Designing Wide Area Networks and Internetworks defines a methodical process for constructing a WAN, or internetwork, from determining requirements and designing the network structure to choosing the most appropriate technologies and evaluating the results. It includes in-depth discussions on such specific topics as: circuit cost optimization techniques; discussing concentration and aggregation, statistical multiplexing, and distance-sensitive tariffs; selecting among such transmission technologies as ISDN, Frame Relay, ATM, SMDS, SONET, and CDPD; security threats and solutions, including authentication, encryption, intrusion detection, decoys, and firewalls; and network and system management protocols and tasks.
Table of Contents
I. BEGINNING THE INTERNETWORK DESIGN PROCESS. 1. Networks and Internetworks Technology Today.
Data Communications and Organizational Competitiveness.
Why Build an Internetwork?
Why Is Building an Internetwork so Challenging?
Challenge 1: Lack of a Coherent, Comprehensible Design Process for Wide Area Internetworks.
Challenge 2: Lack of a Holistic, Integrated View of the Wide Area Internetwork.
Challenge 3: Choosing from among a Potpourri of Data Link Technologies and Carrier Service Options.
Enterprise Networks, Intranets, and Extranets.
Enterprise Networks and Enterprise Internetworks.
Virtual Private Networks (VPNs) and Internet Virtual Private Networks (iVPNs).
What Changes When You Cross a Street?
Evolution and Change.
The Real World Impinges.2. The Internetwork Design Process: Overview.
Phase 1: Definition of Requirements.
Phase 2: Preliminary Design.
Phase 3: Management Review.
Phase 4: Final Design.3. Definition of Requirements.
Identify Access Locations.
Identify Application Requirements.
Internet versus Non-Internet Protocols.
Realtime Voice or Video.
Identify Traffic Patterns.
Determine Performance Requirements.
Throughput and the Traffic Matrix.
Delay and Latency.
Variability of Delay.
Determine Security Requirements.
II. THE PRELIMINARY DESIGN PHASE. 4. Preliminary Design: Overview.
Consider the Existing Network and Its Users.
Steps in the Preliminary Design Phase.
Select the Major Transmission Technologies.
Determine the Levels of Hierarchy.
Identify Possible Backbone Locations.
Create a Preliminary Access Design.
Create Access Homing Designs.
Create a Preliminary Backbone Topological Design.
Create a Preliminary Technical Design.
Demonstrate That Your Design Meets the Requirements.
Analyze Your Costs.5. Circuit Costs and Cost Optimization Techniques.
Elements of Internetwork Costs.
Elements of Circuit Costs.
Cheaper by the Dozen.
Concentration and Aggregation.
Components of IXC Frame Relay Charges.
Applications of Distance-Insensitive Tariffs.
Distance-Sensitive versus Distance-Insensitive Tariffs.
The Bent Straw.6. Selecting Transmission Technologies.
Roles of Each Transmission Technology.
Dedicated Circuits (Leased Lines).
Parallel Circuits and Inverse Multiplexing.
ISDN BRI for Residential Consumer Access.
Concentration of Customers Who Use ISDN BRI or POTS.
Switched Backup for Leased Line Access.
Frame Relay Service Definition.
Frame Relay User Network Interface (UNMI).
Typical Frame Relay Applications in Wide Area Internetworks.
ATM Service Definition and Protocol Interface.
Typical ATM Applications in Wide Area Internetworks.
Applications of ATM.
Switched Multimegabit Data Service (SMDS).
Direct Use of SONET.
IP Data over Cable TV Infrastructure.
ADSL and VDSL.
CDPD and Other Wireless Technologies.
Crytographic Encapsulation over the Public Internet: The iVPN.
Security and Management Implications of VPNs.
Economic Implications of the iVPN.
Suitability of an iVPN.7. Determining the Levels of Hierarchy.
The Concept of Hierarchy.
Partitioning the Internetwork.
What Constitutes a Hierarchical Layer?
How Many Layers?
Hierarchy and Network Topological Design.8. Identifying Backbone Locations.
Higher-Capacity Circuits and Services.
Geographic Expanse.9. Creating a Preliminary Access Design.
