Secure VoIP Call Analysis via CTI Key Correlation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing VoIP communication systems face challenges in real-time voice quality troubleshooting and call screening due to the encryption of media streams, where the SRTP key material is protected within call signaling, making it difficult to decrypt and analyze secure media packets.
Innovation Solution
A secure call analysis apparatus and method that establishes a secure connection between a call control agent and a call analysis device via a CTI interface, allowing the device to receive and correlate CTI events with secure media packets for decryption, enabling real-time voice quality troubleshooting and call screening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If media streams are encrypted for secure VoIP calls, then security and privacy are improved, but real-time voice quality troubleshooting and call screening become difficult
Solution Approach 1:
The patent introduces an intermediary component (call control agent or network element) that acts as a trusted mediator between the encrypted media streams and the analysis device. This intermediary has access to the encryption keys through secure channels and can selectively decrypt media packets for analysis while leaving the original encrypted communication intact, thus enabling analysis without compromising security
Solution Approach 2:
The system segments the media stream processing into two separate paths: the original encrypted media path for secure communication, and a separate analysis path where selected packets are decrypted and routed to the analysis device. This segmentation allows simultaneous secure communication and analysis without interfering with each other
2Reliability
If SRTP key material is protected within call signaling, then security is improved, but decryption and analysis of secure media packets become difficult
Solution Approach 1:
The call control agent serves as an intermediary that has authorized access to the protected SRTP key material within call signaling. It can extract and provide these keys to the analysis device through secure channels, enabling decryption without exposing the key protection mechanism to unauthorized access
Solution Approach 2:
The system enables the analysis device to autonomously obtain the necessary decryption keys and correlate them with media packets through automated key management processes. The device can independently perform decryption operations without manual intervention, making the process easier to operate while maintaining security
3Reliability
If call control messages are encrypted for secure communication, then security is improved, but real-time call analysis and troubleshooting become challenging
Solution Approach 1:
The call control agent acts as a trusted intermediary that can access encrypted call control messages, extract necessary information such as media keying material and call parameters, and provide this information to the analysis device in decrypted form, thus maintaining security while enabling analysis
Solution Approach 2:
The system creates copies of call control information and media packets at the call control agent, which then distributes these copies to the analysis device in appropriate formats. This copying mechanism allows the analysis device to receive necessary information without exposing the original encrypted communication channels
Data Source
AI summary
In one embodiment, a secure computer telephony integration (CTI) connection is established between a call analysis and/or screening device and a call control agent. The call analysis device sniffs secure media packets between the endpoints and receives CTI events from the call control agent via the secure CTI connection. The device correlates the CTI events with the secure media packets, enabling the device to decrypt the packets to perform voice quality troubleshooting or call screening in real-time.