SONET与SDH之间的区别

1.同步光网络(SONET)：
SONET代表同步光网络。它是由Bellcore开发的一种通信协议，用于通过使用光纤在相对较大的距离上传输大量数据。通过SONET，可以在光纤上同时传输多个数字数据流。

2.同步数字体系(SDH)：
SDH代表“同步数字体系”，它定义为电信中使用的复用技术。同步光网络是国际上使用的。据说它是SONET的一种变体，并且等同于SDH。它的特性基于高阶多路复用。这些技术提供了比PDH更高的价格和价格，而PDH代表了准同步数字体系。

SONET和SDH之间的区别：

S.No.	SONET	SDH
1.	SONET stands for Synchronous Optical Network.	SDH stands for Synchronous Digital Hierarchy.
2.	It is a digital hierarchy interface for the optical transmission.	It is a network node interface, user-network interface and U reference-point interface to assist BISDN.
3.	It is developed by ANSI (American National Standards Institute).	It is developed by ITU-T (International Telecommunication Union – Telecommunication Standardization Sector).
4.	It has total number of transport overhead of 9×3 = 27 bytes.	It has total number of transport overhead of 9×9 = 81 bytes.
5.	It can transmit data in only synchronous mode.	It can transmit in both synchronous mode and asynchronous mode.
6.	It does not provides better transmission rates as compared to SDH.	It provides better transmission rates as compared to SONET.