EP0372270A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Adaptive routing control method
Assignee: NTT Inc
•
Filing: 1989-11-15
•
Granted: —
•
Expires: 2009-11-15
Abstract
Abstract I In a telecommunications network in which a plurality of switching nodes (N1 to N6) are interconnected via links (L12, L23) each composed of a plurality of trunks and are each connected to a network control center (NC) via a control signal link (C1 to C6), the network control center determines for each switching node a predetermined number of alternate routes for each first route on the basis of traffic data in the telecommmun- ciations network and supplies them as a set of available alternate routes to the switching node. The switching node assigns one or more of the available alternate routes in advance. The switching node responds to a call-connection request to try to connect the call to the first route, and when having failed in the call-connection, the switching node retries the call-connection through one of the assigned routes.
Inventors
- 👤 Hisao Yamamoto
- 👤 Kenichi Mase
- 👤 Akiya Inoue
- 👤 Hiroo Itou
- 👤 Masato Suyama
- 👤 Yoshitaka Hoshi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 06:29
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/64; H04Q3/66
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
193 words
An adaptive routing control method for a telecommunications network in which a plurality of switching nodes are interconnected via links each composed of a plurality of trunks, one or more routes formed by one or more of said links are provided between each node pair made up of two arbitrary ones of said switching nodes, and at least one network control center is connected via a control signal link to each of said switching nodes, said method comprising: a step wherein said network control center adaptively determines, for each said node pair, a set of available routes, composed of routes which are set available based on the traffic volume in said telecommunications network and the trunk status of said links; a step wherein said network control center sends said set of available routes to each switching node of each said node pair; a step wherein each said switching node receives and stores said set of available routes sent from said network control center; and a step wherein each said switching node responds to each call-connection request to select one of said routes from said set of available routes and perform a call-connection procedure.
Claim 2
Dependent Claim
193 words
An adaptive routing control method for a telecommunications network in which a plurality of switching nodes are interconnected via links each composed of a plurality of trunks, one or more routes formed by one or more of said links are provided between each node pair made up of two arbitrary ones of said switching nodes, and at least one network control center is connected via a control signal link to each of said switching nodes, said method comprising: a step wherein said network control center adaptively determines, for each said node pair, a set of available routes, composed of routes which are set available based on the traffic volume in said telecommunications network and the trunk status of said links; a step wherein said network control center sends said set of available routes to each switching node of each said node pair; a step wherein each said switching node receives and stores said set of available routes sent from said network control center; and a step wherein each said switching node responds to each call-connection request to select one of said routes from said set of available routes and perform a call-connection procedure.
Claim 3
Dependent Claim
37 words
The method of claim 1 further comprising a step wherein said network control center updates said sets of available routes at a predetermined time and sends said updated sets of available routes to each said switching node.
Claim 4
Dependent Claim
110 words
The method of claim 1 wherein each said set of available routes is a set of available alternate routes, composed of one or more alternate routes for a first route which is a predefined one of said routes between each said node pair, and further comprising a step wherein each said switching node responds to each said call-connection request to try to find an idle trunk in said first route preferentially, and a step wherein when having failed in finding an idle trunk in said first route, each said switching node tries to find an idle trunk in one of said alternate routes in said set of available alternate routes.
Claim 5
Dependent Claim
113 words
The method of claim 1, 2, or 3 wherein said set of available routes is determined in a manner to satisfy at least one of the following three conditions: (a) letting a traffic volume overflowing from each said set of available routes be identified as a blocked traffic load, said blocked traffic load between one of said switching node pairs which is larger than said blocked traffic load between any other switching node pairs is minimized approximately; (b) the throughput throughout said telecommunications network is maximized approximately; and (c) a call-completion probability between one of said switch-node pairs which is lower than a call-completion probability between any other node pairs is maximized approximately.
Claim 6
Dependent Claim
44 words
The method of claim 3 wherein said network control center includes in said set of available alternate routes for each said first route at least one of alternate routes accommodated in a transmission system different from that in which said first route is accommodated.
