Dynamic Media Routing Across IP and PSTN Networks
Solution Overview
Problem
In converged communications networks, especially in single-server systems, there is a need for effective management of IP bandwidth usage and provision of alternate communication paths during high traffic periods or network resource unavailability, as existing techniques like PSTN Fallback and Separation of Bearer and Signaling are inadequate for managing IP bandwidth and providing alternate paths efficiently.
Innovation Solution
The dynamic establishment of inter-gateway connections through public or private networks, where the bearer path is selected based on bandwidth and resource availability, using a common electronic address and identifier to establish a circuit-switched bearer channel over a separate network when the primary network is incapable of supporting the communication session, allowing for flexible and efficient management of voice communications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple communication gateways are controlled by a single controller with private switching facilities, then voice communications can be established across geographically distributed enterprises, but the system becomes vulnerable to network failures and bandwidth exhaustion when IP network resources are insufficient or components go down
Solution Approach 1:
The system dynamically selects between IP network and PSTN based on real-time network conditions, bandwidth availability, and resource status. The call controller continuously monitors IP network health and automatically switches routing paths without manual intervention, making the system adaptable to changing network conditions while maintaining reliable voice communication
Solution Approach 2:
The public switched telephone network (PSTN) serves as an intermediary backup path when the primary IP network fails or becomes unavailable. The system uses PSTN facilities as a mediator to maintain voice communication when IP network resources are exhausted, thus improving reliability without requiring permanent dual-path infrastructure
2Reliability
If manual intervention is required for users to recognize problems and dial DID numbers for alternate routing, then public network trunks can be utilized for bypassing failures, but user effort and call setup time increase significantly
Solution Approach 1:
The call controller automatically detects network failures and initiates alternate routing through PSTN without requiring user action. The system monitors IP network conditions, determines when alternate paths are needed, and executes the routing switch autonomously, thereby maintaining reliability while eliminating manual user intervention
Solution Approach 2:
The system continuously monitors IP network bandwidth availability, component status, and call quality metrics. When feedback indicates network degradation or failure, the call controller automatically triggers alternate routing through PSTN. This closed-loop feedback mechanism ensures reliable communication while simplifying operation by removing manual detection and routing decisions
3Reliability
If independent media servers are used in each enterprise with separate call controller functionality, then system autonomy and fault isolation are improved, but inter-enterprise call management and bandwidth control become more complex
Solution Approach 1:
The call controller is designed with multi-functionality to handle both intra-enterprise and inter-enterprise calls through a unified interface. It manages IP network routing, PSTN fallback, bandwidth control, and media server coordination across multiple enterprises through standardized protocols, thereby maintaining fault isolation while simplifying inter-enterprise call management
4Loss of energy
If IP trunks are used for voice communications over WAN, then bandwidth utilization and cost efficiency are improved, but call quality deteriorates when network delay and packet loss reach threshold levels
Solution Approach 1:
The call controller continuously monitors IP network quality metrics including delay and packet loss. When feedback indicates quality degradation beyond acceptable thresholds, the system automatically switches to PSTN for voice bearer traffic while maintaining IP network usage for signaling, thus preserving call quality while continuing to utilize IP bandwidth efficiently for control functions
Solution Approach 2:
The system dynamically adjusts the routing of voice bearer traffic based on real-time IP network conditions. During periods of good network quality, voice traffic flows over IP to maximize bandwidth efficiency. When quality deteriorates, the system dynamically transitions to PSTN for voice while maintaining IP for signaling, thereby optimizing both bandwidth utilization and call quality according to current network state
Data Source
AI summary
In one configuration, an enterprise network is provided that includes geographically dislocated first and second network regions 202 and 206, the first and second network regions being in communication with one another through first and second networks 252 and 248 and respectively comprising first and second gateways 220 and 224 and first and second groupings of links connected to the second network 248. A common electronic address is associated with the second grouping of links. In response to a request from a first subscriber to initiate a communication session with a second subscriber in the other network region, a media server 200 determines that the first network 252 is currently incapable of supporting the bearer channel for the session. In response, the first gateway 220 transmits the common electronic address to the second gateway 224. After the common electronic address is received by the second gateway 224, the first gateway 220 transmits in band to the second gateway 224 an identifier that is used to establish the communication session.