If you are a business using a SIP trunking solution or virtually any business involved in multiple communication platforms a Universal Media Gateway has become a necessary evil for you to maintain. Others unfamiliar with this technology will appreciate this article’s description of its use and necessity. UMG defined It is essentially a translation and transcoder device to translate between all the different and disparate communication protocols including PSTN, SS7, Next Generation Networks and PBX. This device enables the ability to communicate over multiple communication protocols. Although it might make sense to have a standardized communication protocol, as technology develops, several protocols can be in use at any one time for various levels of communication. Imagine the different protocols in place for phone calls over tradition telephone lines compared with mobile conversations related through cellular towers or those over VoIP technology. UMG Transfer Protocols Current UMGs tend use Session Initiation Protocol (SIP) especially when trunking and are stand alone units. However other protocols such as Media Gateway Control Protocol (MGCP) or Megaco protocols are also used in UMG units. VoIP media gateways generally perform conversion between Time-division Multiplexing (MTD) voice calls to a media streaming protocol such as Real-Time Transport Protocol (RTP). There are also protocols for radio signal transfer from radio access on public networks to a Next Generation Core Network. Communication Protocols These various protocols need to be able to communicate with each other and a universal media gateway accomplishes that. These protocols include: – PSTN, Public switched telephone network – which includes the global circuit switched telephony networks which includes tradition transmission lines, fibre optic lines, cell networks, satellite phone networks, and the large undersea telephone cables. Original PSTN’s were government run or controlled but privatization has seen most of them sold. – SS7, Signalling System No. 7 – is the actual set up and tear down protocol for actual telephone calls, short message services (sms), number portability and prepaid billing mechanisms. Most PSTN’s use the SS7 protocol. – Next Generation Network, NGN’s – are networks that combine packet protocols for transferring data over IP networks, such as the internet. NGNs involve three separate major architectural changes depending on the supporting infrastructure; the core of this change is taking voice communications from the traditional PSTN to a voice over internet protocol application. – PBX, private branch exchange – are generally private telephone exchanges for private business or offices as opposed to those used for the general public. Calling within the building extensions is enabled by a PBX. Although these are the most popular protocols there are others in use and a new universal media gateway should be able to handle as many as possible for best value.