JPH09191322A - Data exchange route selection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent line congestion by devising load distribution in a data exchange network and effective utilization of bypass lines with respect to the route selection system in the network. SOLUTION: Each station of the data exchange network is provided with a delay time measurement means 1 measuring a delay time of each route, a line utilizing rate measurement means 2 measuring a line operating rate for each route and a delay allowable value setting means 3 setting an allowable delay time between each terminal equipment under the control and an opposite terminal equipment. Then a route satisfying an allowable delay time of the terminal equipment among plural routes is selected for each communication and a route with a lower line operating rate is selected among the selected routes to average the line operating rate while keeping the response of the terminal equipment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route selection method in a data exchange network, and more particularly to a data exchange system for selecting a communication route based on a trunk line utilization rate, an intra-network delay time, and a response priority of a system. The present invention relates to a route selection method.

[0002] In a data exchange system, when communication is performed between terminals, between the exchanges to which each terminal belongs,
By establishing a route on the network and connecting to each other, they communicate with each other.

In this case, the selection of the route connecting the exchanges in the network enables load distribution in the network, effective use of the bypass line, and prevention of line congestion. It is necessary to be.

[0004]

2. Description of the Related Art As a route selection system in a conventional data exchange network, a system in which one routing table is allocated to one terminal is generally used. That is, the switching center to which a terminal belongs has a routing table assigned to each terminal and defining a route to the destination terminal, and the route is selected according to this routing table to transfer data. .

[0005]

In the method of fixedly allocating one routing table for one terminal, when communication is concentrated on the trunk line of one section in the network, when the communication volume of other section is small. , Considering the network as a whole, it is in a state where the load is not distributed.

If the load distribution is insufficient, the waiting time varies depending on the base of the communication partner. That is, the response time varies depending on the communication partner, and the communication in the network is performed in an unbalanced state.

In the data communication system, along with the increase in communication volume in recent years, it is required to improve communication efficiency, and it is necessary to shorten the response time as much as possible. If there are long sections, there is a risk that the operation of the system will be hindered.

Further, when the amount of communication exceeds the capacity of some of the trunk lines, communication restriction (congestion) may occur due to some of the sections, and therefore only some of the sections are Therefore, communication will be hindered in the entire network.

The present invention is intended to solve the problems of the prior art as described above, and in a data exchange network, it is possible to balance the load in the network and to effectively use a bypass line. Further, it is an object of the present invention to provide a data exchange route selection method capable of selecting a route connecting between exchange stations so as to prevent line congestion.

[0010]

According to the method of the present invention,
Each system connected to the data exchange network is provided with a threshold of an allowable delay time, and the route is selected in consideration of the delay time, the line usage rate of the relay line, and the communication data amount.

Basically, a route with a small amount of data is selected for communication, but depending on the system, there is a limit on the allowable delay time, so communication is possible within that delay time, and communication is possible. Select a route with a small amount to communicate.

For a system where the response is the most important, the "response" priority can be set so that the route with the smallest delay time is selected for communication.

By the above means, it becomes possible to balance the load on the relay lines of the entire network, smooth the response time, and effectively use the lines. Specific means for solving the above-mentioned problems will be listed below.

FIG. 1 shows the basic configuration of the present invention, and shows the configuration of an exchange to which the present invention is applied.

(1) In a system in which a plurality of stations in a network can communicate with each other by a plurality of data transfer routes in the network, each station has a delay time measuring means 1 for measuring a delay time for each route, and each station. In addition to the line usage rate measuring means 2 for measuring the line usage rate, the delay allowable value setting means 3 for setting the allowable value of the delay time with the partner terminal is provided for each subordinate terminal. Then, for each communication, the route that satisfies the allowable delay time of the terminal is selected from among multiple routes, and the route with low line utilization rate is selected from among the selected routes to maintain the response of the terminal. While averaging line usage.

(2) In the case of (1), when the number of relay stages of the data transfer route is 2 or more, the one having a low line utilization rate is selected from all the relay routes on this data transfer route.

(3) In a system in which a plurality of stations in a network can communicate with each other by a plurality of data transfer routes in this network, each station has a delay time measuring means 1 for measuring a delay time for each route, and a route on the route. And a buffer amount measuring means 4 for measuring the in-system communication buffer amount of each node, and a delay allowable value setting means 3 for setting an allowable value of the delay time with the partner terminal for each subordinate terminal. Then, for each communication, a route that satisfies the allowable value of the delay time of the terminal is selected from among multiple routes, and a route with a small amount of intra-system communication buffer of the node on the route is selected from among the selected routes. , Average the line utilization while maintaining the response of the terminal.

(4) In the case of (3), if the number of relay stages of the data transfer route is 2 or more, all nodes on the data transfer route having a small intra-system communication buffer amount are selected.

(5) In any one of (1) to (5), if the occurrence of congestion is determined by the line usage rate or the communication buffer amount in the system, the occurrence of congestion is determined. Select the route excluding the data transfer route.

(6) In any one of (1) to (5), a terminal having a higher response priority class that is set selects a data transfer route having a smaller delay time.

(7) In any one of (1) to (5), the terminal with the lowest data priority has the lowest line utilization in the network or the node intra-system communication buffer. Routing is performed using a data transfer route with a small amount.

