Transcript Performance Evaluation of the IEEE 802.16 MAC for QoS Support

Performance Evaluation of the
IEEE 802.16 MAC for QoS Support
Aemen Hassaan Lodhi
05060021
Outline
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IEEE 802.16 (WiMAX)
MAC layer
Project Objective
Simulation Environment
Performance Metrics
Work accomplished
Future strategy
IEEE 802.16 (WiMAX)
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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
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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
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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
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Classification of applications based on the
commonality of:
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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
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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
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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
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Voice over IP traffic
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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
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MPEG 4 video trace
Performance Evaluation
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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
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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
Simulator environment
Simulator Environment
Future Plan
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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.