Transmission system

Abstract

A transmission system is provided which multiplexes and transmits synchronous data and asynchronous data, while maintaining the communication quality required of synchronous data and of asynchronous data respectively. A tag having information used to identify the data as synchronous data or as asynchronous data is added to both synchronous data and to asynchronous data. Tags added to each data item are extracted, and based on the information contained in the tag, each data item is identified as synchronous data or as asynchronous data, and synchronous data is transferred to a time-division switch, while asynchronous data is transferred to a packet switch.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a transmission system with a ring configuration;

FIG. 2 shows an example of the configuration of a transmission system when converting asynchronous data into synchronous data and transmitting the data;

FIG. 3 shows an example of the configuration of a transmission system when converting synchronous data into asynchronous data and transmitting the data;

FIG. 4 shows an example of the configuration of a transmission system when separately processing and transmitting in parallel synchronous data and asynchronous data;

FIG. 5 shows a first configuration example of the transmission system of an aspect of the invention;

FIG. 6 shows a second configuration example of the transmission system of an aspect of the invention;

FIG. 7A shows synchronous data and asynchronous data with tags added;

FIG. 7B shows synchronous data and asynchronous data with tags added;

FIG. 7C shows synchronous data and asynchronous data with tags added;

FIG. 8 shows a third configuration example of the transmission system of an aspect of the invention;

FIG. 9 shows a configuration example of a straight-through processing unit 75;

FIG. 10 shows a fourth configuration example of a transmission system of an aspect of the invention, corresponding to a network with redundancy;

FIG. 11 shows a fifth configuration example of a transmission system of an aspect of the invention, corresponding to a network with redundancy;

FIG. 12 shows a sixth configuration example of a transmission system of an aspect of the invention, corresponding to a network with redundancy;

FIG. 13 shows a configuration example of a low-speed side interface 30; and, FIG. 14 shows another configuration example of a low-speed side interface 30.

Claims

1. A transmission system receiving, from a node on a transmission path, multiplexed data in which synchronous data and asynchronous data are multiplexed and unified as either frames of synchronous data or as frames of asynchronous data, comprising: a first switch switching synchronous data;a second switch switching asynchronous data; anda distribution control unit extracting tags added to the data, identifying the data as synchronous data or as asynchronous data based on information included in tags to identify whether the data is synchronous data or asynchronous data, transferring synchronous data to said first switch, and transferring asynchronous data to said second switch.

2. The transmission system according to claim 1, further comprising: a tag insertion unit inserting, into synchronous data output in the direction of said transmission path node from said first switch, said tag indicating that the data is synchronous data, and inserting, into asynchronous data output in the direction of said transmission path node from said second switch, said tag indicating that the data is asynchronous data; anda multiplexing unit performing multiplexing unified as frames of either synchronous data or asynchronous data with said tags inserted thereinto, and transmitting said frames to the node of said transmission path.

3. A transmission system receiving from a node on a transmission path multiplexed data in which synchronous data and asynchronous data are multiplexed and unified as frames of the asynchronous data, comprising: a packet switch switching asynchronous data; anda straight-through processing unit extracting tags added to separated data, transmitting first data which is synchronous data and is not addressed to said packet switch to the node of said transmission path, and transferring second data other than said first data to said switch based on information to identify whether the data is synchronous data or asynchronous data and destination information included in tags.

4. The transmission system according to claim 3, wherein said packet switch processes, with priority, data which is synchronous data and is said second data, and which is addressed to said switch.

5. The transmission system according to claim 3, comprising a frame conversion unit converting synchronous data, output from said packet switch to a low-speed interface side, from frames of asynchronous data into frames of synchronous data, wherein said frame conversion unit has memory which absorbs delay fluctuations of synchronous data output from said packet switch.

6. The transmission system according to claim 5, wherein said memory is common with hitless switching memory provided in said low-speed interface.

7. The transmission system according to claim 3, wherein, when a plurality of said packet switches are provided for network redundancy, or when said packet switches are divided, a bridge processing unit to transfer data from one packet switch to another packet switch is provided, and wherein data transmission is performed between said packet switch and said straight-through processing unit via said bridge processing unit.