Methods and devices for providing a self-stretching policer
An example method for providing a self-stretching policer in a Quality of Service (QoS) community including a root node and one or more agent nodes can include maintaining and enforcing a policer policy in the root node. The policer policy can include at least one packet classification rule and corresponding police action, and the policer policy can be enforced by taking the corresponding police action if a traffic flow violates the packet classification rule. The method can include collecting policer statistics and determining if the traffic flow violates the packet classification rule by greater than a predetermined threshold using the policer statistics. If the traffic flow violates the packet classification rule by greater than the predetermined threshold, the method can include transmitting the policer policy to one or more of the agent nodes.
1. A method for providing a self-stretching policer in a Quality of Service (QoS) community including a root node and one or more agent nodes, wherein the self-stretching policer dynamically stretches and withdraws the scope of the policer in the QoS community, the method comprising:
maintaining a policer policy in the root node, the policer policy including at least one packet classification rule and corresponding police action;
enforcing the policer policy in the root node by taking the corresponding police action if a traffic flow violates the packet classification rule; collecting policer statistics;
determining if the traffic flow violates the packet classification rule by being greater than a predetermined threshold based on the collected policer statistics; and
if a metric associated with the traffic flow violates the packet classification rule by being greater than the predetermined threshold, transmitting from the root node the policer policy, via one or more policer policy messages, to one or more of the agent nodes, including a given agent node adjacent and upstream to the root node from which the traffic flow is directed, wherein the transmitted policer policy message causes the given agent node to take corresponding police action if a traffic flow, including a short-duration burst traffic, received thereat, violates the packet classification rule of the policer policy message, and wherein the one or more transmitted policer policy messages cause the packet classification rule associated therewith to be dynamically stretched to and withdrawn from each of the one or more agent nodes that received a given policer policy message.
2. The method of claim 1 , wherein the policer policy is installed on at least one of the one or more agent nodes.
3. The method of claim 1 , wherein collecting policer statistics further comprises:
maintaining an in-profile metric related to packets of the traffic flow that do not violate the packet classification rule; and
maintaining an out-of-profile metric related to packets of the traffic flow that violate the packet classification rule.
4. The method of claim 3 , wherein determining if a metric associated with the traffic flow violates the packet classification rule by being greater than a predetermined threshold further comprises determining whether
the
out
-
of
-
profile
metric
(
the
in
-
profile
metric
+
the
out
-
of
-
profile
metric
)
>
the
predetermined
threshold
.
5. The method of claim 1 , further comprising:
identifying a source of the traffic flow that violates the packet classification rule by being greater than the predetermined threshold;
selecting at least one upstream agent node arranged between the source of the traffic flow and the root node; and
transmitting the policer policy to the upstream agent node.
6. The method of claim 1 , wherein transmitting the policer policy to one or more of the agent nodes further comprises transmitting a message comprising the packet classification rule, the corresponding police action and an enforcement period, wherein the policer policy is enforced by the one or more agent nodes during the enforcement period.
7. The method of claim 6 , further comprising transmitting a refresh message to one or more of the agent nodes to extend the enforcement period.
8. The method of claim 1 , further comprising transmitting a delete message to one or more of the agent nodes to cancel the policer policy.
9. A non-transitory computer readable storage medium having computer-executable instructions stored thereon for providing a self-stretching policer in a Quality of Service (QoS) community including a root node and one or more agent nodes that, when executed by the root node, cause the root node to:
maintain a policer policy including at least one packet classification rule and corresponding police action;
enforce the policer policy by taking the corresponding police action if a traffic flow violates the packet classification rule;
collect policer statistics;
determine if the traffic flow violates the packet classification rule by being greater than a predetermined threshold based on the collected policer statistics; and
if a metric associated with the traffic flow violates the packet classification rule by being greater than the predetermined threshold, transmit the policer policy, via one or more policer policy messages, to one or more of the agent nodes, including a given agent node adjacent and upstream to the root node from which the traffic flow is directed, wherein the transmitted policer policy message causes the given agent node to take corresponding police action if a traffic flow, including a short-duration burst traffic, received thereat, violates the packet classification rule of the policer policy message, and wherein the one or more transmitted policer policy messages cause the packet classification rule associated therewith to be dynamically stretched to and withdrawn from each of the one or more agent nodes that received a given policer policy message.
