What does a VoIP Gateway Do?
Basics of the VoIP Gateway
Depending on the needs and existing infrastructure, businesses often require different kinds of hardware and software to get their VoIP system off the ground. A VoIP gateway is a common device found in most networks and it is important for managers to know what a gateway is and what it does.
VoIP gateways are generally stand-alone devices performing the very basic function of converting VoIP calls to analog signals (to transmit over the PSTN) or vice versa. It can also be used to connect a traditional PBX to the IP system. This allows businesses to use land lines in some situations and VoIP for others such as routing only interoffice calls over data networks. The simple and relatively inexpensive gateways generally use the G.711 codec for data compression which requires more bandwidth. There are also many powerful devices which use the G.729 codec for achieving better compression with lower data consumption.
Types of Gateways
1. Analog: These can be either FXS or FXO gateways. An FXS can connect legacy desk phones and fax machines to a VoIP system. On the other hand, the FXO gateway allows an office to connect the VoIP phone system to their PSTN lines.
2. Digital: These can be used to connect VoIP phone systems to digital voice lines namely T1 in the US and E1 or BRI in Europe.
In general, VoIP gateways are compliant with multiple protocols such as SIP, H.323 etc. They are also compatible with many different codecs ranging from G.711 to G.729a. Before purchasing a gateway, you might want to check if it includes support for the T.38 protocol which is necessary if you want the ability to send faxes. Many devices also include built-in support for echo cancellation and jitter buffers for managing call quality.
Which One is Right for You?
There is usually a web based administrative console which can be used to manage the device and configure it. If the VoIP gateway supports automatic provisioning, it is much easier to provision IP phones throughout the organization. Some older models may lack advanced call routing features but most new hardware has at least call routing capabilities. An important point to keep in mind when purchasing VoIP gateways is to know how many devices or phone lines your office needs to connect, since different models have varying connecting ports. Your business VoIP pricing will vary depending on this.
The type or particular model of device you purchase will depend on the features you need and the price you can afford. Needless to say, prudent managers will invest in quality hardware which will last longer and offer better controls.