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Title: Updates with Multiple Service Classes
A source submits status update jobs to a service fa- cility for processing and delivery to a monitor. The status updates belong to service classes with different service requirements. We model the service requirements using a hyperexponential service time model. To avoid class-specific bias in the service process, the system implements an M/G/1/1 blocking queue; new arrivals are discarded if the server is busy. Using an age-of-information (AoI) metric to characterize timeliness of the updates, a stochastic hybrid system (SHS) approach is employed to derive the overall average AoI and the average AoI for each service class. We observe that both the overall AoI and class-specific AoI share a common penalty that is a function of the second moment of the average service time and they differ chiefly because of their different arrival rates. We show that each high-probability service class has an associated age-optimal update arrival rate while low- probability service classes incur an average age that is always decreasing in the update arrival rate.  more » « less
Award ID(s):
1717041
PAR ID:
10109355
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2019 IEEE International Symposium on Information Theory (ISIT)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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