JPH0964881A - Method and device for confirming multi-cast connection state - Google Patents

Abstract

PROBLEM TO BE SOLVED: To confirm a connection state such as interruption in the case of conducting multicast fixed connection communication. SOLUTION: Upon receipt of a state confirmation request message sent by a terminal equipment 21, when the message is a state confirmation request message valid for protocol, a communication controller 41 makes an information collection request to a multicast server 51. As a result of the information collection request, reply information of a state of line containers 71-7n collected and arranged by the multicast server 51 is returned from the multicast server 51 to the communication controller 41 then the communication controller 41 edits a connection state notice message, based on the reply information and sends the result to the multicast server 51 to be returned to the terminal equipment 21 via a line container 62.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-speed packet communication system such as a frame relay and a cell relay that divides communication data into segments and relay-transfers them in a network. The present invention relates to a multicast connection state confirmation method and apparatus for confirming a connection state of a fixed connection in a multicast service such as broadcast communication or multiple-to-multiple broadcast communication.

[0002]

2. Description of the Related Art The following two systems are known as high-speed packet communication systems for dividing communication data into segments and relay-transferring them in a network.

(1) Frame Relay A frame relay is a relay-type packet-type communication system intended for data link layer frames, and is a system for relaying data at the data link layer frame level for communication. .

(2) Cell relay The cell relay is an ATM (Asynchronous Transfer Mode).
Known as an exchange system, it is a relay-type packet-type communication system for physical layer cells, and is a system for relaying data at the cell level of the physical layer for communication.

These high-speed packet communication systems using frame relay and cell relay (that is, ATM) are already known as high-speed / broadband communication technologies.

Frame relay and cell relay (AT
M) is a new technology, and is currently a multicast service such as one-to-many or 1-n (1: n) broadcast or multiple-to-many or n-n (n: n) broadcast. Has not been realized. In the standardization work such as the international recommendation of the communication system using the frame relay and the cell relay (ATM), only the implementation method for the multicast type communication is specified.

On the other hand, as one form of service in the data communication system, there is a fixed connection service in which a connection is fixedly set in advance and communication is performed in the set connection. A typical example of such a fixed connection service is a PVC (permanent vertual connec).
tion). In addition, fixed connection service,
SPC (semi-permanent v) having an incoming call notification procedure in ISDN (integrated services digital network)
There is also a semi-fixed connection service called "irtual connection", but this is also a kind of fixed connection service. In this specification, if simply "fixed connection" is used, this SP
A service form such as C is also included.

[0008]

In the relay type network service such as the frame relay and the cell relay described above, the PVC state confirmation system is indispensable when performing fixed connection communication such as PVC communication.
This is also the case when performing multicast type fixed connection broadcast communication, for example, multicast PVC broadcast communication.

If such a state confirmation system is not provided, it is impossible to know the state of fixed connection such as disconnection of connection. However, in the PVC status confirmation procedure stipulated in existing international recommendations, etc.,
Although there are two procedures, "status notification for one PVC" and "status notification for all PVCs under contract", no PVC status confirmation procedure for the multicast service is specified.

The present invention has been made to solve such a problem, and in a relay type network service such as a frame relay and a cell relay, to confirm a connection state when performing multicast fixed connection communication. It is an object of the present invention to provide a multicast connection status confirmation method and device.

[0011]

A first method for checking a multicast connection state according to the present invention comprises at least a fixed link connection on a high-speed packet communication system in which communication data is segmented and relay-transferred in a network. In the case of a multicast service where one side has multiple broadcasts, define a connection status notification message that lists the status information of all the destination link connections under the multicast, and use it to check the connection status for each multicast link connection. [Claim 1]

The high-speed packet communication system may be a frame relay network system [claim 2] or a cell relay network system [claim 3].

The connection status confirmation by the connection status notification message for each multicast link connection may be applied to the link connection of the user network interface [Claim 4] or the link connection of the inter-network interface. [Claim 5] may be applied to an interworking function between the frame relay network and the cell relay network [Claim 6].

The link connection by the fixed connection may include a link connection by the semi-fixed connection [claim 7]. A second multicast connection state confirmation method according to the present invention is a high-speed packet communication system in which communication data is segmented and relay-transferred in a network, and broadcast communication in which at least one of fixed link connection is plural. In the multicast service to be performed, define a connection status notification message that contains status information that activates the status only when all the destination link connections under the multicast are active, and use it to confirm the connection status of the multicast link connection. [Claim 8]

The high-speed packet communication system may be a frame relay network system [claim 9] or a cell relay network system [claim 10].

The connection state confirmation by the connection state notification message of the multicast link connection may be applied to the link connection of the user network interface [Claim 11] or the link connection of the inter-network interface [Claim 11]. The invention may be applied to an interworking function between the frame relay network and the cell relay network [claim 13].

The fixed connection link connection may include a semi-fixed connection link connection. A third multicast connection state confirmation method according to the present invention is a high-speed packet communication system in which communication data is segment-divided and relay-transferred in a network, in which broadcast communication in which at least one of fixed link connections is plural is performed. In performing the multicast service, one or more important destination connections among the destination link connections under the multicast are registered in advance when the multicast contract is registered,
By defining a connection status notification message containing status information that activates the status only when all of the one or more important partner connections among the partner link connections under the multicast are active, It is characterized in that it is used for confirmation of the connection state [claim 15].

The high-speed packet communication system may be a frame relay network system [claim 16] or a cell relay network system [claim 17].

The connection status confirmation by the connection status notification message of the multicast link connection may be applied to the link connection of the user network interface [Claim 18] or the link connection of the inter-network interface. The invention may be applied to an interworking function between the frame relay network and the cell relay network [claim 20].

The fixed connection link connection may include a semi-fixed connection link connection. A first multicast connection state confirmation device according to the present invention is a multicast that performs broadcast communication in which at least one of fixed link connection is plural by high-speed packet communication in which communication data is segmented and relay-transferred in a network. A multicast connection status confirmation device in a high-speed packet communication system that provides services including services,
In response to the connection status confirmation request message, status collecting means for collecting the status information of all the destination link connections under the multicast, and the status of all the destination link connections under the multicast based on the collection result by the status collecting means. Message editing means for editing a connection status notification message in which information is listed, and the connection status confirmation request message is received from the connection status confirmation requesting connection and given to the status collecting means, and edited by the message editing means. And a transfer control means for returning a connection status notification message to the connection status confirmation requesting connection [claim 22].

The high-speed packet communication system may be a frame relay network system [claim 23] or a cell relay network system [claim 24].

The link connection may be a user network interface link connection [claim 25] or an inter-network interface link connection [claim 26], and may be a frame relay network and a cell relay network. It may be a link connection by an interworking function between [claim 27].

The fixed connection link connection may include a semi-fixed connection link connection. A second multicast connection status confirmation device according to the present invention is a multicast performing high-speed packet communication in which communication data is segmented and relay-transferred in a network, thereby performing broadcast communication in which at least one of fixed link connections is plural. A multicast connection status confirmation device in a high-speed packet communication system that provides services including services,
In response to the connection status confirmation request message, status collecting means for collecting the status information of all the destination link connections under the multicast, and based on the collection result by the status collecting means, all the destination link connections under the multicast are active. And a message editing means for editing a connection status notification message including status information that activates the status, and receiving the connection status confirmation request message from the connection status confirmation requesting connection and giving it to the status collecting means. And a transfer control means for returning the connection state notification message edited by the message editing means to the connection state confirmation requesting connection [claim 2]
9].

The high-speed packet communication system may be a frame relay network system [claim 30] or a cell relay network system [claim 31].

The link connection may be a user network interface link connection [claim 32] or an inter-network interface link connection [claim 33], and may be a frame relay network and a cell relay network. It may be a link connection by an interworking function between [claim 34].

The fixed connection link connection may include a semi-fixed connection link connection. A third multicast connection status confirmation apparatus according to the present invention performs multicast communication in which at least one of fixed link connection is plural by high-speed packet communication in which communication data is segmented and relay-transferred in a network. A multicast connection status confirmation device in a high-speed packet communication system that provides services including services,
Important destination registration means for pre-registering one or more important destination connections among the destination link connections under the multicast, and the state of all destination link connections under the multicast in response to the connection status confirmation request message. Only when all of the registered one or more important destination link connections among the destination link connections under the multicast are active based on the state collection means for collecting information and the collection result by the state collection means. Message editing means for editing a connection status notification message including status information for activating a status; and a message editing means for receiving the connection status confirmation request message from a connection status confirmation requesting connection and giving it to the status collecting means. The connection status notification message edited in Sage, is characterized by comprising a transfer control means for returning to the connection status confirmation requesting connection [Claim 36].

