JPH0746291A - Link reset method - Google Patents

Abstract

PURPOSE:To apply two-way reset service to the user by starting sequentially a unidirection reset of an SSCOP in both ways by a 2-way reset request from the user so as to realize the link set in both the directions. CONSTITUTION:The method employs 1st and 2nd user terminal equipments 10, 20, an SSCOP link 30 and protocol data units PDU 40, 41. Then the users 1, 2 use the link 30 to make two-way communication. A 1st unidirectional reset is started in the direction of the other user 2 by the request from the user 1. Then the 2nd unidirectional reset is started in the direction of the user 1 after the start in the 1st unidirectional reset before the end of the 1st unidirectional reset. The user 1 informs it that 2-way reset is started to the user 2 after the end of 2nd unidirectional reset and when the user 2 requests the consecution of the two way reset, the 1st unidirectinal reset is finished and the user 2 informs it to the user 1 that the 2-way reset is finished.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a link reset method, and more particularly, to a ITU-T (International Telecommunication Union) Recommendation Draft Q. SALL "Service Specific Connection Oriented Protocol
l: SSCOP) ”or the like and relates to a link reset method in a link that transfers information by SSCOP.

[0002]

2. Description of the Related Art There is an ATM which transfers information between user terminals by a cell of a fixed length packet in an asynchronous transfer mode (hereinafter referred to as ATM). In order to transfer the call control information and user data on this ATM network, the information is numbered data (Sequence).
It has been agreed that ITU-TS recommends SSCOP, which is characterized by transferring in variable length frames called enced data (SD), and is used for call control signal transfer.

Further, it is considered to use this SSCOP also when data is transferred on the ATM network.

Conventionally, ITU-T Recommendation Q. 811 “lower layer protocol file for Q3 interface”, etc., is ISO standard ISO8 for transfer of network management information and the like.
Connection Oriented Network layer Service (C)
ONS) and the connection standard transport layer service (Connection Oriente) defined by ISO standard ISO8073.
A protocol profile using d Transport layer Service (COTS) has been standardized, and it is expected that provision of CONS or COTS on the ATM network will be required for transfer of network management information of the ATM network in the future. Also,
ISO standard 8571 "file transfer, for file transfer,
Access and Manage "(File Transfer, Access and Manage
ment: FTAM) and other applications such as FTAM are also defined to use CONS and COTS, and C is also used for transferring user data on the ATM network.
Provision of ONS and COTS is required.

The CONS and COTS provide a bidirectional reset service for resetting the link in both directions at the same time, and it is necessary to provide the bidirectional reset service on the SSCOP using the ATM network for the above purpose. .

[0006]

However, the above S
Since the SCOP does not provide the bidirectional service, it is necessary to provide the bidirectional reset service to the user by some method in order to realize the bidirectional reset service as described above using the SSCOP.

ITU-T Recommendation Q. Q.922 defined in “ISDN Data Link Layer Specification for Frame Mode Bearer Service” and the like. The 922 procedure does not provide the bidirectional lit service to the user.

This Q. ITU-T Recommendation Q.922 so that users located above 922 can use CONS. 922
Appendix IV “Convergence Protocol for Providing OSI-CONS over Q.922” is recommended. With this rule, the user can be presented with a two-way reset service. The 922 link itself is not reset and does not provide a two way reset service in the full sense.

Further, since the SSCOP does not provide the bidirectional service, in order to realize the bidirectional reset service as described above using the SSCOP, the bidirectional reset service is provided to the user while using the SSCOP other than the bidirectional reset service. It is necessary to provide.

The present invention has been made in view of the above points, and solves the above-mentioned conventional problems, and when two users communicate using a two-way communication link, there is a two-way reset request from the user. In this case, it is an object of the present invention to provide a link reset method that can realize a bidirectional link reset.