10. The non-transitory computer readable storage medium of claim 9 , wherein the instructions for collecting policer statistics comprise instructions, when executed by the root node, cause the root node to:
maintain an in-profile metric related to packets of the traffic flow that do not violate the packet classification rule; and
maintain an out-of-profile metric related to packets of the traffic flow that violate the packet classification rule.
11. The non-transitory computer readable storage medium of claim 10 , wherein the instruction for determining if a metric associated with the traffic flow violates the packet classification rule by being greater than a predetermined threshold comprise instructions, when executed by the root node, cause the root node to determine whether
the
out
-
of
-
profile
metric
(
the
in
-
profile
metric
+
the
out
-
of
-
profile
metric
)
>
the
predetermined
threshold
.
12. The non-transitory computer readable storage medium of claim 9 , having further computer-executable instructions stored thereon that, when executed by the root node, cause the root node to:
identify a source of the traffic flow that violates the packet classification rule by being greater than the predetermined threshold;
select at least one upstream agent node arranged between the source of the traffic flow and the root node; and
transmit the policer policy to the upstream agent node.
13. The non-transitory computer readable storage medium of claim 9 , wherein the instructions for transmitting the policer policy to one or more of the agent nodes comprise instructions, when executed by the root node, cause the root node to transmit a message comprising the packet classification rule, the corresponding police action and an enforcement period, wherein the policer policy is enforced by the one or more agent nodes during the enforcement period.
14. The non-transitory computer readable storage medium of claim 13 , having further computer-executable instructions stored thereon that, when executed by the root node, cause the root node to transmit a refresh message to one or more of the agent nodes to extend the enforcement period.
15. The non-transitory computer readable storage medium of claim 9 , having further computer-executable instructions stored thereon that, when executed by the root node, cause the root node to transmit a delete message to one or more of the agent nodes to cancel the policer policy.
16. A packet-forwarding node for providing a self-stretching policer in a Quality of Service (QoS) community, comprising:
a processing unit; and
a memory operably coupled to the processing unit, the memory having computer-executable instructions stored thereon that, when executed by the processing unit, cause the packet-forwarding node to:
maintain a policer policy including at least one packet classification rule and corresponding police action;
enforce the policer policy by taking the corresponding police action if a traffic flow that violates the packet classification rule;
collect policer statistics;
determine if the traffic flow violates the packet classification rule by being greater than a predetermined threshold based on the collected policer statistics; and
if a metric associated with the traffic flow violates the packet classification rule by being greater than the predetermined threshold, transmit the policer policy to one or more agent nodes in the QoS community, including a given agent node adjacent and upstream to the packet-forwarding node from which the traffic flow is directed, wherein the transmitted policer policy message causes the given agent node to take corresponding police action if a traffic flow, including a short-duration burst traffic, received thereat, violates the packet classification rule of the policer policy message, and wherein the one or more transmitted policer policy messages cause the packet classification rule associated therewith to be dynamically stretched to and withdrawn from each of the one or more agent nodes that received a given policer policy message.
17. The packet-forwarding node of claim 16 , wherein the instructions for collecting policer statistics comprises instructions, when executed by the root node, cause the root node to:
maintain an in-profile metric related to packets of the traffic flow that do not violate the packet classification rule; and
maintain an out-of-profile metric related to packets of the traffic flow that violate the packet classification rule.
18. The packet-forwarding node of claim 17 , wherein the instruction for determining if a metric associated with the traffic flow violates the packet classification rule by being greater than a predetermined threshold comprise instructions, when executed by the root node, cause the root node to determine whether to determine whether
the
out
-
of
-
profile
metric
(
the
in
-
profile
metric
+
the
out
-
of
-
profile
metric
)
>
the
predetermined
threshold
.
19. The packet-forwarding node of claim 16 , wherein the memory has further computer-executable instructions stored thereon that, when executed by the processing unit, cause the packet-forwarding node to:
identify a source of the traffic flow that violates the packet classification rule by being greater than the predetermined threshold;
select at least one upstream agent node arranged between the source of the traffic flow and the packet-forwarding node; and
transmit the policer policy to the upstream agent node.
20. The packet-forwarding node of claim 16 , wherein transmitting the policer policy to one or more of the agent nodes further comprises transmitting a message comprising the packet classification rule, the corresponding police action and an enforcement period, wherein the policer policy is enforced by the one or more agent nodes during the enforcement period.