The high-speed packet communication system may be a frame relay network system [claim 37] or a cell relay network system [claim 38].

The link connection may be a user network interface link connection [claim 39] or an inter-network interface link connection [claim 40], and may be a frame relay network and a cell relay network. It may be a link connection by an interworking function between [claim 41].

The fixed connection link connection may include a semi-fixed connection link connection.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a multicast connection status confirmation system according to the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 shows the configuration of a first embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention.

The exchange system of FIG. 1 has an exchange 10 and terminals 21 and 31, 32 ... 3n. Terminal 2
1 has contracted a multicast PVC with the terminals 31 to 3n and registered it in the system. In this case, the terminal 21 is the calling terminal and the terminals 31 to 3
n is the destination terminal.

The exchange 10 includes a communication control device 41, a multicast server 51, line accommodation devices 61, 62, ...
N and 71, 72 ... 7n. Exchange 10
2 corresponds to the frame relay network itself in the case of the frame relay system as shown in FIG. 2, and is applied to a user network interface (user to network interface: hereinafter, referred to as “UNI”) of the frame relay network. The case will be described. In this case, the UNI may be synchronous / asynchronous.

The line accommodating devices 61 to 6N are accommodating devices for accommodating lines connected to the incoming or outgoing subscriber terminals, but in this case, only the terminal 21 is considered as the outgoing subscriber terminal. Therefore, in FIG. 1, only the line accommodation device 62 is shown as being connected to the terminal 21.

The line accommodating devices 71 to 7n are line accommodating devices for accommodating lines connected to outgoing side or incoming side subscriber terminals. In this case, the terminals 31 to 3n are considered as incoming side subscriber terminals. Therefore, in FIG. 1, the line accommodation devices 71 to 7n are shown as being connected to the terminals 31 to 3n.

The multicast server 51 stores the multicast condition according to the registered content of the multicast PVC between the terminal 21 and the terminals 31 to 3n. The multicast server 51 transfers the data received from the terminal 21 via the line accommodation device 62 to the communication control device 41,
The data sent from the communication control device 41 is transferred to the terminal 21 via the line accommodation device 62.

Further, during normal data communication, the multicast server 51 uses the data provided from the communication control device 41 for the terminals 31 to 3n according to the multicast condition.
The same data is simultaneously transmitted via the line accommodation devices 71 to 7n. When checking the PVC status, the multicast server 51 determines from the stored multicast condition that
The target destination terminal is selected, the state confirmation is performed on the line accommodation devices 71 to 7n accommodating the corresponding terminals 31 to 3n, and the state of each line accommodation device 71 to 7n is collected, The information is collected and a response is returned to the communication control device 41.

During normal data communication, the communication control device 41 performs protocol processing necessary for data communication on the data transmitted from the terminal 21 and transferred from the multicast server 51, and then transmits the data to the terminals 31 to 3n. To the multicast server 51.

Also, when the communication control device 41 receives the PVC status confirmation request message (hereinafter, referred to as “SE message”) transmitted by the terminal 21, at the time of confirming the PVC status, the SE message is transmitted as a protocol. Message determination processing such as determination as to whether it is valid according to the regulations is performed, and if it is determined that the SE message is valid, a request for information collection is made to the multicast server 51. As a result of this information collection request, each line accommodation device 7 collected and collected by the multicast server 51
The response information in the state of 1 to 7n is the multicast server 5
1 to the communication control device 41, the communication control device 4
1 is a PVC status notification message (PVC status message: a connection status notification message based on the response information).
Hereinafter, the “S message” will be edited and sent to the multicast server 51 to be returned to the terminal 21 via the line accommodation device 62.

There are various variations in editing the S message in the communication control device 41. In the case of this embodiment, the communication control device 41 uses the line accommodation devices 71 to 7n.
From the terminal 3 via the multicast server 51
The S message in the form of listing the state information of 1 to 3n is edited.

Next, the exchange system shown in FIG. 1 will be described in more detail with reference to FIGS. First,
A sequence in the case of normal normal data communication on the UNI will be described.

(1) The terminal 21 contracts with the terminals 31 to 3n for a multicast PVC, and this contract is registered in the system, and in this case, the multicast server 51 of the exchange 10 which is a frame relay network. ,
The multicast conditions based on the contract content are stored.

(2) When the terminal 21 transmits data, the corresponding line accommodation device 62 in the exchange 10 receives the data and transfers the data to the communication control device 41 via the multicast server 51. At this time, the multicast server 51 does not perform any special processing and simply transfers the data.

(3) The communication control device 41 performs protocol processing required for normal data communication on the received data, and transfers the resulting data to the multicast server 51 on the output side.

(4) The multicast server 51 broadcasts the same data to the corresponding terminals 31 to 3n according to the stored multicast conditions. Next, a multicast PVC status confirmation sequence on the UNI will be described. FIG. 3 schematically shows a multicast PVC status confirmation sequence on the UNI.

(1) When the terminal 21 sends a multicast PVC status confirmation request message, that is, a multicast SE message, the corresponding line accommodation device 62 in the exchange 10 receives the SE message and controls communication via the multicast server 51. Transfer the SE message data to the device 41. At this time, the multicast server 5
1 does not perform any special processing on the received data and simply SE
It just transfers the message to the communication controller 41.

(2) The communication control device 41 performs a judgment process on the received message as to whether or not the received message is valid according to the protocol definition, and when it is judged that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) Based on the stored multicast conditions, the multicast server 51 uses the multicast P
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected, and the state confirmation is performed on the line accommodation devices 71 to 7n that accommodate the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51 which has confirmed the state of each line accommodation device 71 to 7n and collected information is
The collected information is collected and a response is returned to the communication control device 41.

(5) The communication control device 41 edits the multicast PVC status notification message, that is, the multicast S message, based on the response information returned from the multicast server 51, and the terminal via the multicast server 51 and the line accommodation device 62. Return to 21.

In this case, the multicast S message is, as shown in the concept of FIG. 4, for each PVC # 1, PVC # 2 ... PVC of the multicast PVC set for one data link from the terminal to the exchange 10. It is edited so as to include state information listing the states for #n.

Examples of specific formats of the SE message and the S message that can be used in the frame relay system described above are shown in FIGS. 5 and 6 are CCITT (International Telecommunication Telephone Advisory Committee), which is the standard specification of the frame relay system, that is, ITU-T (International Telecommunication Un
Ion-Telecommunications Sector) Q. 93
TTC (Telegraph and Telephone Commission: The) that complies with Annex A of 3
Telecommunication Technplogy Committee) Standard JT
-Q. The formats of the SE message and S message for checking the multicast PVC status corresponding to the format shown in Appendix A of 933 are shown.

FIG. 5 is a format that defines information about the report type indicating the SE message. In this case, in the first byte (first octet), the bit number 8 is “0” and the bit numbers 7-1 are the information element identifiers,
In this case, "101000", which indicates that the information is the report type
The second byte indicates the information element length, that is, the content length of the report type. In this case, since it is 3 bytes (3 octets) as a whole, it is “000000011”. The 3 bytes are information indicating the report type. In this case, in order to indicate the status confirmation (request) of the multicast PVC, for example, “00000011” which is not defined in the above standard is used.

FIG. 6 is a format for defining the information regarding the information element identification indicating the S message and the multicast PVC status confirmation information. In this case, in the first byte (first octet), the bit number 8 is “0” and the bit numbers 7 to 1 are the information element identifiers, and in this case, “101111” indicates that it is the information of the multicast PVC state.
1 ". The second byte indicates the information element length, that is, the content length of the multicast PVC state, and in this case depends on the number of PVCs in the multicast. And the third byte and below are information indicating the multicast PVC state. In this case, each PVC consists of 3 bytes (3 octets), which is 3 × (number of PVC) bytes.

