Design and managing method for communication networks

Claim 2

The traffic and topology independent communications network designing system according to Claim 1, wherein said physical network topology designing means (1) designs the topology of the physical network corresponding to the topology of the logical network topology designed by said logical network topology designing means (2) such that: a number of physical transmission links accommodated in each cross-connect does not exceed a predetermined value in a network topology whose number of physical transmission links connecting cross-connects in the physical network corresponding to either a start, end, or intermediate connection point of each virtual path connection connecting start and end points of each of necessary virtual paths in the logical network is a minimum; a total number of the physical transmission links to realize all virtual path connections is a minimum when counted duplicatively corresponding to each virtual path connection; and a total length of the physical transmission links is a minimum.

Claim 3

The traffic and topology independent communications network designing system according to Claim 1, wherein corresponding to the topology of the logical network topology designed independently of the traffic condition, said logical network topology designing means (2) sets path information including an identification number and route information of each virtual path required in the logical network, sets to "0" a capacity of a path as a part of the path information, and enables an optional virtual path to be used by only assigning the capacity without selecting a route at a time of using the virtual path in actual communications.

Claim 4

The traffic and topology independent communications network designing system according to Claim 1, further comprising: long-term demand change detecting means for detecting a change in a long-term traffic demand and requesting said physical network capacity setting means (3) to redesign the capacity of the transmission line in the physical network when a change amount of the long-term demand exceeds a predetermined value.

Claim 5

The traffic and topology independent communications network designing system according to Claim 4, wherein said long-term demand change detecting means monitors a use rate of each transmission line through accommodation of virtual paths in the physical network and requests to redesign the capacity of the transmission line in the physical network when the use rate is higher than a predetermined upper limit or lower than a predetermined lower limit, that is, when the change amount of the long-term demand is other than the predetermined value.

Claim 6

The traffic and topology independent communications network designing system according to Claim 1, further comprising: actual traffic demand change detecting means for detecting a fluctuation in an actual traffic demand and requesting said logical network capacity setting means (4) to redesign the capacity of virtual paths in the logical network when a fluctuation amount of the actual traffic demand exceeds a predetermined value.

Claim 7

The traffic and topology independent communications network designing system according to Claim 6, wherein said actual traffic demand fluctuation detecting means monitors a lost-call rate, a discarded-cell rate, and a cell delay time in the physical network through accommodation of virtual paths in the logical network and requests to redesign the capacity of the virtual path in the logical network when the lost-call rate, the discarded-cell rate, or the cell delay time is higher than a predetermined upper limit, that is, when the fluctuation amount of the actual traffic demand exceeds the predetermined value.

Claim 8

A network design management center for designing a logical network for use in a communications network having a physical network and a logical network established among a plurality of nodes, comprising: a first signal processing means for receiving a traffic condition of the communications network from one of the nodes in the communications network; circuit control means for controlling a design change of a capacity of a virtual path based on traffic information and a present capacity of the virtual path in the logical network; logical network capacity setting means for setting the capacity of the virtual path forming part of the logical network and changing a design of the capacity of the virtual path according to a virtual path capacity change request from said circuit control means; and a second signal processing means for outputting to the node a virtual path capacity design change instruction output from said logical network capacity setting means.

Claim 9

The network design management center according to Claim 8, wherein said circuit control means comprises: comparing means for comparing the traffic information from the node with the present capacity of the virtual path; determining means for determining whether or not a redesigning should be performed based on an output of said comparing means and a redesign determination criterion; and redesigning request means for requesting according to an output of said determining means said logical network capacity setting means to change a capacity design of the virtual path of the logical network.

Claim 10

The network design management center according to Claim 8, further comprising: actual traffic demand change detecting means for detecting a fluctuation in an actual traffic demand and requesting said logical network capacity setting means (4) to redesign the capacity of virtual paths in the logical network when a fluctuation amount of the actual traffic demand exceeds a predetermined value.

