Design, Implementation and Validation of an Open Source IP-PBX/VoIP Gateway Multi-Core SoC

The telephony world is consistently moving to the transmission of voice through packet networks, so as to unify data and voice and to enable the provisioning of new services in a less costly manner. Service providers are offloading the task of converting analog voice to VoIP to the end-points. In this paper we present an IP-PBX/VoIP Gateway system based on a single, multi-core SoC that performs all the required processing. The system targets the low density market of home gateways and SME IP-PBXs, where cost is the main factor. We prove it is feasible to implement a 4-channel IP-PBX/VoIP gateway on a SoC based purely on both software and hardware provided by the open-source community, reducing both upfront and final product costs thus allowing new players into the market. The highly configurable design allows the integration of multiple embedded cores in the same die increasing channel density while reducing clock cycles per channel. The idea of using one or more open-source embedded cores can be extended to many different applications requiring moderate DSP performance, resulting in a “DSP-free”, low-cost system, with minimal design effort.