JPH04262647A - Packet exchange communication system - Google Patents

Abstract

PURPOSE:To attain the communication even between packet terminal equipments whose protocol higher than a packet level differs from each other. CONSTITUTION:The system is provided with a protocol conversion propriety discrimination means 32 and when the means 32 discriminates it that the protocol conversion is required, a caller protocol conversion adaptor sets a channel with a called protocol conversion adaptor by using a packet exchange 1, and when the means 32 discriminates it that the protocol conversion is not required, the communication is implemented between the caller packet terminal equipment and the called packet terminal equipment.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet-switched communication system for communicating between packet terminals using a packet-switched network, and more particularly to a packet-switched protocol conversion system for realizing protocol conversion.

0002

[Background Art] In communication between packet terminals using a conventional packet switching network, a protocol level for packet control is given as a condition for joining the packet switching network, and a higher level protocol is required for joining the packet switching network. This is decided freely by the participating terminal. For this reason, various procedures exist as upper-level protocols, and even if it is possible to join a packet switching network, communication will not be possible unless the upper-level protocols match.

[0003] FIG. 4 is a block diagram of a conventional packet switching network shown in, for example, Nippon Telegraph and Telephone Corporation's Packet Switching Service Interface (Second Edition).
is a packet switching network, 2a, 2b are central office switching equipment, 3a, 3
b is a line termination equipment (DCE); 4a and 4b are joining lines connecting between the central office switching equipment 2a and 2b and the line termination equipment 3a and 3b; 5 is a transmission line connecting between the central office switching equipment 2a and 2b;
6a and 6b are packet terminals that join the packet switching network 1.

Next, the operation will be explained. In FIG. 4, when a packet terminal 6a makes a call, the other party's packet terminal 6b with which it communicates is notified of the incoming call via the packet switching network 1 using the other party's packet terminal address determined by the packet control procedure, and the packet terminal When the terminal 6b performs communication, it returns a response, and this packet is notified to the packet terminal 6a that made the call via the packet switching network 1. This packet control procedure enables communication at the packet level between the packet terminal 6a and the packet terminal 6b. In this way, in the packet switching network 1, the packet terminals 6a,
Communication between the DCEs 3a and 6b is performed, and the DCEs 3a and 3b perform conversion to and inverse conversion into the signaling system within the packet switching network. Further, the central office switching equipment 2a, 2b accumulates packets based on the packet terminal address, etc., and selects a transfer route.

[0005]

[Problems to be Solved by the Invention] Conventional packet switching communication systems operate as described above, and when attempting to communicate between packet terminals using different protocols higher than the packet level, the protocol higher than the packet level There was a problem in that communication was not actually possible because the consistency of the data was not guaranteed.

The present invention was made to solve the above-mentioned problems, and it is possible to connect packet terminals with different protocols above the packet level without changing the conventional packet switching network or the internal configuration of the packet switching network. The purpose is to provide a packet switching communication method that allows communication between machines.

[0007]

[Means for Solving the Problems] In the packet switching communication system according to the present invention, subscriber attributes regarding protocols higher than the packet level of the packet terminals 6a and 6b that have joined the packet switching network 1 are held, The above-mentioned system comprises a protocol conversion necessity determining means 32 for determining whether protocol conversion is required between packet terminals attempting to start communication, and a packet control means 31 operating as a packet terminal for the packet switching network 1. A communication management device 30 connected to the packet switching network 1 is used, and it is inserted into the subscriber line connecting the packet terminals 6a, 6b and the packet switching network 1, and is used as a packet terminal for the packet switching network 1. packet terminal 6a
, 6b, the packet control means 420 operates as a packet switching network, and the protocol conversion necessity determination means 32 determines whether the packet terminal device that starts communication by using data packets requires protocol conversion. A protocol comprising a communication means 421 for inquiring whether or not the packet is rejected and receiving the response, and a protocol conversion means 422 for mutually converting a protocol higher than the packet level of the packet terminals 6a, 6b and one standard protocol. Conversion adapters 40a and 40b are used.

[0008]

[Operation] When the protocol conversion necessity determining means 32 in the communication management device 30 determines that protocol conversion is necessary,
The protocol conversion means 422 in the protocol conversion adapter on the calling side becomes available, and a communication path is established between the protocol conversion adapter on the calling side and the protocol conversion adapter on the called side using the packet switching network 1. is set, the called side protocol conversion adapter is notified that "protocol conversion is required", the protocol conversion means 422 in the called side protocol conversion adapter becomes available, and the calling side packet terminal If communication is carried out between the packet terminal on the called side and the packet terminal on the called side, and the protocol conversion necessity determining means 32 in the communication management device 30 determines that protocol conversion is not necessary, the calling side protocol conversion adapter The calling side packet terminal and the calling side are connected without any notification being given to the called side as to whether or not protocol conversion is necessary, and without using the protocol conversion means 422 in the calling side protocol conversion adapter. Communication takes place between the calling packet terminals.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of the configuration of the packet exchange communication system of this embodiment. In FIG. 1, 30 is a communication management device composed of a packet control means 31, a protocol conversion necessity determination device 32, and an internal bus 33 connecting these; 40a and 40b are protocol conversion necessity determination devices in the communication management device 30; Protocol conversion adapters that cooperate with the means 32, L30, L32aa, L32ab, L32bb
, L32ba are subscriber lines. By the way, the communication management device 30 can generally be realized by a computer, the protocol conversion necessity determining means 32 can be realized by a program running on the host processor of the computer, and the packet control means 31 can be realized by the computer. This can be realized with a communication control unit.

