Adaptive Scheduling mechanism for IPTV over WiMAX IEEE 802.16j Networks
Résumé
A WiMAX technology is a very promising Broadband Wireless Access technology that is able to transmit
different service types. This latter can have different constraints such as traffic rate, maximum latency, and
tolerated jitter. The IEEE 802.16 Medium Access Control specifies five types of QoS classes: UGS, rtPS,
ertPS, nrtPS, and BE. However, the IEEE 802.16 standard does not specify the scheduling algorithm to
be used. Operators have the choice among many existing scheduling techniques. Also, they can propose
their own scheduling algorithms. In this paper, we propose a scheduling strategy (AdaptiveWeighted Round
Robin, AWRR) for various Internet Protocol Television (IPTV) services traffic over 802.16j networks. Our
scheme adapts dynamically the scheduler operation to according queue load and quality of service constraints.
In particular, the proposed mechanism gives more priority to high definition television and standard
definition television traffic by using two schedulers. The proposed scheduling algorithm has been simulated
using the QualNet network simulator. The experimental results show that our scheduler schemes AWRR
have a better performance than the traditional scheduling techniques for rtPS traffic, which allows ensuring
QoS requirements for IPTV application