Abstract: A packet is routed by “dead reckoning” on a network having a generally regular topology. The packet is received at a node where a local routing decision is made. The packet is output in a direction selected according to the routing decision. The packet carries in addition to a destination address a directional flag indicating explicitly the preferred direction of onward travel and the routing decision is made using this flag. Several flags may be used, corresponding to different dimensions of the network.

Abstract: A packet carried on an optical network is routed by carrying out a logic operation on an address word carried in a packet header and a predetermined discriminator word. A routing decision is made in accordance with the result of the logic operation. The logic operation may be a bit-wise Boolean AND operation. An additional logic operation may be carried out with an additional discriminator word to determine whether the packet is destined for a remote region of the network. In this case, the packet may be steered directly to the remote region.

Abstract: An optical AND gate includes at least one semiconductor laser amplifier (SLA) and inputs for first and second optical signals. The gate produces an output corresponding to the AND product of A and B. In one aspect of the invention, the first and second signals are equal in wavelength. The gate may comprise a single SLA which receives the first signal A together with a third signal P, which may be a continuous wave pump. The second signal B is input in an orthogonal polarization state to A and P. Alternatively, the gate may comprise a pair of SLAs. A first SLA receives the first signal A together with the pump P. A sideband is selected from the output of the first SLA and input to the second SLA together with the second signal B. A sideband is selected from the output of the second SLA corresponding to the AND product C of A and P with B.

Abstract: A packet carried on an optical network is routed by carrying out a logic operation on an address word carried in a packet header and a predetermined discriminator word. A routing decision is made in accordance with the result of the logic operation. The logic operation may be a bit-wise Boolean AND operation. An additional logic operation may be carried out with an additional discriminator word to determine whether the packet is destined for a remote region of the network. In this case, the packet may be steered directly to the remote region.