JPS62202632A - Packet exchange - Google Patents

Abstract

PURPOSE:To facilitate the discrimination processing of a corresponding call memory by sending an inter-station call disconnection request packet added with call identification information including a fast disconnection display to an incoming station when a call disconnection request comes before the end of call setting. CONSTITUTION:When a call disconnection request packet J is sent from a terminal equipment 1 before a call is confirmed between a call terminal equipment 1 and an incoming terminal equipment 3, an exchange processing section 6 discriminates a call status from a call memory 9 based on a logic channel number A1 in a packet J. When the result comes after the call request packet reception processing, an inter-station call disconnection request packet K making a fast disconnection display B5 effective is sent to an incoming station 10 together with a call station number B1. An exchange processing section 11 of the incoming station 10 discriminates the display B5, references a call memory reference table 14, finds out a relevant call memory 15 and sends a call disconnection request packet including the logic channel number C1 to the incoming terminal equipment.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a packet switching device used to configure a packet switching network that exchanges information in units of packets as predetermined unit blocks, and in particular, to The present invention relates to a packet switching device that facilitates memory scanning.

[Conventional technology]

FIG. 2 is a block diagram showing a conventionally commonly used packet switching device. In the figure, 1 is a calling terminal that issues a communication request, and 2 is a calling station connected to the calling terminal 1, which has a switching processing section 2a and a call memory 2b for holding the call status. ing. 3 is a called terminal that is a communication partner of the calling terminal 1, and 4 is a called station to which the called terminal 3 is connected, and similarly to the calling station 2, it maintains the call status with the switching processing unit 4a. It is equipped with a call memory 4b. and,
The called station 4 and the calling station 2 are connected to each other directly or via another station.

The operation of the packet switching device with the above configuration will be explained below.

When the calling terminal 1 calls the called terminal 3 and transmits packets of information between the two, first the calling terminal l
is logical channel number AI and call setup request code A2
A call setting request packet 1-A containing destination information such as the following is transmitted to the calling station 2. When the calling station 2 receives the call setup request packet A, the switching processing unit 2a installed therein
Call memory 2b provided to hold call status
The received call setting request packet A is allocated to the call setting request packet A, and a calling link number A3 for identifying this call is added and stored. In addition to the storage area for the logical channel number A specified by the calling terminal 1 and the storage area for the above-mentioned outgoing link number A:1, the call memory 2b also has a storage area for the called station 4.
It has a storage area for the incoming link number A4, which will be supplied later from the link number A4.

Next, the switching processing unit 2a identifies the called terminal 3 and the called station 4 that accommodates this called terminal 3 from the destination information specified by the call setup request bucket A supplied from the calling terminal l. Then, it transmits an inter-office call setup request packet B to the identified called station 4.

This inter-office call setup request bucket I-B includes a called station number B1 and a calling station number B2 in addition to the calling link number A3 and the called link number A4 of the call setting request packet A9 described above. However, the terminating link number A4 remains empty because it has not yet been sent from the terminating station 4.

On the other hand, when the exchange processing unit 4a of the called station 4 receives the inter-office call setup request packet sor l-B sent from the calling station 2, it identifies the called terminal 3 from the contents and A logical channel number 8.3 to be used for communication between the call terminal 3 and the called terminal 3 is determined. Then, the exchange processing unit 4a allocates a call memory 4b for holding the state of the call, and stores the originating link number B4 for identifying the call in the allocated call memory 4b. The call memory 4b also stores an inter-office call setting request packet sent from the calling station 2.
The outgoing link number A3 included in the incoming link number B
, is stored as .

Next, the exchange processing unit 4a transmits an incoming call packet C including a logical channel number B and an incoming call code C3 to the called terminal 3, thereby indicating that a connection request has arrived. , to notify.

Here, if the called terminal 3 is ready to receive the call, the called terminal 3 sends the called reception packet ID, which is the call reception code DI including the call code CI and the logical channel number B3, to the call reception packet ID. Notification is made by transmitting to station 4. The switching processing unit 4a of the called station 4 identifies the logical channel number B3 included in the received call acceptance packet D sent from the called terminal 3. Then, the outgoing link number B4 and the incoming link number B are read from the call memory 4b with which the identified logical channel number B matches, and the incoming call is accepted by adding the incoming station number B and the incoming station number B2 to these. It is transmitted together with packet D to calling station 2 as interoffice acceptance packet E.

