Age-of-Information in Practice: Status Age Measured Over TCP/IP Connections Through WiFi, Ethernet and LTE

The Age of Information (AoI) has gained importance as a Key Performance Indicator (KPI) measuring freshness of information in information-update systems and time-critical applications. Almost all the previous literature on AoI has been theoretical. Most of these theoretical studies assumed knowledge of the statistics of network delays and/or link service times. However, in real-life networks, various factors contribute to these parameters, resulting in a complicated effect on age. This paper reports the results of a real-life implementation measuring the variation of AoI over TCP/IP links served by WiFi, LTE, 3G, 2G and Ethernet for different rates of status update generation by an application running over the Internet.