IEEE 802.11 wireless LANs carrying integrated traffic quality of service policies and performance analysis

by Zaki, Maged

Wireless networking in the local environment is becorning increasingiy popular. IVirrlrss LXVs have seen deployment in factories. wuehouses and campus cnvironments. In the mean time. intemet has seen an unprecedented growth in the pst kw yeiirs. becoming the first "global" nrtwork. [ETF is working towards the definition of ,tlindiirds for the development of an Integrated Services ruid a Differentiated Services 1 DiffSén.) Internet. the object being to transform Lnternet, from a best effort service to a netkvork capable of providing some rom of QoS guaranties. The relrcommunications indusi- is working feverishly towards incorporating such standards in thrir products. It is only naturiil that WLAN environments should become capable of offering similar br.rviçrs. In ordcr to xhieve such a requirement in the wireless media. the design is c.xtrt.rnrly çompliciited. The unreliable physicai medium. hiddrn trrminals and the capture cifect considrr;ibly degrade the quality of the applications. Objective of this work is ro investigatc how Differentiated Services cm be accommodated in a WLAX cnvironment. The presrnt work deds with the EEE 802.1 1 standard. We rire addressing . & hoc and infrastructure network architectures. The impact of the presrnce of hidden rerniinirls ancl of the capture effect on the systrm performance protocol hiis bren in\.citigatcd. .-\ cornpuison betwern brhavior of the network undrr Poisson and Pareto Liirtrihution has bren perfurmrd. Performance rvaluations of integratrd vidro. voice and ciau traftic over a lEEE 802.1 1 wirelsss LAX have been conducted. The intluence, the huntinçss of WWW and file transfer traffic ha on the QoS parameters for real time applications. such as drlay and dropping rates has been evaluated. Scverd techniques rhat c m hr deployrd to iillow the "peaceful" CO-existence of different applications and prwidr the user with ;m acceptable lwel of quality have bren proposed. To my rnother with al1 my love