When the calling station 2 receives the inter-office reception packet I-E, the calling station 2 accepts the incoming call at the incoming link number A4 in the call memory 2b that matches the outgoing link number A indicated by the incoming link number B included therein. The outgoing link number B4 sent in packet E is stored as the incoming link number A4. When the storage of the outgoing link number is completed in this way, the exchange processing unit 2a transmits the connection completion packet I-F to the calling terminal 1, thereby transmitting the logical channel number A included in the connection completion packet F. , and the connection completion code F1 is used to notify the completion of the connection. By executing such processing, a call is established between the calling terminal 12, the calling station 2, the called station 4, and the called terminal 3.

In this way, when the call setup is completed, the logical channel number A between calling terminal 1 and calling station 2 is
Transmission and reception are performed using packets G, ,G, with , as the call identifier. Furthermore, between the calling station 2 and the called station 4, the calling station 2 sends a packet HI using the incoming link number A4 as the call identifier, and the called station 4 uses the incoming link number B as the identifier. Transmission and reception are performed by transmitting packet H2 to calling station 2. Furthermore, between the called station 4 and the called terminal 3, a logical channel number B is used.

Transmission and reception are performed using packets I, , I2 having identifiers.

Next, the normal procedure for disconnecting a call will be described for the case where the calling party disconnects the call. The calling terminal 1 as the call disconnection requesting side transmits a call disconnection request packet J including the logical channel number A1 to the calling station 2. When the calling station 2 receives this call disconnection request packet J, the calling station 2 receives the logical channel number A contained therein.

The call memory 2b storing the same logical channel number A is read out. Then, the calling link number A3. which is stored in the call memory 2b. The terminating link number A4 is extracted, and the terminating station number B12, the originating station number B2, and the call disconnection request packet J are added thereto to generate an interoffice call disconnection request packet K, which is transmitted to the terminating station 4. When the called station 4 receives this inter-office call disconnection request packet I-K, the switching processing unit 4
A reads the call memory 4b which stores the outgoing link number B4 which is the same as the incoming link number A4 included in the interoffice call disconnection request bucket l-K. Then, the logical channel number B3 stored in the call memory 4b is extracted, a call disconnection instruction bucket) L is generated, and the generated call disconnection instruction bucket L is transmitted to the called terminal 3. When the called terminal 3 receives this call disconnection instruction packet L, it disconnects the call and transmits a call disconnection confirmation packet M containing the logical channel number B to the called station 4. In the called station 4 that has received the call disconnection confirmation packet M, the switching processing unit 4a selects the logical channel number B3 included in the call disconnection confirmation packet M.
The call memory 4b that stores the same logical channel number B3 is read out, and the outgoing link number B4 and incoming link number BS stored therein are retrieved, and in addition, the incoming station number B1, the outgoing station number B2, and the incoming link number BS are read out. The inter-station call disconnection confirmation packet N generated by adding the call disconnection confirmation packet M is transmitted to the calling station 2, and at the same time, the call memory 4b is released.

When the calling station 2 receives the inter-office call disconnection confirmation packet N, the switching processing unit 2a stores the outgoing link number A, which is the same as the incoming link number B included in this inter-office call disconnection confirmation packet N. The current call memory 7a is read out. The logical channel number A1 stored in this call memory 7a
The call disconnection confirmation packet O generated by reading the call disconnection confirmation packet O is sent to the calling terminal 1, and the call memory 2b is released, thereby completing the normal disconnection of the call.

Next, as shown in Figure 3, the calling terminal 1
When a call disconnection request packet J is generated, the call is disconnected according to the following procedure. First, when the calling station 2 receives the call disconnection request packet J, the switching processing unit 2a receives the logical channel number A included in the call disconnection request packet J.
, attempts to obtain the incoming link number A4 by reading the call memory 2b which stores the same logical channel number as . However, at this point, the originating link number B is unknown because it has not yet been sent from the called station 4. Therefore, the exchange processing unit 2a transmits the inter-office call disconnection request bucket IK in which the incoming link number A4 is empty to the called station 4. Since the incoming link number A4 included in the inter-office call disconnection request packet K does not indicate anything, the switching processing unit 4a of the called station 4 scans the call memory of its own station and selects the outgoing link number A3. The corresponding call memory 4b is obtained by searching the call memory having the incoming link number B5 that will fail. Then, by reading the contents of the call memory 4b determined by this search, the logical channel number B is extracted, a call disconnection instruction packet L is generated, and the packet L is transmitted to the called terminal 3.

