Onestream GFX is a VoIP gateway that can be connected to an analogue telephone system and provide automatic routing of calls between the PBX and a VoIP service or pass calls through to the PSTN Telephone lines. The Onestream GFX also has built in GSM modules that use a standard mobile phone SIM card so that calls can also be routed directly over the GSM mobile phone network.

The Telecom FM Onestream GFX is a VoIP Gateway that can be connected in-line between the analogue line ports of a telephone system and the PSTN telephone lines. The OnestreamGFX has the added advantage of also including a 2 channel GSM Gateway and intelligent routing. This means that the Onestream GFX can be connected to a standard analogue telephone system and can look at all the calls coming from the PBX and route the calls via VoIP or GSM or pass through the call to the PSTN telephone lines. Inbound calls from VoIP and GSM can also be routed to the PBX. This combination of features makes the Onestream GFX a powerful tool providing a low cost solution for legacy PBX's to take advantage of low cost VoIP and GSM services without the need to replace the whole telephone system.