[0011]

FIG. 1 is a diagram for explaining the principle of the present invention. The present invention relates to a case where two users communicate using a two-way communication link including a one-way reset method for performing one-way link reset,
At the request of the first user, the first one-way reset in the direction to the other second user is activated (step 1), and after the activation of the first one-way, both directions are given to the second user. Notifying that the reset has been started (step 2), and when the second user requests the continuation of the two-way reset, activates the second one-way reset 2 oriented to the first user (step 3), After activating the second one-way reset, the first user is notified that the two-way reset is complete (step 4).

FIG. 2 is a diagram for explaining the principle of the present invention. The present invention, when two users communicate by using a two-way communication link having a one-way reset method for performing a one-way link reset, requests a second user to another second user when a request is made from the first user. Activating a first one-way reset of the orientation (step 11), and after activating the first one-way reset and before the completion of the first one-way reset, a second orientation of the first user. The direction reset is activated (step 12), and after the second one-way reset is completed, the second user is notified that the two-way reset has started (step 13), and the second user is notified of the two-way reset. When the continuation is requested, the first one-way reset 1 is completed (step 14), and the first user is notified that the two-way reset is completed (step 1).
5).

[0013]

According to the present invention, when two users communicate by using a two-way link of SSCOP which has a one-way reset method but does not have a two-way reset method, the SSCO
When two users communicate by using the P bidirectional communication link, one reset of SSCOP is sequentially activated in both directions in response to a bidirectional reset request from the users to realize a bidirectional link reset, and the bidirectional reset is performed for the user. Provide services.

[0014]

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

FIG. 3 shows an outline of the present invention. The system configuration shown in the figure has the first and second user terminals 10 and 2.
0, SSCOP (using service-dependent connection type protocol) link 30, and protocol data units (hereinafter, PDU) 40 and 41. In the figure, it is assumed that two user terminals 1 and 2 perform bidirectional communication using the SSCOP link 30.

FIG. 4 shows an example of the sequence of the unidirectional link reset service of the SSCOP link of the present invention.

Step 100) User 1 sends an AA-RESSYNC request, which is a one-way reset request, to SSCOP entity 1.

Step 101) User 1 to AA-RE
Upon receiving the SYNC request, the SSCOP entity 1
The RS (Resynchronization) PDU is transmitted to the other SSCOP entity 2 and the transmission reset process is performed. This transmission reset processing consists of clearing the transmission buffer and resetting the state variables for transmission.

Step 102) S receiving RSPDU
The SCOP entity 2 issues the AA-RESSYNC instruction notifying the user 2 that the one-way reset has been performed, and also performs the reception reset process. This reception reset processing consists of clearing the reception buffer and resetting the reception state variable.

Q. SAAL1 further defines the exchange of PDUs in the opposite direction to notify confirmation of the one-way reset, but generally, the sequence shown in FIG. 4 can realize the one-way link reset.

FIG. The sequence of the one-way link reset service defined by SAAL1 is shown.

Step 200) The user 1 sends to the SSCOP entity 1 an AA-RESSYNC request which is a one-way reset request.

Step 201) AA-RE from user 1
Upon receiving the SYNC request, the SSCOP entity 1
The RSPDU is transmitted to the partner SSCOP entity 2 and transmission reset processing is performed.

Step 202) SSC receiving PDU
The OP entity 2 issues the AA-RESSYNC instruction notifying the user 2 that the one-way reset has been performed, and also performs the reception reset process.

Step 203) User 2 has SSCOP
A for confirming occurrence of one-way reset to entity 2
Make an A-RESSYNC response.

Step 204) AA-R from user 2
Upon receiving the ESYNC, the SSCOP entity 2 receives the S
The RSAK PDU is transmitted to the SCOP entity 1.

Step 205) When the SSCOP entity 1 receives the RSAK PDU, it sends an AA-RESSYNC confirmation for notifying the user 1 of the completion of the one-way reset.

Thus, in the figure, in addition to the sequence of FIG. 4, the SSCOP entity 2 sends an SAKOP entity 1 RSAK to the SSCOP entity 1 in response to the AA-RESYNC response from the user 2 for confirming the occurrence of the one-way reset.
(Resynchronization Acknowledgment) PDU is transmitted, and the SSCOP entity 1 that has received this RSAK PDU issues AA-RESSYNC confirmation notifying the requesting user 1 of the completion of the one-way reset.