When the called terminal 3 receives this call disconnection instruction bucket)L,
disconnecting the call and including the logical channel number B3;
A call disconnection confirmation packet l-M is transmitted to the called station 4. The called station 4 that has received the call disconnection confirmation bucket (call disconnection confirmation bucket)
A reads the call memory 4b that stores the same logical channel number B as the logical channel number B3 included in the call disconnection confirmation bucket) M, and reads outgoing link number B4, incoming link number B, and the incoming link number B stored therein. The inter-office call disconnection confirmation packet N is generated by adding the terminating station number B'l r originating station number B2 and call disconnection confirmation bucket) M.
When the calling station 2 receives the inter-office call disconnection confirmation bucket (N), it simultaneously releases the call memory 4b and transmits it to the calling station 2.
The call memory 7a in which the exchange processing unit 2a stores the outgoing link number A3, which is the same as the incoming link number B included in this interoffice call disconnection confirmation packet N, is read out. And this call.

The call disconnection confirmation packet O generated by reading the logical channel number A stored in the memory 7a is transmitted to the calling terminal l.
The disconnection of the call is completed by transmitting the call to the call memory 2b and releasing the call memory 2b.

[Problem that the invention seeks to solve]

Since conventional packet switching equipment is configured as described above, the calling station's calling link number is stored in the call memory of the calling station only when the call setup between the calling terminal and the called terminal is completed. Stored as the incoming link number. For this reason, when a call disconnection request is issued from a calling terminal during call setup, even if the calling station reads its own call memory, it cannot know the originating link number of the called station. Therefore, the calling station will transmit to the called station an interoffice call disconnection request packet with the called link number in an empty state. As a result, the called station searches the call memory that has the incoming link number that matches the outgoing link number included in the inter-office call disconnection request packet, reads out the logical channel number stored therein, and reads out the logical channel number stored therein. A call disconnection instruction packet must be generated to be transmitted to 3. Therefore, there is a problem in that the processing load required for the switching processing section of the called station to scan the call memory and read out the logical channel number becomes extremely large.

This invention was made to solve the above-mentioned problems.If the calling terminal issues a disconnection request before the call between the calling terminal and the called terminal is set up, the It is an object of the present invention to provide a packet switching device that allows a switching processing unit of a station to quickly and easily search a call memory in which a logical channel number for a called terminal to be disconnected is stored.

[Means for solving problems]

A packet switching device according to the present invention includes a calling station that accommodates a calling terminal, and a called station that accommodates a called terminal and is connected to the calling station directly or through another station. As a result, in a packet switching device that exchanges data on a packet-by-packet basis, information obtained by exchanging an originating link number determined by the calling station itself and an originating link number determined by the called station as an incoming link number. Find the corresponding call memory from a call memory that stores call identification information, a call memory table in which the calling link number and the address of the call memory are associated, and a logical channel number supplied from the calling terminal. and the corresponding call memory from the call memory reference table based on the logical channel number included in the call disconnection request packet sent from the calling terminal when this packet is received. In addition to reading out the call status by determining the call status, if the call disconnection request packet is received before the call setup is completed, indicating that the outgoing link number and the incoming link number stored in the call memory have not been set. An inter-office call disconnection request packet with call identification information including an early disconnection indication etc. is generated and transmitted to the called station, and the call disconnection request packet sent from the calling terminal is received after the call setup is completed. If so, an exchange processing unit that generates an inter-office call disconnection request packet to which call identification information consisting of an originating link number, an incoming link number, etc. stored in the call memory is added, and transmits it to the terminating station; configuring the called station with a call memory having the same configuration as the calling station, a first call memory reference table, and a second call memory that finds a corresponding call memory from the calling station number and the incoming link number for the own station. and a free logical channel number between the call memory table and the called terminal from the call memory table when receiving an inter-office call request packet supplied from the calling station. , stores the acquired call memory address in the corresponding logical channel number location of the first call memory reference table, and stores the call memory address specified by the calling link number determined by the local station and the inter-station call setup request packet in the call memory. The outgoing link is stored as the incoming link number, and the call memory address is stored in the corresponding location of the second call memory reference table, and when an inter-station call disconnect request packet is received from the other station, early disconnection is performed If the display is displayed, the corresponding call memory within the local station is determined from the call memory reference table based on the calling station number and calling link number specified by the inter-office call disconnection request packet, and the call is quickly disconnected. If the display is not performed, the call containing the logical channel number stored in this call memory is disconnected by determining the corresponding call memory in the call memory table based on the specified incoming link number. The switching processing section generates an instruction packet and transmits it to the called terminal to disconnect the call.

