JP2500618B2 - Network inter-office design method - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an economical communication network design method.

[0002]

2. Description of the Related Art A conventional economical design method for a communication network is, for example, an invention "economy design method" disclosed in Japanese Patent Laid-Open No. 1-251835. This is an economical design method, in which an economical initial network configuration is obtained based on the inter-station distance information and the inter-station traffic volume information, and the inter-station links are re-established based on this initial network configuration to further improve the economic network. By finding the configuration, it is possible to design economically the high-speed digital line network applied to multimedia communication.

In addition, in order to optimally update the existing network, the vacant portion of the existing transmission link is searched for by brute force.

[0004]

However, such a conventional network economic design method is premised on a new network introduction design, and will cope with optimal reconfiguration accompanying the increase in demand, which will be the mainstream of network design in the future. There is a problem that can not be done.

Further, in order to allocate a large number of additional paths as routes to the unused portion of the existing transmission link, a method of brute force checking the order of the added paths and the route is adopted.
Design efficiency is poor because a huge amount of calculation time is required.

The present invention has been made by paying attention to the problems of such conventional techniques, and based on the increased demands of traffic and data paths for already operating networks, transmission links and the like are It is an object of the present invention to provide an economical design method capable of efficiently reconfiguring a network efficiently by effectively utilizing existing resources.

[0007]

The gist of the present invention for achieving the above object lies in the following two items.

[1] Cross-connect devices for multiplexing the paths of the transmission links and changing the connection of the paths passing through the transmission links are installed in a plurality of stations, and the cross-connect devices are connected by the transmission links. In the inter-station design method for a configured communication network, the existing link free space calculation unit (1) comprises an existing link free space calculation unit (1) and an additional path allocation unit (2).
Creates the existing transmission link free information by sorting the number of paths that can be accommodated when the speed of the path is specified for each existing transmission link according to the speed of the path.

The additional path allocation unit (2) includes a path priority determination unit (101), a priority-based path extraction unit (102), a path shortest route search unit (103), a path allocation unit (104), and a priority end. It is composed of a determination unit (105) and an existing link free space recalculation unit (106).

The path priority determining section (101) prioritizes all the additional paths according to the speed of the path as the attribute of the path, and rearranges them in order from the high order to the low order.

The priority-based path extraction unit (102) collectively extracts paths having the same priority in order from the highest priority one.

A path shortest route search unit (103) extracts the transmission links assigned to the empty parts by the paths extracted by the priority-based path extraction unit (102) and collects the extracted paths by origination / destination station. , Determining the shortest path using the free portion of the transmission link for the aggregated path.

The path allocating unit (104) passes the transmission link through which the path found by the shortest path searching unit (103) among the paths extracted by the priority-based path extracting unit (102) passes. In the order of the smallest number, if the ranks are the same, the paths are rearranged in the order of the shortest total path length, and the paths are assigned in order from the highest order path to the number of allocatable paths.

The priority end judging section (105) checks whether or not there is a next priority path when there is the unused free portion of the transmission link.

Existing link free space recalculation unit (106)
Recalculates the unused information of the transmission link when a path of the next priority remains.

[2] Existing link free space calculation unit (1)
In addition to the network inter-station designing method, which is composed of an additional path allocating unit (2) and an additional path allocating unit (2), a new method is provided for the path that could not be accommodated in the existing transmission link at a stage subsequent to the additional path allocating unit (2). A new network design unit (3) for setting the transmission link and obtaining the path of the path and the speed of the new transmission link
The inter-network station designing method according to claim 1, further comprising:

[0017]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the inter-network station designing method of the present invention.

It is composed of an existing link free space calculation unit 1 and an additional path allocation unit 2.

The existing link free space calculation unit 1 sorts the number of paths that can be accommodated when the speed of the path is specified for each existing transmission link by the speed of the existing path. Create availability information.

In FIG. 1, the existing link free capacity calculation unit 1 specifies the speed of each additional path for each existing transmission link, and obtains the number of paths that can accommodate the same speed path in the unused empty portion. Calculate unused unused information on transmission link. The unused free information takes the form of a list of the number of single speed accommodable paths for each speed. The additional path allocating unit 2 finds a route by an unused portion based on the unused free information of the transmission link calculated by the existing link free space calculating unit 1 and allocates the additional path to the existing transmission link.

This part will be described in detail with reference to FIG.

The additional path allocation unit 2 is a path priority determination unit 1
01, a path extraction unit for each priority 102, a shortest path search unit 103, a path allocation unit 104, a priority end determination unit 105, and an existing link free space recalculation unit 106.

The path priority determining unit 101 prioritizes all the additional paths according to the speed of the path as an attribute of the path, and rearranges them in order from the high order to the low order.

The priority-based path extraction unit 102 collectively extracts paths having the same priority in order from the highest priority one.

The path shortest route search unit 103 extracts the transmission links to which the paths extracted by the priority-based path extraction unit 102 are assigned to the vacant parts, collects the extracted paths according to originating and destination stations, and collects them. The shortest path using the empty portion of the transmission link for the determined path.

