SIP Trunking and the business IP-PBX: A brief overview
A PBX is an abbreviation of Private Branch Exchange, which is essentially a piece of hardware that is used to provide a business telephone system. A PBX will allow a business to deliver voice and video over an internal network, in addition to offering a variety of call management features. An IP (Internet Protocol) based PBX simply describes the mechanism for connection. Instead of connecting to the PSTN (Public Switched Telephone Network via ISDN (Integrated Services Digital Network), the connection is achieved via SIP.
Other than the ability to deliver calls more effectively around the business, the functionality that a PBX offers is one of the main reasons for a business to install one, or host one in the cloud. Some of these features, along with a summary as to what they do are provided below. Please note that the actual features available will vary depending on the model of the individual PBX.
Time of Day Routing
Time of Day Routing allows a business to control where their calls go during specific times / periods of the day. As a result, they can define in hours and out of office hours as well as bank holiday exceptions.
Allows the business using the PBX to record calls.
Voicemail to email
Voice to email allows a workforce to receive audio recordings of voicemail messages that are distributed to them via email.
Extension Groups allow a business to group together handsets / extensions so that when an inbound call comes into the business, all of the handsets / extensions will ring at the same time.
SIP is an abbreviation for Session Initiation Protocol, and SIP trunking is a VoIP (Voice over Internet Protocol) that is based on SIP. SIP trunking allows the delivery of telephone services as well as unified communications to any business equipped with an SIP based PBX via an ITSP (Internet Telephony Service Provider). The benefits of SIP trunking include:
- Effective utilisation of the available bandwidth by delivering voice and data in the same connection.
- Some providers offer free calls between different sites of the same business, or other businesses using the same ITSP as these calls are considered to be ‘on net’.
- Failover to ISND is still possible.
- No need to invest in additional PSTN gateways or additional line cards as you grow.
- Significantly reduced call delivery charges regardless of the country that you are routing calls to.