Optical Flow Switching

Chan, Weichenberg, and Medard Optical Flow Switching. A proposed communications protocol, but one which has some insights for transportation (if not immediate applicability)

Motivated by the minimization of network management and switch complexity in the network core, flows are serviced as indivisible entities. That is, data cells comprising a flow traverse the network contiguously in time, along the same wavelength channel, and along the same spatial network path. This is in contrast to packet switched networks, where transactions are broken up into constituent cells, and these cells are switched and routed through the network independently. Note that in OFS networks, unlike packet switched networks, all queuing of data occurs at the end users, thereby obviating the need for buffering in the network core. Core nodes are thus equipped with bufferless optical cross-connects (OXCs). OFS is a centralized transport architecture in that coordination is required for logical topology reconfiguration. However, OFS traffic in the core will likely be efficiently aggregated and sufficiently intense to warrant a quasi-static logical topology that changes on coarse time scales. Hence, the centralized management and control required for OFS is not expected to be onerous. The network management and control carried out on finer time-scales will be distributed in nature in that only the relevant ingress and egress access networks will need to communicate.
(emphasis added)

So instead of storing and buffering (on-road queueing), they allocate the whole path between origin and destination to the flow (a trip).

Of course, since this is communications, there are some things they can do that transportation cannot:

If any errors are detected, a request for retransmission of the whole file is done via feedback to the transmitter.

(Sorry, your trip didn't work out, please have your clone repeat the trip).

David Levinson

Network Reliability in Practice

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This page contains a single entry by David Levinson published on June 29, 2010 10:14 AM.

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