TAILIEUCHUNG - Giới thiệu về IP và ATM - Thiết kế và hiệu suất P3

SHARING RESOURCES A simple answer to the question ‘Why have a network?’ is ‘To communicate information between people’. A slightly more detailed answer would be: ‘To communicate information between all people who would want to exchange information, when they want to’. Teletraffic engineering addresses the problems caused by sharing of network resources among the population of users; it is used to answer questions like: ‘How much traffic needs to be handled?’ ‘What level of performance should be maintained?’ ‘What type of, and how many, resources are required?’ ‘How should the resources be organized to handle traffic?’. | Introduction to IP and ATM Design Performance With Applications Analysis Software Second Edition. J M Pitts J A Schormans Copyright 2000 John Wiley Sons Ltd ISBNs 0-471-49187-X Hardback 0-470-84166-4 Electronic 3 Teletraffic Engineering the economic and service arguments SHARING RESOURCES A simple answer to the question Why have a network is To communicate information between people . A slightly more detailed answer would be To communicate information between all people who would want to exchange information when they want to . Teletraffic engineering addresses the problems caused by sharing of network resources among the population of users it is used to answer questions like How much traffic needs to be handled What level of performance should be maintained What type of and how many resources are required How should the resources be organized to handle traffic MESH AND STAR NETWORKS Consider a very simple example a telephone network in which a separate path with a handset on each end is provided between every pair of users. For N users this means having N N 1 2 paths and N N 1 telephone handsets. A simple cost-saving measure would be to replace the N - 1 handsets per user with just one handset and a 1 to N - 1 switch Figure . A total of N handsets and N switches is required along with the N N 1 2 paths. If all N users are communicating over the network at the same time . there are N 2 simultaneous calls or N 1 2 if N is odd then 1 N 1 of the paths and all of the handsets and switches would be in use. So in a network with 120 users for example the maximum path utilization is just under 1 and handset and switch utilization are both 100 . 46 TELETRAFFIC ENGINEERING Contrast this with a star network where each user has a single handset connected to two N to 1 switches and the poles of the switches are connected by a single path Figure . In this example there are N handsets N 1 paths and 2 switches. However only 2 users may communicate at any one time .

• Kĩ thuật Viễn thông
• Thiết kế IP
• hiệu suất IP
• thiết kế ATM
• hiệu suất ATM
• công nghệ Mode
• lưu lượng IP WDM
• thiết kế
• lưu lượng IP
• tín hiệu
• kết nối IP
• dung lượng băng thông
• viễn thông
• mạng máy tính
• mạng IP WDM