Trustworthy Local Breakout

Abstract

The newer generations of mobile networks (e.g., fifth generation) provide increasingly lower latencies in the home operator’s (HO’s) network, and there is similar expectation from subscribers while roaming. Moreover, regulations, like the EU’s Roam Like At Home, mandate that the roaming subscribers receive comparable service quality without additional charge from the visited operator (VO) in the roaming country. However, the currently most widely adopted roaming approach, home routed, adds significant latency because the roaming traffic traverses all the way back to the HO, while with local breakout, the subscriber is served locally by the VO, resulting in lower latency. Yet, local breakout has not been adopted by most operators, primarily because of trust issues in tracking the data used by a roaming subscriber, which currently is only done by the VO. This paper presents a trustworthy local breakout (LBO) solution that addresses the trust issue by having both the roaming user equipment and the VO keep record of data usage, thus leveraging their opposing incentives to keep both parties accurate. In addition, the solution streamlines the 5G registration process by enabling authentication and authorization directly with the VO, thus significantly speeding up the registration. The solution utilizes verifiable credentials to record the subscriber’s usage information and for the 5G registration. The analysis demonstrates that the registration process is streamlined, and usage information is now more trustworthy compared to the current LBO.