JPH01170138A - Data transmission control system - Google Patents

Abstract

PURPOSE:To effectively utilize a line and to easily change a line assignment by adding destination information in a word unit for each word, sending it from a terminal station, identifying the destination information by means of a branching device, and sending it to the terminal station corresponding to the destination information in the word unit. CONSTITUTION:A frame is added from a terminal station A to a distributing part 14 of a branching device 1, a frame synchronizing pattern FAW is detected, a frame synchronization is obtained, and a destination code ADC of each word next to the frame synchronizing pattern FAW is identified by a destination processing part 20. When a data string D1-n arranged to a low order group is to a terminal station B destination and other data strings are to a terminal station C destination, since the terminal station B destination is identified by the destination code ADC in data D1-1, data D1-1-D1-11 are distributed to a multiplexing part 12 according to the order of the words in the frame, and other data are distributed to a multiplexing part 13.

Description

[Detailed Description of the Invention] [Summary] A data transmission control method that multiplexes data in units of words and configures frames to transmit data. For the purpose of easily changing line assignments, etc., multiplexing is performed in units of words in a system in which terminal stations at multiple points are connected by transmission paths via branching equipment. A frame is configured, and the word-based destination information is added word by word or intensively within the frame and sent from the terminal station, and the branching device identifies the destination information and sends it to the destination. The configuration is such that branch transmission is performed in word units to terminal stations corresponding to information.

[Industrial application field]

The present invention relates to a data transmission control system that multiplexes data in units of words and configures frames to transmit data.

2. Description of the Related Art A transmission system is known in which a plurality of terminal stations located at remote locations are connected by a transmission path via a branching device, and the terminal stations communicate with each other. In such transmission systems, it is desired to improve transmission efficiency.

[Conventional technology]

A transmission system that connects a plurality of terminal stations via a branching device is, for example, a plurality of terminal stations 31, 32, as shown in FIG.
．． 33 is connected via a branching device 34 to transmission lines 35, 36 .
37, and the work of laying the transmission line is easier compared to the case where transmission lines are provided between the terminal stations 31 and 32, between the terminal stations 32 and 33, and between the terminal stations 31 and 33. It is something. Therefore, in the optical submarine cable transmission system, each terminal station 3 is
A configuration in which 1.32.33 are branched and connected is adopted.

The terminal stations 31, 32, and 33 each accommodate a plurality of lines and have functions of multiplexing and demultiplexing. In addition, the branching device 34 is equipped with a configuration for switching the transmission path in the event of a failure in the transmission path 35, 36, or 37, so that communication is possible between two terminal stations via a healthy transmission path. .

[Problem that the invention seeks to solve]

As mentioned above, in the transmission system, in the branching device 34,
Each terminal station 31.3 is equipped with functions for multiplexing and demultiplexing.
It is conceivable to separate the data from 2.33, multiplex them according to their destinations, and send them out. In this case, it is necessary to use the line effectively and to be able to flexibly deal with the occurrence of a failure or an increase in the amount of data transmission.

SUMMARY OF THE INVENTION An object of the present invention is to make effective use of lines and to easily change line assignments in response to line demand or in the event of a failure.

Means for Solving Problem c] The data transmission control system of the present invention multiplexes data and transmits it as a frame structure, and will be explained with reference to FIG.

In a system in which terminal stations A, B, and C at multiple points are connected by a transmission path 2.3.4 via a branching device 1, a frame is constructed by multiplexing each word, and destination information is transmitted in each word. is intensively added to each word or within a frame and sent from the terminal station, and the branching device identifies the destination information and branches and sends out the word to the terminal station in units of words.

[Effect]

mB I C, mB I P, m as transmission codes
One word is an integer multiple of an m+l bit or n bit block in a code format such as BnB, and destination information is added to each word for multiplexing, or destination information is added intensively to the beginning of the frame. and multiplex it, and in the branching device 1,
By identifying the destination information and sending it to the terminal station that corresponds to the destination information, and creating a frame structure, the line can be used effectively, and by changing the destination information, it is easier to deal with line demand, etc. Can be done.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is an explanatory diagram of the frame structure of an embodiment of the present invention, in which 24BIP is used as the code format, the low order group bit rate is 44.736 Mb/S, and the high order group bit rate is 59 Mb/S.
1.2Mb/S, one frame shown in (a) is 332
The case is 5 bits, where FAW is the frame synchronization pattern, P is the parity bit, C is the stuff control bit,
S is stuff bit, ADC is destination code, T is order wire bit, and DATA is data. Also Di-1~
D12-11 is data constituting each word, Dm-1~
Dm-11 is a data string of a higher order group, DI-n to D12-n
(b) shows a word in which the destination code ADC is added to the data DATA. An order wire bit T is inserted in this word.

