Feasibility Study on Control of Applications when Third party Servers encounter difficulties
With the spread of applications on UEs (also known as "smart phones"), coupled with the rapidly growing number of UEs designed for usage with little or no human involvement (machine type communications), the potential for issues to occur in the overall "system" involving these applications and the third party entities they interact with increases. When these third party entities experience difficulties, they may be able to manage their problems without undue impact on operator networks, but there will be times when they are not able to do so.
When a third party server becomes congested or fails, the communication by the UE applications that make use of that server need to be controlled so that excessive use of 3GPP network resources is avoided while not affecting other applications and their associated servers that are functioning normally.
The 3GPP network needs to be able to detect or receive an indication from a third party server of its congestion status or failure status and control UE applications (or their traffic in the 3GPP network) that make use of a third party server that has encountered difficulties. HTTP and other third party (possibly proprietary) protocols can have status codes but these can be insufficient as they cannot provide a suitable indication to the UE application of the nature of the issue and therefore could result in frequent retries even when these will fail, thus burdening the network with connection attempts that will fail.
The present document identifies potential requirements that will enable the 3GPP network to detect or receive an indication from a third party server of its congestion status or failure status and control the traffic of individual UE applications (or their traffic in the 3GPP network) when the 3GPP network becomes aware that a third party server has run into difficulties. This will make it possible to
- Reduce or avoid unproductive traffic in 3GPP network (i.e., traffic that the 3rd party server is not able to receive) by blocking it either in the UE or in the 3GPP network (primary objective)
- Allow 3GPP network to help 3rd party servers to handle overload and recover from failures (secondary objective)