AnalyticalModeling of Link and Path Dynamics and Their Implications on PacketLength in MANETs

摘要: Analytical Modeling of Link and Path Dynamics Their Implications on Packet Length in MANETs 1 Xianren Wu, Hamid R. Sadjadpour 1,2 J.J. Garcia-Luna-Aceves California at Santa Cruz, CA 95064, USA, email: {wuxr,hamid}@soe.ucsc.edu, tel: +1(831)459-1483 fax: +1(831)459-4829. 2 Palo Alto Research Center, 3333 Coyote Hill Road, Alto, 94304, jj@soe.ucsc.edu, +1(831)459-4153 University Keywords: dynamics, analytical mobility modeling, path lifetime, Markov model, optimal information segmentation ies routing-protocol performance have relied exclusively simulations, or had to use limited models link availability (e.g., [3]) address the dynamics paths impacting routing protocols [4]). This paper provides most accurate model behavior date, characterizes links as a function node mobility. The importance this is twofold. First, it enables in- vestigation many questions regarding fundamental tradeoffs throughput, delay storage requirements MANETs, well relationship between crosslayer-design choices packet length) network dynam- ics how long last MANET). Second, development new for channel access, clustering schemes by allowing such lifetime expressions that are with respect sim- ulations based widely-used models. Recently, Samar Wicker [5, 6] pioneered work evaluation dynamics. They further provided good insights an formulation optimization protocol design. However, assume communicating nodes maintain constant speed direction order evaluate distribution lifetime. simplification overlooks case which either changes its while transmission range each other. As result, results predicted Wicker’s could deviate from reality greatly, being overly conservative underestimating life- time 6], especially when ratio R/v radius communication R v becomes large, likely change their velocity during exchange. contribution provide two-state better describes behaviors nodes. Section 2. used characterize behavior. 3. proposed framework presents our 4. extends these Our approach two- state Markovian reflects movements inside circle builds accurately time. Abstract We present statistical wireless multi- hop mobile ad hoc networks (MANET). show lifetimes can be computed through solution fol- lows closely obtained discrete-event simu- lations two models, namely, random waypoint apply study practical implications proto- cols. compute lengths mo- bility, significant throughput improvements attained adapting bility MANET. INTRODUCTION (MANET) must cope frequent topology due characteristics radio channels. From standpoint medium access control (MAC) routing, channels trans- late into established among nodes, where typically assumed ex- ist able decode other’s transmis- sions. motivation that, critical MAC operating MANET, no exists to- day links, they form sources destinations, func- tion been analyzed ulations, modeling rout- ing not accounted tempo- ral nature MANET paths. For example, few developed multihop as- sumed static topologies [1]) focused immediate neighborhood node, remain neighbors duration exchanges [2]). Similarly, stud-