The bit number 8 of the first 1 byte of each 3 bytes is "0" which means an address extension octet,
The bit number 8 of the second 1 byte is "1" which means an address extension octet, and the bit number 8 of the third 1 byte is "1" which means an address extension octet.
The first 1-byte bit numbers 6 to 1 are the upper 6 bits of the data link connection identifier indicating the multicast PVC identifier, and the second 1-byte bit numbers 7 to 4 are data indicating the multicast PVC identifier. It is assumed that there are 4 bits following the upper 6 bits (bit numbers 6 to 1) of the first 1 byte of the link connection identifier. The bit number 4 of the third byte is a new bit N which indicates whether it is new, and the bit number 2 is an active bit A which indicates whether it is active. When the new bit N is "0", it means that it has already been given, and when it is "1", it means that it is new. When the active bit A is "0", it means inactive, and when it is "1", it means active.

Others are all (bit number 7 of the first 1 byte, bit number 3 of the second 1 byte).
1) Bit number 7 to 5 of the third byte, bit number 3 and bit number 1) Reserved bit, and in this case, it is set to "0". As described above, from the bit number 6 of the first 1 byte to the bit number 4 of the second 1 byte (that is, the bit numbers 6 to 1 of the first 1 byte).
And the second 1-byte bit numbers 7 to 4) are the identification numbers assigned to each multicast PVC in advance. This identification number is the terminal-
It is assigned between networks or between networks.

In this way, in the UNI network service by frame relay, in the case of performing multicast fixed connection communication, a connection state notification message in which the state information of the destination link connection under the multicast is edited is defined, By transferring it, it is possible to confirm the connection state such as disconnection of the multicast destination link connection.

Particularly in this case, as the S message,
Since the connection status notification message that enumerates all the status information of the partner link connections under the multicast is used, it is possible to specifically know the individual status of the partner link connections under the multicast.

[Second Embodiment] A second embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is a switching system having a configuration similar to that of FIG. 10, for example, as shown in FIG. 7, an inter-network interface (ne
twork to network interface: hereinafter referred to as “NNI”). Again,
NNI may be synchronous / asynchronous.

In this case as well, it is substantially similar to the exchange system shown in FIG. 1, but only the parts that largely differ from the explanations in FIGS. 1 to 6 will be explained in further detail.

First, in the case of normal normal data communication on the NNI, another exchange (network) 10A is interposed between the terminal 21 and the exchange (network) 10, and this exchange 10A has been described above. Information similar to that of the terminal 21 in FIG. 1 and FIG. 2 is exchanged.

A multicast PVC status confirmation sequence on the NNI is schematically shown in FIG. (1) When the terminal 21 transmits a multicast PVC status confirmation request message, that is, a multicast SE message via the exchange 10A, the SE message data is transferred to the communication control device 41 via the multicast server 51 in the exchange 10. At this time, the multicast server 51 does not perform any particular processing on the received data,
It merely transfers the SE message to the communication control device 41.

(2) The communication control device 41 performs a judgment process on the received message as to whether or not the received message is valid according to the protocol regulation. If it is judged that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) Based on the stored multicast conditions, the multicast server 51 uses the multicast P
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected and the status is confirmed for the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which confirms the status of each subscriber terminal line and collects information, collects the collected information and returns a response to the communication control device 41. (5) The communication control device 41 edits the multicast PVC status notification message, that is, the multicast S message, based on the response information returned from the multicast server 51, and the multicast server 51 and the exchange 1
It is returned to the terminal 21 via 0A.

In this case, the multicast S message is, as shown in the concept of FIG. 4, for each PVC # 1, PVC # 2 ... PVC of the multicast PVC set for one data link from the terminal to the exchange 10. It is edited so as to include state information listing the states of #n.

As the SE message and the S message in the frame relay system described above, the same format as in the example shown in FIGS. 5 and 6 can be used also in the case of NNI.

[Third Embodiment] FIG. 9 shows the configuration of a third embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention.

The exchange system of FIG. 9 has terminals 21 and 31, 32, ... 3n similar to the system of FIG.
Further, an exchange 11 different from the exchange 10 in FIG.
have.

Since the terminals 21 and 31, 32, ... 3n are the same as those in FIG. 1, their details will not be described here. Also in this case, the terminal 21 has the terminals 31 to 31.
I have a multicast PVC contract with 3n and I have it registered with the system. In this case, the terminal 21 is the calling terminal and the terminals 31 to 3n are the called terminals.

The exchange 11 comprises a communication control device 42, a multicast server 51, line accommodation devices 61, 62 ... 6
N and 71, 72 ... 7n. Exchange 11
1 is different from the case of FIG. 1 only in the operation of the communication control device 42, and is otherwise the same as the system of FIG. Also in this case, the case where it is applied to the UNI of the frame relay network is described. UNI may be synchronous / asynchronous.

The multicast server 51 stores the multicast condition according to the registered content of the multicast PVC between the terminal 21 and the terminals 31 to 3n. The multicast server 51 transfers the data received from the terminal 21 via the line accommodation device 62 to the communication control device 42,
The data sent from the communication control device 42 is transferred to the terminal 21 via the line accommodation device 62.

Further, at the time of normal data communication, the multicast server 51 uses the data provided from the communication control device 42 for the terminals 31 to 3n according to the multicast condition.
The same data is simultaneously transmitted via the line accommodation devices 71 to 7n. When checking the PVC status, the multicast server 51 determines from the stored multicast condition that
The target destination terminal is selected, the state confirmation is performed on the line accommodation devices 71 to 7n accommodating the corresponding terminals 31 to 3n, and the state of each line accommodation device 71 to 7n is collected, The information is collected and a response is returned to the communication control device 42.

During normal data communication, the communication control device 42 performs protocol processing necessary for data communication on the data transmitted from the terminal 21 and transferred from the multicast server 51, and then transmits the data to the terminals 31 to 3n. To the multicast server 51.

Further, when the PVC status is confirmed, the communication control device 42 receives the SE message transmitted from the terminal 21, and performs message judgment processing such as judgment as to whether or not the SE message is valid according to the protocol regulation. , The multicast server 5 determines that the SE message is valid.
The information collection request is sent to 1. As a result of this information collection request, when the response information of the states of the line accommodating devices 71 to 7n collected and collected by the multicast server 51 is returned from the multicast server 51 to the communication control device 42, the communication control device 42 The S message is edited based on the response information and sent to the multicast server 51 to be returned to the terminal 21 via the line accommodation device 62.

In the case of this embodiment, the communication control device 42
Takes AND of all the statuses of the terminals 31 to 3n obtained from the line accommodating devices 71 to 7n via the multicast server 51, and only when all the terminals 31 to 3n under the multicast PVC are active. Edit the active S message.

Next, regarding the exchange system shown in FIG. 9, first, the sequence in the case of normal data communication on UNI will be described. (1) The terminal 21 has a contract with the terminals 31 to 3n for a multicast PVC, and this contract is registered in the system. In this case, the contract content is sent to the multicast server 51 of the exchange 10 which is a frame relay network. The multicast condition based on is stored.

(2) When the terminal 21 transmits data, the corresponding line accommodation device 62 in the exchange 10 receives the data and transfers the data to the communication control device 42 via the multicast server 51. At this time, the multicast server 51 does not perform any special processing and simply transfers the data.

(3) The communication control device 42 executes the protocol processing required for normal data communication on the received data, and transfers the resulting data to the multicast server 51 on the output side.

(4) The multicast server 51 broadcasts the same data to the corresponding terminals 31 to 3n according to the stored multicast conditions. That is, the operation of the communication control device 42 in the sequence for this normal data communication is exactly the same as that of the communication control device 42 in FIG.

Next, the multicast PVC state confirmation sequence on the UNI in the system of FIG. 9 will be described. FIG. 10 schematically shows a multicast PVC status confirmation sequence on the UNI / NNI.

(1) When the terminal 21 sends a multicast PVC status confirmation request message, that is, a multicast SE message, the corresponding line accommodation device 62 in the exchange 10 receives the SE message and controls communication via the multicast server 51. Transfer SE message data to device 42. At this time, the multicast server 5
1 does not perform any special processing on the received data and simply SE
It just forwards the message to the communication controller 42.