[0010] The protocol conversion adapter 40 (40a
, 40b) includes the components shown in FIG. 2. That is, the protocol conversion adapter 40 performs packet control to perform protocol operations as a packet switching network for the terminal side subscriber line L32aa, and protocol operations as a packet terminal for the network side subscriber line L32ab. It comprises a packet control device 42 having a means 31, and subscriber line connectors 44, 44 for connecting to subscriber lines, and the above-mentioned components are connected by internal signal lines that realize full-duplex signal transmission and reception. has been done. In addition to the packet control means 420, the packet control device 42 inquires whether the packet terminal device that starts communication requires protocol conversion.
A packet terminal connected to the protocol conversion necessity determination means 32 in the communication management device 30 and the communication means 421 that communicate with each other using DT packets (data packets) via the packet switching network 1, and the protocol conversion adapter 40. It is comprised of a protocol conversion means 422 that mutually converts a protocol higher than the packet level possessed by the devices 6 (6a, 6b) and one standard protocol defined on the packet switching network 1.

Next, the operation of this embodiment will be explained using the signal procedure shown in FIG. In order to connect the packet terminal 6a to the packet terminal 6b, when a CR packet (call request packet) S0 containing the subscriber number of the packet terminal 6b is transmitted, a protocol conversion is inserted between the subscriber lines L32aa and L32ab. The adapter 40a temporarily stores the contents, and stores the contents of the C, which includes the subscriber number of the communication management device 30, which is preset inside the protocol conversion adapter 40a.
Send R packet S1. When the packet switching network 1 receives the CR packet S1, it sends a CN packet (incoming call packet) to the packet control means 31 inside the communication management device 30.
Send S2. When the packet control means 31 receives the CN packet S2, it notifies the protocol conversion necessity determination means 32 of the incoming call, and also sends the packet to the packet switching network 1.
A CA packet (incoming call acceptance packet) S3 is transmitted. When the packet switching network 1 receives the CA packet S3, it transmits a CC packet (call confirmation packet) S4 to the protocol conversion adapter 40a.

[0012] Through the above procedure, the packet control device 42 and communication management device 30 in the protocol conversion adapter 40a are
When a communication path is set between the protocol conversion necessity determination means 32 in the protocol conversion adapter 40a, the protocol conversion necessity determination means 3 in the packet control device 42 in the protocol conversion adapter 40a
2 sends an "inquiry" to the DT as to whether protocol conversion is required for the packet terminals 6a and 6b to communicate.
It is transmitted in packet S5. When the packet control means 31 in the communication management device 30 receives the DT packet S5, the content of the "inquiry" is transmitted to the protocol conversion necessity determination means 32.
to notify.

When the protocol conversion necessity determining means 32 determines that protocol conversion is necessary, it determines that "protocol conversion is necessary".
The packet control means 31 is requested to transmit the DT packet S6 containing the "response" content. When the packet control device 42 in the protocol conversion adapter 40a receives the DT packet S6, the communication path set up with the communication management device 30 becomes unnecessary, so it transmits the CQ packet S7 and transmits the CI packet S8, CF The communication path is disconnected by a predetermined procedure of packet S9 and CF packet S10.

When the communication path is disconnected, the packet control device 42 in the protocol conversion adapter 40a puts the protocol conversion means 422 into a state where it can be used for communication between the packet terminals 6a and 6b.
In order to set up a communication path between the packet terminal 6b and
A CR packet S11 containing the subscriber number of is transmitted to the packet switching network 1. The user data area of the CR packet S11 also includes information indicating that "protocol conversion is required" in order to enable the use of the protocol conversion means 422 present in the packet control device 42 in the protocol conversion adapter 40b. It will be done.

When the packet switching network 1 receives the CR packet S11, it transmits a CN packet S12 to the protocol conversion adapter 40b to which the packet terminal 6b is connected. At this time, the packet switching network 1 transparently transfers the information in the user data area of the CR packet S11 to the user data area of the CN packet S12 using a function originally possessed by the packet switching network 1. When the protocol conversion adapter 40b receives the CN packet S12,
Inspect the user data area in the CN packet S12,
When it recognizes that "protocol conversion is required", the protocol conversion means 422 in the packet control device 42 is enabled, and only the information indicating that "protocol conversion is required" is stored in the user data area of the CN packet S12. The CN packet S13 from which the CN is removed is transmitted to the packet terminal 6b. When the packet terminal 6b receives the CN packet S13, it transmits the CA packet S14. The protocol conversion adapter 40b converts the CA packet S14
When receiving CA packet S14, C
A packet S15 is transmitted to the packet switching network 1.

