Controlling the age of information: Buffer size, deadline, and packet replacement
Clement Kam, Sastry Kompella, Gam D. Nguyen, Jeffrey E. Wieselthier, Anthony Ephremides · 2016
We study the age of information, which is a recently introduced metric for measuring the freshness of a continually updated piece of information as observed at a remote monitor. The age of information metric has been studied for a variety of different queuing systems, and in this work, we consider the impact of buffer sizes, packet deadlines, and packet replacement on the average age of information for queuing systems. We conduct a simulation-based study in which we modeled a wide variety of queuing systems and control mechanisms in simulation and computed the average age of information. We first study the buffer size alone to see how it affects the average age, and then we look at adding a packet deadline for such a system. We consider packet deadline control in the buffer only and in both the buffer and server, and we also compare the performance with a random deadline. We observe how the buffer size and deadline are optimized for the age, and we identify general trends for how to choose values of control mechanisms under different conditions of the packet generation rate. Lastly, we study the ability to replace packets in the buffer with newly arriving packets, and we are particularly interested in whether we can achieve the performance of such a system by controlling buffer size and deadline alone, for systems in which we do not have the ability to do packet replacement.