Sajal Saha

An efficient call admission control scheme on overlay networks using fuzzy logic

This paper proposes a call admission control (CAC) scheme for heterogeneous wireless overlay networks (WONs) that combine the benefits of the three commonly used techniques- guard channel, buffer management and priority scheduling with fuzzy logic application. The simulation results show that the scheme is extremely efficient offering a high degree of quality of service (QoS).

THMIP — A novel mobility management scheme using fluid flow model

In this paper we propose an improved hierarchy based mobility management scheme THMIP (Three-level Hierarchical Mobile IP) using fluid flow model to reduce the signaling overhead for a frequently moving mobile node (MN) within its hierarchical domain. In this scheme, the MN sends the binding update to the Home Agent (HA) only for the first time when the Care of address (CoA) gets changed. From the next movement onwards, it sends binding update to the previous Mobility Anchor Point (MAP). This results in reduction of cost both in Location Update and Packet Delivery. We compare our proposed protocol with other existing protocols such as Multi-Level HMIP, MIFA and P-MIP. We find that THMIP shows a considerable improved performance over the others in the context of Location Update and Packet Delivery.

Intelligent Paging Based Mobile User Tracking Using Fuzzy Logic

In general, a mobile user travels in a predefined path that depends mostly on the user’s characteristics. Thus, tracking the locations of a mobile user is one of the challenges for location management. In this paper, we introduce a movement pattern learning strategy system to track the user’s movements using adaptive fuzzy logic. Our fuzzy inference system extracts patterns from the historical data record of the cell numbers along with the date and time stamp of the users occupying the cell. Implementation of this strategy has been evaluated with the real time user data which proves the efficiency and accuracy of the model. This mechanism not only reduces user location tracking costs, but also significantly decreases the call‐loss rates and average paging delays.

Analysis of Hierarchical Mobile IP Based Fast Mobility Management Schemes

Mobility management in the wireless domain is a challenging issue for the next generation networks. Frequent change of network requires a new IP address to route packets from one host to another. It is done by sending the mobile node (MN) binding update to the Home Agent (HA) when the Care of address (CoA) gets changed. This registration requires large number of location updates, excessive signaling overhead and service delay. This problem is solved by Hierarchical Mobile IP (HMIP) protocol using the concept of hierarchy of Foreign Agent and the Gateway Foreign Agent /Mobility Anchor point to localize the registration information. This article presents an overview of set of HMIP based mobility protocols such as HMIP, PHMIP, RHMIP, DHMIP, FFHMIP, MIFA etc. that will play an important role in IP based mobility management. We analyze the advantages and disadvantages of theses protocols in the context of handoff latency and signaling overhead. Further, we propose a network model by removing the binding update with HA and simulate its performance in OPNET simulator. The simulation results show that our proposed mechanism achieve better performance than other protocols.

Optimized WiMAX Network Development in India: Specification and Implementation

WiMAX became popular due to simplicity of installation and cost reduction compared with traditional DSL cable. It is very important to provide Quality of Service (QoS) to end user to guarantee diversifying requirements of different applications in WiMAX. The system requirement of next-generation mobile WiMAX is supposed to be based on IEEE 802.16 m which is still in letter ballot stage specifically considering Indian environment. This paper presents an optimized architecture and scenario based on the recently standardized IEEE 802.16 m framework, integrating both mobility management and QoS in Indian scenario. Moreover, we analyse the QoS issues like throughput, uplink and downlink packet drop. OPNET-based simulation platform has been introduced for the verification of analytical model and results. The numerical results found in simulation can be used to select proper network configuration.

Performance analysis of service classes for IEEE 802.16m QoS optimization

Future generation of wireless mobile communication aims to provide high speed Internet access along with support for high mobility to the end users. Mobile WiMAX (IEEE 802.16e) has been developed in this direction in 2005 which provides broadband wireless Internet access up to 70Mbit/s. Its high speed enables various multimedia applications along with the conventional telephony service. These applications are categorized into classes like Platinum, Gold, Silver and Bronze according to their priority. In this paper we investigate the behavior of different scheduling algorithms for OFDMA/MIMO based WiMAX (IEEE 802.16m) architecture and analyze the quality of service (QoS) issues like throughput, end to end delay, interference, signal to noise ratio, call blocking probability and call dropping probability. For simulation, we used OPNET Modeler. The simulation results show high values of the QoS parameters although there is lack of consistency in some of those values that calls for further improvement in design, architecture and deployment strategy.

Performance analysis of a fuzzy logic based adaptive call admission control over heterogeneous wireless networks

This paper propose a novel call admission control (CAC) scheme that considers real-time and non-real-time nature of a call before allocating resources for its progress in a network. The scheme accumulates the benefits of different CAC schemes for best optimization of the available resources. It has combined the three major schemes- reserve guard channel, buffer based and prioritization. Application of fuzzy logic made the scheme adaptive by dynamic control of the threshold resource parameters using fuzzy logic. Simulation results show that the scheme outperforms the existing CAC schemes in terms of QoS.

An Analytical Model of Multi-service Call Admission Control in Next Generation Wireless Overlay Networks

This paper proposes a model for call admission control in the next generation wireless networks It presents a prioritized call admission procedure using the combination of buffer and guard channel schemes applicable to the heterogeneous networks in general and Wireless Overlay Network (WON) in particular Call admission priority is given to the real time calls over the non-real time calls which are classified in the network layer using unused bits of the IP header. Priority is also assigned to inter-layer (vertical) calls over intra-layer (horizontal) calls and handoff calls over new generated calls. A mathematical model using phase type distribution has been presented for analysis of the scheme using matrix generator method. The scheme assures quality of service (QoS) and smooth vertical handoff.

Mobile WiMAX Physical Layer Optimization and Performance Analysis Towards Sustainability and Ubiquity

Mobile WiMAX is emerging as a means for low cost reliable wireless broadband connection compared to traditional DSL cable. The system requirement of next generation mobile WiMAX is supposed to be based on IEEE 802.16 m which is still in letter ballot stage. This paper attempts to make in depth performance evaluation of Mobile WiMAX under various PHY parameters such as modulation and coding schemes (MCS), cyclic prefixes and different path-loss models. Moreover it also present an optimized adaptive modulation scheme that senses the SNR and adaptively switches to required MCS towards achieving the desired level of Quality of Service (QoS) and link stability. Simulation results show that dynamic adaptation of modulation and coding scheme based channel conditions can offer enhanced throughput, load, reduced delay, SNR and BER.

Performance analysis of the CAC scheme CARETON under mixed cell environment in overlay networks

The paper proposes a call admission control (CAC) scheme to offer best services to the users in the next generation heterogeneous networks. It optimises the available resources without compromising the interest of the service providers. It has combined the three commonly used CAC schemes – guard channel, buffer-based and priority-based schemes. It considers wireless overlay model for analysing the heterogeneity with detailed analysis of the WLAN-cellular mixed cell environment. The scheme considers differentiated services for the real time and non-real time calls to provide appropriate quality of service (QoS). The proposed scheme has been evaluated through simulation. The results show that the scheme outperforms some significant CAC schemes and shows even better performance under cellular-WLAN mixed environment due to the dual subscription of the users with dual mobile terminal.