You are previewing Designing Large Scale Lans.
O'Reilly logo
Designing Large Scale Lans

Book Description

This unique book offers a vendor-neutral approach for designing large local area networks according to business or organizational needs, rather than from a product perspective. Author and independent network design consultant Kevin Dooley outlines "top-down network design" for building a technological infrastructure to fit your organization's requirements, a process far more effective and cost-efficient than fitting the organization to the parameters of a shrink-wrapped proprietary solution. Dooley argues that the design of a network is largely independent of the products used. Whether you use a Cisco or Juniper router, the same security issues and protocols apply. The questions he addresses in this book are need-specific: Do I use a router or a switch? Should I route between switched areas or switch between routed areas? Designing Large-Scale LANs covers everything from security, bandwidth and scalability to network reliability, which includes backup, redundancy, and points of failure. Specific technologies are analyzed in detail: network topologies, routing and switching strategies, wireless, virtual LANs, firewalls and gateways, security, Internet protocols, bandwidth, and multicast services. The book also discusses proprietary technologies that are ubiquitous, such as Cisco's IOS and Novell's IPX. This complete guide to top-down network design will help you choose the right network solutions. If you're designing large scale networks and need expert advice and guidance, look no further than Designing Large-Scale LANs.

Table of Contents

  1. Designing Large-Scale LANs
  2. Preface
    1. Audience
    2. Organization
    3. Conventions Used in This Book
    4. Comments and Questions
    5. Acknowledgments
  3. 1. Networking Objectives
    1. 1.1. Business Requirements
      1. 1.1.1. Money
      2. 1.1.2. Geography
      3. 1.1.3. Installed Base
      4. 1.1.4. Bandwidth
      5. 1.1.5. Security
      6. 1.1.6. Philosophical and Policy Requirements
    2. 1.2. OSI Protocol Stack Model
      1. 1.2.1. The Seven Layers
        1. 1.2.1.1. Layer 1
        2. 1.2.1.2. Layer 2
        3. 1.2.1.3. Layer 3
        4. 1.2.1.4. Layer 4
        5. 1.2.1.5. Layer 5
        6. 1.2.1.6. Layer 6
        7. 1.2.1.7. Layer 7
      2. 1.2.2. Where the OSI Model Breaks Down
    3. 1.3. Routing Versus Bridging
    4. 1.4. Top-Down Design Philosophy
  4. 2. Elements of Reliability
    1. 2.1. Defining Reliability
      1. 2.1.1. Failure Is a Reliability Issue
      2. 2.1.2. Performance Is a Reliability Issue
    2. 2.2. Redundancy
      1. 2.2.1. Guidelines for Implementing Redundancy
      2. 2.2.2. Redundancy by Protocol Layer
      3. 2.2.3. Multiple Simultaneous Failures
      4. 2.2.4. Complexity and Manageability
      5. 2.2.5. Automated Fault Recovery
        1. 2.2.5.1. Always let network equipment perform network functions
        2. 2.2.5.2. Intrinsic versus external automation
        3. 2.2.5.3. Examples of automated fault recovery
        4. 2.2.5.4. Fault tolerance through load balancing
        5. 2.2.5.5. Avoid manual fault-recovery systems
      6. 2.2.6. Isolating Single Points of Failure
      7. 2.2.7. Predicting Your Most Common Failures
        1. 2.2.7.1. Mean time between failures
        2. 2.2.7.2. Multiple simultaneous failures
        3. 2.2.7.3. Combining MTBF values
    3. 2.3. Failure Modes
      1. 2.3.1. Congestion
      2. 2.3.2. Traffic Anomalies
      3. 2.3.3. Software Problems
      4. 2.3.4. Human Error
  5. 3. Design Types
    1. 3.1. Basic Topologies
      1. 3.1.1. Basic Concepts
        1. 3.1.1.1. Bus topology
        2. 3.1.1.2. Ring topology
        3. 3.1.1.3. Star topology
        4. 3.1.1.4. Mesh Topology
      2. 3.1.2. Scalability
    2. 3.2. Reliability Mechanisms
      1. 3.2.1. Spanning Tree
        1. 3.2.1.1. Spanning Tree eliminates loops
        2. 3.2.1.2. Spanning Tree activates backup links and devices
      2. 3.2.2. Layer 3 Recovery Mechanisms
    3. 3.3. VLANs
      1. 3.3.1. Avoid Spaghetti VLANs
      2. 3.3.2. Protocol-Based VLAN Systems
    4. 3.4. Toward Larger Topologies
      1. 3.4.1. Collapsed Backbone
        1. 3.4.1.1. Why collapse a backbone?