(2) The communication control device 42 performs a determination process on the received message as to whether or not the received message is valid according to the protocol regulation. If it is determined that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) The multicast server 51, based on the stored multicast conditions,
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected, and the state confirmation is performed on the line accommodation devices 71 to 7n that accommodate the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which has confirmed the status of each of the line accommodation devices 71 to 7n and collected information,
The collected information is collected and a response is returned to the communication control device 42.

(5) The communication control device 42 edits the multicast PVC status notification message, that is, the multicast S message, based on the response information returned from the multicast server 51, and the terminal via the multicast server 51 and the line accommodation device 62. Return to 21.

In this case, the multicast S message is, as the concept is shown in FIG. 10, for each PVC # 1, PVC # 2 ... PVC of the set multicast PVC for one data link from the terminal to the exchange 10. Edited to include state information that is active only when all states of #n are active.

An example of a specific format of the SE message and the S message that can be used in the frame relay system described above will be described with reference to FIGS. 5 and 6, for example.

The SE message shown in FIG. 5 is exactly the same in the case of the system shown in FIG. The S message shown in FIG. 6 has a multicast P of 3 bytes or less.
The information indicating the VC status is set to 3 bytes (3 octets) regardless of the number of PVCs, and only when the status of all PVCs under the multicast PVC is active, the active bit A (the third byte below the 3rd byte, The fifth byte) is set to "1", that is, active. The format of the S message in this case is a normal P that is not a multicast except for the information element identifier of the first byte.
The format can be exactly the same as the format for checking the VC status.

In this way, in the UNI network service by frame relay, in the case of performing multicast fixed connection communication, the connection state notification message in which the state information of the destination link connection under the multicast is edited is defined, By transferring it, it is possible to confirm the connection state such as disconnection of the multicast destination link connection.

As the connection status notification message, the connection status notification message including the status information that makes the status information active is used only when all the destination link connections under the multicast are active. With the almost common format, it is possible to know the status of the entire destination link connection under the multicast.

[Embodiment 4] A fourth embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is a switching system having a configuration similar to that of FIG. 9 and corresponding to a frame relay network. 11 is an embodiment when it is applied to NNI as shown in FIG. NNI may be synchronous / asynchronous.

In this case as well, substantially the same as the exchange system shown in FIG. 9, but only the part that largely differs from the description in FIGS. 9 and 10 will be described in more detail.

First, in the case of normal normal data communication on the NNI, another exchange (network) 11A is provided between the terminal 21 and the exchange 11 constituting the network.
This exchange 11A exchanges information similar to that of the terminal 21 in FIG. 9 described above.

The multicast PVC status confirmation sequence on the NNI is schematically shown in FIG. (1) When the terminal 21 transmits a multicast PVC status confirmation request message, that is, a multicast SE message via the exchange 11A, the SE message data is transferred to the communication control device 42 via the multicast server 51 in the exchange 11. At this time, the multicast server 51 does not perform any particular processing on the received data,
It simply transfers the SE message to the communication controller 42.

(2) The communication control device 42 performs a determination process on the received message as to whether or not the received message is valid according to the protocol regulation. If it is determined that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) The multicast server 51, based on the stored multicast conditions,
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected and the status is confirmed for the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which confirms the status of each subscriber terminal line and collects information, collects the collected information and returns a response to the communication control device 42. (5) The communication control device 42 edits the multicast PVC status notification message, that is, the multicast S message based on the response information returned from the multicast server 51, and the multicast server 51 and the exchange 1
It is returned to the terminal 21 via 1A.

In this case, the multicast S message is, as the concept is shown in FIG. 10, for each PVC # 1, PVC # 2, ... PVC of the set multicast PVC for one data link from the terminal to the exchange 11. Edited to include state information that is active only when all states of #n are active.

As the SE message and S message in the frame relay system described above, the same format can be used in the case of NNI. [Fifth Embodiment] FIG. 11 shows a fifth embodiment of a switching system incorporating the multicast connection status confirmation system according to the present invention.
The configuration of the embodiment of FIG.

The exchange system of FIG. 11 has terminals 21 and 31, 32 ... 3n similar to those of the system of FIG. 1, and further has an exchange 12 different from the exchange 10 of FIG.

Since the terminals 21 and 31, 32, ... 3n are the same as those in FIG. 1, their details will not be described here. Also in this case, the terminal 21 has the terminals 31 to 31.
I have a multicast PVC contract with 3n and I have it registered with the system. In this case, the terminal 21 is the calling terminal and the terminals 31 to 3n are the called terminals.
The multicast PVC contract in the case of this system is, for example, as shown in FIG.
Local terminal side connection identifier (D for frame relay
Multicast PVC identifier PVC for the terminal, which is indicated by LCI (data link connection identifier)
# 1 to PVC # n and the partner address for each,
For example, a communication partner terminal identifier such as a communication partner terminal number and the importance of each partner (significant ones are indicated by “○”) are contracted, and these are registered in advance as management data and issued. Terminal 21 and multicast server 51
Etc.

The exchange 12 includes a communication control device 43, a multicast server 51, line accommodation devices 61, 62 ... 6
N and 71, 72 ... 7n. Exchange 12
1 is different from the case of FIG. 1 only in the operation of the communication control device 43, and is otherwise the same as the system of FIG. Also in this case, the case where it is applied to the UNI of the frame relay network is described. UNI may be synchronous / asynchronous.

The multicast server 51 stores the multicast condition including the importance (whether important) of the other party of the multicast PVC according to the registered content of the multicast PVC between the terminal 21 and the terminals 31 to 3n. .
The multicast server 51 transfers the data received from the terminal 21 via the line accommodation device 62 to the communication control device 43, and transfers the data sent from the communication control device 43 to the terminal 21 via the line accommodation device 62.

Further, at the time of normal data communication, the multicast server 51 uses the data provided from the communication control device 43 for the terminals 31 to 3n according to the multicast condition.
The same data is simultaneously transmitted via the line accommodation devices 71 to 7n. At the time of checking the PVC status, the multicast server 51 selects a target destination terminal from the previously stored multicast conditions, and the corresponding terminals 31 to 31 are selected.
The state confirmation is performed on the line accommodation devices 71 to 7n accommodating n, the states of the line accommodation devices 71 to 7n are collected, the information is collected, and a response is returned to the communication control device 43.

During normal data communication, the communication control device 43 performs protocol processing necessary for data communication on the data transmitted from the terminal 21 and transferred from the multicast server 51, and then transmits the data to the terminals 31 to 3n. To the multicast server 51.

When the PVC status is confirmed, the communication control device 43 receives the SE message transmitted from the terminal 21, and performs message judgment processing such as judgment as to whether the SE message is valid according to the protocol regulation. , The multicast server 5 determines that the SE message is valid.
The information collection request is sent to 1. As a result of this information collection request, when the response information of the states of the line accommodating devices 71 to 7n collected and collected by the multicast server 51 is returned from the multicast server 51 to the communication control device 43, the communication control device 43 The S message is edited based on the response information and sent to the multicast server 51 to be returned to the terminal 21 via the line accommodation device 62.

In the case of this embodiment, the communication control device 43
Is all important information that is preset and managed by the communication control device 43 among the state information of the terminals 31 to 3n obtained from the line accommodation devices 71 to 7n via the multicast server 51 (importance column in FIG. 12). All of the ones marked with "○" are ANDed, and the multicast P
S that is active only when all the important ones of the terminals 31 to 3n under the VC are active
Edit the message.

Next, the sequence of the exchange system shown in FIG. 11 in the case of normal data communication on UNI will be described. (1) The terminal 21 has a contract with the terminals 31 to 3n for a multicast PVC, and this contract is registered in the system. In this case, the contract content is sent to the multicast server 51 of the exchange 12, which is a frame relay network. The multicast condition based on is stored.

(2) When the terminal 21 transmits data, the corresponding line accommodation device 62 in the exchange 12 receives the data and transfers the data to the communication control device 43 via the multicast server 51. At this time, the multicast server 51 does not perform any special processing and simply transfers the data.

(3) The communication control device 43 performs the protocol processing required for normal data communication on the received data, and transfers the resulting data to the multicast server 51 on the output side.

(4) The multicast server 51 broadcasts the same data to the corresponding terminals 31 to 3n according to the stored multicast conditions. That is, the operation of the communication control device 43 in the sequence for this normal data communication is exactly the same as that of the communication control device 43 in FIG.