Claim 11

The network design management center according to Claim 10, further comprising: said actual traffic demand fluctuation detecting means monitors a lost-call rate, a discarded-cell rate, and a cell delay time in the physical network through accommodation of virtual paths in the logical network and requests to redesign the capacity of the virtual path in the logical network when the lost-call rate, the discarded-cell rate, or the cell delay time is higher than a predetermined upper limit, that is, when the fluctuation amount of the actual traffic demand exceeds the predetermined value.

Claim 12

A communications node for use in a communications network having a physical network and a logical network established among a plurality of node, comprising: storing means for storing corresponding to a transmission line in the physical network, a band capacity of each virtual path in the logical network passing through the transmission line in the physical network; and call acceptability determining means for determining acceptability of a communication call from a terminal in a range of the band capacity of the virtual path of the transmission line of the physical network determined for a communication destination requested by a connected terminal, wherein said band capacity stored in said storing means is changed when a virtual path band capacity change notification is received externally.

Claim 13

The communications node according to Claim 12, wherein said virtual path band capacity change notification received by the communications node is issued by said network design managing center for designing the logical network.

Claim 14

A network design managing center for designing a physical network for use in a communications network having a physical network and a logical network established among a plurality of nodes, comprising: a first signal processing unit for receiving traffic information of the communications network; circuit control means for controlling a capacity design change of a transmission line of the physical network based on the traffic information and a present capacity of the physical network; and physical network capacity setting means for setting the capacity of the physical transmission line forming the physical network and changing a capacity design of the transmission line according to a physical transmission line capacity change request from said circuit control means.

Claim 15

The network design managing center according to Claim 14, further comprising: long-term demand change detecting means for detecting a change in a long-term traffic demand and requesting said physical network capacity setting means (3) to redesign the capacity of the transmission line in the physical network when a change amount of the long-term demand exceeds a predetermined value.

Claim 16

The network designing managing center according to Claim 15, wherein said long-term demand change detecting means monitors a use rate of each transmission line through accommodation of virtual paths in the physical network and requests to redesign the capacity of the transmission line in the physical network when the use rate is higher than a predetermined upper limit or lower than a predetermined lower limit, that is, when the change amount of the long-term demand is other than the predetermined value.

Claim 17

A communications network managing system in a communications network having a physical network and a logical network with topologies and capacities of the physical network and the logical network independently designed, wherein each node in the communications network comprises: band managing means for managing a band of a physical transmission link from a present node to an adjacent node in the physical network after dividing the band into a reserved area to be assigned to a high-priority virtual path having a high-priority communication among a plurality of virtual paths through which communications are performed through a physical transmission link in the logical network, and a shared band to be used regardless of priority of the communications; and communications path connection request acceptability determining means (6) for determining acceptability of a connection request for a communications path starting from a present node only in the shared band when the connection request is related to a low-priority communication and both in the shared band and the reserved band when the connection request is related to a high-priority communication.

Claim 18

The communications network managing system according to Claim 17, further comprising: detour path candidate registering means (7) for preliminarily registering a plurality of communications path candidates applicable to the connection request and providing the communications path candidates for said communications path connection request acceptability determining means (6) at a determination of the acceptability in response to a communications path connection request.

Claim 19

The communications network managing system according to Claim 18, wherein said detour path candidate registering means (7) unconditionally selects and registers a predetermined number of communications paths as detour path candidates applicable to a communications path condition indicated by the connection request from all communications paths from start-point nodes to end-point nodes of the communications paths. said communications path connection request acceptability determining means (6) unconditionally selects one communications path candidate from the detour path candidates, determines the acceptability in response to the communications path connection request, allocates to a selected communications path a band indicated by the connection request if the request is acceptable, and repeats determining the acceptability of another detour path candidate after selecting it from the detour path candidates registered in said detour path candidate registering means (7).