This shows the case where 24BIP, which is a code format in which 1 bit of parity bit P is added to each of 24 bits of data D1-1 to D12-11, is used, and therefore, 25 bits of l block are taken as one word. Furthermore, the data strings Dm-1 to Dm-11 of the higher-order group each have a configuration of 300 bits, and when organized into lower-order groups, the data string DI-n-
012-n are each 275 bits.

In addition, the destination code ADC is added to each word at the beginning of a data string arranged into a low-order group, and the destination code ADC is added only to each word in the data string Dm-1 of a high-order group.
is added, and the other data string Dm of the higher-order group
-2 to Dm-11 include only data. Also, for the destination code ADC, 2 bits is sufficient in a transmission system with a 3 terminal station configuration, but this example shows a case where the destination code ADC is made up of 8 bits so that each terminal station can be identified in a pattern even if there is a bit error. .

Each terminal station configures and sends a frame as shown in (a), and the branching device uses a frame synchronization pattern FA.
W is detected, frame synchronization is established, and the next word (data D1-1.02-1. of higher order group code string Dm-1.
・Destination code AD added to the D12-1 word)
C and distributes each word within the frame according to its destination code ADC.

FIG. 3 is a block diagram of the main parts of the branching device according to the embodiment of the present invention, and shows the case where three terminal stations A, B, and C are connected, 11 to 13 are multiplexing units, and 14 to 16 are distribution units. It is.

Further, 17 to 19 are buffer memories, and 20 to 22 are destination processing units.

For example, the frame shown in FIG. Destination code ADC is identified by the destination processing unit 20. For example, if the data string DI-n organized into a low-order group is addressed to terminal station B, and the other data strings are addressed to terminal station C, the data string in data DI-1 is Since it is identified that the destination is terminal B by the destination code ADC, data D1-1 to DI-11 are distributed to the multiplexer 12 based on the order of words in the frame, and other data are distributed to the multiplexer 13. distributed to.

In other distribution units 15.16, the destination code ADC is identified in each destination processing unit 21.22, and distributed to multiplexing units 11-13 corresponding to terminal stations A, B, and C according to the destination code ADC. .

In addition, the multiplexing units 11 to 13 transfer data distributed in word units from the distribution units 14 to 16 to buffer memories 17 to 19.
The signals are multiplexed and sent to the respective terminal stations A, B, and C.

FIG. 4 is an explanatory diagram of the frame structure of another embodiment of the present invention, showing a case where the same high-order group and low-order group bit rates and code formats as in the embodiment shown in FIG. 2 are used; (a) (
(b) is the frame synchronization word F, (C1 indicates the first word when organized into lower order groups, ADCC is the destination control code, AUX is the auxiliary bit, and the frame synchronization word is sent to the transmission path.) F is the frame synchronization pattern FAW, destination control code ADCC, parity and P
This shows the case where

A destination control code ADCC is centrally provided in the frame synchronization word F at the beginning of the frame to indicate the destination of the word within the frame, and corresponds to the case where destination information is centrally added within the frame. Synchronization pattern FAW
is 12 bits, the destination control code ADCC is 12 bits.
The bit structure can indicate multiple destinations for words within a frame.

Furthermore, the data string Di when organized into lower order groups in the embodiment shown in FIG.
An auxiliary bit AUX is provided in the first word of -nxD12-n instead of the destination code, and can be used to transmit various information. Note that it is also possible to omit this auxiliary bit AUX.

When using the frame configuration of this embodiment, the branching device uses the frame synchronization pattern FA of the frame synchronization word F.
Frame synchronization is achieved by W, the destination control code ADCC of the frame synchronization word F is detected and identified in the destination processing units 20 to 22, and each word in the frame is distributed according to the identified destination. .

FIG. 5 is a detailed explanatory diagram of the present invention, showing a case where data is transmitted from station 0 to stations A and B using the frame structure shown in FIG. Data from station 0 to stations A and B is sent in word units al, bl, a2 . b2,... are multiplexed to form a frame, and the frame synchronization pattern FA is placed at the beginning.
Add W and send. At that time, the destination code ADC is added to the words al and bl.

