JPH04183038A - Call setting method - Google Patents

Abstract

PURPOSE:To easily select a path by temporarily trying call termination on the reception side by using plural line when setting a call, and selecting one path to be actually connected out of call incoming paths. CONSTITUTION:A communication network is composed of communication terminals or exchanges (communication equipments) 1-6, exchanges 7-9 and connection links 10-12. In this case, the communication equipment to be the transmission side transmits a connection request specifying a called party to all or one of the connecting paths, and the communication equipment to be the reception side sets a certain time limit with the reception of the first connection request addressed to the own equipment. By making a response while selecting one the one or plural same connection requests arrived within this set time limit, the connecting path is uniquely decided between the communication equipments as the transmission side and the reception side. Thus, it is not necessary to calculate the shortest path, and the path is easily decided.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a communication network having at least two communication devices (communication terminals, exchanges, etc.) and one or more connection paths connecting them. The present invention relates to a call setting method for uniquely determining one of a plurality of connection routes when a plurality of connection routes are selectable when setting up a call between a calling side communication device and a called side communication device.

[Conventional technology]

As a conventional technique of this type, a method of broadcasting and transferring data packets in a LAN (Local Area Network) has been known.

In addition, related documents describing route selection control include "Computer Communication Network Design and Analysis JV
Written by 1jay Ahuja, translated and supervised by Shin Ikeno, Kindai Kagakusha, 19B3. 9. 1. The publication of the first edition can be mentioned.

[Problem to be solved by the invention]

In the above transfer method, there is no clear connection (logical link) between the originating and receiving terminals, communication resources cannot be secured, and it cannot be used as a call setup procedure for voice calls, etc. Furthermore, it could not be used as a call setup procedure for telephone networks or the like where broadcasting cannot be realized.

On the other hand, in a multipoint connection in which multiple terminals of an l5DN are connected in a hex, it is possible for multiple terminals to respond to one incoming call when there are multiple terminals, but these terminals are the same communication partner. is assumed to be used, and when multiple communication routes can be taken within the 15DN network,
It could not be used for call connection.

An object of the present invention is to secure communication resources and easily realize dynamic route selection within a network that has a call control procedure when there are multiple routes between originating and receiving communication devices. The purpose of the present invention is to provide a method for setting up calls that is possible.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a communication network that has at least two communication devices and one or more connection paths connecting them. The device sends a connection request specifying the other party to all or a part of the connection route, and the communication device on the receiving side sends a connection request to all or part of the connection path, and the communication device on the receiving side uses the arrival of the first connection request addressed to itself as a trigger to send a connection request. By setting a certain time limit and responding by selecting one connection request from among one or more identical connection requests that arrive within the set time limit, the communication device that is the originating side and the called side can be connected. The decision was made to uniquely determine the connection route between the communication device and the new communication device.

[Operation] In the present invention, by sending connection request information for call setup to all routes connecting the originating communication device to other communication devices, route selection as described in the above-mentioned literature is possible. Calculation of the shortest route, which is done in control, becomes unnecessary, making route determination easier.

Furthermore, in order to identify the same connection request that has arrived via a plurality of routes, the optimal route selection can be simplified by assigning a connection request identifier and transmitting the call setting information.

[Example] The present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a communication network in which an embodiment of the present invention is implemented.

In the figure, 1 to 6 are communication terminals, 7 to 9 are exchanges, and 10 to 12 are connection links.

FIG. 2 is a block diagram showing an example of the configuration of the communication terminal (for example, 1) in FIG. 1.

In FIG. 2, 51 is a connection request reception unit, 52 is an exchange interface, 53 is a processor, 54 is a memory, and 5
5 is a clock source.

FIG. 3 is an explanatory diagram of a table prepared on the memory 54 in FIG. 2.

FIG. 4 is a format diagram of a connection request signal. Here, commands are distinguished into connection request signals, response signals, and disconnection signals. The originating terminal identifier contains the physical address of the originating terminal, the destination terminal identifier contains the physical address of the destination terminal, and the connection request identifier contains the call identification number assigned to the originating terminal.

