788 research outputs found
Recommended from our members
A connection-level call admission control using genetic algorithm for MultiClass multimedia services in wireless networks
Call admission control in a wireless cell in a personal communication system (PCS) can be modeled as an M/M/C/C queuing system with m classes of users. Semi-Markov Decision Process (SMDP) can be used to optimize channel utilization with upper bounds on handoff blocking probabilities as Quality of Service constraints. However, this method is too time-consuming and therefore it fails when state space and action space are large. In this paper, we apply a genetic algorithm approach to address the situation when the SMDP approach fails. We code call admission control decisions as binary strings, where a value of “1” in the position i (i=1,…m) of a decision string stands for the decision of accepting a call in class-i; a value of “0” in the position i of the decision string stands for the decision of rejecting a call in class-i. The coded binary strings are feed into the genetic algorithm, and the resulting binary strings are founded to be near optimal call admission control decisions. Simulation results from the genetic algorithm are compared with the optimal solutions obtained from linear programming for the SMDP approach. The results reveal that the genetic algorithm approximates the optimal approach very well with less complexity
QoS management and control for an all-IP WiMAX network architecture: Design, implementation and evaluation
The IEEE 802.16 standard provides a specification for a fixed and mobile broadband wireless access system, offering high data rate transmission of multimedia services with different Quality-of-Service (QoS) requirements through the air interface. The WiMAX Forum, going beyond the air interface, defined an end-to-end WiMAX network architecture, based on an all-IP platform in order to complete the standards required for a commercial rollout of WiMAX as broadband wireless access solution. As the WiMAX network architecture is only a functional specification, this paper focuses on an innovative solution for an end-to-end WiMAX network architecture offering in compliance with the WiMAX Forum specification. To our best knowledge, this is the first WiMAX architecture built by a research consortium globally and was performed within the framework of the European IST project WEIRD (WiMAX Extension to Isolated Research Data networks). One of the principal features of our architecture is support for end-to-end QoS achieved by the integration of resource control in the WiMAX wireless link and the resource management in the wired domains in the network core. In this paper we present the architectural design of these QoS features in the overall WiMAX all-IP framework and their functional as well as performance evaluation. The presented results can safely be considered as unique and timely for any WiMAX system integrator
- …