Free space optical, growable packet switching arrangement

Claim 2

A packet switching arrangement having L input ports, M intermediate ports and N output ports, where L, M and N are positive integers greater than two, said arrangement comprising a distribution network for switching packets from said L input ports to said M intermediate ports without storing full received packets, and N/n output packet switching modules, where n and N/n are positive integers with N>n>1, each of said modules comprising means for switching packets from a distinct group of m of said intermediate ports to a distinct group of n of said output ports, where m is a positive integer with m>n, and means for storing full received packets, said distribution network comprising S stages of opto-electronic nodes, with each node of at least the first (S-1) of said node stages comprising an X×Y switching means, where S, X and Y are positive integers with S>3, X>1, and Y>1, and where log 2 (max (L,N))<S+1<[log 2 (max (L,N))] 2 /2, and (S-1) free-space optical link stages interconnecting successive ones of said S node stages.

Claim 3

An arrangement in accordance with claim 1 wherein said distribution network has a probability of blocking less than the square root of ##EQU54## where ρ L is the network loading.

Claim 4

An arrangement in accordance with claim 1 wherein each node of at least the interior (S-2) of said S node stages has at least three optical inlets and at least three optical outlets.

Claim 5

An arrangement in accordance with claim 3 where X=2, Y=2 and the X×Y switching means of said each node of said at least the first (S-1) of said node stages and certain links of at least the first (S-2) of said link stages collectively comprise a Banyan network, a Banyan network with omitted link stages, or a topological equivalent to either.

Claim 6

An arrangement in accordance with claim 1 wherein said each node of said at least the first (S-1) of said node stages has only two optical inlets and only two optical outlets.

Claim 7

An arrangement in accordance with claim 4 where X=2, Y=2 and said S node stages and said (S-1) link stages collectively comprise an extended generalized shuffle network or a topological equivalent.

Claim 8

An arrangement in accordance with claim 1 wherein at least one of said (S-1) link stages comprises binary phase grating means optically interposed between a first one and a second one of two successive ones of said S node stages.

Claim 9

An arrangement in accordance with claim 7, said grating means being responsive to each optical beam transmitted from said first node stage for transmitting a plurality of optical beams to said second node stage and wherein said second node stage is responsive to less than all of said plurality of beams.

Claim 10

An arrangement in accordance with claim 8 wherein said at least one link stage further comprises a first lens optically interposed between said first node stage and said grating means, and a second lens optically interposed between said grating means and said second node stage.

Claim 11

An arrangement in accordance with claim 1 with X=2 and Y=2 and where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises first means for transmitting a packet, being received on a first one of said input beams, on a selected one of said output beams, and second means for transmitting a packet, being received on a second one of said input beams, on the one of said output beams other than said selected output beam.

Claim 12

An arrangement in accordance with claim 1 with X=2 and Y=2 and where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises means, responsive to the absence of a packet on a first one of said input beams, for transmitting a packet, being received on a second one of said input beams, on a selected one of said two output beams.

Claim 13

An arrangement in accordance with claim 1 with X=2 and Y=2 and where said X×Y switching means transmits two optical output beams and said X×Y switching means comprises means responsive to a packet being received including destination information, for selecting one of said two output beams, based on said destination information, for transmission of said packet being received.

Claim 14

An arrangement in accordance with claim 12 wherein said destination information defines one of said output ports but any one of a plurality of paths through said distribution network may be used to transmit said packet being received, to said defined port.

Claim 15

An arrangement in accordance with claim 1 wherein said X×Y switching means comprises a FET-SEED circuit.

Claim 16

An arrangement in accordance with claim 1 wherein said X×Y switching means comprises two S-SEED detectors, two S-SEED modulators, and an electronic logic circuit interposed between said two detectors and said two modulators.

Claim 17

An arrangement in accordance with claim 1 wherein said X×Y switching means comprises two means for receiving optical beams, two means for transmitting optical beams, and an electronic logic circuit interposed between said two receiving means and said two transmitting means.

Claim 18

An arrangement in accordance with claim 1 wherein said intermediate ports are connected to said output packet switching modules via optical fibers.

Claim 19

A packet switching arrangement having L input ports, M intermediate ports and N output ports, where L, M and N are positive integers greater than two, said arrangement comprising a distribution network for switching packets from said L input ports to said M intermediate ports without storing full received packets, and N/n output packet switching modules, where n and N/n are positive integers with N>n>1, each of said modules comprising means for switching packets from a distinct group of m of said intermediate ports to a distinct group of n of said output ports, where m is a positive integer with m>n, and means for storing full received packets, said distribution network comprising S stages of opto-electronic nodes, with each node of at least the first (S-1) of said node stages comprising an X×Y switching means, where S, X and Y are positive integers with S>3, X>1, and Y>1, and (S-1) free-space optical link stages interconnecting successive ones of said S node stages, where X=2, Y=2 and the X×Y switching means of said each node of said at least the first (S-1) of said node stages and certain links of at least the first (S-2) of said link stages collectively comprise a Banyan network, a Banyan network with omitted link stages, or a topological equivalent to either.

