**** Columbia Network Research Group Seminar ****

Title:    Fast and Robust Signaling Overload Control
Speaker:  Dr. Sneha Kasera
          Lucent
When:     Wednesday, November 7, 2001, 2 pm
Where:    Interschool Lab, 7th Floor CEPSR
          Columbia University
Host:     Prof. D. Rubenstein


ABSTRACT

   Telecommunications switches implement overload controls to maintain
   call throughput and delay at acceptable levels during periods of high
   load.  Existing work has mostly focused on controls under sustained
   overload - they do not meet the demands of modern telecommunication
   systems where the increased number of services and mobile subscribers
   often creates fast changing hot spots.  We introduce a new algorithm
   that is designed to be highly reactive to sudden bursts of load.

   Our algorithm uses two measures:  call acceptance rate and processor
   occupancy.  Using simulations of realistic system models, we compare
   this algorithm with an existing algorithm that uses processor
   occupancy only.  We also compare our algorithm with a modified
   version of RED.  Our simulation results and qualitative arguments
   show that the combination of acceptance rate and processor occupancy
   results in a highly reactive and robust signaling overload control.

   We are currently studying the applicability of our acceptance
   rate-occupancy algorithm to router active queue management.  We will
   present some preliminary results from this study.