Dedicated (Business or Organizational) Access.
Access with Leased Lines.
Access with Multiplexing to Achieve Concentration.
Access with Fast Packet Services.
Switched (Residential) Access.
Bypassing the Carriers.10. Developing Strategies for Access Homing.
The String of Pearls.11. Creating a Preliminary Backbone Topological Design.
Summary of Network Topologies.
Creating the Backbone Design.
Physical Star Network.
Logical Star Network.
Logical Full Mesh Network.
Partial Mesh Network.12. Naming, Addressing, and Routing.
Naming and the Domain Name System (DNS).
Origin of Domain Names.
Servers and Resolvers.
DNS Name Space.
Primary and Secondary DNS.
Zones and Delegation.
The IN-ADDR.ARPA Domain.
More Exotic Uses of the Domain Name System.
Networks and Subnetworks.
Classless Inter-Domain Routing (CIDR).
Developing the Address Plan.
Security and the Addressing Plan.
Internet Protocol Version 6 (IPv6).
Host Support for Redundancy.
Exterior Routing.13. Security.
Threats to Network Security.
Fundamentals of Network Security.
Authentication of Dialup Users (PAP, CHAP, and RADIUS).
Link Layer Encryption.
Network Layer Security (IPSEC).
Session Layer Security: The Secure Socket Layer (SSL).
Application Layer Security (PGP, Kerberos, and X.509 Certificates).
Limitations of Perimeter Security.
A Castle with Inner and Outer Walls.14. The Public Internet: Unique Design Considerations.
Evolution of Today's Internet.
National Service Providers and Internet Service Providers.
Network Access Points.
Transit Service among Regional ISPs.
The Very High Speed Backbone Network Service (vBNS).
The Route Arbiter (RA) Project.
Structure of the Internet Today.
Direct and Shared Interconnections (Public and Private Peering).
Traffic Characterization in Light of Shortest-Exit Routing.
International Internet Traffic Flows.
Internet Access.15. Network Management.
Network Management versus System Management.
Network Management Protocols.
Network Management in Perspective.16. Validation of the Design against the Requirements.
Measures of Performance.
Tools for Evaluating Performance.
Queuing Models, Delay, and Latency.
Verification of Functionality.
Availability as a Function of MTBF and MTTR.
Computing Availability for Multiple Components.
More Complex Analyses.
III. THE MANAGEMENT REVIEW PHASE. 17. Management Review: Financial Analysis.
Circuits and Services.
Ancillary Costs Associated with New Services.
Expenses over Time.
Revenues: The Benefits.
Profitability: Calling the Shots.
Hazards in Estimating Profitability.
Dealing with an Insufficient Profitable Network.
IV. THE FINAL DESIGN PHASE. 18. Final Design Overview. 19. Selection of Carriers and Vendors.
Interexchange Carriers (IXCs).
Local Exchange Carriers (LECs).
Carriers of Cellular and Wireless Communications.
The Equipment Vendors.
WAN Switches: Frame Relay, SMDS, and ATM.
The Request for Proposal (RFP).
Types of RFPs.
Hints in Constructing an RFP.Index. 0201695847T04062001
Speedy, reliable, and secure communications are essential for maintaining an organizationis competitiveness, and Wide Area Networks and Internetworks are quickly proliferating in order to meet this need. Building such a network, however, can be a daunting task; a large investment is required, and organizations must navigate through a dizzying array of technological and design options.
Designing Wide Area Networks and Internetworks clarifies this complex task by outlining a top-down, step-by-step process for constructing a WAN or internetwork that is effective for your organization. This book will guide you through the steps of determining requirements, designing the network structure, choosing appropriate technologies, and evaluating results. The authoris practical approach distills exactly what you need to know about networking theory and technological background in order to accomplish a given task.
On the financial side, it is important to note that the difference between a good design and a poor one can represent many millions of dollars per year. This book presents a quantitative, business-oriented approach to network design. It focuses on the economic and performance characteristics of various network technologies and carrier service options, and explains the conditions for which each is optimal.
J. Scott Marcus is Chief Technology Officer (CTO) for GTE Internetworking. Previously, he was Director of Network Architecture at BBN Corporation.