JPH0374950A - Data communication equipment - Google Patents

Abstract

PURPOSE:To manage a reference data having been used precedingly and the time releasing the reference data by using time information managed by the equipment as the reference data for transport connection identification assigned to a frame generated at the establishment of the transport connection. CONSTITUTION:A transport connection establishing request is received by a transport service primitive reception means 1 and given to a transport connection management means 2. The means 2 generates a frame for establishing the connection to request the reference data to be assigned to the transport connection to a reference management means 3. The means 3 uses a time information acquisition means 4 to acquire the time information and returns the information to the transport connection management means 2. The means 2 gives the generated frame to a network service primitive publication means 5, which publicates the network service primitive to request network data transfer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is utilized in a data communication device of a system implementing a transport layer function of open system interconnection.

〔overview〕

In a data communication device, the present invention uses time information managed by the device as a reference for identifying a transport connection, which is assigned to a frame created when a transport connection is established, so that the reference can be used together with previously used references. This eliminates the need to manage the freed time and unfreeze the reference when the frozen time has elapsed, and the frozen time can be guaranteed even if the management information disappears due to a failure. .

[Conventional technology]

Conventionally, data communication devices have used sequential integers as references to identify transport connections established with other systems.

[Problem that the invention seeks to solve]

However, in such conventional data communication devices, the reference of a transport connection can cause problems such as processing time in the other system and retransmission of frames from the other system even after the transport connection corresponding to the reference is released. If a sequential integer is used as a reference because it must not be reused for a certain period of time, the time when the transport connection corresponding to that reference was released and the freeze corresponding to that transport connection. There was a problem of having to manage time. Also, −
When reusing a reference that has been used several times, the problem requires control to select a reference whose freeze time corresponding to the transport connection has passed since the time when the transport connection that previously used the reference was released. There was a point. Furthermore, if a system failure occurs and the management information disappears, there is a problem that the above-mentioned freezing time is not guaranteed.

The present invention solves the above problem, and manages the release time and freeze time of the reference along with previously used references, and unfreezes the reference when the freeze time has elapsed. It is an object of the present invention to provide a data communication device that does not require processing and can guarantee freezing time even if management information disappears in the event of a failure.

[Means for solving problems]

The present invention provides transport service primitive reception means for receiving a transport connection establishment request;
Transport connection management means that inputs the information received by this transport service primitive reception means and creates a frame for establishing a connection based on this information, and issues a network service primitive based on the output of this transport connection management means. A data communication device comprising: a network service primitive issuing means for transmitting a network service primitive to the transport connection management means; The connection management means is characterized in that it includes means for requesting a reference for identifying a transport connection to be allocated to the frame, and means for allocating the returned reference to the frame.

[Effect]

The transport connection management means requests a reference for identifying the transport connection to be assigned to the frame from the reference acquisition means. The reference acquisition means acquires time information in the device, converts it into a frame format, and sends it back to the transport connection management means.

The transport connection management means assigns this returned reference to the frame. With the above operation, the free time of the reference is managed together with the previously used reference, there is no need to unfreeze the reference when the freeze time elapses, and management information is saved in the event of a failure. Freezing time can be guaranteed even if the

〔Example〕

Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram of a data communication device according to an embodiment of the present invention. A transport service primitive reception means 1 that receives a transport connection establishment request, and a transport connection management means 2 that inputs information received by the transport service primitive reception means 1 and creates a frame for establishing a connection based on this information. and network service primitive issuing means 5 for issuing network service primitives based on the output of the transport connection management means 2.

Here, the present invention is characterized by the reference management means 3 and the time information acquisition means as a reference acquisition means for acquiring time information based on a reference request from the transport connection management means 2, converting it into the above-mentioned frame format, and sending it back. 4, the transport connection management means 2 includes means for requesting a reference for identifying a transport connection to be allocated to the frame, and means for allocating the returned reference to the frame.

The operation of the data communication device having such a configuration will be explained. FIG. 2 is a flowchart showing the operation of the data communication device of the present invention.

In FIGS. 1 and 2, the transport service primitive reception means 1 receives a transport connection establishment request from a transport service user (31). The transport service primitive reception means 1 passes the received information to the transport connection management means 2 (S2). The transport connection management means 2 generates a frame for establishing a connection based on the given information (S3). Then, it requests the reference management means 3 for a reference to be assigned to that transport connection (S4). The reference management means 3 acquires time information using the time information acquisition means 4, converts the information into a form that can be placed in a frame, and returns it to the transport connection management means 2 (S5).

The transport connection management means 2 sends the generated frame to the network service primitive issuing means 5.
The network service primitive issuing means 5 issues a network service primitive requesting network data transfer to the network service provider (S7).

〔Effect of the invention〕

As explained above, the present invention manages previously used references as well as the time when the reference was released and its freezing time, and executes the process of unfreezing the reference when the freezing time has elapsed. It has the excellent effect of guaranteeing freezing time even in the event of a failure.

Therefore, great advantages are expected in systems that relatively frequently establish and release connections.

Means, 2... Transport connection establishment means,
3... Reference management means, 4... Time information management means, 5... Network service primitive issuing means.

Claims (1)

[Claims] 1. Transport service primitive reception means that receives a transport connection establishment request; Information received by the transport service primitive reception means is input and a frame for establishing a connection is created based on this information. and a network service primitive issuing means that issues a network service primitive based on the output of the transport connection management means, based on a reference request of the transport connection management means. The transport connection management means includes means for requesting a reference for identifying a transport connection to be allocated to the frame, and a means for requesting a reference for identifying a transport connection to be allocated to the frame, and a means for requesting a reference for identifying a transport connection to be allocated to the frame. and means for assigning a reference to the frame.