1.同步光网络(SONET):
SONET代表同步光网络。这是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。这样,多个数字数据流同时通过光纤传输。
2.密集波分复用器(DWDM):
DWDM代表密集波分复用器。这是将来自不同来源的数据放到光纤电缆上的模块。这些模块通过使用紧密间隔的波长在同一根电缆上承载多个信号,进一步提高了系统带宽和容量。通道间隔减小到1.6 nm或更小。无需更换光纤即可增加容量的经济有效方式。有商业系统可用,具有32个通道及以上的容量。
SONET和DWDM之间的区别:
S.No. | SONET | DWDM |
---|---|---|
1. | SONET is a optical transmission interface. | DWDM is WDM utilizing closely spaced channels. |
2. | In this, SONET aggregates a number of optical signals into higher bit rate signal for transmission over a single fiber using a single wavelength. | In this, DWDM assigns the incoming optical signals to specific frequencies multiplexes them for transport over a single fiber. |
3. | It uses Time division multiplexing(TDM) or statistical TDM. | In this, multiple channels of information carried over the same fiber, each using an individual wavelength. |
4. | These are technologies that are used as a buffer (interfacing) layer for higher layers. | It increases the bandwidth of systems, without using repeaters. |
5. | The channel spacing can be carried over WDM, but not vice versa. | The channel spacing is small 200GHZ. |
6. | The band used are STS-1 with fixed size frames. | The band used are C and L. |
7. | It is easy to isolate one channel from a multiplexed circuit. | There is hundreds of channels is possible. |
8. | The best application is ethernet cabling or public telephone network. | The best application is Long-haul. |