FIG. 6 shows the sequence of the bidirectional reset service as seen from the user. When the user 1 issues an AAL-RESET request, which is a two-way reset service request, an AAL-RESET instruction is issued to notify the user 2 that the two-way reset service has started. In response to this, the user 2 issues an AAL-RESET response permitting the continuation of the two-way reset service.

After that, when the transmission reset processing and the reception reset processing are completed on both sides of the link, the AAL-REST confirmation notifying the completion of the bidirectional reset service is issued to the user 1.

An example of the reset service will be shown below. (First Embodiment) FIG. 7 shows a method for providing a two-way reset service according to a first embodiment of the present invention. The figure shows a method of providing the bidirectional reset service as shown in FIG. 6 by using the unidirectional reset service sequence shown in FIG.

Step 300) When the user 1 has an ALL-RESET request which is a two-way reset service request, the terminal of the user 1 sends an AAL-RESSYNC request which is a two-way reset service request to the SSCOP entity 1.

Step 301) ALL-R from user 1
SSCOP entity 1 that received the ESYNC request
Performs the transmission reset process and simultaneously transmits the RSPDU.

Step 302) S receiving RSPDU
The SCOP entity 2 issues the AA-RESSYNC instruction to the user 2 simultaneously with the reception reset process.

Step 303) User 2 uses AA-RE
Based on the SYNC instruction, the AAL-RESET instruction, which is the instruction for the two-way reset service, will be issued.

Step 304) The user 2 who confirms the start of the bidirectional link reset issues an AAL-RESET response.

Step 305) User 2 selects SSCOP
It issues an AA-RESSYNC request, which is a reverse unidirectional link reset request, to entity 2.

Step 306) User 2 receives AA-RE
Upon receiving the SYNC request, the SSCOP entity 2
The RSPDU is issued to the SSCOP entity 1 and transmission reset processing is performed.

Step 307) S receiving RSPDU
The SCOP entity 1 issues the AA-RESINC instruction at the same time as the reception reset processing is performed, and this is used as a trigger to notify the user of the completion of the bidirectional link reset A
Issue an AL-RESET confirmation.

By this method, the unidirectional link reset service provided in the sequence of FIG. 4 is combined,
The user 1 and the user 2 can be provided with the bidirectional link reset service as shown in FIG.

Even if the one-way link reset service provided in the sequence shown in FIG. 5 is used, the two-way link reset service can be provided by the same method. FIG. 8 shows a sequence for explaining another example of the first embodiment of the present invention. In this case, as shown in FIG. 8, after the SSCOP entity 2 issues the AA-RESSYNC instruction, the SSCOP entity 2 sends the AA-R
Receives ESYNC response and responds with RSAK PDU
Is sent to SSCOP entity 1. Upon receiving this RSAK PDU, SSCOP entity 1 issues an AA-RESSYNC confirmation.

Further, the SSCOP entity 1 is AA
-After issuing the RESYNC instruction, AA-RESSYNC
It receives the response and sends a RSAK PDU towards the SSCOP entity 2. The SSCOP entity 2 receiving this RSAK PDU issues an AA-RESSYNC confirmation.

(Second Embodiment) A second embodiment will be described below.

FIG. 9 shows a method for providing a two-way reset service according to the second embodiment of the present invention. The figure is a sequence diagram when the unidirectional link reset service shown in FIG. 5 is used to provide the bidirectional link reset service as shown in FIG.

Step 400) When the AAL-RESET request, which is a two-way reset service request, is received from the user 1, the terminal of the user 1 makes the terminal of the SSCOP entity 1
Issue an AA-RESSYNC request to the.

Step 401) The SSCOP entity 1, which has received the AA-RESSYNC request, performs the transmission reset process and at the same time transmits the RSPDU.

