Admission control and resource allocation in a communication system supporting application flows having quality of service requirements
A method and apparatus for admission control in a communication system. An Access Network (AN) element determines available resources. When available resources are sufficient to support the requirements of a requested application flow, the AN admits the application flow. The AN periodically, and on trigger events, updates a measure of available resources. The admission control may operate in coordination with a scheduler applying a compensation factor to each flow type, and a compensation factor for aggregate flows of a given user.
1. A method for admission control in a communication system supporting Internet Protocol (IP) applications, the communication system including an Access Network (AN) and a plurality of Access Terminals (ATs), each of the ATs sending a requested data rate to the AN, the communication system supporting application flows having QoS requirements to the ATs, the method comprising:
determining available resources in the communication system;
receiving a request for a first application flow having a first traffic profile and a first QoS profile;
determining if the available resources support the request for the first application flow;
denying the first application flow if the first application flow has a corresponding data rate greater than an average requested data rate; and
admitting the first application flow if the corresponding data rate is not greater than the average requested data rate, and if the available resources support the request for the first application flow,
wherein the method further comprises:
determining QoS statistics for the first application flow;
comparing the QoS statistics for the first application flow to other current flows in the sector; and
updating the available resources and reserved resources in response to comparing the QoS statistics for the first application flow to other current flows in the sector.
2. The method as in claim 1 , wherein determining if the available resources support the first application flow; comprises:
determining reserved resources in the communication system;
comparing the reserved resources to the capacity of the communication system; and
determining the available resources as the difference between the capacity and the reserved resources.
3. The method as in claim 2 , further comprising:
determining an adaptive subscription factor for the first application flow.
4. The method as in claim 3 , further comprising:
updating the adaptive subscription factor based on Quality of Service (QoS) statistics for the first application flow.
5. The method as in claim 1 , further comprising:
determining user presence of the first application flow in a sector of the wireless communication system; and
determining a sample duration for the first application flow,
wherein determining QoS statistics for the first application flow comprises:
determining QoS statistics for the first application flow during the sample duration.
6. The method as in claim 5 , wherein a first sample duration is associated with rate violations and a second sample duration is associated with delay violations.
7. The method as in claim 5 , wherein comparing the QoS statistics for the first application flow to other current flows in the sector comprises:
calculating a first fraction of slots used by flows having QoS requirements during the sample period;
calculating a second fraction of slots used by the first application flow during the sample period;
calculating a third fraction of QoS flows corresponding to a first QoS statistic;
comparing the third fraction to a corresponding threshold value; and
evaluating an adaptive subscription in response to comparing the third fraction to a corresponding threshold value.
8. An apparatus for admission control in a communication system supporting Internet Protocol (IP) applications, the communication system including an Access Network (AN) and a plurality of Access Terminals (ATs), each of the ATs sending a requested data rate to the AN, the communication system supporting application flows having QoS requirements to the ATs, the apparatus comprising:
means for determining available resources in the communication system;
means for receiving a request for a first application flow having a first traffic profile and a first QoS profile;
means for determining if the available resources support the request for the first application flow;
means for denying the first application flow if the first application flow has a corresponding data rate greater than an average requested data rate; and
means for admitting the first application flow if the corresponding data rate is not greater than the average requested data rate, and if the available resources support the request for the first application flow,
wherein the apparatus further comprises:
means for determining QoS statistics for the first application flow;
means for comparing the QoS statistics for the first application flow to other current flows in the sector; and
means for updating the available resources and reserved resources in response to comparing the QoS statistics for the first application flow to other current flows in the sector.
9. An apparatus adapted for admission control in a communication system, comprising:
at least one processor configured to:
determine available resources in the communication system;
receive a request for a first application flow having a first traffic profile and a first QoS profile;
determine if the available resources support the request for the first application flow;
deny the first application flow if the first application flow has a corresponding data rate greater than an average requested data rate; and
admit the first application flow if the corresponding data rate is not greater than the average requested data rate, and if the available resources support the request for the first application flow,
wherein the processor is further configured to:
determine QoS statistics for the first application flow;
compare the QoS statistics for the first application flow to other current flows in the sector; and
update the available resources and reserved resources in response to comparing the QoS statistics for the first application flow to other current flows in the sector.
10. The apparatus of claim 9 , further comprising at least one memory element configured to store instructions to be executed by the at least one processor.
11. A processor-readable medium encoded with processor-executable instructions for:
determining available resources in the communication system;
receiving a request for a first application flow having a first traffic profile and a first QoS profile;
determining determining if the available resources support the request for the first application flow;
denying the first application flow if the first application flow has a corresponding data rate greater than an average requested data rate; and
admitting the first application flow if the corresponding data rate is not greater than the average requested data rate, and if the available resources support the request for the first application flow,
wherein the processor-readable medium further comprises processor-executable instructions for:
determining QoS statistics for the first application flow;
comparing the QoS statistics for the first application flow to other current flows in the sector; and
updating the available resources and reserved resources in response to comparing the QoS statistics for the first application flow to other current flows in the sector.