterizing Traffic Flow

Identifying Major Traffic Sources and Stores

Documenting Traffic Flow on the Existing Network

Characterizing Types of Traffic Flow for New Network Applications

Terminal/Host Traffic Flow

Client/Server Traffic Flow

Peer-to-Peer Traffic Flow

Server/Server Traffic Flow

Distributed Computing Traffic Flow

Traffic Flow in Voice over IP Networks

Documenting Traffic Flow for New and Existing Network Applications

Characterizing Traffic Load

Calculating Theoretical Traffic Load

Documenting Application-Usage Patterns

Refining Estimates of Traffic Load Caused by Applications

Estimating Traffic Load Caused by Routing Protocols

Characterizing Traffic Behavior

Broadcast/Multicast Behavior

Network Efficiency

Frame Size

Windowing and Flow Control

Error-Recovery Mechanisms

Characterizing Quality of Service Requirements

ATM QoS Specifications

Constant Bit Rate Service Category

Real-time Variable Bit Rate Service Category

Non-real-time Variable Bit Rate Service Category

Unspecified Bit Rate Service Category

Available Bit Rate Service Category

Guaranteed Frame Rate Service Category

IETF Integrated Services Working Group QoS Specifications

Controlled-Load Service

Guaranteed Service

IETF Differentiated Services Working Group QoS Specifications

Grade of Service Requirements for Voice Applications

Documenting QoS Requirements

Network Traffic Checklist

Summary

Review Questions

Design Scenario

Summary for Part I

Part II　Logical Network Design

Chapter 5　Designing a Network Topology

Hierarchical Network Design

Why Use a Hierarchical Network Design Model？

Flat Versus Hierarchical Topologies

Flat WAN Topologies

Flat LAN Topologies

Mesh Versus Hierarchical-Mesh Topologies

Classic Three-Layer Hierarchical Model

Core Layer

Distribution Layer

Access Layer

Guidelines for Hierarchical Network Design

Redundant Network Design Topologies

Backup Paths

Load Sharing

Modular Network Design

Cisco SAFE Security Reference Architecture

Designing a Campus Network Design Topology

Spanning Tree Protocol

Spanning Tree Cost Values

Rapid Spanning Tree Protocol

RSTP Convergence and Reconvergence

Selecting the Root Bridge

Scaling the Spanning Tree Protocol

Virtual LANs

Fundamental VLAN Designs

Wireless LANs

Positioning an Access Point for Maximum Coverage

WLANs and VLANs

Redundant Wireless Access Points

Redundancy and Load Sharing in Wired LANs

Server Redundancy

Workstation-to-Router Redundancy

Hot Standby Router Protocol

Gateway Load Balancing Protocol

Designing the Enterprise Edge Topology

Redundant WAN Segments

Circuit Diversity

Multihoming the Internet Connection

Virtual Private Networking

Site-to-Site VPNs

Remote-Access VPNs

Service Provider Edge

Secure Network Design Topologies

Planning for Physical Security

Meeting Security Goals with Firewall Topologies

Summary

Review Questions

Design Scenario

……

Part III　Physical Network Design

Part IV　Testing， Optimizing， and Documenting Your Network Design

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