Communication network design method and communication equipment

Claim 2

Communication network design method as set forth in Claim 1, wherein it is ensured that, for the aforementioned plurality of VCHs, a VP which does not pass through any other VCH can be established between any two given VCHs.

Claim 3

Communication network design method as set forth in Claims 1 or 2, wherein a VCH interconnection network is established by assigning different VPs to each media or service consisting of information to be transferred.

Claim 4

Communication network design method as set forth in Claims 1 or 2, wherein a VCH interconnection network is established by allowing a plurality of media or services with the same destination VCH to be assigned a single VP.

Claim 5

Communication network design method as set forth in Claim 4, wherein priority control is performed between VCs with the same destination in accordance with a priority ranking of the media or service consisting of information to be transferred.

Claim 6

Communication network design method as set forth in any of Claims 1 to 5, wherein the network topologies of a plurality of VCH interconnection networks for different kinds of media or service are designed simultaneously after taking their overall optimization into consideration.

Claim 7

Communication network design method as set forth in Claim 6, wherein an optimized network topology is obtained by calculating the network resource efficiency from the working VP ratio, which is defined as the ratio of working VP capacity to total capacity of working and back-up VPs, and from the VP use efficiency, which has been calculated from the traffic type, traffic demand and required cell loss probability of VCs.

Claim 8

Communication network design method as set forth in Claim 7, wherein the number of disjoint routes D (i.e., the number of paths between origin and destination VCHs which do not pass through the same VCHs or VP links) is set as a parameter of trial network topology; and satisfying the given number of disjoint routes D is set as a constraint; and a trial network topology such that the total length of all the VP links is minimized is formed; and the aforementioned number of disjoint routes D is changed when the trial network topology is changed; and network resource efficiency is calculated for the trial network topology obtained.

Claim 9

Communication network design method as set forth in Claim 7, wherein network topology is designed so that the overall communication network cost is minimized.

Claim 10

Communication network design method as set forth in Claim 9, wherein connection or disconnection of VP connections between VCHs for establishing VCH interconnection network is performed in parallel with establishing VCH interconnection networks for other media or services.

Claim 11

Communication network design method as set forth in any of Claims 1 to 5, wherein the network topologies of a plurality of VCH interconnection networks for different kinds of media or service are designed in a particular order.

Claim 12

Communication network design method as set forth in Claim 11, wherein the design priority order of the topologies of a network is set in the order of decreasing network cost of the media or services supported by its VCH interconnection networks.

Claim 13

Communication network design method characterised in that: network topologies are designed in accordance with the communication network design method set forth in Claims 11 or 12; the proportion of overall network cost accounted for by the network cost of the VCH interconnection network for each media or service is calculated; the design priority order is set again in accordance with the results of this calculation; and if this design priority order is different from the previous time, the design of network topologies is repeated in accordance with the new design priority order.

Claim 14

Communication network design method as set forth in Claim 13, wherein a limit is set for the number of repetitions.

Claim 15

Communication network design method as set forth in any of Claims 9 to 14, wherein network topologies are designed after setting an upper limit for the number of VPs passed through from an origin VCH to a destination VCH.

Claim 16

Communication network design method as set forth in any of Claims 1 to 5, wherein: media or services are classified into a priority group and a non-priority group according to their network cost; the design of VCH interconnection network topologies for the priority group is performed in the order of decreasing network cost; the design of VCH interconnection network topologies for the non-priority group is performed simultaneously in such manner that overall network cost is minimized.

Claim 17

Communication equipment which has: a plurality of virtual channel handlers (VCHs) which perform switching in units of virtual channels (VCs); a virtual path handler (VPH) which changes over routes in units of virtual paths (VPs) which accommodate a plurality of VCs; a transmission link network which physically connects the aforementioned plurality of VCHs and the VPH; and a higher order means which establishes a VP network on this transmission link network, said VP network being formed from VPs which logically connect the aforementioned plurality of VCHs; and which also establishes a VC network on this VP network, said VC network being formed from VCs which logically connect subscribers; said communication equipment being characterised in that the aforementioned higher order means includes: a VCH interconnection network establishing means which establishes, on the VP network, a different VCH interconnection network for each media or service consisting of information to be transferred; and a means which forms VC networks corresponding to these media or services by means of these respective VCH interconnection networks, whereby a plurality of VC networks for different media or services are established simultaneously on a single physical network.