Claim 7
Independent Claim
39 words
The method of calim 3 wherein each said switching node adds to said set of available alternate routes at least one of alternate routes accommodated in a transmission system different from that in which said first route is accommodated.
Claim 8
Independent Claim
39 words
The method of calim 3 wherein each said switching node adds to said set of available alternate routes at least one of alternate routes accommodated in a transmission system different from that in which said first route is accommodated.
Claim 9
Dependent Claim
54 words
The method of claim 1, 2, or 3 wherein said step of selecting one of said routes and performing a call-connection procedure by each said switching node includes a step of adaptively selecting one of said routes from said set of available routes in accordance with the distribution of traffic in said telecommunications network.
Claim 10
Dependent Claim
81 words
The method of claim 7 wherein said step of selecting one of said routes from said set of available routes and performing a call-connection by each said switching node includes a step of preselecting one or more available routes from each said set of available routes and assigning said preselected available routes and a step of responding to a request for the connection of a call to select said one route from said assigned available routes and perform said call-connection procedure.
Claim 11
Independent Claim
101 words
The method of calim 8 further including a step wherein as a result of said call-connection procedure using said selected one of said assigned available routes, at least one more available route is selected from said set of available routes and assigned if one of the following three conditions is satisfied: (a) said call could not be connected, (b) said call could be connected but all trunks in said selected one route have become busy, and (c) said call could be connected but the number of idle trunks remaining in said selected one route has become smaller than a predetermined value.
Claim 12
Independent Claim
101 words
The method of calim 8 further including a step wherein as a result of said call-connection procedure using said selected one of said assigned available routes, at least one more available route is selected from said set of available routes and assigned if one of the following three conditions is satisfied: (a) said call could not be connected, (b) said call could be connected but all trunks in said selected one route have become busy, and (c) said call could be connected but the number of idle trunks remaining in said selected one route has become smaller than a predetermined value.
Claim 13
Independent Claim
77 words
The method of calim 1 wherein said step of selecting one of said routes from said set of available routes and performing a call-connection procedure by each said switching node includes a step of preselecting one or more available routes from said set of available routes and assigning said preselected available routes and a step of responding to said request for the connection of a call to select a currently available one of said assigned available routes.
Claim 14
Independent Claim
77 words
The method of calim 1 wherein said step of selecting one of said routes from said set of available routes and performing a call-connection procedure by each said switching node includes a step of preselecting one or more available routes from said set of available routes and assigning said preselected available routes and a step of responding to said request for the connection of a call to select a currently available one of said assigned available routes.
Claim 15
Dependent Claim
79 words
The method of claim 10 further comprising a step wherein when said call requesting each said switching node for connection is a call to be relayed from one of the other switching nodes which is the originating node of said call to another one of them which is the terminating node of said call, said switching node transfers to said originating node trunk-status information of said link constituting said selected assigned available route and connected to said terminating node.
Claim 16
Dependent Claim
54 words
The method of claim 11 further comprising a step wherein when said trunk-status information received by said originating node indicates a high possibility of a call being blocked in said link connected to said terminating node, said originating node sets said assigned available routes including said link unavailable for a predetermined period of time.
Claim 17
Dependent Claim
58 words
The method of claim 12 further comprising a step wherein when the number of those of said assigned available routes which are not unavailable becomes smaller than a predetermined value, said switching node cancels the assignment of at least said assigned available routes having been set unavailable and newly assigns those of said available routes which are assignable.
Claim 18
Dependent Claim
24 words
The method of claim 13 further comprising a step of inhibiting the assignment of said assignment-canceled available routes for a predetermined period of time.
Claim 19
Dependent Claim
83 words
The method of claim 11 further comprising a step wherein when said trunk-status information received by said originating node indicates a high possibility of a call being blocked in said link connected to said terminating node, said originating node cancels the assignment of said assigned available routes including said link and inhibits their reassignment for a predetermined period of time, and a step wherein said originating node assigns one of said available routes which are assignable, in place of said assignment-canceled available routes.
