Adaptive weight factor estimation from user preferences for vertical handoff decision algorithms
- Authors: Sharna, Shusmita , Murshed, Manzur
- Date: 2011
- Type: Text , Conference paper
- Relation: IEEE Wireless Communications and Networking Conference (WCNC) (Mony de Swaan Adali 28 March 2011 to 31 March 2011) p. 1143-1148
- Full Text: false
- Reviewed:
- Description: Estimating weight factors for QoS parameters plays an important role in the effectiveness of vertical handoff decision algorithms. This paper presents a novel weight estimation technique, which can adaptively control the spanning of the weights in response to user preference. Simulation results show the supremacy of the technique against the state-of-the-art in achieving wider spanning of the expected values of all QoS parameters under consideration.
Call admission control policy for multiclass traffic in heterogeneous wireless networks
- Authors: Sharna, Shusmita , Amin, Mohammad , Murshed, Manzur
- Date: 2011
- Type: Text , Conference paper
- Relation: International Symposium on Communications and Information Technologies (ISCIT) p. 433-438
- Full Text: false
- Reviewed:
- Description: An increasing demand for wireless access to packetbased services has, in turn, driven the need for call admission control strategies to make network roaming more seamless. This paper investigates the optimal call admission control (CAC) policy for heterogeneous wireless networks based on Markov Decision Process (MDP) and Value Iteration Algorithm (VIA). We concentrate on the optimization problems of when different type of calls (i.e., new calls, vertical handoff calls, and horizontal handoff calls) can be admitted into the system where each call may have single or multiple channel requirements (multiclass). Experimental results confirm that the proposed technique can effectively control call admission of a highly dynamic heterogeneous system, which will be crucial for accommodating vertical handoff decision algorithms
Performance analysis of vertical handoff algorithms with QoS parameter differentiation
- Authors: Sharna, Shusmita , Murshed, Manzur
- Date: 2010
- Type: Text , Conference paper
- Relation: 12th IEEE International Conference on High Performance Computing and Communications p. 623-628
- Full Text: false
- Reviewed:
- Description: Despite recent interests in developing vertical handoff decision algorithms, an essential component of the architecture of the next generation heterogeneous wireless networks, very few studies have so far reported any meaningful comparative performance analysis. This paper attempts to fill this gap in the literature by presenting a comprehensive study on the performance of three vertical handoff decision algorithms, namely, SAW (Simple Additive Weighting), TOPSIS (Technique for Order Preference by Similarity to Ideal Solution), and MDP (Markov Decision Process). We have used both analytical and simulation tools (ns-2.29) to evaluate and compare expected total QoS offerings in the mean duration of a service under different state transition probability distributions, user perception models on the importance of QoS parameters, and network switching costs. To our surprise, we have observed TOPSIS achieving the best performance despite MDP's using the optimal policy. We suspect that the user satisfiability model used in MDP to estimate link rewards might have contradicted the underlying user perception model used to estimate normalised weight of each QoS parameter, which will be investigated in future.