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This research focuses on developing a dynamic and adaptive resource allocation strategy for wireless multimedia streaming services. It aims to optimize bandwidth utilization and guarantee call blocking probability during handovers. The study explores different wireless communication network methods and introduces the use of Markov Decision Processes (MDPs) for call admission control. Numerical results and conclusions are presented.
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Adaptive resource management with dynamic reallocation for layered multimedia on wireless mobile communication net work Date:2005/06/07 Student:Jia-Hao Xu Advisor:Kai-Wei Ke
Outline • Motivation • Background • Multimedia Streaming Service • Call admission Control for Single-Media • Call admission Control for Multimedia • Numerical Results • Conclusion
Motivation • We want to find an optimal call admission control policy for wireless multimedia streaming service. • Main issues: • To promote Wireless bandwidth resources utilization. • To guarantee handover call blocking probability.
Background • Wireless communication network introduction • Wireless resource allocation method • MDP (Markov Decision Process) introduction
Wireless Resource allocation method – 2G:GSM (Global System for Mobile) • It uses Frequency Division Multiple Access (FDMA) and Time Division Multiple Access (TDMA) to access air interface. • Divide carrier into multi TDMA frame (4.615ms) and each frame consist of eight time slots (577us). • It uses 51-Multiframe (51 TDMA frame).
Wireless Resource allocation method – 2G:GSM (Global System for Mobile) The unit of resources allocation is time slot.
Wireless Resource allocation method – 2.5G:GPRS (General Packet Radio Service) • The difference between GSM and GPRS is GPRS using 52-Multiframe (52 TDMA frame). • There are 4 IDLE frames and 12 Radio Blocks (each block contains 4 continuous frame).
Wireless Resource allocation method – 2.5G:GPRS (General Packet Radio Service) The unit of resources allocation is radio block.
Wireless Resource allocation method – 3G:WCDMA (Wideband Code Division Multiple Access) • It uses Code Division Multiple Access (CDMA) to access air interface and Direct Sequence Spreading Code (DSSC) modulation technique. • Each user allocate a orthogonal spreading code produced by OVSF Code (Orthogonal Variable Spreading Factor Code) technique. • The transmission depends on Spreading Factor.
Wireless Resource allocation method – 3G:WCDMA (OVSF Tree) The unit of resources allocation is SF (4~256).
MDP introduction • A Markov Decision Process is just like a Markov Process, except the transition depends on the action at each time step. • A system’s state has various options (actions) to choose from, and each option associates a “reward”. • The goal is to find a optimal policy, which specifies which action to take in each state, so as to maximize rewards. (solved by LP)
Outline • Motivation • Background • Multimedia Streaming Service • Call admission Control for Single-Media • Numerical Results • Conclusion
Streaming • Streaming is a process of playing a file while it is still downloading. And, it uses buffering techniques. • When a large media file (audio, video, etc.) is broken into smaller pieces so it can viewed or heard immediately. This avoids the wait for the whole file to be downloaded first. • It doesn’t require low delay but low jitter and media synchronization.
Multimedia application • There are many application using this technique, such as video phone, video-on-demand and interactive video games. • These services consume lots of bandwidth resources. • Layered encoding (multirate and adaptive): A technique to convert a file into a compressed, streaming format. For example, H.263, MPEG-2, and MPEG-4
Our streaming architecture System Web Select multimedia file Terminal user(traveler) Base station (do some things) Get file from streaming server Wireless transmission Return multimedia file Streaming server For example, adaptive and reallocation resources
Main issuse • Design a dynamic and adaptive resource allocation strategy to • Lower Blocking probabilitynew and handover call (especially) • Increase resources utilization
Outline • Motivation • Background • Multimedia Streaming Service • Call admission Control for Single-Media • Numerical Results • Conclusion
Base station Network model
Network model (cont.) • Each base station has a total of “C” bandwidth resources and support “k” different types of encoding method (means “k” different rates). • We assume that new arriving calls in a cell follow a Poisson process. • Both call session time and call dwell time are exponentially distributed and are independent from cells to cells
Three Strategies for • Adaptive Only • Adaptive and Dynamic Reallocation Finally • Adaptive and Dynamic Reallocation Anytime
Originating call Remaining resource ? YES Adaptive resource allocation NO New state Call blocked Adaptive Only (AO) -- X = (0,0) and call arrival => (1,0) or (0,1)
Call departure Resources release New state Adaptive Only (AO) --
Originating call Call blocked NO YES Remaining resource ? Resource reallocation NO YES Adaptive resource allocation New state Adaptive and Dynamic Reallocation Finally (ADRF) -- X = (1,2) => (0,3)or(1,2)or (2,1)or(3,0)
Call departure Resources release Resources reallocation New state Adaptive and Dynamic Reallocation Finally (ADRF) --
Originating call YES Resource reallocation NO Adaptive resource allocation Call blocked New state Adaptive and Dynamic Reallocation Anytime (ARDA) --
Call departure Resources release Resources reallocation New state Adaptive and Dynamic Reallocation Anytime (ARDA) --
Outline • Motivation • Background • Multimedia Streaming Service • Call admission Control for Single-Media • Numerical Results • Conclusion
Numerical results – Adjust handover blocking probability upper bound
Numerical results – Adjust handover blocking probability upper bound