Circulating switch

1. A switch for switching data stream segments between network links comprising:

a rotator; and

a plurality of switch modules, each switch module having a memory and being for:

receiving new data stream segments from at least one external data source through an ingress network link;

storing said new data stream segments in said memory;

transmitting said new data stream segments to other switch modules from among said plurality of switch modules through said rotator;

receiving other data stream segments from said other switch modules through said rotator;

storing said other data stream segments in said memory;

and

transmitting at least a portion of said other data stream segments out on an egress network link;

said rotator for cyclically directly connecting said each switch module to each other switch module of said other switch modules during a rotation cycle comprising a number of phases, where, during each phase, said rotator directly connects said each switch module to one of said other switch modules.

2. The switch of claim 1 wherein said new data-stream segments are transferred along at least one indirect connection from said each switch module to a destination switch module from among said plurality of switch modules, where an indirect connection traverses a transit switch module, where said transit switch module is selected from among said plurality of switch modules excluding said each switch module and said destination switch module.

3. The switch of claim 2 further comprising a plurality of rotators, each rotator of said plurality of rotators for temporarily providing a direct connection between said each switch module and said each other switch module to allow for data stream segments to be directly transferred from said each switch module to said each other switch module.

4. The switch of claim 3 wherein at least two rotators of said plurality of rotators rotate in opposite directions.

5. The switch of claim 4 wherein said indirect connection traverses two rotators rotating in opposite directions.

6. A circulating switch comprising a plurality of switch modules containing N switch modules, N>2, wherein:

each switch module of said plurality of switch modules is configured to cyclically connect to each other switch module of said plurality of switch modules through m parallel rotators arranged into a first group of m 1 clockwise rotators and a second group of m 2 counterclockwise rotators, m>1, m 1 ≧1, m 2 ≧1; and

said each switch module is configured to transfer data to said each other switch module of said plurality of switch modules through:

m direct paths, each said direct path traversing only one of said m parallel rotators; and

a plurality of sets of indirect paths comprising 2×m 1 ×m 2 sets of indirect paths, each set of indirect paths of said plurality of sets of indirect paths including N−2 indirect paths traversing a respective sub-set of said rotators such that said N−2 indirect paths are associated with an alike transfer delay, said alike transfer delay being specific to said each set of indirect paths.

7. The circulating switch of claim 6 wherein at least one of said switch modules is configured to receive data from external sources through at least one input channel and at least one of said switch modules is configured to transmit data on at least one output channel to external sinks.

8. The circulating switch of claim 6 wherein each indirect path in said each set of indirect paths traverses one of said m 1 clockwise rotators, one transit switch module from among said plurality of switch modules, and one of said m 2 counterclockwise rotators.

9. The circulating switch of claim 6 wherein said alike transfer delay is specific to a pairing of said each switch module with said each other switch module and said respective sub-set of said rotators.

10. The circulating switch of claim 6 further including a plurality of module controllers, each module controller of said plurality of module controllers associated with one of said switch modules, said each module controller for selecting a direct path from among said m direct paths.

11. The circulating switch of claim 10 wherein said each module controller selects a set of indirect paths from among said sets of indirect paths.

12. The circulating switch of claim 10 further including a master controller for receiving connection requests from said module controllers.

13. The circulating switch of claim 12 wherein said master controller is directly connected to each of said module controllers.

14. The circulating switch of claim 12 wherein said master controller connects to one of said switch modules and communicates with said switch modules through said one of said switch modules.

15. The circulating switch of claim 11 wherein said each module controller associates an ordered pair of said switch modules selected from among said plurality of switch modules with a preferred set of indirect paths selected from said plurality of sets of indirect paths.

16. The circulating switch of claim 6 wherein each direct path of said m direct paths is established during a time slot of a predetermined duration.

17. A circulating switch comprising:

a set of m switch modules, m>2, said m switch modules interconnected in a temporal mesh wherein each switch module of said set of switch modules directly connects to each other switch module of said set of switch modules during a corresponding set of n time slots, n≧1,in a predefined time frame, said predefined time frame having a number of time slots at least equal to m; and

said temporal mesh defining, in conjunction with said predefined time frame, a set of indirect temporal paths from said each switch module to said each other switch module, each indirect temporal path from an origin switch module to a destination switch module directly connecting said origin switch module to an intermediate switch module during a first selected time slot among a first corresponding set of n time slots and directly connecting said intermediate switch module to said destination switch module during a second selected time slot among a second corresponding set of n time slots, said first switch module, second switch module, and intermediate switch module belonging to said set of m switch modules.

18. The circulating switch of claim 17 wherein said first selected time slot and second selected time slot are determined so that said each indirect temporal path guarantees temporal order of data segments transmitted from said origin switch module to said destination switch module.

19. The circulating switch of claim 17 wherein said each switch module is for receiving and sending data segments, each data segment having a same predefined size, and said each switch module has a memory device logically partitioned into:

a shipping section for storing new data segments received from data sources;

a transit section for storing transit data segments received from a first switch module among said plurality of switch modules and directed to a second switch module among said m switch modules, where said second switch module is other than said each switch module; and

a receiving section for storing received data segments for delivery to data sinks associated with said each switch module.

20. The circulating switch of claim 19 wherein a storage capacity of said transit section is limited to:

m times a predefined number of transit data segments per switch module times said predefined size.