tailieunhanh - Lecture Business data communications and networking (8e): Chapter 12 - Jerry Fitzgerald, Alan Dennis

Chapter 12 - Network design. In this chapter, the following content will be discussed: Introduction: traditional network design, building block network design; needs analysis; technology design; cost assessment; designing for network performance. | Business Data Communications and Networking 8th Edition Jerry Fitzgerald and Alan Dennis John Wiley & Sons, Inc Prof. M. Ulema Manhattan College Computer Information Systems 12 - Copyright 2005 John Wiley & Sons, Inc Chapter 12 Network Design 12 - Copyright 2005 John Wiley & Sons, Inc Outline Introduction Traditional Network Design Building Block Network Design Needs Analysis Technology Design Cost Assessment Designing for Network Performance 12 - Copyright 2005 John Wiley & Sons, Inc Traditional Network Design A structured systems analysis and design process Network analysis phase Meeting with users to determine the needs and applications Estimating data traffic on each part of the network Designing circuits needed to support this traffic and obtains cost estimates Implementation phase: Building and implementing the network Takes place a year or two later Works well for static and slowly evolving networks (although costly and time consuming) 12 - Copyright 2005 . | Business Data Communications and Networking 8th Edition Jerry Fitzgerald and Alan Dennis John Wiley & Sons, Inc Prof. M. Ulema Manhattan College Computer Information Systems 12 - Copyright 2005 John Wiley & Sons, Inc Chapter 12 Network Design 12 - Copyright 2005 John Wiley & Sons, Inc Outline Introduction Traditional Network Design Building Block Network Design Needs Analysis Technology Design Cost Assessment Designing for Network Performance 12 - Copyright 2005 John Wiley & Sons, Inc Traditional Network Design A structured systems analysis and design process Network analysis phase Meeting with users to determine the needs and applications Estimating data traffic on each part of the network Designing circuits needed to support this traffic and obtains cost estimates Implementation phase: Building and implementing the network Takes place a year or two later Works well for static and slowly evolving networks (although costly and time consuming) 12 - Copyright 2005 John Wiley & Sons, Inc Inadequacy of Traditional Design Forces making the traditional design approach less appropriate for many of today’s networks: Rapidly changing technology of computers, networking devices and the circuits More powerful devices, much faster circuits Rapidly growing network traffic Difficulty of estimating demand and growth Shorter planning periods (3 years) Dramatic change in the balance of costs Before: Equipment; now: staff Design goal: Minimize the staff time to operate (not the hardware costs) ., use similar standardized equipment for the ease of management 12 - Copyright 2005 John Wiley & Sons, Inc Building Block Network Design A simpler new approach Key concept: Networks that use a few standard components are cheaper (in the long run) than the networks that use many different components Start with a few standard components with ample capacity (without extensive traffic analysis) Called: narrow and deep (few types of devices, used over and over) Result: