160 likes | 403 Views
Performance Evaluation of the IEEE 802.16 MAC for QoS Support. Aemen Hassaan Lodhi 05060021. Outline . IEEE 802.16 (WiMAX) MAC layer Project Objective Simulation Environment Performance Metrics Work accomplished Future strategy. IEEE 802.16 (WiMAX).
E N D
Performance Evaluation of the IEEE 802.16 MAC for QoS Support Aemen Hassaan Lodhi 05060021
Outline • IEEE 802.16 (WiMAX) • MAC layer • Project Objective • Simulation Environment • Performance Metrics • Work accomplished • Future strategy
IEEE 802.16 (WiMAX) • Wireless MAN – provides network access to subscriber stations (SS) with radio base stations (BS) • Offers an alternative to cabled access networks – fiber optic links, coaxial cables using cable modems, DSL links • Supports nomadic and mobile clients on the go (IEEE 802.16 e, 2004)
MAC layer • Manage the resources of the air-link efficiently and provide Quality of Service (QoS) differentiation for different connections/streams • Supporting Point to Multipoint and Mesh network models • Performing Link Adaption & ARQ functions • Transmission Scheduling • Admission Control • Link Initialization • Fragmentation and Retransmission
Project Objective • Verify via simulation the ability of IEEE 802.16 MAC to handle multimedia traffic having stringent QoS requirements • Determine the best scheduling scheme provided by IEEE 802.16 for multimedia traffic • Simulations to be performed on NS-2
Scheduling Services provided by IEEE 802.16 MAC • Classification of applications based on the commonality of: • QoS service requirements (e.g. real time applications with stringent delay requirements, best effort service applications with minimum guaranteed bandwidth) • Packet arrival pattern (fixed/variable sized data packets at periodic/aperiodic intervals) • Mechanisms to send Bandwidth requests to the BS
Scheduling Services provided by IEEE 802.16 MAC • Unsolicited Grant Service – supports real-time applications with strict delay requirements with fixed sized data packets • Real-Time Polling Service – supports real time applications with less stringent delay requirements, generating variable sized data packets • Non-Real-Time Service – supports applications with no specific delay requirements, reserves a minimum amount of bandwidth • Best Effort Service – supports applications with no specific delay requirements – like the internet
Simulation Environment • NS 2 Simulator • PMP mode • Time Division Multiple Access mode for transmission from SSs to BS • Downlink and Uplink subframes duplexed using Frequency Division Duplex • Full Duplex Subscriber Stations
Traffic Models • Voice over IP traffic • Modeled as ON/OFF source with Voice Activity Detection (VAD) • Packets generated only during ON period • Duration of ON/OFF period distributed exponentially • Videoconference traffic • MPEG 4 video trace
Performance Evaluation • Affect of frame duration on delay • Performance comparison of RTPS with nRTPS when they coexist in the same SS • Change in delay with the number of SS • Analysis of simulation results • (More comparisons to be added)
Work accomplished • Literature survey • Set up of the simulator environment • Integration of the WiMAX module in the NS-2 simulator • WiMAX module obtained from Netowrks & Distributed Systems Laboratory (NDSL) members, Computer Science and Information Engineering, Chang Gung University, Taoyuan, Taiwan • “The Design and Implementation of WiMAX Module for NS-2 simulator” Proceedings from the 2006 workshop on ns-2: the IP network simulator WNS2 '06 ACM Press
Future Plan • Implementation the VoIP model • Using the video trace as a traffic source • Simulations • Analysis of Simulations
References 1. Claudio Cicconetti, Alessandro Erta, Luciano Lenzini, and Enzo Mingozzi, ‘Performance Evaluation of the IEEE 802.16 MAC for QoS Support’, IEEE Transactions on Mobile Computing, VOL. 6, No. 1, January 2007 2. Jenhui Chen, Chih-Chieh Wang, Frank Chee-Da Tsai§, Chiang-Wei Chang, Syao-Syuan Liu, Jhenjhong Guo, Wei-Jen Lien, Jui-Hsiang Sum, and Chih-Hsin Hung, ‘The Design and Implementation of WiMAX Module for ns-2 Simulator’, ACM International Conference Proceeding Series, Proceeding from the 2006 workshop on ns-2: the IP network simulator 3. F.H.P. Fitzek and M. Reisslein, “MPEG4 and H.263 Video Traces for Network Performance Evaluation,” IEEE Network Magazine, vol. 15, no. 6, pp. 40-54 Nov. 2001.