[0016] When the packet switching network 1 receives the CA packet S15, it instructs the protocol conversion adapter 40a to
C packet S16 is transmitted. Upon receiving the CC packet S16, the protocol conversion adapter 40a transmits a CC packet S17 having the same content as the CC packet S16 to the packet terminal 6a. When the packet terminal 6a receives the CC packet S17, it becomes ready to communicate with the packet terminal 6b.

By the above procedure, between the packet terminal 6a and the packet terminal 6b, the calling side packet terminal 6a, the calling side protocol conversion adapter 40a, the packet switching network 1,
A communication path is set up along the route of the called side protocol conversion adapter 40b and the called side packet terminal 6b, and
In the protocol conversion adapter 40a, the packet terminal 6a
Mutual conversion is performed between a protocol higher than the packet level of the packet terminal 6b and one standard protocol, and mutual exchange is performed between the protocol higher than the packet level of the packet terminal 6b and one standard protocol. This enables communication between the packet terminals 6a and 6b, which use different protocols above the packet level.

In the above-described procedure, when the protocol conversion necessity determining means 32 in the communication management device 30 determines that protocol conversion is not necessary, a response including "protocol conversion not required" is sent to the calling side using DT packet S6. The protocol conversion adapter 40a is notified. As a result, the calling side protocol conversion adapter 40a can make a call without notifying the called side about whether or not protocol conversion is necessary, and further without using the protocol conversion means 422 of the calling side protocol conversion adapter 40a. Calling packet terminal 6
a, the calling side protocol conversion adapter 40a, the packet switching network 1, the called side protocol conversion adapter 40b, the called side packet terminal 6b, or if there is no protocol conversion adapter on the called side, the calling side packet Communication between the packet terminal 6a and the packet terminal 6b is performed through a route including the terminal 6a, the calling side protocol conversion adapter 40a, the packet switching network 1, and the called side packet terminal 6b.

According to the above embodiment, the means related to protocol conversion is installed outside the packet switching network and packet terminals, so when adding a protocol conversion service to an existing packet switching network, the existing Since there is no need to modify central office switching equipment or packet terminals,
The present invention provides an effective means for constructing a value-added communication network that provides protocol conversion services based on packet switching networks that are already established in the market. When constructing a value-added communication network, the communication management device plays the role of a communication service center, and the protocol conversion adapter plays the role of a service usage license given to those who apply to use the service. In addition, in the above embodiment, the number of packet terminals accommodated in the packet switching network is 2, but
It goes without saying that the present invention can be practiced without being limited to this number.

[0020]

As described above, according to the present invention, a communication management device is connected and joined to a packet switching network, and a protocol conversion adapter is inserted into a subscriber line to perform communication between packet switching devices. It is possible to achieve the effect that communication is possible even between packet terminals using different protocols at a higher level than the packet level, without changing the conventional packet switching network or the internal configuration of the packet switching network.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of a packet switching communication system according to an embodiment of the present invention.

FIG. 2 is an internal configuration diagram of the protocol conversion adapter in FIG. 1;

FIG. 3 is a signal procedure diagram for explaining the operation of this embodiment.

FIG. 4 is a configuration block diagram of a conventional packet switching network.

[Explanation of symbols]

1 Packet switching network 6a, 6b Packet terminal device 30 Communication management device 31 Packet control means 32 Protocol conversion necessity determining means 40, 40a, 40b Protocol conversion adapter 42
0 Packet control means 421 Communication means 422 Protocol conversion means

Claims (1)

[Claims] Claim 1: In a packet-switched communication system for communication between packet terminals using a packet-switched network, a subscriber attribute relating to a protocol higher than the packet level of a packet terminal that has joined the packet-switched network, The above-mentioned packet switching network comprises a protocol conversion necessity determining means for determining whether protocol conversion is required between packet terminals attempting to start communication, and a packet control means operating as a packet terminal for the packet switching network. In addition to using a communication management device connected to the packet switching network, the communication management device is inserted into the subscriber line connecting the packet terminal and the packet switching network, and operates as a packet terminal for the packet switching network, and operates as a packet terminal for the packet switching network. A packet control means operating as a packet switching network and a packet terminal device that starts communication using data packets ask the above-mentioned protocol conversion necessity determination means whether or not protocol conversion is required, and further receive a response. By using a protocol conversion adapter that includes a communication means for receiving and a protocol conversion means for mutually converting a protocol higher than the packet level of the packet terminal and one standard protocol, the above-mentioned means for determining whether or not the protocol conversion is necessary can be determined. A packet switching communication system characterized in that communication is performed between a calling side packet terminal and a called side packet terminal based on the determination result.