JPH02202138A - Network system route selecting system - Google Patents

Abstract

PURPOSE:To improve data transfer efficiency by designating a bridge with the minimum quantity of traffic as the bridge to perform the data transfer according to the connection request command of the bridge by referring to allocation information stored in a memory means. CONSTITUTION:The bridges 51-53 execute the data transfer according to the allocation information stored in the memory means 51a-53a provided at each bridge, respectively. Also, it is possible to designate the bridge with the minimum quantity of traffic as the one to perform the data transfer for a new communication request by using the allocation information. Therefore, the allocation of a route can be performed even when no transmission information is generated by a station in a network, and also, the data transfer can be allocated to each of the bridges 51-53 uniformly. In such a way, it is possible to efficiently execute the data transfer between the networks without attaching a specific function on the station.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a route selection method for a network system, and particularly to a route selection method in a local area network (LAN).

(Prior Art) Conventionally, when there are multiple routes (bridges) connecting segments of a LAN, a source routing method or a spanning tree algorithm method is used to select the route. Ta.

In source routing, routing is performed by stations in the LAN sending commands containing routing information.

Therefore, when this method is used, a function for generating route information must be added to each station, which has the disadvantage of complicating the configuration of the station.

On the other hand, in the Spanning Tree φ algorithm, routes are selected by exchanging information between bridges that connect networks, so there is no need to add a function to generate route information to the stage engine. however,
In this spanning tree algorithm method, only one bridge among multiple bridges is used and the other bridges are not used at all, so the burden on the working bridges assigned to the route is large and sufficient data transfer efficiency is not achieved. There are disadvantages that cannot be obtained.

(Problem E to be solved by the invention) This invention was made in view of the above-mentioned circumstances, and in the past, the configuration of the station was complicated due to the selection of the transfer route, and the data transfer efficiency was reduced. It is an object of the present invention to provide a route selection method for a network system that can obtain sufficient data transfer efficiency without providing special functions to stations.

[Structure of the Invention (Means for Solving the Problems) The present invention is a network system in which data is transferred between networks by a master bridge and a slave bridge connected in parallel between a first and a second network, Each of the master bridge and slave bridge has memory means for storing allocation information representing the communication allocation state of each bridge, and refers to the allocation information stored in this memory means, and stores only data corresponding to the allocation information. and transfer means for transferring the connection request command, and when the master bridge receives the connection request command from the network, it refers to the allocation information stored in the memory means and assigns the bridge with the least amount of traffic to the connection request command. The present invention is characterized by comprising a bridge designating means for designating a bridge for performing data transfer according to the above, and a means for updating allocation information of the memory means based on the contents designated by the bridge designating means.

(Function) In the route selection method of this network system,
Each bridge performs data transfer according to the allocation information stored in its respective memory means. Furthermore, by using the assignment information, the bridge with the smallest amount of traffic can be designated as the bridge for data transfer in response to a new communication request. Therefore, it is possible to allocate routes without stations in the network generating transfer information, and it is also possible to allocate data transfer uniformly to each bridge.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a system configuration for realizing a route selection method according to an embodiment of the present invention. Stations 21.22 are connected to the loop type LAN 11. Stations 41.42 are connected to the bus type LAN 31. A master bridge 51 and slave bridges 52 and 53 are connected in parallel between the loop type LAN 11 and the bus type LAN 31.

These bridges include memories 51a and 52, respectively.
a.

53a is provided. These memories 51a to 53a
A management table is stored in which information representing the communication allocation status of each bridge is registered.

FIG. 2 shows an example of the management table. This management table includes a logical connection number that indicates which channel is assigned to communication, a physical address 11 that indicates a station in network tt that is communicating, and a physical address that indicates a station in network 31 that is communicating. 2. Bridge number indicating the bridge being used. For example, if data transfer between station 21 of network 11 and station 41 of network 31 is performed on the seventh channel, the logical connection number is "7" and the physical address 1 is r2100000 J, as shown in the figure. The physical address 2 becomes r4100000 J and the bridge number becomes "52".

Master bridge 51. and slave bridge 52.
53 are memories 5La, 52a, 53, respectively.
Refer to the management table of a and execute only the data transfer corresponding to the assignment. In addition, master bridge 5
1 has a function of specifying the bridge with the least amount of traffic as the bridge for data transfer in response to a new communication request based on the contents of the management table, and writes the contents of the management table of each memory 51a to 53a according to the specified contents. It has the ability to change.

Next, the route selection operation in this network system will be explained. When station 21 of network 11 performs data transfer with station 42 of network 41, station 21 first sends out a logical connection connection request packet. This connection request packet is received by the master bridge 51. The master bridge 51 refers to the bridge numbers in the management table of the memory 51a and selects the bridge with the least number of logical connections.

Then, the master bridge 51 adds the number of the selected bridge, the logical connection number, the physical address 1 of station 2, and the physical address 2 of station 42 to the management table of each memory 51a to 53a. When the update of the management table is completed in this way, the master bridge 51 transfers the connection request packet to the network 31.

In the slave bridges 52 and 53, data is transferred only for logical connections registered in the management table, so the connection request packet is ignored.

Data packets other than connection request packets are transferred by the bridge corresponding to the data transfer based on the logical connection number and bridge number in the management table, and other bridges ignore the packets.

However, if the response packet to the connection request packet is sent from the same network, there is no need to transfer data via the bridge, so the master bridge 51
Alternatively, the data corresponding to the logical connection 3 is deleted from the management table by the bridge corresponding to the data transfer.

Furthermore, when a disconnection completion packet is sent from a station, the bridge that received the packet deletes data corresponding to that logical connection from the management table.

The contents of management tables are exchanged between the bridges 51 to 53, and inquiries are periodically made to verify whether the other bridges are operating normally. If there is no response to the arrangement, or if there is a response indicating "abnormality," the bridge number in the management table is rewritten by the bridge that made the inquiry to the number of a normal bridge.

In this way, in this route selection method, each bridge executes data transfer according to the allocation information stored in its own memory. Furthermore, by using the assignment information, the bridge with the smallest amount of traffic is designated as the bridge for data transfer in response to a new communication request. Therefore, it is possible to allocate routes without stations in the network generating transfer information, and it is also possible to allocate data transfer uniformly to each bridge.

[Effects of the Invention] As described above, according to the present invention, it is possible to efficiently transfer data between networks without adding special functions to the stage engine.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing an example of a management table provided in each bridge of the system shown in FIG. 11...Loop type LAN, 21.22.41.42
...Station, 31...Bus type LAN, 51.
...Master bridge, 52.53...Slave bridge, 51a to 53a...Memory. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] A network system in which data is transferred between networks by a master bridge and a slave bridge connected in parallel between first and second networks, wherein each of the master bridge and slave bridge The master bridge comprises a memory means for storing allocation information representing a communication allocation state, and a transfer means for referring to the allocation information stored in the memory means and transferring only data corresponding to the allocation information. When receiving a connection request command from the network, refers to the allocation information stored in the memory means and designates the bridge with the least amount of traffic as the bridge for data transfer according to the connection request command. A route selection method for a network system, comprising: a bridge specifying means; and a means for updating allocation information in the memory means based on contents specified by the bridge specifying means.