Under-assigning resources to video in triple-play virtual topologies to protect data-class traffic
A method for video-on-demand (VoD) admission control at a network edge assigns to a triple-play network virtual topology lesser resources than there exists in a corresponding underlying physical link bandwidth. This prevents video-on-demand (VoD) starvation of data-class traffic. At least one policy enforcement point (PEP) is attached to an edge of the network, providing for autonomous short-term, application-aware controls to be applied to corresponding network ingress traffic, and also providing for long-term controls on corresponding network ingress traffic. The network ingress traffic to the network comes under management when the traffic nears or exceeds network capacity. It is enabled to do so by computations of current network routing topology and bandwidth reservations. Path tables are used to calculate if a PEP may admit more, or must shed, sessions/calls to maintain service for other existing application traffic. The PEP and a session/call admission controller (S/CAC) may be independently located within the topology of the network, and together implement admission controls that differentiate between triple-play video, voice, and data traffic classes.
1. A triple-play network, comprising:
a triple-play network virtual topology assigned lesser resources than resources available for traffic on an underlying physical link bandwidth to prevent starvation of data-class traffic by video-on-demand (VOD);
policy enforcement points (PEP's) for applying autonomous short-term, application-aware controls to autonomously control admission of corresponding network ingress traffic at each PEP, and applying long-term traffic controls on said corresponding network ingress traffic;
wherein applying autonomous short-term, application aware controls and applying long-term traffic controls comprises, for each PEP:
receiving a new call or session at the PEP;
the PEP determining if enough resources are available for the new call or session;
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 control tables received from the S/CAC for network admission need, wherein said admission control tables are updated when a network event results in a loss of resilient bandwidth that effects a traffic class under admission control, and when a surge in traffic exceeds a reserved resource in a PEP to a particular destination; and
the updated admission control tables for informing the PEP of network resources that are determined to be available to the PEP, wherein the updated admission control tables comprise recalculations of the network resources available across said triple play network that minimize adverse impacts on existing sessions and calls.
2. The network of claim 1 , further comprising:
a local priority drop scheme at each PEP to equally back off some traffic until total traffic is under a new limit if a new maximum exceeds a current utilization to a destination.
3. The network of claim 1 , further comprising:
a drop process to shed remaining calls until calls to a constrained destination are under a new limit.
4. The network of claim 1 , wherein:
if there is an unexpected surge in demand, the PEP's request additional resources to the particular destination;
wherein, said network is not affected by session or call admission, and changes to either admission policy or traffic engineering do not affect each other.
5. The network of claim 1 , further comprising:
a device for changing link capacity values to create and modify virtual topologies and afford policy control over the network's admission control.
6. The network of claim 1 , further comprising:
a device for allocating a portion of a physical topology to an application under admission control to make remaining bandwidth available for other applications.
7. The network of claim 1 , further comprising:
a topology monitor to extract topology information from the network for operator traffic engineering and operational support tools, to accurately address future needs and increase network reliability by providing accurate historic information to identify and solve long term problems.
8. The network of claim 1 , further comprising:
a device for calculating if the PEP may admit more, or must shed, session/calls to maintain service for other existing application traffic; and
a device for shedding particular sessions/calls in a way that is calculated to maintain service for existing application traffic and that maximizes at least one of total revenues being generated, total number of calls remaining, and customer goodwill.
9. The network of claim 1 , further comprising:
a device for downloading of the updated admission control tables to the PEP when it in particular is affected by a change in packet-switched network topology or bandwidth reservation capacity.
10. The network of claim 1 , further comprising:
a device for negotiating between 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 has been granted, and for the PEP to thereafter make local decisions to admit calls requiring said additional network resources.
11. The network of claim 1 , further comprising:
a device for bargaining between the 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 can only partially be granted, and for the PEP to accept a partial grant and thereafter make local decisions to admit calls that require only part of said additional network resources.
12. A method for video-on-demand (VOD) admission control at a triple-play network comprising:
assigning a triple-play network virtual topology lesser resources than resources available for traffic on a corresponding underlying physical link bandwidth to prevent starvation of data-class traffic by video-on-demand (VOD);
attaching at least one policy enforcement point (PEP) to an edge of said network, and providing for autonomous short-term, application-aware controls to autonomously control admission of corresponding network ingress traffic at the at least one PEP, and further providing for long-term traffic controls on said corresponding network ingress traffic;
wherein providing for autonomous short-term, application aware controls at the at least one PEP 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;
managing said corresponding network ingress traffic to said network when such nears or exceeds a capacity of said network, and that is enabled to do so by computations of current network routing topology and bandwidth reservations; and
using path tables to calculate if the at least one PEP may admit more, or must shed, sessions/calls to maintain service for other existing application traffic;
wherein each of the at least one PEP and the S/CAC are independently located within the topology of the network, and each uses said network to communicate with one another, and together implement admission controls that differentiate between traffic classes.