JPH0344718B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a storage program control switch.
This invention relates to a method for maintaining and resuming connected calls when a failure occurs.

(Prior Art) Conventionally, this type of restart method saves the contents of the connection state memory (hereinafter referred to as call information) in the main memory to an external storage device such as a magnetic storage device, and when a failure occurs, the contents of the connection state memory are saved in the external storage device. The call information was read out and set in the main memory, and the line was controlled and reconnected.

Therefore, an external storage device is required to save the call information, and in large-capacity exchanges, an enormous storage capacity is required, making the external storage device expensive. Furthermore, since call information is periodically saved regardless of the connection state, there is a drawback that the processing capacity of the processing device is reduced.

(Object of the Invention) The object of the present invention is to eliminate the above drawbacks by using the link information of the time division switch stored in the storage memory of the time division switch control processor.
An object of the present invention is to provide a connection call holding/resuming method that enables holding/resuming a connected call without providing an external storage device.

(Structure of the Invention) According to the present invention, in a storage program controlled exchange, the connection status of lines (lines and trunks) is stored, and when a change in status occurs, a program determines the next connection to be made based on this connection status. a first processor that identifies and controls the line at any time;
a second processor that stores link information and station information of a time division switch and controls the time division switch based on a link control request from the first processor; A connection call characterized in that the first processor in which the failure occurs is restarted while maintaining call continuity based on link information stored in the storage memory of the second processor when the failure occurs. A hold-resume method is obtained.

(Example) Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a relay system diagram of an example of a storage program control switch to which the present invention is applied.

Line control processor (first processor)
LTC1 to LTC3 are central processing units that monitor the line status and, when a change in status occurs, identify the next connection to be made based on the connection status using a program and control the line. It has main memory devices MM1 to MM3 that store connection states corresponding to connection state numbers and connection destination accommodation position information.

The time division switch control processor (second processor) NMC is a central processing unit that controls the time division switch based on link control requests from the line control processor LTC. It has a main memory device NM4 that stores link information and station information consisting of the accommodation position and the exit accommodation position. Each processor is also connected to a data transfer bus P-BUS.
The configuration is such that data can be transferred between processors.

FIG. 2 is a configuration diagram of the connection state memory of each line stored in the main storage devices MM1 to MM3;
FIG. 3 is a configuration diagram of the link information memory of each link stored in the main memory device MM4.

In Figure 1, line control processor LTC1
is the line circuit of subscribers SUB-A and SUB-B
LC1 and LC2 are connected to the line control processor LTC2, and the line control processor LTC2 is connected to the line circuit LC of subscribers SUB-C and SUB-D.
3. LC4, line control processor LTC3 accommodates trunk circuits TRK-1 and TRK-2 of outgoing trunks TRK-E and TRK-F, respectively;
Main memory device MM1, MM of each line control processor
2. In the connection state memory of the MM 3, the connection state (connection state number, connection destination accommodation location information) of each subscriber and outgoing trunk is stored in correspondence with the line accommodation location.

In addition, the main memory device MM4 of the time division switch control processor NMC contains the time division switch SWNET
The link information indicating the accommodation position of the terminal and the type of terminal (line circuit, trunk circuit) connected to the accommodation position are stored.

Here, as shown in FIG. 1, among subscribers SUB-B and SUB-C in an extension interconnection state, the line control processor LTC1 accommodating the line circuit LC2 of subscriber SUB-B has, for example, a memory. An example of restart processing when a failure occurs due to factors such as a fall will be explained. Note that the line control processors of a large-capacity electronic exchange that accommodates many subscribers usually have redundancy, and it is assumed that each processor is duplicated in this embodiment as well.

When a failure occurs in the line control processor LTC1, the active processor stops, and a standby processor (not shown) sends an identification request for the connection call (SUB-B in the example in Figure 1) via P-SUB. and transfers it to the time division switch control processor NMC. Upon receiving this identification request, the time division switch control processor NMC identifies only the connected call from the link information stored in the main memory device MM4, and as shown in FIG. Read the accommodation position information of the switch SWNET (in the example of FIG. 1, LINK1 shown in FIG. 3). Further, based on this accommodation position information, the type of terminal connected to the accommodation position is identified from the station information stored in the main storage device MM4, and the terminal type is read out. A predetermined connection status number indicating the connection status of the connection call of the line control processor LTC1 is edited from the time division switch SWNET accommodating position information read from the link information and the terminal type information read from the station information. In the example of FIG. 1, the connection state number of subscriber SUB-B, which is the connection call of line control processor LTC1, is
As shown in FIG. 2, "1" indicates the extension interconnection state, and the connection destination accommodation position is "SUB-C".

Thus, the time division switch control processor NMC
edits the connection states of all connected calls (only subscriber SUB-B in the example of FIG. 1) of line control processor LTC1 into connection state numbers, and then transfers the calls to line control processor LTC1 via P-BUS. Line control processor LTC1 that received this data
For the connected call that is in the talking state, the connection state is reset to the connection state memory of the main storage device MM1,
Lines (subscriber lines and trunk lines) that are idle, calling, or waiting for a response are stored in the main memory MM.
1 connection state memory is initialized.

As a result, the faulty line control processor LTC1 is restored to a normal state, and as a result, the restart processing due to the fault occurrence is completed while maintaining call continuity, and the call processing state is restored to the normal state.

(Effects of the Invention) As explained above, the present invention maintains call continuity without providing an external storage device by identifying the connection status of a connected call from the link information and station information of a time division switch. It has the effect of allowing the affected LTC to be restarted while the patient is still suffering.

[Brief explanation of drawings]

Fig. 1 is a relay system diagram of an example of a storage program control exchange to which the present invention is applied, Fig. 2 is a configuration diagram of connection status memory such as lines and trunks stored in the main memory, and Fig. 3 is a diagram of the main memory. FIG. 2 is a configuration diagram of a link information memory of a time division switch stored in a memory. LTC...Line control processor, NMC...Time division switch control processor, MM1 to MM4...
Main memory, P-BUS...Inter-processor data transfer bus, SWNET...Switch network (time division switch), LINK1 to LINK4...Connection link, LC1 to LC4...Line circuit, TRK1
~TRK2...Trunk circuit, SUB-A~SUB-
D... Extension subscriber, TRK-E to TRK-F... Outgoing/incoming trunk.

Claims (1)

[Claims] 1 In a storage program controlled exchange, the connection status of lines (lines and trunks) is stored, and when a change in status occurs, the next connection to be made is identified by a program at any time based on this connection status, and the line is controlled. a second processor that stores link information and station information of a time division switch and controls the time division switch based on a link control request from the first processor; When a failure occurs in the first processor, the accommodation location information and terminal type information of the connected call are identified based on the link information stored in the storage memory of the second processor, and the connection status of the connected call is identified. The first processor is notified of the connection state number indicating the connection state and the connection destination accommodating position, and the first processor maintains call continuity by resetting the connection state of the connected call that is currently in the communication state. A connection call holding/resuming method characterized in that the first processor in which the fault has occurred is restarted while the first processor remains in the state where the fault has occurred.