Next, the multicast PVC state confirmation sequence on the UNI in the system of FIG. 11 will be described. FIG. 13 schematically shows a multicast PVC status confirmation sequence on the UNI / NNI.

(1) When the terminal 21 transmits a multicast PVC status confirmation request message, that is, a multicast SE message, the corresponding line accommodation device 62 in the exchange 12 receives the SE message and controls communication via the multicast server 51. Transfer the SE message data to the device 43. At this time, the multicast server 5
1 does not perform any special processing on the received data and simply SE
It just transfers the message to the communication controller 43.

(2) The communication control device 43 performs processing for judging whether or not the received message is valid according to the protocol definition, and when it is judged that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) The multicast server 51, based on the stored multicast conditions,
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected, and the state confirmation is performed on the line accommodation devices 71 to 7n that accommodate the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which has confirmed the status of each of the line accommodation devices 71 to 7n and collected information,
The collected information is collected and a response is returned to the communication control device 43.

(5) The communication control device 43 edits the multicast PVC status notification message, that is, the multicast S message, based on the response information returned from the multicast server 51, and the terminal via the multicast server 51 and the line accommodation device 62. Return to 21.

In this case, the multicast S message is, as the concept is shown in FIG. 13, for each PVC # 1, PVC # 2 ... PVC of the set multicast PVC for one data link from the terminal to the exchange 12. Edited to include state information that is active only when all the states of #n set as important, for example, PVC # 1 and PVC # 2 are active.

An example of a specific format of the SE message and S message that can be used in the frame relay system described above will be described with reference to FIGS. 5 and 6, for example.

The SE message shown in FIG. 5 is exactly the same in the case of the system shown in FIG. The S message shown in FIG. 6 has a multicast P of 3 bytes or less.
The information indicating the VC status is 3 bytes (3 octets) regardless of the number of PVCs, and the active bit A (3rd byte) is set only when the status of all the PVCs registered as important under the multicast PVC is active. The following third byte, that is, the fifth byte) is set to "1", that is, active. The format of the S message in this case can be exactly the same as the format for normal PVC status confirmation, which is not multicast, except for the information element identifier of the first byte.

In this way, in the UNI network service by frame relay, in the case of performing the multicast fixed connection communication, the connection status notification message in which the status information of the partner link connection under the multicast is edited is defined, By transferring it, it is possible to confirm the connection state such as disconnection of the multicast destination link connection.

As the connection status notification message, status information that makes status information active only when all one or more important partner link connections registered in advance among the partner link connections under the multicast are active. Since the connection status notification message containing the message is used, the necessary status of the destination link connection under the multicast can be known in the same format as in the case of no multicast service.

[Sixth Embodiment] A sixth embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is a switching system having a configuration similar to that of FIG. 12 is an embodiment when applied to NNI as shown in FIG. 7, for example. NNI may be synchronous / asynchronous.

In this case as well, substantially the same as the exchange system shown in FIG. 11, except that FIG. 11 and FIG.
Only the part that largely differs from the description in 1 will be described in more detail.

First, in the case of normal normal data communication on the NNI, another exchange (network) 12A is provided between the terminal 21 and the exchange 12 constituting the network.
This exchange 12A exchanges the same information as the terminal 21 in FIG. 11 described above.

A multicast PVC status confirmation sequence on the NNI is schematically shown in FIG. (1) When the terminal 21 transmits a multicast PVC status confirmation request message, that is, a multicast SE message via the exchange 12A, the SE message data is transferred to the communication control device 43 via the multicast server 51 in the exchange 12. At this time, the multicast server 51 does not perform any particular processing on the received data,
It merely transfers the SE message to the communication control device 43.

(2) The communication control device 43 performs a process of judging whether or not the received message is valid according to the protocol regulation, and when it is judged that the received message is a valid SE message, the multicast server 51
Request to collect information.

(3) Based on the stored multicast condition, the multicast server 51
Destination terminal that is the target of VC, that is, terminals 31 to 31
n is selected and the status is confirmed for the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which confirms the status of each subscriber terminal line and collects information, collects the collected information and returns a response to the communication control device 43. (5) The communication control device 43 edits the multicast PVC status notification message, that is, the multicast S message based on the response information returned from the multicast server 51, and the multicast server 51 and the exchange 1
It is returned to the terminal 21 via 2A.

In this case, the multicast S message is, as the concept is shown in FIG. 13, for each PVC # 1, PVC # 2 ... PVC of the set multicast PVC for one data link from the terminal to the exchange 12. Edited to include state information that is active only when all states of #n are active.

The same format can be used for the SE and S messages in the frame relay system described above even in the case of NNI. In each of the above-described embodiments, only the frame relay system for relaying data at the frame level of the data link layer, which is a relay type packet type communication system for the frame of the data link layer, is described. However, as a high-speed packet communication system in which communication data is segmented and relay-transferred in the network, a cell relay, which is also called a frame relay, can be implemented in substantially the same manner as each of the above-described embodiments. The cell relay is known as an ATM switching system as described above, and is a relay-type packet-type communication method for physical layer cells, in which data is relayed at the cell level of the physical layer for communication. To do. Hereinafter, an embodiment in which the present invention is applied to a cell relay will be described.

[Embodiment 7] A seventh embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is applied to UNI similarly to the system shown in FIGS. , A switching system having substantially the same configuration as that shown in FIGS. That is, in this system, in the exchange system shown in FIGS. 1 to 4, as shown in FIG. 14 which substantially corresponds to FIG.
The exchange 10 is an ATM exchange of a cell relay network, and the terminals 21 and 31 to 3n are terminals made of ATM terminals.

In this case, since the network system is a cell relay network system, the exchange 10 is an ATM exchange which is a cell relay network, and the terminals 21 and 31 to 3n are ATM terminals, but other operations and actions are as shown in FIG. According to the case of FIG.

As shown in the concept of FIG. 4, the multicast S message is for each PVC # 1, PVC # 2 ... PVC # n of the multicast PVC set for one data link from the terminal to the exchange 10. It is edited so as to include the status information in which the statuses of are listed.

Examples of specific formats of the SE message and S message that can be used in the above-described cell relay system are shown in FIGS. 15 and 16. FIGS. 15 and 16 correspond to FIGS. 5 and 6 in the case of the frame relay, and the Q.T. of the ITU-T recommendation, which is the standard specification of the cell relay system. 2931 Append
SPC (semi-permanent virtual cha shown in ix III
The formats of the SE message and the S message for multicast PVC status confirmation corresponding to the format of (nnel connection) are shown. Here, the SPC in the cell relay mainly means a semi-fixed connection having an incoming call notification procedure in the ISDN interface and is strictly different from the PVC, but in this case, the PVC is used.
It can be considered as a kind of fixed connection that is almost the same.

FIG. 15 is a format that defines information relating to the report type indicating the SE message. In this case, bit number 8 of the first byte (first octet)
1 is an information element identifier, and in this case, it is "01100110" indicating that it is the information of the SPC report type. In the second byte, bit number 8 indicates extension with "1", bit numbers 7 and 6 indicate coding standard,
And the bit numbers 5 to 1 indicate the information element instruction field. The third and fourth bytes indicate the report type content length, and in this case, data indicating that the length is 5 bytes (5 octets) is arranged. The fifth byte is information indicating the report type. In this case, in order to indicate the status confirmation (request) of the multicast PVC, for example, “00000111” which is not defined in the above standard is used.

FIG. 16 is a format for defining the information regarding the information element identification indicating the S message and the multicast PVC status confirmation information. In this case, the bit numbers 8 to 1 of the first byte (first octet) are information element identifiers, and in this case, they are “01100111” indicating the multicast PVC status confirmation information. In the second byte, bit number 8 is "1", indicating extension, and bit number 7
And 6 indicate the coding standard, and bit numbers 5-1 indicate the information element instruction field. The 3rd and 4th bytes indicate the report type content length. In this case, since all the PVC status information is listed, the registered PV is registered.
Data of information depending on the C number is arranged.

The fifth and subsequent bytes are information indicating the multicast PVC status, and in this case, one PV
4 bytes per C (4 octets), 4x
(Number of PVC) bytes.

