计算机局域网英语教学课件.ppt

Telephone Basics Telephone Network Summary Telephone Network Summary Telephone Network Summary Common Channel Signaling Common Channel Signaling Interoffice Facilities Developments Dense Wave Division Multiplexing (DWDM) Local Loop Developments Local Loop Developments Local Loop Developments Local Loop Developments Local Loop Administration and Maintenance Switching System Architecture Switching Maintenance Interoffice Facility Maintenance Network Administration A Word About Records Simple Installation Simple Installation Simple Installation Simple Installation Do you have any Classroom Discussion Feeder Distribution-F2 Local Loops F1 445 Interface The local loop plant is made up up mostly copper facilities (although fiber is beginning to appear in feeder routes) and interface points to provide flexibility. Local Loops Terminal 960 942 837 445 888 Local Calls LD Calls Local Tandem Toll Tandem To LD Routes Local Network The local network is made up of electronic end office switches and interoffice facilities (mostly DS-1s over fiber) and usually will have one or more tandem switches. Feeder Distribution-F2 Local Loops F1 960 942 837 445 888 Local Calls LD Calls Interface Local Tandem Toll Tandem To LD Routes The local loop plant is made up up mostly copper facilities (although fiber is beginning to appear in feeder routes) and interface points to provide flexibility. Local Network The local network is made up of electronic end office switches and interoffice facilities (mostly DS-1s over fiber) and usually will have one or more tandem switches. 960 942 837 888 Local Tandem Toll Tandem Local Network Fully duplicated signaling switches called Signal Transfer Points (STPs). Digital links from each switch to each STP Information Transfer Between Switching Nodes 445 Set Up Initial Address Message Alert Address Complete Message Audible Ring STP Local Exchange Signaling Path Talking Path Interexchange Trunk (Talk Path) Local Exchange Data packets Simple Call Set-Up