Top-Down Network Design (3rd Edition)
Format: PDF / Kindle (mobi) / ePub
The purpose of Top-Down Network Design, Third Edition, is to help you design networks that meet a customer’s business and technical goals. Whether your customer is another department within your own company or an external client, this book provides you with tested processes and tools to help you understand traffic flow, protocol behavior, and internetworking technologies. After completing this book, you will be equipped to design enterprise networks that meet a customer’s requirements for functionality, capacity, performance, availability, scalability, affordability, security, and manageability.
This book is for you if you are an internetworking professional responsible for designing and maintaining medium- to large-sized enterprise networks. If you are a network engineer, architect, or technician who has a working knowledge of network protocols and technologies, this book will provide you with practical advice on applying your knowledge to internetwork design.
This book also includes useful information for consultants, systems engineers, and sales engineers who design corporate networks for clients. In the fast-paced presales environment of many systems engineers, it often is difficult to slow down and insist on a top-down, structured systems analysis approach. Wherever possible, this book includes shortcuts and assumptions that can be made to speed up the network design process.
Finally, this book is useful for undergraduate and graduate students in computer science and information technology disciplines. Students who have taken one or two courses in networking theory will find Top-Down Network Design, Third Edition, an approachable introduction to the engineering and business issues related to developing real-world networks that solve typical business problems.
Changes for the Third Edition
Networks have changed in many ways since the second edition was published. Many legacy technologies have disappeared and are no longer covered in the book. In addition, modern networks have become multifaceted, providing support for numerous bandwidth-hungry applications and a variety of devices, ranging from smart phones to tablet PCs to high-end servers. Modern users expect the network to be available all the time, from any device, and to let them securely collaborate with coworkers, friends, and family. Networks today support voice, video, high-definition TV, desktop sharing, virtual meetings, online training, virtual reality, and applications that we can’t even imagine that brilliant college students are busily creating in their dorm rooms.
As applications rapidly change and put more demand on networks, the need to teach a systematic approach to network design is even more important than ever. With that need in mind, the third edition has been retooled to make it an ideal textbook for college students. The third edition features review questions and design scenarios at the end of each chapter to help students learn top-down network design.
To address new demands on modern networks, the third edition of Top-Down Network Design also has updated material on the following topics:
¿ Network redundancy
¿ Modularity in network designs
¿ The Cisco SAFE security reference architecture
¿ The Rapid Spanning Tree Protocol (RSTP)
¿ Internet Protocol version 6 (IPv6)
¿ Ethernet scalability options, including 10-Gbps Ethernet and Metro Ethernet
¿ Network design and management tools
network engineers, and any other stakeholders. Also, determine whether the customer’s definition of success will change as yearly fiscal goals change. In addition to determining the criteria for success, you should ascertain the consequences of failure: ■ What will happen if the network design project fails or if the network, when installed, does not perform to specification? ■ How visible is the project to upper-level management? ■ Will the success (or possible failure) of the project be
newspaper the day after the 9/11 attacks was because it had learned from 1990s power outages about the need to disperse critical functions across many different sites. In the current business environment, security and disaster recovery should be considered with every network design choice, and the network designer must propose solutions that provide resiliency and stability. A systematic and modular design process, as taught in this book, is even more important than it once was, as networks
97 Documenting Application-Usage Patterns 99 Refining Estimates of Traffic Load Caused by Applications Estimating Traffic Load Caused by Routing Protocols 101 99 90 x Top-Down Network Design Characterizing Traffic Behavior 101 Broadcast/Multicast Behavior Network Efficiency Frame Size 101 102 103 Windowing and Flow Control Error-Recovery Mechanisms 103 104 Characterizing Quality of Service Requirements ATM QoS Specifications 105 106 Constant Bit Rate Service Category 107
branch office but not beyond. Over time, you’ll end up with a hodgepodge of distributed access control lists (ACL) and firewalls, which complicates policy enforcement. It also greatly raises costs if you want to use intrusion detection systems (IDS) and other security technologies. Similarly, some remote offices with IPsec VPN connectivity are shifting away from split access at the remote sites where users have local access to the Internet in addition to remote IPsec access to corporate
redundancy in a campus network design. File, web, Dynamic Host Configuration Protocol (DHCP), name, and database servers are all candidates for redundancy in a campus design, depending on a customer’s requirements. In a network that supports Voice over IP (VoIP), the servers that provide the mapping between a phone number and an IP address and handle call processing should be provisioned in a redundant fashion. Cisco Unified Communications Manager, for example, supports a redundancy group where