Application-aware policy enforcement
An application-aware policy enforcement point (PEP) attaches to the edge of a packet-switched network to manage loading when the network nears or exceeds its capacity due to changes in the network, e.g., component failures or incremental growth. An advanced bandwidth manager (ABM) comprises a session/call admission controller (S/CAC) that monitors and maps ever-changing network topology information gathered from remote listeners about how traffic is being routed through various parts of the network. These reports are harmonized to build a single view of the network topology, and the point-to-point connections are abstracted into path tables. Autonomous PEP's at the network's edges provide short-term, application-aware controls on their own that are applied to the corresponding network ingress traffic. The S/CAC uses the path tables to calculate whether particular PEP's can admit more traffic, or should they shed sessions/calls to keep service up for the existing application traffic. Long-term controls are periodically downloaded as admission tables from the S/CAC to the PEP's.
1. A policy enforcement point (PEP), comprising:
interfaces for attachment to an edge of a packet-switched network, and providing for autonomous short-term, application-aware controls applied to autonomously control admission of corresponding network ingress traffic at the PEP, and further providing for long-term traffic controls on said corresponding network ingress traffic, said interfaces configured to provide for autonomous short-term, application-aware controls and to provide for long-term traffic controls by:
receiving a new call or session at the PEP;
determining if enough resources are available for the new call or session at the PEP;
admitting the new call or session if the PEP determines that there are enough resources; and
requesting from a session/call admission controller (S/CAC) increased reservation resources if the PEP determines that there are not enough resources;
admission policies that prioritize application traffic and give priority admission to one traffic class over another; and
admission control tables downloadable from the session/call admission controller (S/CAC) independently located within the topology of said packet-switched network, and the PEP and the S/CAC use said packet-switched network to communicate with one another, and together Implement admission of said long-term traffic controls that differentiate between traffic classes.
2. The PEP of claim 1 , wherein:
said S/CAC includes a processor that calculates if the PEP may admit more, or must shed, sessions/calls to maintain service for other existing application traffic;
wherein, a traffic class that requires a greater amount of network resources can be shed for another traffic class that requires a lesser amount of network resources if an underlying application traffic can tolerate such reduction.
3. The PEP of claim 2 , wherein said processor operates to shed particular sessions/calls that are calculated to maintain service for the other existing application traffic that maximizes at least one of total revenues being earned, total number of calls remaining, and customer goodwill.
4. The PEP of claim 1 , wherein:
said S/CAC provides for downloading of updated admission tables to the PEP when it in particular is affected by a change in the packet-switched network topology or bandwidth reservation capacity.
5. The PEP of claim 1 , further comprising:
a negotiation process included with said S/CAC and the PEP to enable the PEP to request additional network resources, and for said S/CAC to communicate to the PEP that the request for additional network resources has been granted, and for the PEP to thereafter make local decisions to admit calls requiring said additional network resources.
6. The PEP of claim 5 , further comprising:
a bargaining process included with the S/CAC and the PEP to enable the PEP to request the additional network resources, and for said S/CAC to communicate to the PEP that the request for additional network resources can only be partially granted, and for the PEP to accept a partial grant of the additional network resources and thereafter make local decisions to admit calls that require only part of said additional network resources.
7. A method for admission control at a network edge, comprising:
attaching at least one policy enforcement point (PEP) to an edge of a packet-switched network, and providing for autonomous short-term, application-aware controls applied to autonomously control admission of corresponding network ingress traffic at the at least one PEP, and further providing for long-term controls on said corresponding network ingress traffic;
wherein providing for autonomous short-term, application aware controls and providing for long-term traffic controls comprises:
receiving a new call or session at the at least one PEP;
the at least one PEP determining if enough resources are available for the new call or session;
admitting the new call or session if the at least one PEP determines that there are enough resources; and
requesting from a session/call admission controller (S/CAC) increased reservation resources if the at least one PEP determines that there are not enough resources; and
managing network ingress traffic to said packet-switched network when the network ingress traffic nears or exceeds said packet-switched network capacity, and that is enabled to do so by computations of current network routing topology and bandwidth reservations;
wherein, admission policies prioritize application traffic and give priority admission to one traffic class over another; and
wherein, each of the PEP and a session/call admission controller (S/CAC) may be independently located within the topology of said packet-switched network, and each uses said packet-switched network to communicate with one another, and the at least one PEP and the S/CAC implement admission controls that differentiate between traffic classes.
8. The method of claim 7 , further comprising:
including a processor with the S/CAC that uses path tables to calculate if a PEP may admit more, or must shed, sessions/calls to maintain service for other existing application traffic.
9. The method of claim 8 , wherein said processor operates to shed particular sessions/calls that are calculated to maintain services for the other existing application traffic that maximizes at least one of total revenues being earned, total number of calls remaining, and customer goodwill.