SYSTEM AND METHOD FOR PACKET TIMING OF CIRCUIT EMULATION SERVICES OVER NETWORKS

Abstract

A system and method for managing information communication in a network includes a plurality of network nodes. A plurality of circuit emulation data flows are established between a first network node and at least a second network node. Different data transmission rates are assigned to each circuit emulation data flow such that the frequency of communicated packets is different at least for each circuit emulation data flow used for timing recovery to make the plurality of circuit emulation data flows substantially independent of each other. For example, different frame rates can be assigned to synchronous backhaul transmission links such that the frequency of the backhaul transmission rates is substantially independent of the circuit emulation flow rates.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the present invention will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments, in conjunction with the accompanying drawings, wherein like reference numerals have been used to designate like elements, and wherein:

FIG. 1 is a diagram illustrating a system for managing information communication in a network, in accordance with an exemplary embodiment of the present invention.

FIG. 2 is a diagram illustrating a system for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 3 is a diagram illustrating a system for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 4 is a graph illustrating the time plot of packet delay jitter for four T1 circuit emulation services, when these services are all correlated and running at 32 frames per packet or 4 ms per packet.

FIG. 5 is a plot illustrating the probability distribution function corresponding to the graph illustrated in FIG. 4.

FIG. 6 is a graph illustrating the impact of making each of the circuit emulation flows of FIG. 4 independent of each other, in accordance with an exemplary embodiment of the present invention.

FIG. 7 is a plot illustrating the probability distribution function corresponding to the graph illustrated in FIG. 6, in accordance with an exemplary embodiment of the present invention.

FIG. 8 is a flowchart illustrating steps for managing information communication in a network, in accordance with an exemplary embodiment of the present invention.

FIG. 9 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 10 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 11 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 12 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 13 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 14 is a flowchart illustrating steps for managing information communication in a network, in accordance with an alternative exemplary embodiment of the present invention.

FIG. 15 is a histogram illustrating the time plot of packet delay jitter for WiMAX in the case of a 2.50 ms frame rate.

FIG. 16 is a histogram illustrating the time plot of packet delay jitter for WiMAX after making each of the circuit emulation flows of FIG. 14 orthogonal in frequency to the WiMAX frame rate of 2.510 ms, in accordance with an exemplary embodiment of the present invention.

Claims

1. A system for managing information communication in a network, comprising: a plurality of network nodes, wherein a plurality of circuit emulation data flows are established between a first network node and at least a second network node, andwherein different data transmission rates are assigned to each circuit emulation data flow such that the frequency of communicated packets is different at least for each circuit emulation data flow used for timing recovery to make the plurality of circuit emulation data flows substantially independent of each other.

2. A system for managing information communication in a network, comprising: a plurality of network nodes, wherein a circuit emulation data flow is established between a first network node and a second network node,wherein the circuit emulation data flow comprises a transmit data flow and a receive data flow, andwherein a first data transmission rate is assigned to the transmit data flow and a second data transmission rate is assigned to the receive data flow such that the transmit data flow at the first data transmission rate is substantially independent of the receive data flow at the second data transmission rate.

3. The system of claim 2, wherein the first data transmission rate and the second data transmission rate are substantially identical.

4. The system of claim 3, wherein at least one of the network nodes comprises a timing recovery module configured to compensate for nonlinear jitter variations resulting from beating of the transmit and receive data flows.

5. The system of claim 2, comprising: a management module in communication with the plurality of network nodes, wherein the management module is configured to monitor and control the first and second data transmission rates to ensure that the transmit data flow and the receive data flow are substantially independent of each other.

6. The system of claim 5, wherein the management module is configured to monitor and control the first and second data transmission rates to ensure that the transmit and receive data flows are substantially independent of one of synchronous time division duplexing (TDD) backhaul links, synchronous frequency division duplexing (FDD) backhaul links, and combined TDD/FDD backhaul links.

7. The system of claim 2, wherein the network comprises a wireless mesh network.

8. A system for managing communication of information in a network, comprising: a plurality of network nodes, wherein a plurality of circuit emulation data flows are established between a first network node and at least a second network node,wherein a substantially identical data transmission rate is assigned to each circuit emulation data flow,wherein a quantity of frames of data in each transmission is varied to modulate an amount of data transmitted in each circuit emulation data flow such that the plurality of circuit emulation data flows are substantially independent of each other, andwherein an average of the quantity of frames of data transmitted in each circuit emulation data flow is substantially equal to the data transmission rate.

9. The system of claim 8, wherein the amount of data transmitted in at least one circuit emulation data flow is modulated using a saw wave modulation.

10. The system of claim 8, wherein the amount of data transmitted in at least one circuit emulation data flow is modulated using a Gaussian modulation.

11. The system of claim 8, wherein the amount of data transmitted in at least one circuit emulation data flow is modulated using a sinusoidal modulation.

12. The system of claim 8, comprising: a management module in communication with the plurality of network nodes, wherein the management module is configured to monitor and control the quantity of frames of data in each transmission to ensure that the plurality of circuit emulation data flows are substantially independent of each other.

