JP3144606B2 - Signal control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal control method in the case of a collision of signals generated between layers and a signal passing each other in a communication system configuration in which communication functions are hierarchized.

[0002]

2. Description of the Related Art FIG. 3 shows a configuration example of a conventional communication system in which communication functions are hierarchized.

[0003] The main concept of Fig. 3 is the layering of communication functions.

[0004] Functions such as error control and data format are divided into several levels based on the shape of the connector and the signal level, and the layers are hierarchized, so that unified management of resources between nodes and cooperation between services are achieved. Is achieved.

[0005] In full-duplex communication in a communication system configuration in which communication functions are hierarchized, signal collision and signal passing occur between layers.

[0006] One example of the problem is described in CCITT Recommendation X. 2
An example of the five communication control devices will be described focusing on layer 2.

[0007] Problems seen from the sequence

FIG. 4 shows a signal collision / signal passing sequence.

In FIG. 4, SABM (Set Asynchronous Bal)
anced Mode) activates link setting by asynchronous balanced mode setting command, UA (Unnumbered Acknowledge) is response to SABM and DM with unnumbered confirmation response, RR
(Receive Ready) indicates the frame receivable state by the receivable command / response (non-congestion), LCW (LinkCo
mmand Word) = CCW (Channel Command Word) is a link command word (channel command word), which is a command word for instructing the input / output device specific input / output operations, LSW
(Link Status Word) = CSW (Channel Status Word)
) Are link state words (channel state words), LSW, C
SW is a status word for notifying the status of the input / output operation.

When establishing a link connection with a communication partner module, a link connection setting request issued from an upper layer of the own module [FIG. & 2]
Link connection arrival notification asynchronously notified from the communication partner module with [Figure 4. & 1] [Fig. *
2]-Passing [Fig. & 2, & 3], the link connection setting request issued from the upper layer of the own module ends in error [FIG. & 5] is returned to the upper layer of the request issuing source [FIG. & 6].

Thereafter, an RR issuance request is issued again from the upper layer [FIG. & 6, & 7].

[0012] Problems seen from state transition diagrams

FIG. 5 shows part of a state transition diagram of layer 2 of the communication system configuration of the own module.

Idle state after completion of initialization [FIG. *
1] Asynchronous link connection notification from lower layer [Fig. & 1], the incoming connection is in progress [FIG.
* 2], a link connection setting request from an upper layer [FIG. & 2] is returned to the request issuer as an error termination of state mismatch.

Thereafter, the upper layer sends a link connection incoming response [FIG. & 7] and data transfer is possible [FIG. * 3].

[0016]

Conventionally, in this type of communication system configuration in which communication functions are hierarchized, there is a problem seen from the above-mentioned sequence and a problem seen in a state transition diagram.

An object of the present invention is to solve the conventional problems,
It is an object of the present invention to provide a signal control method for reducing a processing load generated when a signal collision or a signal passing occurs, and for quickly establishing a data transfer enabled state.

[0018]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for controlling signal collision and signal passing occurring between layers in a communication procedure between communication systems having hierarchical communication functions. In the method, when a collision occurs between a link connection setting request from an upper layer and a link connection arrival notification signal from a lower layer, a system call of an RR transmission request is issued to the lower layer from the layer where the collision occurred, and the upper layer When a signal passing occurs between the link connection setting request from the host and the event notification from the layer, the upper layer normally terminates the link connection setting request processing in the upper layer of the request issuing source with the event. Features.

[0019]

When a collision occurs between a link connection setting request from an upper layer and a link connection arrival notification signal from a lower layer, a system call for an RR transmission request is issued to the lower layer from the layer where the collision occurred.

When a signal passes between the link connection setting request from the upper layer and the notification of the event (link connection arrival) from the layer, the upper layer sends the event (corresponding to the link connection arrival notification) to the request. The processing is normally terminated in the upper layer of the request issuing source.

By improving these two points, it is possible to greatly reduce the processing required when a signal collision or a signal passing occurs.

In particular, it is effective for a layer in which a plurality of link connections can be set, and can quickly establish a data transferable state.

[0023]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
As an example, CC. The following description focuses on layer 2 of the 25 communication control device.

[0024] Examples of countermeasures seen in sequence diagrams

FIG. 1 shows a collision / signal passing sequence of signals to which the present invention is applied.

A link connection setting request from an upper layer [FIG. & 2] is a link connection incoming notification from a lower layer [FIG. & 1] after receiving the state transition [Fig. * 2] When it is determined that the arrival has arrived,
The system call of the issue request (data reception start) is generated from the layer in which the collision has occurred [FIG. P1 → P
2].

A link connection setting request from an upper layer [FIG. & 2], and notification of an event (link connection arrival) from the layer [FIG. & 3], when the signals pass each other, the upper layer normally terminates the request processing in the upper layer of the request issuer with the event (corresponding to the notification of the arrival of the link connection) [FIG. & 4].

The conventional processing sequence [FIG. & 5, & 6, & 7] can be omitted.

[0029] Example of countermeasures seen in the state transition diagram

FIG. 2 shows a part of a state transition diagram to which the present invention is applied.

Incoming connection state [FIG. * 2],
Data transfer enabled state [Fig. * 3] is a conventional link connection incoming response [Fig. & 7] or reception of a link connection setting request from an upper layer [FIG. & 7].

[0032]

As described above, according to the present invention, 1) the processing load on the upper layer can be reduced (set a plurality of link connections) as compared with the conventional communication system in the case of collision of signals and passing of signals. (Especially effective for possible layers.) 2) Since a data transfer enabled state can be quickly established, highly real-time processing of the communication system can be realized.

[Brief description of the drawings]

FIG. 1 is a signal collision / signal passing sequence after countermeasures to which the present invention is applied.

FIG. 2 is a part of a state transition diagram after a measure to which the present invention is applied.

FIG. 3 is a configuration example of a communication system in which communication functions are hierarchized.

FIG. 4 is a signal collision / signal passing sequence before a measure is taken;

FIG. 5 is a part of a state transition diagram before a measure is taken;

[Explanation of symbols]

 UA Unnumbered confirmation response RR Receivable command / response LCW Link command word LSW Link status word

Claims (1)

(57) [Claims] The present invention relates to a communication procedure between communication systems in which communication functions are hierarchized.
In the signal control method for passing signals, when a collision occurs between a link connection setting request from an upper layer and a link connection arrival notification signal from a lower layer, a system call of a receivable command / response (RR) transmission request is issued to the lower layer. Is issued from the layer in which the collision occurs, and when a signal passes by a link connection setting request from an upper layer and an event notification from the layer, the upper layer carries out the link connection setting request processing with the event. Is normally terminated in the upper layer of the request issuing source.