Communication network apparatus and method

• US 20030142634A1
• Filed: 12/23/2002
• Published: 07/31/2003
• Est. Priority Date: 12/21/1998
• Status: Active Grant

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Lu, Xiaolin
• Granted Patent: US 7,298,710 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/62 Wavelength based optical switching H04Q11/0062

Abstract

A communication network apparatus and method for routing communication signals from a source device to a receiving device. The apparatus performs only local processing on communication signals to thereby increase the speed of processing the signals. A plurality of the processing nodes are combined into a plurality of sub-networks that comprise the network apparatus. Each processing node of a sub-network need only process address information pertaining to the node'"'"'s current layer, one layer above it, if any, and one layer below it, if any. Additionally, each processing node has associated communication signal frequencies/wavelengths that identify the processing node as the intended recipient of the communication signal. When a communication signal having a carrier signal with a frequency/wavelength corresponding to the processing node is received, the processing node demodulates the carrier signal and forwards the communication signal data to a processing module used to process address information to determine how to route the communication signal through the network. Communication signals may be assigned “express” frequencies/wavelengths, in which case, all of the processing nodes, except the destination processing node, of the network pass the communication signal without performing processing on the communication signal.

Claims

1. A method for configuring a network, comprising:

grouping processing nodes of the network into a plurality of sub-networks;

organizing the sub-networks into layers where sub-networks within each layer are not directly coupled to each other; and

coupling processing nodes of a layer to at least one processing node of an above sub-network of an upper layer, unless the layer is a top layer, and at least one processing node of a below sub-network of a lower layer, or a child device.

2. The method of claim 1, further comprising coupling each processing node of each sub-network to one or more other processing nodes of the sub-network.

3. The method of claim 1, further comprising:

coupling each processing node of a sub-network to one processing node of an immediately above sub-network; and

coupling each processing node of the sub-network to at least one processing node of a below-sub-network.

4. The method of claim 1, further comprising:

coupling only one processing node of a sub-network to a processing node of an immediately above sub-network; and

coupling at least one processing node of the sub-network to one processing node of a below-sub-network.

5. The method of claim 1, further comprising:

partitioning an address space of the communication network to correspond to the layers of sub-networks; and

identifying a first portion address, a second portion address, and a third portion address of an address of the address space, wherein the first portion address corresponds to processing nodes of above sub-networks, the second portion address corresponds to processing nodes of same sub-networks, and the third portion address corresponds to below sub-networks or child devices.

6. The method of claim 1, wherein coupling the processing nodes of a layer further comprises:

coupling processing nodes of a layer to at least one processing node of a plurality of above sub-networks of an upper layer, unless the layer is a top layer.

7. The method of claim 1, wherein the network is a telecommunications network.

8. A method for routing communication signals in a network organized into layers of sub-networks, comprising:

receiving in a sub-network, a communication signal from another sub-network or a child device;

selecting a carrier signal based on a destination address of the communication signal; and

outputting the carrier signal to one of an above sub-network, a below sub-network, a same sub-network, or a child device.

9. The method of claim 8, wherein each sub-network of each layer in the network is comprised of at least one processing node, and wherein the communication signal is received by one of the at least one processing nodes in the sub-network.

10. The method of claim 9, further comprising:

extracting a first portion address from the destination address;

selecting a carrier signal corresponding to a first processing node of an above sub-network if the first portion address does not include an address of the first processing node of the above sub-network; and

outputting the carrier signal to the first processing node.

11. The method of claim 10, further comprising:

selecting a carrier signal corresponding to a second processing node of a below sub-network if the first portion address does include the address of the first processing node of the above sub-network; and

outputting the carrier signal to the second processing node.

12. The method of claim 8, further comprising:

outputting the carrier signal to a child device if the destination address is directed to a child device.

13. The method of claim 8, wherein carrier signals have a plurality of possible frequencies and each of a plurality of processing nodes of the network is assigned at least one carrier signal frequency that is received and processed by the processing node.

14. The method of claim 8, wherein carrier signals have a plurality of possible wavelengths and each of the at least one processing node of each layer is assigned at least one carrier signal wavelength that is received and processed by the processing node.

15. The method of claim 8, further comprising:

receiving the communication signal in a processing node of a sub-network from a processing node in an above sub-network;

outputting the communication signal to a child device if a destination address of the communication signal is directed to the child device and the child device is reachable without going through another processing node; and

selecting a carrier signal that corresponds to a processing node of a below sub-network if the destination address is not directed to a child device.

16. The method of claim 10, further comprising:

extracting a second portion address from the destination address if the first portion address includes the address of the first processing node;

selecting a carrier signal having a frequency that corresponds to a third processing node of a same sub-network if the second portion address does not correspond to an address of a current processing node;

modulating the carrier signal with the communication signal; and

outputting the modulated carrier signal to the third processing node.

17. The method of claim 16, wherein if the second portion address does correspond to an address of a current processing node, the method further comprises:

extracting a third portion address from the destination address;

selecting a carrier signal having a frequency that corresponds to a fourth processing node if the third portion address does not correspond to the child device;

modulating the carrier signal with the communication signal; and

outputting the modulated carrier signal to the fourth processing node.

