Mobile Web Insights - Idle Devices Impact the Network

by Mayur Pitamber, Product Marketing Strategist

The iPhone is frequently the focus of our attention when it comes to mobile traffic analysis. While they still represent a small percentage of total devices on any operator's network, studying iPhones is a great way to glimpse the future of mobile behavior and its possible impact on mobile networks. More and more iPhones (and similar "superphones") get added to the network, and those that buy iPhones tend to spend more time using data services. Isolating these data-intensive devices helps us recognize small challenges before they become much larger and more difficult to solve.

Three of the top four devices (in terms of sessions per user per day ) on Operator X's network are iPhones. Digging a little deeper, it appears that the high number of iPhone sessions are the result of the device keeping the data sessions (technically called the PDP Context) open even when the device is idle. More open PDP Contexts result in additional network traffic which adds to network congestion. They also contribute to a shorter battery life – a common complaint of iPhones users.

One suggestion would be to optimize the data generated from the iPhones which would increase limited radio capacity thus increasing network throughput and decreasing congestion. Secondly, the TCP (transmission control protocol) buffer size in the core data network can be increased in order to handle the frequent bursts of data traffic during network congestion. Both of these options will limited network delays and improve the user experience, but only the next technique will do both and help extend battery life.

Since the PDP context can be initiated by the device or the network, Operator X could make some minor network configuration changes which would allow the network to automatically close PDP Contexts on select devices (in this case, iPhones) that have been idle for two minutes. The benefits would be immediate: less data traffic from open sessions and improved battery life on the devices.

One of the reasons why the iPhone keeps the PDP Context open, is to ensure a seamless user experience. It's how the weather widget maintains current information and how the Safari browser connects instantaneously to the network. Therefore, it would be in Operator X's best interests to disclose the configuration changes or offer them as opt in with the longer battery life as an incentive.

The above is based on four days of recent data from "Operator X," a tier-one European mobile network operator with approximately 10 million subscribers.

Mobile Web Insights is our ongoing look at real trends from real customer data. Our first three reports are also available for download.