The path allocation unit 104 includes a path shortest route search unit 10 among the paths extracted by the priority-based path extraction unit 102.
For the paths for which paths have been found in 3, the paths with the fewest number of transmission links that pass through are sorted in order, and if they have the same rank, they are rearranged in the order of the paths with the shortest total path length, and all the paths are sorted in order from the highest rank. Allocate as many routes as the number of allocatable paths.

The priority end determination unit 105 checks whether or not there is a path with the next priority when there is the unused free portion of the transmission link.

The existing link free space recalculation unit 106 recalculates the unused information of the transmission link when a path having the next priority remains.

Finally, the process returns to the priority-based path extraction unit 102, and the processes after the path shortest path search unit 103 are repeated for the next priority path.

FIG. 3 is a chart showing a second embodiment of the present invention.

In addition to the above network inter-station design method comprising the existing link free capacity calculation unit (1) and the additional path allocation unit (2), the existing transmission is provided at the next stage of the additional path allocation unit (2). A new network design unit (3) is added to set a new transmission link for the path that could not be accommodated in the link and obtain the path of the path and the speed of the new transmission link.

In the first embodiment, the process returns to the priority-based path extraction unit 102, and the processes of the path shortest path search unit 103 and subsequent processes are repeated for the next priority path. Returning to this, finally, the new network designing unit 3 processes the additional paths that have not been allocated yet. A path group is created by bundling paths that match at both end stations, setting an initial route that directly connects both end stations for each path group, and determining the transmission link usage efficiency from the line cost and usage rate for each new transmission link, resulting in poor efficiency. The transmission links are selected in order, and the combination of the alternative routes of the path group in the designated transmission link that minimizes the line cost of the entire network is obtained. The optimization process is repeated until the cost of the entire network is reduced.

[0033]

As described above, according to the present invention, in the inter-station design of the network that is already in operation, the additional paths are rearranged by the attribute of the path, and the unused free information of the existing link is held and updated. By allocating the additional path to the existing link, it is possible to effectively use the existing resource by allocating the additional path to the empty portion of the existing link.
Also, when allocating additional paths to existing transmission links, it is possible to collectively find path routes for paths classified by priority from unused unused information according to path attributes, and search for routes in a brute force manner. It is possible to reduce the number of times of route search as compared with, and it is possible to realize an inter-station design method for processing in a shorter time.

[Brief description of drawings]

FIG. 1 is a chart showing an embodiment of a network designing method of the present invention.

FIG. 2 is a flowchart of an additional path allocation unit.

FIG. 3 is a chart showing a second embodiment of the network designing method of the present invention.

[Explanation of symbols]

 1 Existing Link Free Capacity Calculation Unit 2 Additional Path Allocation Unit 3 New Network Design Unit 101 Path Priority Determination Unit 102 Priority-Specific Path Extraction Unit 103 Path Shortest Route Search Unit 104 Path Allocation Unit 105 Priority End Determination Unit 106 Existing Link Vacant Capacity recalculation unit 107 Priority end determination unit

Claims (2)

(57) [Claims] 1. A configuration in which a cross-connect device for multiplexing a path of a transmission link and changing a connection of a path passing through the transmission link is installed in each of a plurality of stations, and the cross-connect devices are connected by a transmission link. In the inter-network station design method of the communication network, the existing link free space calculation unit and the additional path allocation unit are configured, and the existing link free space calculation unit is configured to perform the speed of the path for each existing transmission link. Existing transmission link availability information is created by organizing the number of paths that can be accommodated by specifying the path speed, and the additional path allocation unit includes a path priority determination unit and a priority-based path extraction unit. The path shortest route search unit, the path allocation unit, the priority end determination unit, and the existing link free space recalculation unit are included. According to the speed of the path as an attribute, all the additional paths are given the priorities and rearranged in order from high-ranked ones to low-ranked ones. The paths having the same priority are collectively extracted, and the path shortest path search unit extracts the transmission link that is assigned to the empty portion from the paths extracted by the priority-based path extraction unit, and extracts the extracted paths. Summarizing by origin and destination stations, obtaining the shortest path using the empty portion of the transmission link for the collected paths, the path allocation unit, the path shortest among the paths extracted by the priority-based path extraction unit Regarding the paths whose paths are found by the path searching unit, the paths with the smallest number of the transmission links passing through are arranged in order, and when the paths are in the same order, the paths are rearranged in the order of the path with the shortest total path length, Routes are collectively assigned in order from the high-order path to the number of allocatable paths, and the priority end determination unit determines the next priority path when there is a free portion of the transmission link. A method for designing between network stations, characterized in that the existing link free space recalculation unit recalculates the unused space information of the transmission link when a path of the next priority remains. 2. A new transmission link is set for the path that could not be accommodated in the existing transmission link, and the path of the path and the speed of the new transmission link are calculated next to the additional path allocation unit. The inter-network station designing method according to claim 1, further comprising a network designing unit.