Method and apparatus for policing a QoS flow in a MoCA 2.0 network
Systems and methods for policing a Quality of Service (QoS) flow in a MoCA network are provided. The network may include a sending node, a receiving node and a network controller. The network controller may allocate a QoS flow between the sending node and the receiving node. The sending node may request bandwidth for the QoS flow from the network controller. QoS requests have a higher priority than some other requests and may swamp the network. The sending node therefore polices its use of the network. First, the sending node computes a policing time period Tpp. Next the sending node computes a packet and bit allocation for the use of the network during a Tpp. Last the sending node sends reservation requests to the network controller when the allocation of packet or bits has not been exceeded. If any allocation has been exceeded the sending node reserves bandwidth via opportunistic reservation requests which have a lower priority than some other requests.
1. A method of policing bandwidth usage in a home network, the network comprising a sending node, a receiving node and a network controller, wherein the sending node is connected to the receiving node, the method comprising:
computing a policing window;
computing a credit parameter;
initializing a usage parameter at the beginning of the policing window;
updating the usage parameter during the policing window;
sending a reservation request when the usage parameter is less than or equal to the credit parameter, wherein the reservation request is sent by the sending node to the network controller; and
sending an opportunistic reservation request when the usage parameter is greater than the credit parameter, wherein the opportunistic reservation request is sent by the sending node to the network controller.
2. The method of claim 1 , further comprising:
requesting from the network controller an allocation of a flow by the sending node; and
using the network controller to determine whether to refuse the allocation or to grant the allocation.
3. The method of claim 1 , wherein computing the policing window comprises:
determining whether a first flow parameter is set to a first particular value;
computing the policing window according to a first formula when the first flow parameter is not equal to the first particular value; and
computing the policing window according to a second formula when the first flow parameter is equal to the first particular value.
4. The method of claim 3 , wherein computing the policing window further comprises:
determining whether a second flow parameter is greater than a second particular value when the policing window is computed according to the first formula;
maintaining the policing window, which is computed according to the first formula, when the second flow parameter is not greater than the second particular value; and
changing the policing window, which is computed according to the first formula, by computing it according to the second formula when (a) the second flow parameter is greater than the second particular value and (b) the policing window computed according to the second formula is greater than the policing window computed according to the first formula.
5. The method of claim 3 , wherein the first formula is given by
P*S/R, where
P is based on a minimum duration to transmit, by the sending node to the receiving node, an integer number of packets,
S is a size of each of the packets, and
R is a peak data rate of the network.
6. The method of claim 5 , wherein P is the floor of a ratio of a maximum latency of a flow of the packets to a time to transmit one of the packets, and wherein P is greater than or equal to 1.
7. The method of claim 3 , wherein the second formula is given by
B*S/R, where
B is a maximum number of consecutive packets to be transmitted by the sending node to the receiving node,
S is a size of each of the packets, and
R is a peak data rate of the network.
8. The method of claim 1 , wherein computing the policing window further comprises adjusting the policing window to be greater than 2 milliseconds.
9. The method of claim 1 , wherein computing the policing window further comprises adjusting the policing window to be greater than an integer number of Media Access Plan cycles.
10. The method of claim 1 , wherein the credit parameter comprises the number of packets that can be sent within the policing window.
11. The method of claim 1 , wherein the credit parameter comprises the number of bits that can be sent within the policing window.
12. The method of claim 1 , wherein computing the policing window further comprises initializing the credit parameter.
13. The method of claim 1 , wherein the usage parameter is updated when one of a reservation request or an opportunistic reservation request is sent.
14. The method of claim 1 , further comprising reinitializing the credit parameter and the usage parameter when the policing window is complete.
15. A network comprising:
a sending node connected to a receiving node; and
a network controller;
wherein the sending node is configured to establish a flow to the receiving node,
wherein the sending node is configured to send a reservation request to the network controller when a usage parameter is less than or equal to a credit parameter and to send an opportunistic reservation request to the network controller when the usage parameter has exceeded the credit parameter.
16. The network of claim 15 , wherein the flow is a parameterized quality of service flow.
17. The network of claim 15 , wherein the sending node is configured to compute a policing window and to update a usage parameter within the policing window.
18. The network of claim 17 , wherein computing the policing window comprises:
determining whether a first flow parameter is set to a first particular value;
computing the policing window according to a first formula when the first flow parameter is not equal to the first particular value; and
computing the policing window according to a second formula when the first flow parameter is equal to the first particular value.
19. The network of claim 18 , wherein computing the policing window further comprises:
determining whether a second flow parameter is greater than a second particular value when the policing window is computed according to the first formula;
maintaining the policing window, which is computed according to the first formula, when the second flow parameter is not greater than the second particular value; and
changing the policing window, which is computed according to the first formula, by computing it according to the second formula when (a) the second flow parameter is greater than the second particular value and (b) the policing window computed according to the second formula is greater than the policing window computed according to the first formula.
20. The network of claim 17 , wherein computing the policing window further comprises adjusting the policing window to be greater than 2 milliseconds.
21. The network of claim 17 , wherein computing the policing window comprises adjusting the policing window to be greater than an integer number of Media Access Plan cycles.
22. The network of claim 17 , wherein the credit parameter comprises the number of packets that can be sent within the policing window.
23. The network of claim 17 , wherein the credit parameter comprises the number of bits that can be sent within the policing window.
24. The network of claim 17 , wherein computing the policing window further comprises initializing the credit parameter.
25. The network of claim 24 , wherein computing the policing window further comprises initializing the usage parameter.
26. The network of claim 25 , wherein the usage parameter is updated when one of a reservation request or an opportunistic reservation request is sent.
27. The network of claim 25 , wherein the sending node is configured to reinitialize the credit parameter and the usage parameter when the policing window is complete.
28. The network of claim 15 , wherein the sending node is configured to request an allocation of a flow from the network controller, and wherein the network controller is configured to determine whether to refuse the allocation or to grant the allocation.
29. A method of policing bandwidth usage in a home network, the network comprising a sending node, a receiving node and a network controller, wherein the sending node is connected to the receiving node, the method comprising:
computing a policing window;
computing a credit parameter;
initializing a usage parameter at the beginning of the policing window;
updating the usage parameter during the policing window;
requesting bandwidth that was granted to a data flow when the usage parameter is less than or equal to the credit parameter, wherein the bandwidth is requested by the sending node from the network controller; and
sending an opportunistic reservation request when the usage parameter is greater than the credit parameter, wherein the opportunistic reservation request is sent by the sending node to the network controller.
30. The method of claim 29 , wherein the network controller is configured to grant the opportunistic reservation request when sufficient bandwidth exists on the network.