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SUMMARY:Optimizing Placement of Services for Real Time Communication - Phi
 lip A. Chou\, Microsoft
DTSTART:20130808T130000Z
DTEND:20130808T140000Z
UID:TALK46621@talks.cam.ac.uk
CONTACT:Microsoft Research Cambridge Talks Admins
DESCRIPTION:In a network\, the location of a service is inextricably linke
 d to the locations of the paths through which the service communicates.  H
 ence service location can have a profound effect on quality of service (Qo
 S) for communication-centric applications such as real-time multimedia.  W
 e propose an online algorithm that uses pricing to consider server load\, 
 route congestion\, and propagation delay jointly when locating servers and
  routes for real-time multimedia services in a network with fixed computin
 g and communication capacities.  The algorithm is online in the sense that
  it is able to sequentially allocate resources for services with long and 
 unknown duration as demands arrive\, without benefit of looking ahead to l
 ater demands.  By formulating the problem as one of lowest cost subgraph p
 acking\, we prove that our algorithm is nevertheless C-competitive with th
 e optimal algorithm that looks ahead\, meaning that our performance is wit
 hin a constant factor C of optimal\, as measured by the total number of se
 rvice demands satisfied\, or total user utility.  Using mixing services as
  an example\, we show through experimental results that our algorithm can 
 adapt to cross traffic and automatically route around congestion and failu
 re of nodes and edges\, can reduce latency by 40% or more\, and can pack 2
 0% more sessions or alternatively can double the number of sessions before
  significant call rejection\, compared to conventional approaches.
LOCATION:Auditorium\, Microsoft Research Ltd\, 21 Station Road\, Cambridge
 \, CB1 2FB
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