The first 2 bytes of each 4 bytes are a data link connection identifier indicating a multicast PVC identifier. Bit number 8 of the 3rd byte is
It is set to "1" or "0" indicating extension, bit number 4 is set to new bit N indicating whether or not it is new, and bit number 3
Is a delete bit D indicating whether to delete, and bit number 2 is an active bit A indicating whether it is active. When the new bit N is "0", it means that it has already been given, and when it is "1", it means that it is new. Active bit A is "0"
When it means, it means inactive, and when it means “1”, it means that it is active. The bit number 8 of the 4th 1-byte is set to "1" indicating extension, and the bit numbers 5 to 1 are inactive reaso.
n) is placed.

Others are all (bit numbers 7 to 5 and bit number 1 of the third 1-byte, and bit numbers 7 and 6 of the fourth 1-byte) reserved bits, and in this case, "0". And

As described above, the first 2 bytes are the identification number assigned in advance for each multicast PVC.
This identification number is assigned between the terminal and the network or between the network and the network when the multicast PVC is contracted.

By doing so, the UN by the cell relay is
In the network service of I, in the case of performing multicast fixed connection communication, by defining a connection status notification message in which the status information of the destination link connection under the multicast is edited and transferring it,
It is possible to confirm the connection status such as disconnection of the multicast destination link connection.

In this case, since the connection status notification message in which all the status information of the partner link connections under the multicast is listed is used as the S message, it is possible to specifically know the individual status of the partner link connections under the multicast. it can.

[Embodiment 8] An eighth embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is an ATM switch of a cell relay network in a switching system having a configuration similar to that of FIG. This is an embodiment in which the exchange 10 is applied to an NNI of a cell relay network as shown in FIG. 17, for example. Also in this case, the NNI may be synchronous or asynchronous.

In the case of normal normal data communication on the NNI, another exchange (network) 10A is interposed between the terminal 21 and the exchange (network) 10, and this exchange 10A is used in the above-mentioned FIG. The same information as that of the terminal 21 is exchanged.

As shown in the concept of FIG. 4, the multicast S message is for each PVC # 1, PVC # 2 ... PVC # n of the multicast PVC set for one data link from the terminal to the exchange 10. It is edited so as to include state information in which the states of are listed.

SE in the above-mentioned cell relay system
As the message and the S message, in the case of NNI, the same format as the example shown in FIGS. 15 and 16 can be used.

[Ninth Embodiment] The switching system of FIG. 9 described in the third embodiment can be applied to a cell relay instead of a frame relay. This is the ninth embodiment of the exchange system incorporating the multicast connection status confirmation system according to the present invention.

In this case, the frame relay serves as a cell relay and the exchange 11 serves as an ATM exchange, but the rest is the same as the exchange system of FIG. The multicast server 51 stores the multicast condition according to the registered content of the multicast PVC between the terminal 21 and the terminals 31 to 3n. Multicast server 51
Transfers the data received from the terminal 21 to the communication control device 42 via the line accommodation device 62, and the data sent from the communication control device 42 to the terminal 2 via the line accommodation device 62.
Transfer to 1.

At the time of normal data communication, the multicast server 51 broadcasts the data given from the communication control device 42 to the terminals 31 to 3n complying with the multicast condition via the line accommodating devices 71 to 7n. . When checking the PVC status, the multicast server 51
Selects the target destination terminal from the stored multicast conditions, confirms the state of the line accommodation devices 71 to 7n accommodating the corresponding terminals 31 to 3n, and accommodates each line. The status of each of the devices 71 to 7n is collected, the information is collected, and a response is returned to the communication control device 42.

During normal data communication, the communication control device 42 performs protocol processing necessary for data communication on the data transmitted from the terminal 21 and transferred from the multicast server 51, and then transmits the data to the terminals 31 to 3n. To the multicast server 51.

Also, when the communication control device 42 receives the SE message of the cell relay transmitted from the terminal 21 during the PVC status confirmation, the communication control device 42 performs message determination processing such as determination as to whether the SE message is valid according to the protocol regulation. When it is determined that the SE message is valid, the multicast server 51 is requested to collect information. As a result of this information collection request, when the response information of the states of the line accommodating devices 71 to 7n collected and collected by the multicast server 51 is returned from the multicast server 51 to the communication control device 42, the communication control device 42 The S message of the cell relay is edited based on the response information and sent to the multicast server 51 to be returned to the terminal 21 via the line accommodation device 62.

In the case of this embodiment, the communication control device 42
Takes AND of all the statuses of the terminals 31 to 3n obtained from the line accommodating devices 71 to 7n via the multicast server 51, and only when all the terminals 31 to 3n under the multicast PVC are active. Edit the active S message.

Also in the above cell relay system,
For example, the SE message and S message formats shown in FIGS. 15 and 16 can be used. In this case, the S message shown in FIG.
No matter how many VCs there are 4 bytes (4 octets),
Only when all PVCs under the multicast PVC are active, the active bit A (3rd byte below the 5th byte, that is, bit number 2 of the 7th byte)
Is set to “1”, that is, active. The format of the S message in this case can be exactly the same as the format for normal PVC status confirmation, which is not multicast, except for the information element identifier of the first byte.

Thus, the UNI by the cell relay is
In the network service of, when performing multicast fixed connection communication, by defining the connection status notification message in which the status information of the destination link connection under the multicast is edited and forwarding it, the multicast destination link connection It is possible to confirm the connection state such as disconnection of the.

As the connection status notification message, the connection status notification message including the status information that makes the status information active is used only when all the destination link connections under the multicast are active. With the almost common format, it is possible to know the status of the entire destination link connection under the multicast.

Further, the exchange 11 composed of the ATM exchange of the cell relay network of the exchange system having the same configuration as that of FIG. 9 may be applied to the NNI as in the case of the fourth embodiment of the frame relay. . In this case, in the case of normal normal data communication on NNI,
Another exchange (network) 11A is interposed between the terminal 21 and the exchange 11 constituting the network, and this exchange 11A exchanges the same information as the terminal 21 in FIG. 9 described above.

[Embodiment 10] The switching system of FIG. 11 described in the fifth embodiment can be applied to a cell relay instead of a frame relay. This is the tenth embodiment of the exchange system incorporating the multicast connection status confirmation system according to the present invention.

The exchange system of FIG. 11 has an exchange 12 different from the exchange 10 of FIG. The contract of the multicast PVC in the case of this system is, for example, as shown in FIG. 12 as an example of the management data, a connection identifier of its own terminal side (cell relay, that is, V in the case of ATM).
PI (virtual path identifier) / VCI (virtual chan
channel identifier)), the identifiers PVC # 1 to PVC # n of the multicast PVC for the own terminal, the partner address for each, the communication partner terminal identifier such as the communication partner terminal number, and the importance of each partner. A contract is made, these are registered in advance as management data, and are stored in the calling terminal 21, the multicast server 51, and the like.

The multicast server 51 stores the multicast condition including information on whether or not the partner of the multicast PVC according to the registered content of the multicast PVC between the terminal 21 and the terminals 31 to 3n is important. The multicast server 51 transfers the data received from the terminal 21 via the line accommodation device 62 to the communication control device 43, and transfers the data sent from the communication control device 43 to the terminal 21 via the line accommodation device 62.

At the time of normal data communication, the multicast server 51 broadcasts the data given from the communication control device 43 to the terminals 31 to 3n according to the multicast condition via the line accommodating devices 71 to 7n. . When checking the PVC status, the multicast server 51
Selects a target destination terminal from the previously stored multicast conditions, performs a state confirmation on the line accommodation devices 71 to 7n accommodating the corresponding terminals 31 to 3n, and The state of each of the accommodation devices 71 to 7n is collected, the information is collected, and a response is returned to the communication control device 43.

During normal data communication, the communication control device 43 performs protocol processing necessary for data communication on the data transmitted from the terminal 21 and transferred from the multicast server 51, and then transmits the data to the terminals 31 to 3n. To the multicast server 51.

Further, when the PVC status is confirmed, the communication control device 43 receives the SE message transmitted from the terminal 21, and performs message judgment processing such as judgment as to whether or not the SE message is valid according to the protocol regulation. , The multicast server 5 determines that the SE message is valid.
The information collection request is sent to 1. As a result of this information collection request, when the response information of the states of the line accommodating devices 71 to 7n collected and collected by the multicast server 51 is returned from the multicast server 51 to the communication control device 43, the communication control device 43 The S message is edited based on the response information and sent to the multicast server 51 to be returned to the terminal 21 via the line accommodation device 62.