18. The method of claim 8, wherein if the destination address does not include an address for a parent processing node in the above sub-network, the carrier signal is output to the parent processing node in the above network.

19. The method of claim 8, wherein if the destination address includes an address for a parent processing node in the above sub-network and an address for a current processing node, the carrier signal is output to the below sub-network or the child device.

20. The method of claim 8, wherein if the destination address includes an address for a parent processing node in the above sub-network and does not include an address for a current processing node, the carrier signal is output to another processing node in the same sub-network.

40. The method of claim 8, wherein the carrier signal is selected based on whether the communication signal is an express signal or a non-express signal.

42. The method of claim 40, wherein if the communication signal is an express signal, the carrier signal is output without the communication signal being processed.

21. A method of routing signals through a network, comprising:

receiving the signal at a first processing node;

passing a signal to a second processing node if the frequency or wavelength of the signal is not assigned to the first processing node; and

processing address information if the frequency or wavelength of the signal is assigned to the first processing node.

22. The method of claim 21, wherein the step of passing the signal to a second processing node further comprises passing the signal through a filter which directs signals of a first frequency or wavelength to a first output port, signals of a second frequency or wavelength to a second output port and signals of a third frequency or wavelength to a third output port.

23. The method of claim 22, wherein the first output port corresponds to a processing module of the first processing node, the second output port corresponds to an interface with processing nodes of a same sub-network, and the third output port corresponds to an interface with processing nodes of an above sub-network.

24. The method of claim 21, wherein the network is comprised of a plurality of layers and the step of processing address information further comprises:

reading a first address from a first address field of the address information, the first address field corresponding to a next higher layer in the network;

determining if the first address identifies a parent processing node; and

if the first address does not identify the parent processing node routing the signal to the parent processing node.

25. The method of claim 24, further comprising:

reading a second address from a second address field if the first address does identify the parent processing node;

determining if the second address identifies a current processing node; and

if the second address does not identify the current processing node, routing the signal to another processing node in the same sub-network.

26. The method of claim 25, further comprising:

reading a third address from a third address field if the second address does identify the current processing node; and

routing the signal to a processing node in a lower layer or a child device identified by the third address.

27. The method of claim 21, further comprising outputting a carrier signal to the second processing node in an above sub-network if the address information does not include an address for the second processing node.

28. The method of claim 21, further comprising outputting a carrier signal to the second processing node in a below sub-network or to a child device if the address information includes an address for a parent processing node and an address for the first processing node.

29. The method of claim 21, further comprising outputting a carrier signal to the second processing node in a same sub-network if the address information includes an address for a parent processing node and does not include an address for the first processing node.

41. The method of claim 21, further comprising passing the signal to the second processing node if the frequency or wavelength of the signal is an express frequency or wavelength.

43. The method of claim 41, wherein if the frequency or wavelength of the signal is an express frequency of wavelength, the signal is passed to the second processing node without processing address information.

30. A network, comprising:

a first layer of processing nodes; and

a second layer of processing nodes, wherein;

the processing nodes of each of the first and second layers are organized into sub-networks comprised of one or more processing nodes;

sub-networks of a same layer are not directly coupled to each other; and

at least one processing node of each sub-network of the second layer is coupled to a processing node of a sub-network in the first layer, unless the second layer is a top layer, and to at least one of a processing node of a sub-network in a third layer or a child device.

31. The network of claim 30, wherein the network is a telecommunications network.

39. The medium interface of claim 31, wherein the filter directs the signal based on whether the frequency or wavelength of the signal identifies the signal to be an express signal or a non-express signal.

32. A medium interface, comprising:

a filter;

at least three input ports; and

at least three output ports, wherein a signal is received through one of the at least three input ports and the filter directs the signal to one of the at least three output ports based on a frequency or wavelength of the signal.

33. The medium interface of claim 32, wherein the filter directs signals of a first frequency or wavelength to a first output port, signals of a second frequency or wavelength to a second output port and signals of a third frequency or wavelength to a third output port.

34. The medium interface of claim 33, wherein the first output port corresponds to a processing module of a first processing node, the second output port corresponds to an interface with processing nodes of a same sub-network, and the third output port corresponds to an interface with processing nodes of an above sub-network.

35. The medium interface of claim 32, wherein the filter includes one of a digital filter and an optical filter.

36. The medium interface of claim 32, wherein the filter includes at least one of a band pass filter, a low pass filter and a high pass filter.

37. The medium interface of claim 32, wherein the filter includes at least one of a dichroic mirror, a prism and an optical switch.

38. A processing node for routing a signal through a network comprised of a plurality of other processing nodes, comprising:

a medium interface; and

a processing module, wherein the medium interface receives the signal and, if the frequency or wavelength of the signal is not assigned to the processing node, the medium interface passes the signal to one of the plurality of other processing nodes and if the frequency or wavelength of the signal is assigned to the processing node, the medium interface passes the signal to the processing module for processing.