Claim 20
Dependent Claim
30 words
The method of claim 14 or 15 wherein said predetermined period of time for which the assignment of said assignment-canceled available routes is inhibited is a fixed period of time.
Claim 21
Dependent Claim
33 words
The method of claim 14 or 15 wherein said predetermined period of time for which the assignment of said assignment-canceled available routes is inhibited is determined on the basis of said trunk-status information.
Claim 22
Dependent Claim
51 words
The method of claim 10 further comprising a step wherein when no idle trunk is found in an outgoing link constituting said assigned available route selected by each said switching node in response to said call-connection request, said selected assigned available route is set unavailable for a predetermined period of time.
Claim 23
Dependent Claim
49 words
The method of claim 18 further comprising a step wherein when no idle trunk is found in said outgoing link constituting said selected assigned available route, each said switching node repeats said call-connection procedure, using one of the other assigned available routes which are not in an unavailable status.
Claim 24
Dependent Claim
38 words
The method of claim 18 or 19 further comprising a step wherein when all of said assigned available routes are unavailable, said switching node cancels their assignments and newly assigns those of said available routes which are assignable.
Claim 25
Independent Claim
23 words
The method of calim 19 further including a step of inhibiting assignment of said assignment-canceled available routes for a predetermined period of time.
Claim 26
Independent Claim
23 words
The method of calim 19 further including a step of inhibiting assignment of said assignment-canceled available routes for a predetermined period of time.
Claim 27
Dependent Claim
34 words
The method of claim 12 wherein said predetermined period of time for which said assigned available routes are set unavailable is based on the time at which said originating node receives said trunk-status information.
Claim 28
Dependent Claim
56 words
The method of claim 12 wherein said switching node for transiting said call transfers the time of observation of the trunk status of said link to said originating node together with said trunk-status information, and based on said received observation time, said originating node sets said assigned available routes unavailable for said predetermined period of time.
Claim 29
Dependent Claim
30 words
The method of claim 22 or 23 wherein said predetermined period of time for which said assigned available routes are set unavailable is determined in accordance with said trunk-status information.
Claim 30
Dependent Claim
26 words
The method of claim 22 or 23 wherein said predetermined period of time for which said assigned available routes are set unavailable is a fixed period.
Claim 31
Dependent Claim
69 words
The method of claim 11 further comprising a step wherein said switching node for transiting said call performs a procedure for connecting said call to said trunk of said link which constitutes said selected assigned available route and is connected to said terminating node, receives from said terminating node a response singal indicating the completion or blocking of said call and sends said response signal to said originating node.
Claim 32
Dependent Claim
28 words
The method of claim 26 wherein said switching node for transiting said call appends said trunk-status information to said response signal and sends them to said originating node.
Claim 33
Dependent Claim
26 words
The method of claim 26 wherein said switching node for transiting said call sends said trunk-status information to said originating node separately of said response signal.
Claim 34
Dependent Claim
132 words
The method of claim 1 further comprising a step wherein when said call requesting said switching node for connection is a call to be transited from one of the other switching nodes which is the originating node of the call to another one of them which is the terminating node of said call, said switching node transfers to said originating node trunk-status information of said link which constitutes said selected available route and is connected to said terminating node, a step wherein upon each reception of said trunk-status information corresponding to said selected available route, said originating node stores and updates said trunk-status information, and a step wherein said originating node responds to said call-connection request to select one of said available routes based on said trunk-status information of each of them.
Claim 35
Dependent Claim
50 words
The method of claim 29 wherein said step of selecting one of said available routes includes a step of determining the choice probability of each of said available routes based on the trunk-status information thereof, and a step of selecting one of said available routes based on said choice probability.
Claim 36
Dependent Claim
37 words
The method of claim 29 wherein said trunk-status information is the number of idle trunks of each of said links and that one of said available routes which is selected has the largest number of idle trunks.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.