DYNAMICALLY ADAPTIVE BANDWIDTH ALLOCATION FOR HANDOFF MULTIMEDIA SERVICES FOR QUALITY OF SERVICE PERFORMANCE IN MOBILE CELLULAR NETWORKS

Abstract

With  the  tremendous  growth  of  multimedia  services  in  the  telecommunication  industry,  Quality  of  Service (QoS)  provisioning  is  becoming  more  important.  One  of  the  challenges  to  achieve  QoS  requirements  is  to determine  how  to  allocate  system  bandwidth  to  various  applications.  Moreover,  bandwidth  being  a  scarce resource,  it  should  be  used  efficiently.  One  way  of  achieving  this  is  to  adopt  micro/pico/femto -cellular architectures. A consequence  of using small cell sizes is the increased rate of call handoffs as mobile terminals move between cells. In a network supporting multimedia services, the increased rate of call handoffs not only increases the signaling load on the network, but also adverse ly affects the QoS.  To reduce handoff failures and achieve high bandwidth utilization an efficient multi- class adaptive bandwidth-allocation strategy that reclaims bandwidth from on-going calls is designed. Since a mathematical analysis of a real network  is difficult, proper simulations  are  preferred.  The  focus  for  this  paper  is  simulation  of  cellular  network  functionality  on  NS -2 integrated  with  EURANE.   In  this  simulation,  different  scenarios  have  been  designed  for  different  classes  of traffic and the performance is measured using parameters such as throughput and packet loss.   To analyze the result  of  the  simulation,  the  traffic  is  traced  during  the  process.  For  every  packet,  information  about  it  is written to a specified trace file.Primarily two scenarios are created. One is adaptive bandwidth allocation and
another  is  non-adaptive  bandwidth  allocation.  Different  sets  of  results  from  the  two  scenarios  give  us  the opportunity  to  investigate  the  performance  of  these  schemes.  The  investigation  illustrates  that  proper adaptation of bandwidth meets the QoS Requirements.

Key words: DiffServ, EURANE, NS-2, UTRAN, adaptive bandwidth allocation and non-adaptive bandwidth allocation