JP2668910B2 - Two-stage time slot allocation method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time slot allocating method for a time division multiplexing apparatus which multiplexes a low-speed line by time division and transmits the multiplexed signal via a high-speed line.

[Conventional technology]

In such a multiplexer, a plurality of time slots are defined, low-speed lines and control channels are allocated to these time slots, and the allocated signals are inserted into each time slot for transmission. Conventionally, the time slot for the control channel and the time slot for the low speed line are allocated at the same time point.

[Problems to be solved by the invention]

However, since the time slots of the control channel and the low-speed line are allocated at the same time, if the line is set by incorrect allocation, erroneous connection will occur when switching between lines is performed, and after that, the opposite connection will occur. Even if an erroneous connection is found between multiplexing apparatuses that perform a connection check, data of another low-speed line appears on an unexpected low-speed line, and there is a problem that the security between the low-speed lines cannot be maintained.

[Means for solving the problem]

In order to solve the above-mentioned problem, the present invention is constituted by the following means.

That is, by allocating a plurality of time slots of a high-speed line connecting the opposing time-division multiplexing devices to each low-speed line, a time slot allocating method for multiplexing and transmitting a plurality of low-speed lines to a high-speed line, Predetermine setting parameters used for line setting for each low speed line are set, and the setting parameters of each low speed line to be multiplexed on each high speed line are classified for each high speed line and Based on the assignment order, an assignment order table is created for each high-speed line that consists of the setting parameters classified for that high-speed line, and a check parameter for checking transmission errors in the assignment order table is assigned to each assignment order by CRC calculation. Generates each from the table and assigns time slots for high-speed lines that connect the specified time division multiplexers. Case, the time slot only the allocation of control channel to a high speed line as a first step,
The normality of the allocation order table is checked between both time division multiplexers by transmitting only the check parameter corresponding to the high-speed line via this control channel between both time division multiplexers, and the check result is normal. Only in the second step, each low-speed line is assigned to the time slot of the high-speed line by the both time-division multiplexer based on the allocation order table.

[Action]

Therefore, in the first step, the allocation order check of both multiplexers is performed via the control channel, and only when this result is normal, the time slot allocation for the low-speed line is performed in the second step, so the erroneous allocation is performed. It is possible to eliminate an error in the line setting due to.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings showing examples.

FIG. 1 is a block diagram showing an equivalent configuration. A multiplex communication system is configured by connecting two opposing high-speed lines 3 to each other, and a multiplex communication system is constructed.
1, 2 are provided with interface units 111 to 113 and 211 to 213 for the plurality of low-speed lines to be accommodated, and control units 101 and 201, and line setting input units 102 and 202.
The control units 101 and 201 control the time slot allocation units 103 and 203 in accordance with the line setting status by the input units 102 and 202, and the control channels 1 and 2 are controlled by the allocation units 103 and 203.
21, 221 are set, and control data is exchanged between the control units 101 and 201 via these and the interfaces 104 and 204 for high-speed lines.

FIG. 2 is a diagram showing the setting status of the check parameters and the time slot allocation order performed by the control units 101 and 201. The setting parameter 400 input as the data of a plurality of bits from the line setting input units 102 and 202 is the channel number of the low speed line. A transmission rate 401 and a connection LINE 402 of a high-speed line used for multiplex transmission are defined for each of CH1 to CH9, which are classified for each high-speed line, and based on this classification, for each high-speed line according to the transmission speed 401. Create the time slot allocation order 410, 420 as a table.

If the transmission speeds are the same, they are arranged according to the order of the channel numbers.

In addition, the allocation order 410, 420 is set between both multiplexers 1 and 2.
Allocation order as being able to check on opposite sides in a short time
Perform CRC calculation of 410, 420, check parameters 411, 42
Calculate 1 for each high-speed line. Note that the CRC operation is to calculate a check parameter specific to the content of a predetermined memory block in a cyclic code check (Cyclic Redundancy Check) method widely used in the communication field and the information processing field. It is calculated using a predetermined generator polynomial. Here, it is used to calculate a check parameter unique to the contents of the allocation order (table) 410, 420.

The control units 101 and 201 are arranged before the time slot allocation.
First, allocation order 410,420 and check parameters 411,421
After determining the above, only the time slot allocation for the control channels 121, 221 is performed as the first step, and the opposite check of the allocation order 410, 420 is performed between them using the check parameters 411, 421 through this, and this result is Low speed line 131 as the second stage only when normal
~ 133,231 ~ 233 time slot allocation for allocation order 410,
Follow 420.

It should be noted that the channel number C of the low speed line in the multiplexers 1 and 2
Although H1 to CH9 are the same and the bypass channel is omitted, the same treatment can be performed when the channel number is different or when the bypass channel is provided.

[Effects of the Invention] As is apparent from the above description, according to the present invention, in the first stage, only the time slots for the control channels are allocated, and the opposing check of the allocation order is performed via the time slots. When the time slot allocation for low-speed lines is performed only in the order of priority and the time slot allocation is performed in two steps, the line settings are not changed by the time slot allocation and the line is switched. In addition, the appearance of data of another low-speed line on an unexpected low-speed line can be completely eliminated, and a remarkable effect can be obtained in the time slot allocation of the time division multiplexing device.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is an equivalent block diagram, and FIG. 2 is a diagram showing a setting situation of allocation order and check parameters. 1,2 ...... Multiplexing device, 3 ...... High speed line, 101,201 ...... Control unit, 102,202 ...... Line setting input unit, 103,104 ...... Time slot allocation unit, 400 ...... Setting parameter, 410,420 ...... Allocation order, 411,421 ...... Check parameter.

Claims (1)

(57) [Claims] 1. A time slot allocation for multiplexing a plurality of low-speed lines to a high-speed line for transmission by allocating a plurality of time slots of a high-speed line for connecting opposing time-division multiplexers to each low-speed line. In the method, the predetermined setting parameters used for line setting are set for each low-speed line, and the setting parameters of each low-speed line to be multiplexed to each high-speed line are classified for each high-speed line, Based on the assignment order of the low-speed line, an assignment order table consisting of setting parameters classified for the high-speed line is generated for each high-speed line, and check parameters for checking transmission errors in the assignment order table are calculated by CRC calculation. Time slot allocation for high-speed lines that connect each specified time division multiplex device, generated from each allocation order table In the first step, only the time slot for the control channel is assigned to the high-speed line, and only the check parameter corresponding to the high-speed line is transmitted between the time division devices via the control channel. The normality of the allocation order table is checked between both time division multiplexers, and only when the check result is normal, the second step is based on the allocation order table and the low speed lines are connected to the high speed lines by the both time division multiplexers. A two-stage time slot allocation method characterized by allocating to each time slot.