SRVCC for Emergency Callbacks via IMS Anchoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Single Radio Voice Call Continuity (SRVCC) technologies do not support emergency callbacks or click-to-dial sessions, as the Session Initiation Protocol (SIP) lacks protocol extensions for emergency callbacks, and existing SRVCC functionality does not provide special treatment for emergency situations.
Innovation Solution
The implementation of apparatuses and methods that include processors and memory configured to function as various components of the Internet Protocol Multimedia Subsystem (IMS), such as the Serving Call Session Control Function (S-CSCF), Emergency Access Transfer Function (EATF), and Access Transfer Control Function (ATCF), to enable SRVCC functionality for emergency callbacks and click-to-dial sessions by anchoring emergency communication sessions and communicating with other IMS components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the SIP protocol is used for emergency calls, then emergency call functionality is provided, but the protocol lacks extensions to support emergency callbacks and special treatment
Solution Approach 1:
The patent applies universality by enabling the existing SIP protocol to handle multiple emergency call scenarios (initial emergency calls, emergency callbacks, and click-to-dial sessions) through a unified mechanism. The system uses the existing SIP INVITE message and P-Asserted-Identity header to provide special treatment for emergency callbacks without requiring separate protocol extensions, allowing one protocol to serve multiple emergency communication needs.
2Adaptability or versatility
If SRVCC functionality is implemented for regular calls, then voice call continuity is achieved, but emergency callbacks and click-to-dial sessions are not supported
Solution Approach 1:
The patent applies local quality by implementing SRVCC functionality specifically for emergency callback and click-to-dial sessions while maintaining existing SRVCC capabilities for regular calls. The system identifies emergency sessions through the P-Asserted-Identity header and applies special handling only to these emergency cases, allowing different treatment for different call types without affecting the overall SRVCC reliability for regular voice calls.
3Reliability
If IMS networking technology is deployed, then service quality is improved, but coverage is not universal and legacy networks must be used for compatibility
Solution Approach 1:
The patent applies universality by enabling the IMS network to handle both emergency callbacks and regular voice calls through a unified SRVCC mechanism. The system uses the P-Asserted-Identity header to identify emergency sessions and applies appropriate handling regardless of whether the user is roaming or in the home network, providing universal emergency service support across different network configurations and locations.
Data Source
AI summary
An example apparatus is caused to receive a message inviting a user equipment (UE) to participate in an emergency communication session with an originating node, where the user equipment is registered with an Internet Protocol Multimedia Subsystem (IMS). The apparatus is caused to identify a type of registration of the UE with the IMS, and select a transfer function of the IMS to anchor the emergency communication session based on the identified type of registration of the user equipment with the IMS. The transfer function may be a domain transfer function or emergency access transfer function of the IMS. The apparatus is also caused to prepare the message for transmission to the selected transfer function to thereby enable the selected transfer function to anchor the emergency communication session and further communicate with one or more other components of the IMS to establish the emergency communication session with the user equipment.