Multi-staged services policing

1. A multi-staged services policer comprising:

one or more processors;

a downstream services policer;

a first upstream services policer to:

receive a traffic unit;

analyze said traffic unit;

based on said analysis, transmit said traffic unit to said downstream services policer; and

receive feedback from said downstream services policer; and

a second upstream services policer to transmit traffic units received at said second upstream services policer to said downstream services policer based on an analysis specific to said second upstream services policer,

wherein said downstream services policer is configured to afford a higher priority to traffic units received from said second upstream services policer than to traffic units received from said first upstream services policer.

2. The multi-staged services policer of claim 1 wherein said feedback from said downstream services policer is an indication of available bandwidth.

3. The multi-staged services policer of claim 1 wherein at least one of said services policers is configured to police at an application layer granularity.

4. The multi-staged services policer of claim 1 wherein at least one of said services policers is configured to police at a data link layer granularity.

5. The multi-staged services policer of claim 1 wherein said traffic unit is a Frame Relay frame.

6. The multi-staged services policer of claim 1 wherein said traffic unit is a Internet protocol packet.

7. A method of handling traffic units comprising:

receiving, by a first upstream services policer, a first traffic unit;

analyzing, by the first upstream services policer, said first traffic unit according to a first policy;

based on said analysis, transmitting, by the first upstream services policer, said first traffic unit to a downstream services policer;

processing, by the downstream services policer, the first traffic unit according to a second policy;

receiving, by the first upstream services policer, feedback from said downstream services policer to cause the first upstream services policer to modify analysis by the first upstream services policer of further received traffic units;

receiving a second traffic unit by a second upstream services policer;

analyzing, by the second upstream services policer, said second traffic unit according to a third policy;

based on said analysis of said second traffic unit, transmitting, by the second upstream services policer, said second traffic unit to the downstream services policer,

wherein said downstream services policer affords a higher priority to traffic units received from said second upstream services policer than to traffic units received from said first upstream services policer.

8. The method of claim 7 further comprising:

receiving, by the first upstream services policer, a third traffic unit;

analyzing, by the first upstream services policer, said third traffic unit differently from the analyzing of the first traffic unit in light of said feedback; and

based on said analysis of said third traffic unit, transmitting said third traffic unit to said downstream services policer.

9. A computer readable storage medium embodied with computer-executable instructions which, when executed by a processor in an upstream services policer that is upstream of a downstream services policer, cause the processor to:

receive a first traffic unit;

analyze said first traffic unit according to a first policy regarding processing of data traffic received by the upstream services policer;

based on said analysis, transmit said first traffic unit to said downstream services policer that processes data traffic received by said downstream services policer according to a second, different policy;

receive feedback from said downstream services policer;

receive a second traffic unit;

in response to the received feedback, analyze said second traffic unit differently from analysis of said first traffic unit; and

based on said analysis of said second traffic unit, transmit said second traffic unit to said downstream services policer.

10. A multi-staged services policer comprising:

one or more processors;

a first services policer to police traffic units according to a first policy for a first class of service;

a second services policer to police traffic units according to a second policy for a second class of service; and

a third services policer to receive output from each of said first services policer and said second services policer, wherein the third services policer is configured to afford a higher priority to traffic units received from the first services policer than to traffic units received from the second services policer.

11. The multi-staged services policer of claim 1 , wherein the first upstream services policer is to use the feedback from the downstream services policer to cause the first upstream services policer to modify analysis of further traffic units received by the first upstream services policer.

12. A multi-staged services policer comprising:

one or more processors;

a downstream services policer;

a first upstream services policer to:

receive a first traffic unit;

analyze said first traffic unit according to a first policy;

based on said analysis, transmit said first traffic unit to said downstream services policer; and

receive feedback from said downstream services policer, wherein the first upstream services policer is to use the feedback from the downstream services policer to cause the upstream services policer to modify analysis of further traffic units received by the upstream services policer; and

a second upstream services policer to receive second traffic units, analyze the second traffic units according to a second policy, and based on the analysis according to the second policy, transmit the second traffic units to the downstream services policer,

wherein the feedback received by the first upstream services policer from the downstream services policer is in response to receipt of the second traffic units from the second upstream services policer.

13. A multi-staged services policer comprising:

one or more processors;

a first downstream services policer; and

a first upstream services policer to:

receive a first traffic unit;

analyze said first traffic unit according to a first policy;

based on said analysis, transmit said first traffic unit to said first downstream services policer; and

receive feedback from said first downstream services policer;

a second upstream services policer to receive second traffic units, analyze the second traffic units according to a second policy, and based on the analysis of the second traffic units, transmit the second traffic units to the first downstream services policer;

a second downstream services policer; and

a third upstream services policer to receive third traffic units, analyze the third traffic units according to a third policy, and based on the analysis of the third traffic units, transmit the third traffic units to the second downstream services policer,

wherein the first, second, and third policies are for different types of traffic units.

14. The multi-staged services policer of claim 10 , wherein the third services policer is to send feedback information to the first services policer in response to the traffic units from the first services policer, wherein the first services policer is configured to respond to the feedback information by modifying analysis of further traffic units received by the first services policer.

15. The multi-staged services policer of claim 10 , wherein the third services policer is configured to send feedback information to the second services policer in response to traffic units received from the first services policer, wherein the second services policer is configured to modify analysis of further traffic units received by the second services policer in response to the feedback information.

16. The multi-staged services policer of claim 1 , wherein the downstream services policer includes a first of the processors, the first upstream services policer includes a second of the processors, and the second upstream services policer includes a third of the processors.

17. The multi-staged services policer of claim 1 , wherein the downstream and first and second upstream services policers are executable on the one or more processors.

18. The method of claim 7 , wherein each of the downstream services policer and first and second upstream services policers includes one or more processors.