Step 402) S receiving RSPDU
The SCOP entity 2 issues the AA-RESSYNC instruction to the user 2 at the same time as performing the reception reset process.

Step 403) Based on this, User 2 immediately informs SSCOP Entity 2 of AA-
Issue a RESYNC request.

(Step 404) This AA-RESSYNC
Upon receiving the request, the SSCOP entity 2 performs a transmission link reset process and at the same time sends an RS to the SS entity 1.
Send the PDU.

Step 405) S receiving RSPDU
The SCOP entity 1 issues the AA-RESSYNC instruction to the user 1 at the same time as performing the reception reset process.

Step 406) This AA-RESSYNC
In response to the instruction, user 1 issues an AA-RESSYNC response to SSCOP entity 1.

Step 407) In response, SSCOP
Entity 1 sends the RSAK PDU towards SSCOP Entity 2.

Step 408) The SSCOP entity 2 receiving this RSAK PDU gives the user 2 an AA-R.
Send ESYNC confirmation.

Step 409) The user 2 issues an AAL-RESET instruction which is an instruction for the bidirectional reset service.

Step 410) When the user 2 who confirms the start of the two-way link reset issues the AAL-RESET response, it is the confirmation of the first requested one-way link reset request to the SSCOP entity 2 AA.
Issue a RESYNC response.

Step 411) SSCO which received this
The P entity 2 sends the RSAK PDU to the SSCOP entity 1.

Step 412) The SSCOP entity 1 which has received the RSAK PDU issues an AA-RESSYNC confirmation, which is triggered by the issuance of an AAL-RESET confirmation notifying the user 1 of the completion of the bidirectional link reset.

By this method, the unidirectional link reset service provided by SSCOP can be combined to provide the bidirectional link reset service as shown in FIG. 6 to user 1 and user 2.

[0059]

As described above, according to the present invention, when two users communicate using a bidirectional communication link, the SSCO is issued by a bidirectional reset request from the users.
The bidirectional reset service can be provided to the user by sequentially activating the unidirectional reset of P in both directions to realize the bidirectional link reset.

[Brief description of drawings]

FIG. 1 is a diagram (No. 1) for explaining the principle of the present invention.

FIG. 2 is a diagram (part 2) for explaining the principle of the present invention.

FIG. 3 is a diagram showing an outline of the present invention.

FIG. 4 is a diagram showing an example of a sequence of a unidirectional link reset service of an SSCOP link.

FIG. 5: Q. It is a figure which shows the sequence of the one-way link reset service defined by SAAL1.

FIG. 6 is a diagram showing a sequence of a two-way reset service viewed from a user.

FIG. 7 is a diagram illustrating a method for providing a two-way reset service according to the first embodiment of the present invention.

FIG. 8 is a diagram showing another example of the first embodiment of the present invention.

FIG. 9 is a diagram showing a sequence of a method for providing a two-way reset service according to a second embodiment of the present invention.

[Explanation of symbols]

 10 first user terminal 20 second user terminal 30 SSCOP link 40, 41 protocol data unit (PDU)

Claims (2)

[Claims] 1. When two users communicate using a two-way communication link having a one-way reset method for performing a one-way link reset, a request from the first user causes a request to the other second user. Activating the first one-way reset, and after the first one-way activation, notifies the second user that the two-way reset has started, and the second user notifies the two-way When the reset is requested to continue, the second one-way reset 2 directed to the first user 2
And activating the second one-way reset, and then notifying the first user that the two-way reset is completed. 2. When two users communicate using a two-way communication link having a one-way reset method for performing one-way link reset, a request from the first user causes a request to the other second user. A first one-way reset for the first orientation, and a second piece of orientation for the first user after activation of the first one-way reset and before completion of the first one-way reset. Activating a directional reset, notifying the second user that a two-way reset has been initiated after the completion of the second one-way reset, and the second user requesting that the two-way reset be continued. A link reset method comprising: completing a first one-way reset 1 and notifying the first user that the two-way reset is completed.