Packet switch network for communication using packet having virtual connection identifier VCI

Claim 2

A packet network comprising a plurality of packet switching stations (52, 54, 56, 58), in which a packet including in its header portion a virtual connection identifier for identifying a logical connec­tion which determines a transmission route of the packet is communicated between the packet switching stations, any given one of said packet switching stations comprising: means (1, 2, 3, 4) for determining, when a logical connection is set up between said given packet switching station and any one of the other packet switching stations, a first virtual connection identifier to be given to each information packet subsequently transmitted from said other packet switching station by use of the logical connection and informing said other packet switching station of said first virtual connection identifier by a control packet; and means (1, 2, 3, 4) for giving, when said given packet switching station transmits an information packet to said other packet switching station, a second virtual connection identifier preliminarily designated from said other packet switching station to said each information packet and delivering the resultant infor­mation packet onto an outgoing line to which said other packet switching station is connected.

Claim 3

A packet network according to Claim 1, wherein said each packet includes in its header portion a virtual logical path identifier for identifying a logical path including a plurality of multiplexed logical connections having the same packet transmission direction, and wherein said given packet switching station includes: a plurality of incoming lines (5) and a plurality of outgoing lines (8) respectively connected to the other packet switching stations; switch means (1) connected between said incoming lines and said outgoing lines, said switch means operating to output an input packet to either one of said outgoing lines in accordance with routing information given to the input packet; and label conversion means (2, 3) for giving routing information to a received packet inputted to each of said incoming lines to said switch means to input the resultant packet to said switch means and re­moving said routing information from a packet outputted from said switch emans, said routing information being determined in accordance with the first virtual con­nection identifier included in the received packet.

Claim 4

A packet network according to Claim 2, wherein said label conversion means (2, 3) includes a plurality of first label conversion means (11, 12, 13, 14) respectively provided for said incoming lines and a plurality of second label conversion means (22, 23, 24, 25, 26) respectively provided for said outgoing lines (8), each of said plurality of first label conversion means including first table means (14) for storing routing information in correspondence to a first virtual connection identifier to be included in each packet received from the incoming line connected to the first label conversion means and first control means (13) for rewriting the virtual logical path identifier field included in each received packet to be set with the routing information read from said first table means and inputting the resultant packet to said switch means, and each of said second label conversion means including second table means (24) for storing, a virtual logical path identifier which is to be removed from each received packet prior to the inputting of the packet to said switch means and a second virtual connection identifier which is to be given to an output packet and is pre­liminarily designated from the other packet switching station, in correspondence to a first virtual connection identifier to be included in each received packet and second control means (23) for rewriting a virtual connection identifier field and a routing information field included in the packet outputted from said switch means to be respectively set with the second virtual connection identifier and the virtual logical path identifier read from said second table means.

Claim 5

A packet network according to Claim 3, wherein an internal virtual connection identifier is stored together with said routing information in each of said first table means (14) in correspondence to each first vurtual connection identifier, said first control means (13) rewrites the virtual connection identifier field and a virtual logical path identifier field included in said received packet to be respec­tively set with the internal virtual connection identifier and the routing information read from the first table means, said virtual logical path identifier and said second virtual connection identifier are stored in each of said second table means (24) in correspondence to said internal virtual connection identifier, and said second control means (23) reads one pair of the virtual logical path identifier and the second virtual connection identifier from said second table means in accordance with the internal virtual connection identifier included in the packet outputted from said switch means (1).

Claim 8

A method according to Claim 5, wherein each of said plurality of switching stations includes a plurality of incoming lines (5) respectively connected to the other switching stations, input side interfaces (2) respectively provided for said incoming lines, a plurality of outgoing lines (7) respectively connected to the other switching stations, output side interfaces (3) respectively provided for said outgoing lines, and a switch (1) provided between said input side interfaces and said output side interfaces, wherein said first step includes a step of storing, routing information for specifying one of the outgoing lines onto which a control packet delivered from any one of the other switching stations is to be delivered, into a memory (14) of one of the input side interfaces which receives a control packet delivered from said either one of the other switching stations, in correspondence to a first virtual connection identifier field of said control packet and a step of storing, a virtual path identifier set in a virtual path identifier field of said received control packet and a second virtual connection identifier set in a data field of said received control packet, into a memory (24) of one of the output side interfaces which is connected to the one outgoing line specified by said routing information, in correspondence to said first virtual connection identifier, and wherein said second step includes a step of reading, in the input side interface which receives an information pakcet delivered from either one of the other switching stations, routing information corresponding to a first virtual connection identifier included in a virtual connection identifier field of said information packet from the memory of the input side interface and giving the read routing information to a virtual path identifier field of said information packet, a step of switching an information packet outputted from said input side interface to one of the output side interfaces in accordance with said routing information, and a step of reading, in said one output side interface which receives said information packet, a virtual path identifier and a second virtual connection identifier corresponding to the first virtual connection identifier included in the virtual connection identifier field of said information packet from the memory of said one output side interface and giving the read virtual path identifier and second virtual connection identifier to the virtual path identifier field and the virtual connection identifier field of said information packet, respectively.

Claim 9

A method according to Claim 6, wherein in said storing step performed in said input side interface (2) an internal virtual connection identifier is stored together with said routing information into the memory (14) of said output side interface in said storing step performed in said output sdie interface (3) said virtual path identifier and said second virtual connection identifier are stored into the memory (24) of said output side interface, in correspondence to said internal virtual connection identifier substituted for said first virtual connection identifier, in said giving step performed in said input side interface the routing infor­mation and the internal connection identifier are read from the memory of said input side interface and said internal virtual connection identifier is given to the virtual connection field of the information packet, and in said giving step performed in said output side inter­face the virtual path identifier and the second virtual connection identifier corresponding to the internal virtual connection identifier included in the vritual connection identifier field of the information packet are read.