VoIP Gateways Article

While most technologically literate people are aware that voice over IP (VoIP) technology involves encoding voice into data and transmitting it as a digital signal, there are important differences in the ways this can happen, and companies shopping for enterprise VoIP should be aware of these differences. For starters, it’s critical to differentiate between VoIP gateways and an IP PBX (News - Alert).

VoIP gateway. A VoIP gateway (or PSTN Gateway) is a device which converts telephony traffic into IP for transmission over a data network. It allows you to convert between a legacy telephony connection and a modern VoIP connection using Session Initiation Protocol (News - Alert), or SIP. It’s sometimes referred to as a “digital gateway” because the voice media is converted between a digital TDM connection and a VoIP connection. A VoIP gateway can connect a modern VoIP-only system, such as a virtualized IP PBX, to a PSTN PRI trunk.

IP-PBX. An IP PBX is a private branch exchange (telephone switching system within an enterprise) that switches calls between VoIP users on local lines while allowing all users to share a certain number of external phone lines. The IP PBX maintains a directory of all phones and users in an organization and their corresponding SIP address, making it easy to connect internal calls or route external through the VoIP service provider. A lot of the difference between an IP PBX and VoIP gateway is where the digital transformation of voice takes place; in an IP PBX system, the conversion of the voice packets into data packets happens at the source.

So which solution is right for your company? That will depend on a number of factors, according to Chris Lee (News - Alert) blogging for EZTalks. An IP PBX may involve a cost-prohibitive amount of cabling.

“A VolP gateway is arguably the most optimal solution for a network that wants to adopt the voice over internet protocol,” he wrote. “The biggest pro for a company using a VoIP gateway versus an IP-PBX is that the company can either have an easy upgrade path to VolP or even have multiplicity of devices and use the gateway as a kind of translator.”

An IP PBX, on the other hand, can have advantages for certain organizations. It can, for example, translate data packets for the POTS (plain old telephone service) infrastructure whenever needed for things like analog faxes.

Before you make the transformation to VoIP, it’s important to understand your current telephony situation, your infrastructure, your IT resources, your needs and your budget before you begin shopping for a new solution.