Optimizing age-of-information in a multi-class queueing system

We consider the age-of-information in a multi-class M/G/1 queueing system, where each class generates packets containing status information. Age of information is a relatively new metric that measures the amount of time that elapsed between status updates, thus accounting for both the queueing delay and the delay between packet generation. This gives rise to a tradeoff between frequency of status updates, and queueing delay. In this paper, we study this tradeoff in a system with heterogenous users modeled as a multi-class M/G/1 queue. To this end, we derive the exact peak age-of-Information (PAoI) profile of the system, which measures the “freshness” of the status information. We then seek to optimize the age of information, by formulating the problem using quasiconvex optimization, and obtain structural properties of the optimal solution.National Basic Research Program of China (973 Program) (Grant 2011CBA00300)National Basic Research Program of China (973 Program) (Grant 2011CBA00301)National Natural Science Foundation (China) (Grant 61033001)National Natural Science Foundation (China) (Grant 61361136003)National Natural Science Foundation (China) (Grant 61303195)Tsinghua University (Beijing, China) (Initiative Research Grant)China Youth 1000-talent GrantNational Science Foundation (U.S.) (Grant CNS-1217048)United States. Office of Naval Research (N00014-12-1-0064