Improving data freshness in random access channels

Atabay, Doğa Can
The conventional network performance metrics such as throughput and delay do not accurately reflect the needs of some applications. Age of information (AoI) is a newly proposed metric that indicates the freshness of information from the receiver’s perspective. In this work, a network of multiple transmitter devices continuously updating a central station over an error-free multiaccess channel is studied. The average AoI expressions are derived for Round-Robin, Slotted ALOHA, and a proposed random access strategy called LAZY. Optimal transmission rates are found for the two source network case with different threshold parameters under LAZY. It is proven that for the two source network, LAZY performs significantly better in terms of data freshness compared to the Slotted ALOHA due to the utilization of the instantaneous AoI knowledge of the sources.