Proxy DTMF Signal Generation for IP Telephony
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
IP telephone terminals often lack the capability to send DTMF tone signals, making it difficult and costly to ensure that DTMF tone signals associated with button presses are transmitted to opposite parties, especially in scenarios involving multiple IP telephone terminals connected to a local area network.
Innovation Solution
A DTMF tone signal transmission method and system that utilizes a proxy to transmit DTMF tone signals by replacing or adding them to RTP packets, allowing IP telephone terminals without DTMF capabilities to request and relay these signals through a local area network and the internet to the receiving terminal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If every IP telephone terminal is equipped with DTMF tone signal sending capability, then the reliability of DTMF transmission is improved, but the device complexity and cost increase
Solution Approach 1:
The patent introduces a proxy server as an intermediary component that handles DTMF tone signal generation and transmission. Instead of requiring each IP telephone terminal to have built-in DTMF capability, the proxy server acts as a mediator that receives requests from IP terminals and generates the appropriate DTMF tones, thereby reducing terminal complexity while maintaining transmission reliability
Solution Approach 2:
The DTMF tone generation function is extracted from the IP telephone terminal and relocated to the proxy server. This separation allows the terminal to remain simple while the complex DTMF generation capability resides in the shared proxy infrastructure, resolving the contradiction between reliability and device complexity
2Adaptability or versatility
If DTMF tone signal transmission is implemented in all IP telephone terminals, then the adaptability of the system is improved, but the manufacturing cost increases
Solution Approach 1:
The proxy server provides universal DTMF transmission capability that serves multiple IP telephone terminals simultaneously. Instead of manufacturing each terminal with expensive built-in DTMF capability, a single multi-functional proxy server provides the service to all terminals, reducing manufacturing costs while maintaining system adaptability
Solution Approach 2:
The DTMF transmission capability is implemented as a shared service that can be copied or replicated across multiple proxy servers if needed, rather than requiring expensive hardware DTMF generators in each terminal. This software-based approach reduces manufacturing costs while maintaining versatility
Data Source
AI summary
It is made possible for a DTMF tone signal associated with a button depressed on an IP telephone terminal to arrive at the opposite party even if an IP telephone terminal does not have a function of sending a DTMF tone signal. If a DTMF tone signal transmission request signal detection unit in a proxy detects a DTMF tone signal transmission request signal inserted in an RTP packet or a SIP packet received from an IP telephone terminal or detects a DTMF digit signal contained in the DTMF tone signal transmission request signal, a DTMF tone signal generation unit generates a DTMF tone signal associated with the DTMF digit signal. A voice encoder encodes the DTMF tone signal in the same way as a voice signal. An RTP payload replacement unit replaces a voice signal in a payload of the RTP packet with the encoded DTMF tone signal.