Soft Switch Extends PBX Features to Cellular Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Business professionals experience a loss of advanced phone features when outside the office, as current wireless communication systems do not effectively replicate the functionality of desktop phones, and simple call forwarding does not provide the desired features.
Innovation Solution
A communication system incorporating a soft switch that integrates with both cellular and wireless local area networks, using SIP signaling over a data-bearing path and PSTN signaling in IP format to provide PBX services, allowing for the replication of desktop phone features on cellular devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If simple call forwarding is used to re-route calls from desk phone to cell phone, then call routing capability is improved, but advanced phone features (call forwarding, voicemail, conference calling) are lost
Solution Approach 1:
The patent introduces a soft switch as an intermediary device that sits between the cellular network and the user's cell phone. This soft switch receives SIP signaling messages over the data-bearing path, translates them into PSTN-compatible signaling, and routes calls through the cellular voice-bearing path to the cell phone. The soft switch acts as a mediator that preserves advanced PBX features while enabling mobile connectivity, thus resolving the contradiction between simple call forwarding and feature retention.
Solution Approach 2:
The patent segments the communication system into distinct functional components: a soft switch handling signaling and feature processing, a cellular network providing voice and data paths, and a user device. By separating the signaling function (SIP over data path) from the voice transmission (PSTN over voice path), the system can deliver both call routing capability and advanced features simultaneously, resolving the technical contradiction.
2Adaptability or versatility
If SIP signaling is used over data-bearing path and PSTN signaling over voice-bearing path, then feature compatibility and seamless communication are improved, but system complexity increases
Solution Approach 1:
The soft switch serves as an intermediary that handles the complexity of dual signaling paths. It receives SIP signaling messages over the data-bearing path, processes them, and translates/converts them into appropriate PSTN signaling formats for the voice-bearing path. This intermediary approach enables feature compatibility across different networks while containing system complexity within a single manageable component.
Solution Approach 2:
The patent replaces traditional mechanical telephony systems with software-based signaling (SIP) over data networks. By substituting the legacy PSTN signaling mechanism with modern IP-based SIP signaling for feature control, while maintaining compatibility with traditional voice paths, the system achieves feature compatibility without requiring complete system replacement, thus managing complexity effectively.
Data Source
AI summary
A soft switch 134 providing wireless PBX voice services to a local area network (WLAN) is used to extend PBX functionality to the cellular domain. A dual mode remote unit is capable of receiving signals both in the cellular system as well as the WLAN. The cellular system is comprised of a data-bearing path and a voice-bearing path. When the dual mode remote unit is within the WLAN, it communicates both voice over IP (VoIP) signaling as well as session initiation protocol (SIP) control signaling over the WLAN. When the remote unit is outside the WLAN, it communicates voice signaling over the voice-bearing path of the cellular network using a standard cellular voice channel. In parallel, it uses the data-bearing path of the cellular network to transmit SIP control signaling.