(Function) In the packet switching device of the present invention, when the switching processing unit constituting the calling station receives a call disconnection request packet from the calling terminal before the call setup is completed, the packet switching device receives the calling link number stored in the call memory. An exchange process that generates an inter-office call disconnection request packet with call identification information including an early disconnection indication indicating that the incoming link number has not been set, transmits it to the called station, and configures the called station. If the received inter-office call disconnection request packet indicates early disconnection, the unit calculates the internal call from the call memory reference table based on the calling station number and calling link number specified by the inter-office call disconnection request packet. The device determines the corresponding call memory, generates a call disconnection instruction packet containing the logical channel number stored in this call memory, and transmits it to the landing terminal, thereby disconnecting the call.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, reference numeral 5 denotes a calling station to which the calling terminal 1 is connected, serving as a first packet switching means.

The calling station 5 has a switching processing section 6, a call memory table 7, and a call memory reference table 8. Further, the call memory table 7 has a large number of call memories 9 therein. Inside this call memory 9, there is a calling link number field 9a.

A called link number field 9b, a logical channel number field 9c, a call status field 9d, and a called station number field 9e are provided, and a call memory address 8a is stored inside the call memory reference table 8. There is. Reference numeral 10 denotes a called station as a second packet switching means that accommodates the called terminal 3. The called station 10, like the calling station 2, has a switching processing section 11, a call memory table 12, and a first . The call memory table 12 has a call memory 15. Inside this call memory table 12, there is a calling link number field 1.
5a, incoming link number field 15b, logical channel number field 15c, call status field 15
d is provided, and a call memory reference table 13.14 is provided.
Call memory addresses 13a and 14a are stored in .

In the packet switching device configured in this way, when the calling station 1 transmits packet information between the calling station 1 and the called station 3, the calling station 1 first transmits the logical channel number A, the call setup request code, etc. The call setting request packet A containing the destination information is transmitted to the calling station 5. Calling station 5 is calling terminal 1
When receiving call setup request bucket) A sent from
The exchange processing unit 6 acquires a vacant call memory 9 from the call memory table 7. Next, the exchange processing unit 6 writes the currently unused outgoing link number into the outgoing link number field 9a in the call memory 9, and writes the logical channel number specified by the call setup request packet A into the logical channel number field 9C. , writes status information indicating that the call request packet has been received and processed in the call status field 9d, writes the called number in the called station number field 9e, and writes the logic included in the call setting request packet l-A in the call memory reference table 8. Channel number A1
The call memory address 8a is written to the location specified by. Next, the exchange processing unit 6 sends the call setting request (paqueso) A to the calling station number Bt of the calling station 5 + calling link number field 9.
The outgoing link number Bz stored in a, the incoming link number (not determined at this point) stored in the incoming link number field 9b, and the called station number stored in the called station field 9e. The inter-office call request bucket (bucket) B with B4 added thereto is transmitted to the called station 5.

On the other hand, when the called station 5 receives the inter-office call request bucket I-B, the switching processing unit 11
Earn 5. Then, the exchange processing unit 11
Write the currently unused outgoing link number C7 to the outgoing link status 15a in the incoming link status 15b, write the outgoing link number B2 included in the inter-office call request bucket) B as the incoming link number C2, and write the outgoing link number B2 included in the inter-office call request bucket) to the incoming link status 15b as the incoming link number C2. 15C is written as the oldest logical channel number C3 that is not currently in use among the logical channel numbers contracted with the called terminal 3.

Next, the exchange processing unit 11 writes the call memory address 13a in the location corresponding to the logical channel number C1 determined as described above, and then stores the call memory address for each destination station and the originating link number of the other station. The corresponding location in the call memory reference table 14 is set to the incoming link number B.

is determined based on the information of the called station number B4, and the address of the call memory 15 is set at that position as the call memory address 14a.
Write as. When such processing is completed, the exchange processing unit 11 stores the logical channel field 1 of the call memory 15.
The incoming call packet C containing the logical channel number C3 stored in 5c is transmitted to the called terminal 3, and thereafter, the calling terminal 1 and the called terminal 3 is established, and packets of various information are transmitted.

Next, a case will be described in which a call disconnection request packet J is generated from the calling terminal 1 before the call is confirmed between the calling terminal 1 and the called terminal 3. Calling station 5 is calling terminal 1
Upon receiving the call disconnection request packet J sent from
The exchange processing unit 6 obtains a call memory address 8a based on the logical channel number A1 included in the call disconnection request packet solenoid l-J, and retrieves the call stored in the call status field 9d from the call memory 9 indicated by this call memory address 8a. The status is determined, and if the determination result is after the call request packet has been received and processed, the same calling station number Bl + calling originating link number B29 that was added to the inter-office calling request bucket) B, and In addition to the called station number B4, an interoffice call disconnection request packet (K) with the early cutoff display Bs enabled is transmitted to the called station 10. When the called station 10 receives the inter-office call disconnection request packet K, the switching processing unit 11 determines the early disconnection indication B, and displays the early disconnection device B.