Claim 20

The communications network managing system according to Claim 18, wherein said detour path candidate registering means (7) sequentially registers the predetermined number of communications paths from shortest to longest total length of the physical transmission link corresponding to the communications path as detour path candidates applicable to a communications path condition indicated by the communications path connection request among all communications paths from start-point nodes to end-point nodes of the communications paths; said communications path connection request acceptability determining means (6) selects a detour path candidate having a shortest total length of the physical transmission link from the detour path candidates, determines the acceptability in response to the connection request, allocates to a selected communications path a band indicated by the connection request if the request is acceptable, and repeats determining the acceptability of detour path candidate in response to the communications path connection request after selecting from shortest to longest total length of the physical transmission link the detour path candidate from the detour path candidates registered in said detour path candidate registering means (7).

Claim 21

The communications network managing system according to Claim 18, wherein said detour path candidate registering means (7) sequentially registers the predetermined number of communications paths from smallest to largest number of the physical transmission links as detour path candidates applicable to a communications path condition indicated by the communications path connection request among all communications paths from start-point nodes to end-point nodes of the communications paths; said communications path connection request acceptability determining means (6) selects a communications path having a smallest total number of the physical transmission links from the detour path candidates, determines the acceptability in response to the connection request, allocates to a selected detour path candidate a band indicated by the connection request if the request is acceptable, and repeats determining the acceptability of detour path candidate after selecting from the smallest total number of the physical transmission links the detour path candidate from the detour path candidates registered in said detour path candidate registering means (7).

Claim 22

A communications network managing system in a communications network having a physical network and a logical network with topologies and capacities of the physical network and the logical network independently designed, comprising: information packet sending means (8), provided in an end-point node of the communications path set as passing through optional nodes among a plurality of nodes in the communications network, for sending through a communications path an information packet in which spare capacity information about the communications path is sent toward a start-point node of the communications path; spare capacity information adding means (9), provided in each relay node in the communications path, for adding spare capacity information in the communications path toward an adjacent node to the information packet received from the adjacent node, and sending it the information back to a start-point node through the communications path; and capacity change determining means (10), provided in the start-point node in the communications path, for determining based on contents of the information packet acceptability of a communication capacity change request for the communications path, wherein a communications path satisfying the change requests is selected, in response to the communication capacity change request, from a plurality of communications paths between the start-point nodes and the end-point nodes according to a determination result of said capacity change determining means (10).

Claim 23

The communications network managing system according to Claim 22, wherein said capacity change determining means (10) determines the acceptability of the communication capacity change request based on the contents of the information packet received at a plurality of points.

Claim 24

The communications network managing system according to Claim 23, wherein said plurality of points refer to two points.

Claim 25

The communications network managing system according to Claim 24, wherein said capacity change determining means (10) determines the acceptability of the communications capacity change request through a linear prediction based on the contents of the information packet received at the two points.

Claim 26

The communications network managing system according to Claim 23, wherein said plurality of points refers to three or more points; and said capacity change determining means (10) determines the acceptability of the communication capacity change request based on existing change patterns of spare capacity in the communications path.

Claim 27

The communications network managing system according to Claim 26, wherein said capacity change determining means (10) determines the acceptability of the communication capacity change request based on the existing change pattern through a neural network.

Claim 28

A communications network managing system in a communications network having a physical network and a logical network with topologies and capacities of the physical network and the logical network independently designed, comprising: information packet sending means, provided in an end-point node of the communications path not completely included in another communications path among a plurality of communications paths set as passing through optional nodes in a plurality of nodes in the communications network, for sending through a communications path an information packet in which spare capacity information about the communications path is sent toward a start-point node of the communications path; spare capacity information adding means, provided in each relay node in the communications path not completely included in another communications path, for adding spare capacity information in the communications path toward an adjacent node to the information packet received from the adjacent node, and sending it the information back to a start-point node through the communications path; and capacity change determining means, provided in the start-point node in the communications path not completely included in another communications path, and in the start-point node of the communications path completely included in the communications path not completely included in another communications path among the relay nodes, for determining acceptability of a communication capacity change request for the communications path for which a present node is a start point, wherein a communications path satisfying the change requests is selected, in response to the communication capacity change request, from a plurality of communications paths between the start-point nodes and the end-point nodes according to a determination result of said capacity change determining means.