        2. 3.4.1.2. Backbone capacity
        3. 3.4.1.3. Backbone redundancy
      2. 3.4.2. Distributed Backbone
        1. 3.4.2.1. Trunk capacity
        2. 3.4.2.2. Trunk fault tolerance
      3. 3.4.3. Switching Versus Routing
        1. 3.4.3.1. Ancient history
        2. 3.4.3.2. Modernizing the old rule
    5. 3.5. Hierarchical Design
      1. 3.5.1. Routing Strategies
        1. 3.5.1.1. One-armed routers and Layer 3 switches
        2. 3.5.1.2. Redundancy
          1. 3.5.1.2.1. Router-to-router segments
          2. 3.5.1.2.2. Physical diversity
        3. 3.5.1.3. Filtering
          1. 3.5.1.3.1. Filtering for security
          2. 3.5.1.3.2. Filtering for application control
          3. 3.5.1.3.3. Policy-based routing
      2. 3.5.2. Switching and Bridging Strategies
        1. 3.5.2.1. Containing broadcasts
        2. 3.5.2.2. Redundancy in bridged networks
        3. 3.5.2.3. Filtering
      3. 3.5.3. VLAN-Based Topologies
        1. 3.5.3.1. Trunk design
        2. 3.5.3.2. Trunking through a router
        3. 3.5.3.3. Trunks
          1. 3.5.3.3.1. Trunk protocols
          2. 3.5.3.3.2. Trunk redundancy
          3. 3.5.3.3.3. Trunks on servers
        4. 3.5.3.4. VLAN Distribution Areas
        5. 3.5.3.5. Sizing VLAN Distribution Areas
    6. 3.6. Implementing Reliability
      1. 3.6.1. Multiple Connections
    7. 3.7. Large-Scale LAN Topologies
      1. 3.7.1. Routers in the Core Level
      2. 3.7.2. Routers in the Distribution Level
      3. 3.7.3. Routers in Both the Core and Distribution Levels
      4. 3.7.4. Connecting Remote Sites
      5. 3.7.5. General Comments on Large-Scale Topology
  6. 4. Local Area Network Technologies
    1. 4.1. Selecting Appropriate LAN Technology
      1. 4.1.1. Cost Efficiency
      2. 4.1.2. Installed Base
      3. 4.1.3. Maintainability
      4. 4.1.4. Performance
    2. 4.2. Ethernet and Fast Ethernet
      1. 4.2.1. Ethernet Framing Standards
        1. 4.2.1.1. Ethernet addresses
      2. 4.2.2. Collision Detection
      3. 4.2.3. Hubs, Bridges, and Switches
      4. 4.2.4. Transceivers
    3. 4.3. Token Ring
      1. 4.3.1. MAUs, Bridges, and Switches
    4. 4.4. Gigabit and 10 Gigabit Ethernet
      1. 4.4.1. Gigabit to the Desk
      2. 4.4.2. Gigabit as a Backbone Protocol
    5. 4.5. ATM
      1. 4.5.1. ATM LAN Services
    6. 4.6. FDDI
    7. 4.7. Wireless
    8. 4.8. Firewalls and Gateways
    9. 4.9. Structured Cabling
      1. 4.9.1. Horizontal Cabling
      2. 4.9.2. Vertical Cabling
  7. 5. IP
    1. 5.1. IP-Addressing Basics
    2. 5.2. IP-Address Classes
    3. 5.3. ARP and ICMP
      1. 5.3.1. ARP
      2. 5.3.2. ICMP
    4. 5.4. Network Address Translation
    5. 5.5. Multiple Subnet Broadcast
    6. 5.6. General IP Design Strategies
      1. 5.6.1. Unregistered Addresses
      2. 5.6.2. IP Addressing Schemes
        1. 5.6.2.1. Easily summarized ranges of addresses
        2. 5.6.2.2. Sufficient capacity in each range
        3. 5.6.2.3. Standard subnet masks for common uses
        4. 5.6.2.4. Flexibility for future requirements
      3. 5.6.3. The Default Gateway Question
    7. 5.7. DNS and DHCP
  8. 6. IP Dynamic Routing
    1. 6.1. Static Routing
      1. 6.1.1. Floating Static Routes
    2. 6.2. Types of Dynamic Routing Protocols
    3. 6.3. RIP
      1. 6.3.1. RIP Functionality
      2. 6.3.2. Avoiding Loops
      3. 6.3.3. Split Horizons in RIP
      4. 6.3.4. Variable Subnet Masks