Here, the communication control device 43 is set in advance in the state information of the terminals 31 to 3n obtained from the line accommodating devices 71 to 7n via the multicast server 51 and is managed by the communication control device 43. If all of the important ones (all marked with “○” in the importance column in FIG. 12) are ANDed, and all the important ones of the terminals 31 to 3n under the multicast PVC are active Edit the S message that is only active.

As shown in the concept of FIG. 13, the multicast S message is for each PVC # 1, PVC # 2 ... PVC # n of the multicast PVC set for one data link from the terminal to the exchange 12. Those designated as important, such as PVC # 1 and PVC #
It is edited to include state information that becomes active only when all two states are active.

Also in the above cell relay system,
For example, the SE message and S message formats shown in FIGS. 15 and 16 can be used. In this case, the S message shown in FIG.
No matter how many VCs there are 4 bytes (4 octets),
Only when the status of all PVCs registered as important under the multicast PVC is active, the active bit A (the third byte of the fifth byte or less, that is, the bit number 2 of the seventh byte) is set to "1", that is, active. And The format of the S message in this case is
Except for the information element identifier of the first byte, the format is the same as the normal PVC status confirmation format other than multicast.

By doing this, the UN by the cell relay is
In the network service of I, in the case of performing multicast fixed connection communication, by defining a connection status notification message in which the status information of the destination link connection under the multicast is edited and transferring it,
It is possible to confirm the connection status such as disconnection of the multicast destination link connection.

As the connection status notification message, status information that makes the status information active only when all one or more important partner link connections registered in advance among the partner link connections under the multicast are active. Since the connection status notification message containing the message is used, the necessary status of the destination link connection under the multicast can be known in the same format as in the case of no multicast service.

Further, the exchange 12 composed of the ATM exchange of the cell relay network of the exchange system having the same configuration as that of FIG. 11 may be applied to the NNI as in the case of the sixth embodiment of the frame relay. . In this case, in the case of normal normal data communication on the NNI, another exchange (network) 12A is interposed between the terminal 21 and the exchange 12 constituting the network, and this exchange 12A is the same as the one described above. Terminal 21 at 11
The same information will be exchanged.

[Eleventh Embodiment] An eleventh embodiment of a switching system incorporating a multicast connection status confirmation system according to the present invention is a switching system applied to a service interwork between a frame relay network and a cell relay network. is there. That is, in this system, in the switching system shown in FIGS. 1 to 4, as shown in FIG. 18, which substantially corresponds to FIG. 7, the switching device 10 is an ATM switching device of the cell relay network, and the terminals 31 to 31.
3n is a terminal composed of an ATM terminal, and the terminal 21 is a frame relay terminal. A frame relay switch (frame relay network) 10A is interposed between the terminal 21 and the ATM switch 10, and this switch 10A is described above. Information similar to that of the terminal 21 in FIGS. 1 and 2 is exchanged. That is, since it extends over the frame relay network system and the cell relay network system, the exchange 10 is an ATM exchange that is a cell relay network, the exchange 10A is an ATM exchange that is a frame relay network, and the terminal 21 is a frame relay terminal and a terminal. 31 to 3n are ATM terminals.

A multicast PVC state confirmation sequence on the service interwork is schematically shown in FIG. (1) When the frame relay terminal 21 transmits a multicast PVC status confirmation request message, that is, a multicast SE message via the frame relay exchange 10A, the multicast server 5 in the ATM exchange 10
The SE message data is transferred to the communication control device 41 via 1. (2) The communication control device 41 performs a determination process on the received message as to whether or not the received message is valid according to the protocol specification,
If it is determined that the received message is a valid SE message, the multicast server 51 is requested to collect information.

(3) Based on the stored multicast conditions, the multicast server 51 uses the multicast P
Destination terminal that is the target of VC, that is, ATM terminal 3
1 to 3n are selected, and the status is confirmed for the subscriber terminal lines of the corresponding terminals 31 to 3n.

(4) The multicast server 51, which has confirmed the status of each subscriber terminal line and collected information, collects the collected information and returns a response to the communication control device 41. (5) The communication control device 41 edits the multicast PVC status notification message, that is, the multicast S message based on the response information returned from the multicast server 51, and the frame relay terminal 21 via the multicast server 51 and the frame relay switch 10A. Return to.

In this case, in the first pattern, the multicast S message is the multicast P set for one data link from the terminal to the exchange 10.
It is edited so as to include state information in which the states of each PVC # 1, PVC # 2 ... PVC # n of the VC are listed.

In the second pattern, the multicast S message is for each PV of the set multicast PVC for one data link from the terminal to the exchange 10.
Edited to include state information such that C # 1, PVC # 2 ... PVC # n are active only when all states are active.

In the third pattern, the multicast S message is for each PV of the set multicast PVC for one data link from the terminal to the exchange 10.
C # 1, PVC # 2 ... Edited to include state information that is active only when all important states of PVC # n are active.

In the case of the above service interwork, A
The cell format is converted between the TM switch 10 and the frame relay switch 10A, and the SE message and S message formats are also converted.

[0179]

As described above, according to the present invention,
In relay type network services such as frame relay and cell relay, when performing multicast fixed connection communication, define a connection status notification message that edits the status information of the destination link connection under multicast and transfer it. As a result, it is possible to provide a multicast connection state confirmation method and device that can confirm the connection state such as disconnection of the destination link connection of the multicast.

As the connection status notification message, if the connection status notification message in which all the status information of the destination link connections under the multicast is enumerated is used, the format is different from the case where it is not a multicast service, but the partner under the multicast The individual states of the destination link connection can be specifically known.

As the connection status notification message, a connection status notification message including status information that activates the status information is used only when all the destination link connections under the multicast are active. In the same format as when it is not, it is possible to know the status of the entire destination link connection under the multicast.

As the connection status notification message, a connection including status information that makes the status information active only when one or more previously registered partner link connections among the partner link connections under the multicast are all active. By using the status notification message, it is possible to know the necessary status of the destination link connection under the multicast in the same format as in the case where the multicast service is not used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an exchange system according to a first embodiment of the present invention.

FIG. 2 is a system block diagram for explaining a state confirmation of a frame relay UNI according to the system of FIG.

FIG. 3 is a diagram illustrating a UNI multicast state confirmation sequence according to the system of FIG. 1;

4 is a diagram for explaining a multicast state confirmation method according to the system of FIG.

FIG. 5: Multicast PV in frame relay system
It is a figure for demonstrating the example of the format of the SE message of C.

FIG. 6 is a multicast PV in the frame relay system.
It is a figure for explaining the example of the format of the S message of C.

FIG. 7 is a system block diagram for explaining a state confirmation of a frame relay NNI of the switching system according to the second embodiment of the present invention.

8 is a diagram for explaining an NNI multicast state confirmation sequence according to the system of FIG. 7;

FIG. 9 is a block diagram showing a configuration of an exchange system according to a third embodiment of the present invention.

10 is a diagram for explaining a UNI / NNI multicast state confirmation method according to the system of FIG. 9;

FIG. 11 is a block diagram showing a configuration of an exchange system according to a fifth embodiment of the present invention.

FIG. 12 is a diagram for explaining system management data according to the system of FIG. 11.

13 is a diagram for explaining a UNI / NNI multicast state confirmation method according to the system of FIG. 11;

FIG. 14 is a system block diagram for explaining a state confirmation of a cell relay UNI of a switching system according to a seventh embodiment of the present invention.

FIG. 15: Multicast PVC in cell relay system
5 is a diagram for explaining an example of the format of the SE message of FIG.

FIG. 16: Multicast PVC in cell relay system
6 is a diagram for explaining an example of the format of the S message of FIG.

FIG. 17 is a system block diagram for explaining a state confirmation of a cell relay NNI of a switching system according to a ninth embodiment of the present invention.

FIG. 18 is a system block diagram for explaining status confirmation in service interwork between the frame relay network and the cell relay network of the switching system according to the eleventh embodiment of the present invention.