If the call memory reference table 14 is valid, the call memory address 14a is obtained based on the calling station number B1 and the calling link number B2 in the inter-office call disconnection request packet l-, and the call memory address 14a is address 14a to 8
The corresponding call memory 15 is found and a call disconnection instruction packet L containing the logical channel number C1 stored in the logical channel field 15c is transmitted to the called terminal 3. In addition, if the early disconnection display B is invalid, the call memory 15 is determined from the corresponding call memory address 14a in the call memory reference table 14 from the incoming link number B3 in the inter-office call disconnection request packet. ing. Then, the call disconnection instruction packet L containing the logical channel number C1 stored in the call memory 15 is transmitted to the called terminal 3. Thereafter, call disconnection is confirmed by the same procedure as shown in FIGS. 2 and 3.

〔Effect of the invention〕

As described above, according to the present invention, when the switching processing unit constituting the calling station receives a call disconnection request packet from the calling terminal before the call setup is completed, the calling station receives the calling link number stored in the call memory and A switching processing unit that generates an inter-office call disconnection request packet with call identification information including an early disconnection indication indicating that the incoming link number has not been set, transmits it to the called station, and configures the called station. If the received inter-office call disconnection request packet/node indicates early disconnection, the call is automatically retrieved from the call memory reference table based on the originating station number and originating link number specified by the inter-office call disconnection request packet. The call is disconnected by identifying the relevant call memory within the station, generating a call disconnection instruction packet containing the logical channel number stored in this call memory, and transmitting it to the called terminal. When a call disconnection request is generated before the call setup is completed, it becomes extremely easy for the switching processing unit to identify the call memory that corresponds to the call disconnection request. There are various effects such as speeding up the processing.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a packet switching device according to an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams showing conventional packet switching devices. 1 is a calling terminal, 3 is a called terminal, 5 is a calling station, 6 is a switching processing unit, 7 is a call memory table, 8 is a call memory reference table, 9 is a call memory, 1o is a called station, 11 is a exchange processing section,
12 is a call memory table, 13.14 is a call memory reference table, and 15 is a call memory. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. (2 others)'-

Claims (3)

[Claims] (1) By being composed of a calling station that accommodates a calling terminal, and a called station that accommodates a called terminal and is connected to the calling station directly or through another station, In a packet switching device that exchanges data, the calling station stores call identification information including information obtained by exchanging an outgoing link number determined by itself and an outgoing link number determined by a called station as incoming link numbers. a call memory table in which the calling link number is associated with the address of the call memory; and a first call for finding the corresponding call memory from a logical channel number supplied from the calling terminal. Determining a corresponding call memory from the first call memory reference table based on the memory reference table and the logical channel number included in the call disconnection request packet sent from the calling terminal when this packet is received. an exchange processing unit that connects a corresponding called station by reading the call status, and the called station has a call memory having the same configuration as the calling station, a call memory table, and a first A call memory look-up table and a second
acquires a free call memory and a free logical channel number between the called terminal and the called terminal from the call memory table when receiving an inter-office call setup request packet supplied from the calling station. 1. A packet switching device comprising: a switching processing unit that connects a corresponding called terminal; (2) If the call disconnection request packet is received before the call setup is complete, the switching processing unit of the calling station determines that the originating link number and the incoming link number stored in the call memory have not been set. An inter-office call disconnection request packet with call identification information including early disconnection indication etc. is generated and transmitted to the called station, and the call disconnection request packet sent from the calling terminal is received after the call setup is completed. If so, an inter-office call disconnection request packet to which call identification information consisting of an originating link number, an incoming link number, etc. stored in the call memory is added is generated and transmitted to the called station. A packet switching device according to claim 1. (3) The switching processing unit of the called station stores the obtained call memory address in the corresponding logical channel number part of the first call memory reference table, and stores the calling link number determined by the station in the call memory. The outgoing link number specified by the inter-office call origination request packet is stored as the incoming link number, and the call memory address is stored at the corresponding location in the second call memory reference table, and the inter-office call disconnection request packet is sent from the other station. is received, if early disconnection indication is being performed, the second
Determine the corresponding call memory in the own station from the call memory reference table of the call memory table, and if early disconnection display is not performed, determine the corresponding call memory in the call memory table based on the specified incoming link number. Claim 1, wherein the call is disconnected by generating a call disconnection instruction packet containing the logical channel number stored in the call memory and transmitting it to the called terminal. The described packet switching device.