      5. 6.3.5. Redistributing with Other Routing Protocols
    4. 6.4. IGRP and EIGRP
      1. 6.4.1. Basic Functionality
      2. 6.4.2. Active and Stuck-in-Active Routes
      3. 6.4.3. Interconnecting Autonomous Systems
      4. 6.4.4. Redistributing with Other Routing Protocols
    5. 6.5. OSPF
      1. 6.5.1. Area Types
      2. 6.5.2. Area Structures
      3. 6.5.3. Interconnecting Autonomous Systems
      4. 6.5.4. Redistributing with Other Routing Protocols
      5. 6.5.5. IP Addressing Schemes for OSPF
      6. 6.5.6. OSPF Costs
    6. 6.6. BGP
      1. 6.6.1. Autonomous System Numbers
      2. 6.6.2. Where to Use BGP
  9. 7. IPX
    1. 7.1. Dynamic Routing
      1. 7.1.1. Novell RIP and SAP
      2. 7.1.2. EIGRP
      3. 7.1.3. NLSP
    2. 7.2. General IPX Design Strategies
      1. 7.2.1. IPX Addressing Schemes
      2. 7.2.2. RIP and SAP Accumulation Zones
      3. 7.2.3. Efficiency in IPX Networks
  10. 8. Elements of Efficiency
    1. 8.1. Using Equipment Features Effectively
    2. 8.2. Hop Counts
    3. 8.3. MTU Throughout the Network
    4. 8.4. Bottlenecks and Congestion
    5. 8.5. Filtering
    6. 8.6. Quality of Service and Traffic Shaping
      1. 8.6.1. QoS Basics
      2. 8.6.2. Layer 2 and Layer 3 QoS
      3. 8.6.3. Buffering and Queuing
      4. 8.6.4. Integrated and Differentiated Services
        1. 8.6.4.1. Assured Forwarding in Differentiated Services
        2. 8.6.4.2. Expedited Forwarding in Differentiated Services
      5. 8.6.5. IP TOS and Diffserv DSCP
      6. 8.6.6. Traffic Shaping
      7. 8.6.7. Defining Traffic Types
      8. 8.6.8. RSVP
      9. 8.6.9. Network-Design Considerations
  11. 9. Network Management
    1. 9.1. Network-Management Components
      1. 9.1.1. Configuration Management
      2. 9.1.2. Fault Management
      3. 9.1.3. Performance Management
      4. 9.1.4. Security Management
      5. 9.1.5. Accounting Management
    2. 9.2. Designing a Manageable Network
    3. 9.3. SNMP
      1. 9.3.1. How to Monitor
      2. 9.3.2. What to Monitor
      3. 9.3.3. Ad Hoc SNMP
      4. 9.3.4. Automated Activities
    4. 9.4. Management Problems
      1. 9.4.1. DHCP
      2. 9.4.2. Architectural Problems
        1. 9.4.2.1. VLAN structures
        2. 9.4.2.2. LAN extension
        3. 9.4.2.3. Filtering
        4. 9.4.2.4. Firewalls
        5. 9.4.2.5. Redundancy features
        6. 9.4.2.6. Tunnels
      3. 9.4.3. Out-of-Band Management Techniques
  12. 10. Special Topics
    1. 10.1. IP Multicast Networks
      1. 10.1.1. Multicast Addressing
      2. 10.1.2. Multicast Services
      3. 10.1.3. IGMP
      4. 10.1.4. Group Membership
      5. 10.1.5. Multicast Routing
        1. 10.1.5.1. MOSPF
        2. 10.1.5.2. DVMRP
        3. 10.1.5.3. PIM
        4. 10.1.5.4. BGMP
      6. 10.1.6. Network-Design Considerations for Multicast Networks
        1. 10.1.6.1. Multicast administrative zones
        2. 10.1.6.2. Multicast and QoS
    2. 10.2. IPv6
      1. 10.2.1. Header Structure
      2. 10.2.2. Addressing
      3. 10.2.3. Quality of Service
      4. 10.2.4. Security
      5. 10.2.5. Autoconfiguration
      6. 10.2.6. Multicast and Anycast
      7. 10.2.7. Migrating from IPv4 to IPv6
    3. 10.3. Security
      1. 10.3.1. Hub and Switch Port-Level Security
      2. 10.3.2. Filtering Traffic
      3. 10.3.3. IPsec
  13. A. Appendix: Combining Probabilities
  14. Glossary
  15. Bibliography
    1. Books and Articles
  16. Index
  17. About the Author
  18. Colophon
  19. Copyright