As a terminal identification number, either a logical address or a physical address can be used, but if a logical address is used, the terminal or switch needs a function to exchange logical numbers and physical numbers. Here, a case is explained in which physical addresses are used.

The operation of one embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

In FIG. 1, it is assumed that 1 is a communication terminal on the originating side and 4 is a communication terminal on the destination side. Each communication terminal manages connection request identifiers for distinguishing connection requests from users in the form of a table shown in FIG. 3 on the memory 54 shown in FIG. occurs, the unused (
A connection request identifier that is empty) is assigned, the connection request identifier is changed to being in use (blocked), and when the request disappears, the connection request identifier is returned to being unused (empty).

Here, the connection request identifier may be any information as long as it can be identified and distinguished by each exchange or communication terminal, but in FIG. 3, numbers 1-n are used here.

Communication terminal 1 sends a connection request signal to exchange 7 when setting up a call.

To be more specific, the communication terminal has a configuration as shown in FIG. In this case, the receiver receives the identification number of the communication terminal 4).

As mentioned earlier, the processor 53 manages connection request identifiers in the table format shown in FIG. Finds an "empty" identifier and assigns it to the connection request. Immediately block the assigned identifier.

The exchange interface 52 receives the destination terminal number and connection request identifier from the processor 53, creates a connection request signal as shown in FIG.
It is sent to exchange 7). It should be noted that the black-and-white signal source 55 in the communication terminal 1 in FIG. 2 is used when the terminal performs incoming call processing.

Next, the exchange 7 has 10.11 as an output link and relays the connection request signal to each link. Exchange 9, which has received the connection request signal from link 10, interprets the destination of the connection request signal and determines that the call is not directed to a terminal that it accommodates.

In that case, the connection request signal is relayed. At this time, link 1
Output to other links except 0. In this case, link 1
Relay to 2.

On the other hand, the exchange 8 that received the connection request signal from the link 11
interprets the destination of the connection request signal and finds that the call is to the terminal 4 it accommodates.

Here, the exchange 8 starts a timer (not shown) (fixed time period t). When this timer times out, it returns a disconnection signal to the same connection request signal that arrives after that time.

For the same connection request signal that arrives within the timeout, it is held until the timeout. After timeout,
Compare the data of all received connection request signals and select one of them.
A response signal is returned to the selected route, and an incoming signal is sent to the terminal 4. For the remaining connection request signals not selected, a disconnection signal is returned.

Now, the case where the connection request signal from exchange 9 arrives before the timer times out will be described below.

At this time, the exchange 8 compares the two connection request signals and finds that the source and destination terminal identifiers are the same, and the connection request identifiers are also the same. Therefore, it is determined that these two connection request signals are the same, and a response is made to either connection request signal.

Here, a case will be described in which the connection request signal from the link 11 that arrived earlier is selected. At this time, switch 9 connects link 1
Sends a disconnection signal to 2. It also responds to the link 11.

By operating as described above, one route can be selected for connection requests that arrive via multiple routes. The above control method can also be performed at the terminal 4 instead of at the exchange 8.

FIG. 5 is a block diagram showing the configuration of a communication network in which another embodiment of the present invention is implemented.

In the same figure, 13 and 14 are respectively 15 and 16 on the premises network.
communication terminal (or entity that performs call control), and 17
- 22 are connection devices between a local network and a wide area network called gateways, and 23 - 25 are wide area networks. Further, 26 and 27 are private branch exchanges.

In FIG. 5, a case will be described in which communication terminal 13 and communication terminal 14 communicate (communication terminal 13 is on the caller side).

Communication terminal 13 sends a connection request signal to communication terminal 14 to exchange 26 . Here, as described in the previous embodiment, the connection request signal is given a destination terminal identifier that clearly indicates that it is a connection request from the communication terminal 13 to the communication terminal 14, a calling terminal identifier, and a connection request identifier. Ru. Exchange machine 26
is a connection request to communication terminal 14 from the destination terminal identifier of the received connection request signal, and furthermore, communication terminal 1
W on the campus where 4 exists! We know that the gateways that can connect to 16 are 17, 18, and 19.