13. The system of claim 8, wherein the network comprises a wireless mesh network.

14. A system for managing communication of information in a network, comprising: a plurality of network nodes, wherein a plurality of circuit emulation data flows are established between a first network node and at least a second network node,wherein each of a plurality of predetermined circuit emulation frame rates is assigned to each of the plurality of circuit emulation data flows, andwherein a second frame rate, different than each of the predetermined circuit emulation frame rates, is assigned to backhaul links between network nodes such that the second frame rate is substantially independent of each of the plurality of predetermined circuit emulation frame rates.

15. The system of claim 14, wherein the second frame rate is substantially independent of each of the plurality of predetermined circuit emulation frame rates to mitigate non-linearities in jitter variations of the plurality of circuit emulation data flows.

16. The system of claim 14, wherein each of the plurality of predetermined circuit emulation frame rates comprises a different data transmission rate such that the frequency of communicated packets is different for each circuit emulation data flow to make each of the plurality of circuit emulation data flows substantially independent of each other.

17. The system of claim 14, wherein the backhaul links comprise WiMax backhaul links.

18. The system of claim 17, wherein the WiMax backhaul links comprise time division duplexing WiMax backhaul links.

19. The system of claim 14, wherein the network comprises a wireless mesh network.

20. A method of managing information communication in a network, comprising the steps of: a.) establishing a plurality of circuit emulation data flows between a first network node and at least a second network node; andb.) assigning different data transmission rates to each circuit emulation data flow such that the frequency of communicated packets is different at least for each circuit emulation data flow used for timing recovery to make the plurality of circuit emulation data flows substantially independent of each other.

21. A method of managing information communication in a network, comprising the steps of: a.) establishing a circuit emulation data flow between a first network node and a second network node, wherein the circuit emulation data flow comprises a transmit data flow and a receive data flow; andb.) assigning a first data transmission rate to the transmit data flow and a second data transmission rate to the receive data flow such that the transmit data flow at the first data transmission rate is substantially independent of the receive data flow at the second data transmission rate.

22. The method of claim 21, wherein the first data transmission rate and the second data transmission rate are substantially identical.

23. The method of claim 22, comprising the step of: c.) compensating for non-linear jitter variations resulting from beating of the transmit and receive data flows.

24. The method of claim 21, comprising the step of: c.) controlling the first and second data transmission rates to ensure that the transmit data flow and the receive data flow are substantially independent of each other.

25. The method of claim 24, wherein step (c) comprises the step of: c1.) controlling the first and second data transmission rates to ensure that the transmit and receive data flows are substantially independent of one of synchronous time division duplexing (TDD) backhaul links, synchronous frequency division duplexing (FDD) backhaul links, and combined TDD/FDD backhaul links.

26. The method of claim 21, wherein the network comprises a wireless mesh network.

27. A method of managing communication of information in a network, comprising the steps of: a.) establishing a plurality of circuit emulation data flows between a first network node and at least a second network node, wherein a substantially identical data transmission rate is assigned to each circuit emulation data flow; andb.) varying a quantity of frames of data in each transmission to modulate an amount of data transmitted in each circuit emulation data flow such that the plurality of circuit emulation data flows are substantially independent of each other, wherein an average of the quantity of frames of data transmitted in each circuit emulation data flow is substantially equal to the data transmission rate.

28. The method of claim 27, wherein step (b) comprises the step of: b1.) saw-wave modulating the amount of data transmitted in at least one circuit emulation data flow.

29. The method of claim 27, wherein step (b) comprises the step of: b1.) Gaussian modulating the amount of data transmitted in at least one circuit emulation data flow.

30. The method of claim 27, wherein step (b) comprises the step of: b1.) sinusoidally modulating the amount of data transmitted in at least one circuit emulation data flow.

31. The method of claim 27, comprising the step of: c.) controlling the quantity of frames of data in each transmission to ensure that the plurality of circuit emulation data flows are substantially independent of each other.

32. The method of claim 27, wherein the network comprises a wireless mesh network.

33. A method of managing communication of information in a network, comprising the steps of: a.) establishing a plurality of circuit emulation data flows between a first network node and at least a second network node;b.) assigning each of a plurality of predetermined circuit emulation frame rates to each of the plurality of circuit emulation data flows; andc.) assigning a second frame rate, different than each of the predetermined circuit emulation frame rates, to backhaul links between network nodes such that the second frame rate is substantially independent of each of the plurality of predetermined circuit emulation frame rates.

34. The method of claim 33, wherein the second frame rate is substantially independent of each of the plurality of predetermined circuit emulation frame rates to mitigate non-linearities in jitter variations of the plurality of circuit emulation data flows.

35. The method of claim 33, wherein each of the plurality of predetermined circuit emulation frame rates comprises a different data transmission rate such that the frequency of communicated packets is different for each circuit emulation data flow to make each of the plurality of circuit emulation data flows substantially independent of each other.