FIG. 19 is a diagram for explaining a multicast status confirmation sequence of service interwork according to the system of FIG. 18;

[Explanation of symbols]

10, 10A, 11, 11A, 12, 12A ... Exchange (network) 21, 31-3n ... Terminal 41, 42, 43 ... Communication control device 51 ... Multicast server 61-6N, 71-7n ... Line accommodation device

Claims (42)

[Claims] 1. On a high-speed packet communication system that divides communication data into segments and relay-transfers in the network, a multicast service that performs broadcast communication in which at least one of fixed link connections is plural is a subordinate of the multicast service. A multicast connection status confirmation method characterized by defining a connection status notification message that enumerates the status information of all destination link connections, and providing the connection status confirmation for each multicast link connection. 2. The multicast connection status confirmation method according to claim 1, wherein the high-speed packet communication system is a frame relay network system. 3. The multicast connection status confirmation method according to claim 1, wherein the high-speed packet communication system is a cell relay network system. 4. The multicast connection according to claim 1, wherein connection state confirmation by a connection state notification message for each multicast link connection is applied to the link connection of the user network interface. How to check the status. 5. The multicast connection according to claim 1, wherein connection state confirmation by a connection state notification message for each multicast link connection is applied to the link connection of the network-to-network interface. How to check the status. 6. The multicast connection according to claim 1, wherein connection state confirmation by a connection state notification message for each multicast link connection is applied to an interworking function between the frame relay network and the cell relay network. How to check the status. 7. The link connection by the fixed connection comprises:
The multicast connection state confirmation method according to claim 1, further comprising a link connection by a semi-fixed connection. 8. In a high-speed packet communication system that divides communication data into segments and relay-transfers in the network, a multicast service that performs broadcast communication in which at least one of fixed link connections is plural is a subordinate of the multicast service. Multicast connection status confirmation method characterized by defining a connection status notification message containing status information that activates the status only when all destination link connections are active, and providing the confirmation of the connection status of the multicast link connection . 9. The multicast connection status confirmation method according to claim 8, wherein the high-speed packet communication system is a frame relay network system. 10. The multicast connection status confirmation method according to claim 8, wherein the high-speed packet communication system is a cell relay network system. 11. The connection state confirmation by a connection state notification message of a multicast link connection is applied to a link connection of a user network interface.
The method for checking the multicast connection status described in Section. 12. The multicast connection status according to claim 8, wherein connection status confirmation by a connection status notification message of a multicast link connection is applied to a link connection of an inter-network interface. Confirmation method. 13. The multicast connection status according to claim 8, wherein connection status confirmation by a connection status notification message of a multicast link connection is applied to an interworking function between the frame relay network and the cell relay network. Confirmation method. 14. The multicast connection status confirmation method according to claim 8, wherein the link connection by the fixed connection includes a link connection by the semi-fixed connection. 15. A multicast subordinate partner in a multicast service for performing broadcast communication in which at least one of fixed link connections is plural on a high-speed packet communication system in which communication data is segmented and relay-transferred in a network. When one or more important destination connections among the destination link connections are registered in advance when the multicast contract is registered, and all the above-mentioned one or more important destination connections among the destination link connections under the multicast are all active. A multicast connection status confirmation method characterized in that a connection status notification message containing status information that activates only the status is defined and used to confirm the connection status of the multicast link connection. 16. The multicast connection status confirmation method according to claim 15, wherein the high-speed packet communication system is a frame relay network system. 17. The multicast connection status confirmation method according to claim 15, wherein the high-speed packet communication system is a cell relay network system. 18. The multicast connection status according to claim 15, wherein connection status confirmation by a connection status notification message of a multicast link connection is applied to the link connection of the user network interface. Confirmation method. 19. The multicast connection status according to claim 15, wherein connection status confirmation by a connection status notification message of a multicast link connection is applied to the link connection of the inter-network interface. Confirmation method. 20. The multicast connection status according to claim 15, wherein connection status confirmation by a connection status notification message of a multicast link connection is applied to an interworking function between the frame relay network and the cell relay network. Confirmation method. 21. The multicast connection status confirmation method according to claim 15, wherein the link connection by the fixed connection includes a link connection by the semi-fixed connection. 22. By high-speed packet communication in which communication data is segmented and relay-transferred in the network,
A multicast connection state confirmation device in a high-speed packet communication system for providing a service including a multicast service for performing broadcast communication in which at least one of link connections by fixed connection is plural, and a multicast in response to a connection state confirmation request message. A status collection unit that collects status information of all subordinate link connections under the control, and a connection status notification message that lists the status information of all the subordinate link connections under multicast based on the collection result by the status collection unit Receiving the connection status confirmation request message from the connection status confirmation request source connection and giving it to the status collecting means, and the connection status notification message edited by the message editing means to confirm the connection status. Multicast connection status confirmation apparatus characterized by comprising a transfer control means for returning to Motomemoto connection. 23. The multicast connection status confirmation device according to claim 22, wherein the high-speed packet communication system is a frame relay network system. 24. The multicast connection status confirmation device according to claim 22, wherein the high-speed packet communication system is a cell relay network system. 25. The multicast connection status confirmation apparatus according to claim 22, wherein the link connection is a user network interface link connection. 26. The multicast connection status confirmation device according to claim 22, wherein the link connection is a link connection of an inter-network interface. 27. The multicast connection status confirmation device according to claim 22, wherein the link connection is a link connection based on an interworking function between the frame relay network and the cell relay network. 28. The multicast connection status confirmation device according to claim 22, wherein the fixed connection includes a semi-fixed link connection. 29. By high-speed packet communication in which communication data is segmented and relay-transferred in a network,
A multicast connection state confirmation device in a high-speed packet communication system for providing a service including a multicast service for performing broadcast communication in which at least one of link connections by fixed connection is plural, and a multicast in response to a connection state confirmation request message. A state collecting means for collecting state information of all subordinate link connections under the control, and a state in which the state is activated only when all the subordinate link connections under the multicast are active based on the collection result by the state collecting means. Message editing means for editing a connection status notification message including information, and receiving the connection status confirmation request message from the connection status confirmation requesting connection and giving it to the status collecting means, and editing by the message editing means The connection state notification message, the multicast connection status confirmation apparatus characterized by comprising a transfer control means for returning to the connection status confirmation requesting connection. 30. The multicast connection status confirmation device according to claim 29, wherein the high-speed packet communication system is a frame relay network system. 31. The multicast connection status confirmation device according to claim 29, wherein the high-speed packet communication system is a cell relay network system. 32. The multicast connection status confirmation device according to claim 29, wherein the link connection is a link connection of a user network interface. 33. The multicast connection status confirmation device according to claim 29, wherein the link connection is a link connection of an inter-network interface. 34. The multicast connection status confirmation apparatus according to claim 29, wherein the link connection is a link connection based on an interworking function between the frame relay network and the cell relay network. 35. The multicast connection status confirmation device according to claim 29, wherein the fixed connection includes a semi-fixed link connection. 36. High-speed packet communication in which communication data is segmented and relay-transferred in a network,
A multicast connection state confirmation device in a high-speed packet communication system for providing a service including a multicast service, in which at least one of fixed link connection is plural, which is one of link destination link connections under multicast. Important party registration means for registering one or more important party connections in advance, state collecting means for collecting state information of all the destination link connections under the multicast in response to a connection state confirmation request message, and said state A connection state including state information that activates the state only when all of the registered one or more important destination link connections among the destination link connections under the multicast are active based on the collection result by the collecting means. Notification message Message editing means for editing a message, receiving the connection status confirmation request message from the connection status confirmation requesting connection and giving it to the status collecting means, and the connection status notification message edited by the message editing means, A multicast connection state confirmation device, comprising: a transfer control means for returning the connection state confirmation requesting connection. 37. The multicast connection status confirmation device according to claim 36, wherein the high-speed packet communication system is a frame relay network system. 38. The multicast connection status confirmation device according to claim 36, wherein the high-speed packet communication system is a cell relay network system. 39. The multicast connection status confirmation device according to claim 36, wherein the link connection is a link connection of a user network interface. 40. The multicast connection status confirmation device according to claim 36, wherein the link connection is a link connection of an inter-network interface. 41. The multicast connection status confirmation device according to claim 36, wherein the link connection is a link connection based on an interworking function between the frame relay network and the cell relay network. 42. The multicast connection status confirmation device according to claim 36, wherein the fixed connection link connection includes a semi-fixed connection link connection.