Next, the exchange 26 connects all of the connectable gateways (1
7, 18, 19) or a part thereof (e.g. 17.1
8), relays a connection request signal to the terminal 14. Here, we will explain the case of relaying to all gateways.

Each gateway (17, 18, 19) that receives the connection request signal from the exchange 26 connects to the corresponding wide area WI.
The connection request signal is relayed to the gateway (20, 21, 22,) of the local area network 16 via (23, 24, 25).

Next, the gateway (20, 2L
22) relays the received connection request signal to the exchange 27. Furthermore, the exchange 27 identifies the communication terminal 14 from the destination terminal identifier of the received connection request signal, and causes the communication terminal 14 to receive the connection request signal.

Thereafter, the communication terminal 14 sequentially connects to the gateways 20, 21 .
A case in which a connection request identifier is received from 22 will be explained.

When the communication terminal 14 receives the connection request signal from the gateway 20, it determines from the destination terminal identifier and connection request identifier that a new connection request has arrived, and starts a timer (fixed time period t), not shown. As described in the previous embodiment, this timer is used to hold connection request signals that arrive within the timeout and return disconnection requests for those that arrive after the timeout. .

Assume now that the connection request signal from the gateway 21 arrives within the timer timeout, and the connection request signal from the gateway 22 arrives after the timeout.

When the terminal 14 receives the connection request signal from the gateway 21, it compares it with the connection request signal that arrived from the gateway 20 and determines that it is the same connection request signal based on the destination terminal identifier, originating terminal identifier, and connection request identifier. I understand. Therefore, the connection request signal is held.

After the timer times out, the communication terminal 14 selects one connection request signal from among all the connection request signals that arrived within the timeout. Here, the one from the gateway 21 is selected.

Then, the exchange 27 sends a response signal to the gateway 21 and a disconnection signal to the gateway 20.
Send it back through.

On the other hand, in response to a connection request signal from the gateway 22 that arrives after the timeout, a disconnection signal is returned.

Gateway 21 receives the response signal from communication terminal 14
further returns a response signal to the wide area network side and performs a connection operation. The gateway 20.22 that received the disconnection signal disconnects.
Perform recovery processing.

〔Effect of the invention〕

As explained above, in the call setting according to the present invention, a call is first attempted to be received on the called side using a plurality of routes, and one route to actually connect is selected from among the received calls.
This method has the advantage of facilitating route selection and simplifying route selection when communicating between local networks via a public network or the like that performs call control.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of the configuration of a communication network in which an embodiment of the present invention is implemented, FIG. 2 is a block diagram showing details of the configuration of the communication terminal in FIG. 1, and FIG. Explanatory diagram of the table prepared on the memory in Figure 2, No. 4
The figure is a format diagram of a connection request signal, and FIG. 5 is a block diagram showing an example of the configuration of a communication network in which another embodiment of the present invention is implemented. Explanation of symbols 1-6...Communication terminal, 7-9...Switchboard, 10-1
2...Connection link, 13.14...Communication terminal, 15
゜16...Internal network, 17-22...Gateway,
23-25...Wide area network, 26.27...Private branch exchange agent Patent attorney Akira Namiki Futo 2 Figure 113 Figure WE41! l

Claims (1)

[Scope of Claims] 1) In a communication network that has at least two communication devices and one or more connection paths connecting them, the communication device that is the originating side can access all or all of the connection paths. A connection request specifying the other party is sent to some of the recipients, and the receiving communication device sets a certain time limit upon receipt of the first connection request addressed to itself.
By selecting and responding to one of one or more identical connection requests that arrive within the set time limit, the communication device that is the originating side and the communication device that is the receiving side are connected. A call setting method characterized by uniquely determining a connection route for.