The branching device detects the frame synchronization pattern FAW to perform frame synchronization, separates and identifies the destination code ADC from the next words al and bl of the frame synchronization pattern FAW, and identifies the word al from the order of the words in the frame.
, a2. a3. ... to station A, and word bl
, b2. b3. ... is distributed to station B.

FIG. 6 is an explanatory diagram of the distribution and multiplexing operation of the present invention;
The case where data is transmitted from the station to stations B and C, and from station B to stations A and C, respectively, is shown. In this case, the destination code ADC is added to the next words cl and bl of the frame to which the frame synchronization pattern FAW is added to the beginning from station A, and the next word of the frame to which the frame synchronization pattern FAW is added to the beginning from station B is added. A destination code ADC is added to al and cl and sent.

The branching device distributes the words in the frame using the destination code ADC, and the words bl from the A station are sent to the B station.
b2. b3. . . , and the words al, a2 . . . from the B station are distributed to the A station. a3. ..., and the word c L c L c from stations A and B is distributed to station C.
2*CL... are distributed and multiplexed.

FIG. 7 is an explanatory diagram of the destination change operation according to the embodiment of the present invention,
A case will be shown in which data is transmitted from station C to stations A and B. Station C sends out a frame with a frame synchronization pattern FAW added to the beginning. In that case, word a addressed to station A
ll, a12. ...+, a21. a22.・+
+, a31. a32゜... and word b11 addressed to B station
．． b12. ... are multiplexed to form a frame.

Therefore, the line capacity ratio is A:B-3:1, and in the branching device, words a11. a211 a31, b
Identify the destination code ADC attached to ll, and
, will be distributed to station B.

When changing such a line capacity ratio to A:B=1:3 due to an increase in the amount of transmission between stations C and B, the word a21 . a22. ....

a31. a32. ... is changed to be addressed to B station. That is, word a21. Destination code A added to a31
Change the DC from station A to station B. Therefore, in the branching device, word a11. a12. ... is distributed to station A,
Word bll, b12. . . to the B station, and the word b21 . . . with the destination code ADC changed. b
22. ..., b31, b32. ... is distributed to station B.

Therefore, line allocation in the event of a change in line demand or a failure can be easily handled by changing the destination code. It is also possible to change the destination code ADC or destination control code ADCC for each frame. If the number of bits of such destination information is small, it is also possible to add it to each word.

Further, in the above embodiment, three terminal stations A, B, and C are connected via a branching device.
This shows the case of a transmission system where
Even when four or more terminal stations are connected, by adding destination information to each terminal station, data transmission can be performed by distributing and multiplexing in word units.

〔Effect of the invention〕

As explained above, the present invention configures a frame by multiplexing word by word, thereby making it possible to
．． 3.4 and above can transmit data continuously, so it can be used effectively. In addition, destination information such as word-based destination code ADC or destination control code ADCC is intensively added to each word or within a frame.
,B.

C sends out, and branching device L branches out according to the destination information, and by changing the destination information,
Since line assignment can be easily changed, it is possible to flexibly deal with increases in line demand. Furthermore, when a fault occurs, control can be performed so that no line is allocated to the faulty transmission line or terminal station.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the principle of the present invention, FIG. 2 is an explanatory diagram of a frame configuration of an embodiment of the present invention, FIG. 3 is a block diagram of main parts of a branching device of an embodiment of the present invention, and FIG. FIG. 5 is a diagram explaining the distribution operation of the embodiment of the invention, FIG. 6 is a diagram explaining the distribution and multiplexing operation of the embodiment of the invention, and FIG. 7 is a diagram explaining the distribution and multiplexing operation of the embodiment of the invention. FIG. 8 is an explanatory diagram of the destination change operation according to the embodiment of the invention, and FIG. 8 is an explanatory diagram of the transmission system. A, B, C are terminal stations, 1 is a branching device, 2.3.4 is a transmission path, FAW is a frame synchronization pattern, P is a parity bit, ADC is a destination code, ADCC is a destination control code, 1
1 to 13 are multiplexing sections, 14 to 16 are distribution sections, 17 to 19
is a batza memory, and 20 to 22 are destination processing units.

Claims (1)

[Claims] In a system in which terminal stations (A, B, C) at multiple points are connected by transmission lines (2, 3, 4) via a branching device (1), multiplexing is performed in units of words. to form a frame, and the destination information in word units is added word by word or intensively within the frame and sent from the terminal station, and the branching device (1) transmits the destination information. A data transmission control method characterized by identifying and branching out in word units to a terminal station corresponding to the destination information.