Claim 20

A packet switching arrangement having L input ports, M intermediate ports and N output ports, where L, M and N are positive integers greater than two, said arrangement comprising a distribution network for switching packets from said L input ports to said M intermediate ports without storing full received packets, and N/n output packet switching modules, where n and N/n are positive integers with N>n>1, each of said modules comprising means for switching packets from a distinct group of m of said intermediate ports to a distinct group of n of said output ports, where m is a positive integer with m>n, and means for storing full received packets, said distribution network comprising S stages of opto-electronic nodes, with each node of at least the first (S-1) of said node stages comprising an X×Y switching means, where S, X and Y are positive integers with S>3, X>1, and Y>1, and (S-1) free-space optical link stages interconnecting successive ones of said S node stages, where X=2, Y=2 and the X×Y switching means of said each node of said at least the first (S-1) of said node stages and certain links of at least the first (S-2) of said link stages collectively comprise a Banyan network, a Banyan network with omitted link stages, or a topological equivalent to either.

Claim 21

An arrangement in accordance with claim 18 where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises first means for transmitting a packet, being received on a first one of said input beams, on a selected one of said output beams, and second means for transmitting a packet, being received on a second one of said input beams, on the one of said output beams other than said selected output beam.

Claim 22

An arrangement in accordance with claim 18 where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises means, responsive to the absence of a packet on a first one of said input beams, for transmitting a packet, being received on a second one of said input beams, on a selected one of said two output beams.

Claim 23

An arrangement in accordance with claim 18 where said X×Y switching means transmits two optical output beams and said X×Y switching means comprises means responsive to a packet being received including destination information, for selecting one of said two output beams, based on said destination information, for transmission of said packet being received.

Claim 24

An arrangement in accordance with claim 21 wherein said destination information defines one of said output ports but any one of a plurality of paths through said distribution network may be used to transmit said packet being received, to said defined port.

Claim 25

An arrangement in accordance with claim 18 wherein said X×Y switching means comprises a FAT-SEED circuit.

Claim 26

A packet switching arrangement having L input ports, M intermediate ports and N output ports, where L, M and N are positive integers greater than two, said arrangement comprising a distribution network for switching packets from said L input ports to said M intermediate ports without storing full received packets, and N/n output packet switching modules, where n and N/n are positive integers with N>n>1, each of said modules comprising means for switching packets from a distinct group of m of said intermediate ports to a distinct group of n of said output ports, where m is a positive integer with m>n, and means for storing full received packets, said distribution network comprising S stages of opto-electronic nodes, with each node of at least the first (S-1) of said node stages comprising an X×Y switching means, where S, X and Y are positive integers with S>3, X>1, and Y>1, and (S-1) free-space optical link stages interconnecting successive ones of said S node stages, wherein at least one of said (S-1) link stages comprises binary phase grating means optically interposed between a first one and a second one of two successive ones of said S node stages, said grating means being responsive to each optical beam transmitted from said first node stage for transmitting a plurality of optical beams to said second node stage and wherein said second node stage is responsive to less than all of said plurality of beams.

Claim 27

A packet switching arrangement having L input ports, M intermediate ports and N output ports, where L, M and N are positive integers greater than two, said arrangement comprising a distribution network for switching packets from said L input ports to said M intermediate ports without storing full received packets, and N/n output packet switching modules, where n and N/n are positive integers with N>n>1, each of said modules comprising means for switching packets from a distinct group of m of said intermediate ports to a distinct group of n of said output ports, where m is a positive integer with m>n, and means for storing full received packets, said distribution network comprising S stages of opto-electronic nodes, with each node of at least the first (S-1) of said node stages comprising an X×Y switching means, where S, X and Y are positive integers with S>3, X>1, and Y>1, and (S-1) free-space optical link stages interconnecting successive ones of said S node stages, wherein at least one of said (S-1) link stages comprises binary phase grating means optically interposed between a first one and a second one of two successive ones of said S node stages, said grating means being responsive to each optical beam transmitted from said first node stage for transmitting a plurality of optical beams to said second node stage and wherein said second node stage is responsive to less than all of said plurality of beams.

Claim 28

An arrangement in accordance with claim 24 with X=2 and Y=2 and where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises first means for transmitting a packet, being received on a first one of said input beams, on a selected one of said output beams, and second means for transmitting a packet, being received on a second one of said input beams, on the one of said output beams other than said selected output beam.

Claim 29

An arrangement in accordance with claim 24 with X=2 and Y=2 and where said X×Y switching means is responsive to two optical input beams and transmits two optical output beams and said X×Y switching means comprises means, responsive to the absence of a packet on a first one of said input beams, for transmitting a packet, being received on a second one of said input beams, on a selected one of said two output beams.

Claim 30

An arrangement in accordance with claim 24 with X=2 and Y=2 and where said X×Y switching means transmits two optical output beams and said X×Y switching means comprises means responsive to a packet being received including destination information, for selecting one of said two output beams, based on said destination information, for transmission of said packet being received.

Claim 31

An arrangement in accordance with claim 24 wherein said destination information defines one of said output ports but any one of a plurality of paths through said distribution network may be used to transmit said packet being received, to said defined port.

Claim 32

An arrangement in accordance with claim 24 wherein said X×Y switching means comprises a FAT-SEED circuit.