2. Introduction of SDH
1. It is standard protocol for transmission of data over optical fiber.
2. SDH Technology provide faster and less expensive network.
3. SDH Transmission rate up to 40gb/s.
4. SDH is bandwidth flexible and allow to multivendor network.
5. SDH reliability.
6. It is transmit multiplex light stream onto optical fiber.
7. SDH different type of lower order can be transmit its virtual cantains.
8. The basic unit of SDH is STM(Standard transport module)-1.
9. SDH transport based on multiple of 155.53mb/s.
10. SDH transport mechanism for carrying a large number of PDH.
3. PDH
1. It Is digital multiplexing technique that offer bit rates starting with the basic rate of 2mb/s with
further stage 8,34, and 140 mb/s.
2. It is used in telecom transmission network to transport the large quantities of data.
3. In PDH multiplex and de-m multiplex is very complex .
4. The maximum capacity of PDH 566MB/S.
5. Tolrance is allow in bit rate.
6. PDH does not support hub.
7. PDH allow only point to point configuration.
8. Difficult to integrate interconnecting networking together.
4. SONET
1. SONET is information transmission technique over fiber optical
2. From the information to be transmitted over optical fiber using HDLC standard frame.
3. Provides error checking functionalities.
4. Take care link managment functionalities.
5. SONET is subset of SDH.
6. The unit of SONET is [oc-1] OC IS Optical carrier.
7. It’s min capacity 51.84 mb/s.
8. SONET is 1/3rd of STM-1
