Abstract
A handover failure from a first communication service, such as voice over Wi-Fi, to a second communication service, such as voice over long-term evolution, may trigger a backoff timer on a user equipment (UE). This can delay the establishment of an IP multimedia subsystem (IMS) packet data network (PDN) connection and result in a temporary loss of voice service. This disclosure describes a method to address this issue. When the UE receives a PDN CONNECTIVITY REJECT message with one of a set of designated cause codes (e.g., "missing or unknown access point name") following a PDN connectivity request made for a handover, the UE can be configured to bypass a standard backoff timer procedure. Instead, the UE may initiate a new PDN connectivity procedure using a different request type, such as an "initial request." This action can facilitate the establishment of a new IMS PDN connection over the second communication service, helping to restore voice service functionality with less delay than might occur if the backoff timer were observed.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Mo, Max and Chuang, Poying, "Bypassing Connection Backoff Timers During Voice Over Wi-Fi to Voice Over Long Term Evolution Handover Failures", Technical Disclosure Commons, ()
https://www.tdcommons.org/dpubs_series/8827