SIP Auto-Answer for VoIP Feature Implementation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The first-party design of Session Initiation Protocol (SIP) and other VoIP protocols makes it difficult to implement advanced features like Push to Talk, Information Tone, Click to Call, and Remote Monitoring, as these features require user intervention and are not inherently supported in the current SIP standard.
Innovation Solution
Implementing an auto-answer feature in SIP by configuring receiving devices to automatically acknowledge and answer calls from trusted third parties, using the trusted third party's identity carried in the protocol's message header, allowing for the implementation of advanced features without extending the SIP standard.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If SIP follows a first-party design where the party executing SIP commands is one of the parties involved in communication, then the protocol architecture remains simple and widely adopted, but advanced features like Push to Talk, Information Tone, Click to Call, and Remote Monitoring become difficult to implement
Solution Approach 1:
The patent introduces a trusted third party server as an intermediary that mediates between the initiating device and the receiving device. The third party server sends the INVITE request on behalf of the initiating device, allowing the receiving device to automatically answer calls from trusted parties without requiring complex protocol extensions. This intermediary approach enables advanced features while maintaining simple first-party SIP architecture.
2Ease of manufacture
If the receiving device automatically answers calls from trusted third parties by skipping to OK response, then implementation of Push to Talk, Information Tone, Click to Call, and Remote Monitoring becomes easy, but the device must trust and authenticate third party identities carried in message headers
Solution Approach 1:
The receiving device implements a feedback mechanism by examining the From header in INVITE requests and comparing it against a pre-configured list of trusted third party identities. This authentication feedback loop ensures that only calls from verified trusted parties trigger auto-answer behavior, maintaining security while enabling easy implementation of advanced features.
3Extent of automation
If the receiving device skips to OK response for authenticated third party calls, then call establishment time is reduced and automation is enhanced, but user intervention is eliminated which may reduce awareness of incoming calls
Solution Approach 1:
The auto-answer feature is applied selectively based on local quality criteria - specifically, the identity of the calling party. The receiving device maintains different response behaviors for different sources: automatic OK response for authenticated trusted third parties, while potentially maintaining ringing or other notifications for other callers. This localized application of auto-answer preserves user awareness for important calls while enabling automation for trusted communications.
Data Source
AI summary
An auto-answer feature is implemented in SIP by configuring a receiving device to automatically acknowledge and answer an incoming call or session from a specific trusted third party. The receiving device may skip to an OK response to an INVITE request when the call is routed through the trusted third party. When the device can automatically answer the incoming call, advanced features such as Push To Talk, Information Tone, Click to Call, and Remote Monitoring may be easily implemented.