By performing the data transfer according to the method of the present invention, it is possible to distribute the load on the entire line and the exchange in the network without causing the inconvenience caused by the delay time, and smooth the response time and the line. Can be effectively used.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 2 shows the configuration of a network according to an embodiment of the present invention. FIG.
3 is a flowchart showing a route selection method of the present invention. Hereinafter, a route selection method for communication between the terminal A and the terminal B in the network shown in FIG. 2 will be described.

(1) In station a accommodating terminal A,
The line utilization rate of each trunk line (-) is measured at fixed time intervals, and the measurement results are collected and recorded. Instead of the line usage rate, the amount of staying data in the exchange, that is, the amount of communication buffer in the system can be used.

(2) If there is a congested trunk line as a result of the data collection in (1), it is excluded from the routes of the routing selection candidates.

(3) At the same time as (1), station a accommodating terminal A measures the delay time in the network of the route to reach terminal B at a constant time cycle, and shows the result. Collected and recorded. In FIG. 2, there are three routes from terminal A to terminal B :, →, →.

(4) The allowable delay time of the system accommodated in each exchange is set in each exchange. For the terminal A, the set allowable delay time is compared with the intra-network delay time of each route collected in (3), and only routes that can be routed within the allowable delay time are left as selected routes.

(5) In each exchange, it is possible to set in advance whether or not the response is most important for the communication of the accommodated system.
In the case of “response priority”, the route with the lowest line usage rate (or the amount of data stored in the exchange) selected in (4) is selected for communication.

In this case, for routes that pass through two or more stations (in FIG. 2, two routes, → and →),
For all trunk lines through which data passes, it is necessary to reduce the line utilization rate or the amount of accumulated data in the exchange.
In this case, for example, a method of comparing with an average value of the line usage rate of the trunk line can be adopted.

(6) When the data priority is determined for each terminal, for the data of the terminal having the low data priority, the data transfer route having the lowest transmission efficiency in the network, that is, the line. The routing is performed using the data transfer route that has the lowest usage rate or the node has a small intra-system communication buffer amount.

[0031]

As described above, by performing data transfer according to the method of the present invention, it is possible to perform load distribution on the entire lines and exchanges in the network without the inconvenience caused by the delay time. Become.

Further, when the network is in a normal state, it is possible to effectively use the detour line according to the communication state.

Further, even if the amount of communication increases in a part of the network, the line congestion does not occur immediately, and the route is selected by selecting an empty line. Therefore, the amount of data in the part of the network increases. Route congestion is less likely to occur because of just one.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention.

FIG. 2 is a diagram showing a network configuration according to an embodiment of the present invention.

FIG. 3 is a flowchart showing a route selection method of the present invention.

[Explanation of symbols]

 1 delay time measuring means 2 line utilization measuring means 3 delay allowable value setting means 4 buffer amount measuring means

Claims (7)

[Claims] 1. In a system in which a plurality of stations in a network can communicate with each other by a plurality of data transfer routes in the network, each station has a delay time measuring means for measuring a delay time for each route and a line for each route. In addition to the line usage rate measuring means for measuring the usage rate, the delay tolerance value setting means for setting the tolerance value of the delay time with the partner terminal is provided for each subordinate terminal, and multiple routes are available for each communication. Select a route that satisfies the allowable delay time of the terminal from among the selected routes and select a route with a low line utilization rate from among the selected routes to maintain the terminal response and average the line utilization rate. Data exchange route selection method characterized by conversion. 2. The data exchange route selection method according to claim 1, wherein when the number of relay stages of the data transfer route is 2 or more, one having a low line utilization rate is selected among all the relay routes on the data transfer route. A data exchange route selection method characterized by: 3. In a system in which a plurality of stations in a network can communicate with each other by a plurality of data transfer routes in the network, each station has a delay time measuring means for measuring a delay time for each route, and each station on the route. With a buffer amount measuring means for measuring the communication buffer amount in the system of the node,
A delay allowance value setting means for setting an allowance value for the delay time with the partner terminal is provided for each subordinate terminal, and a route that satisfies the allowance value for the delay time of the terminal is selected from a plurality of routes for each communication. Along with this, data that is characterized by averaging the line usage rate while maintaining the response of the terminal by selecting one of the selected routes that has a small intra-system communication buffer amount of the node on the route. Exchange route selection method. 4. The data exchange route selection method according to claim 3, wherein, when the number of relay stages of the data transfer route is 2 or more, all nodes on the data transfer route have a small intra-system communication buffer amount. A data exchange route selection method characterized by selecting. 5. The data exchange route selection method according to any one of claims 1 to 4, wherein the occurrence of congestion is determined when the occurrence of congestion is determined by a line usage rate or an intra-system communication buffer amount. A data exchange route selection method characterized in that a route is selected by excluding a data transfer route determined to be. 6. The data exchange route selection method according to claim 1, wherein a terminal having a response priority class set has a higher response priority class. A data exchange route selection method characterized by selecting a data transfer route with a small delay time. 7. The data exchange route selection method according to claim 1, wherein a terminal having a low data priority has the lowest line usage rate in the network or a node system. A data exchange route selection method characterized by performing routing using a data transfer route with a small amount of internal communication buffer.