What is SIP Trunking?

Modern telecoms is based on Internet Protocol (IP) and to run Voice over IP (VoIP) you need SIP trunks.

Traditional telephone systems use connections to the UK network (‘lines’) based on either ISDN (digital) or analogue technology. These are dedicated physical lines which are expensive and cannot support the latest technology.  In the world of VoIP these are replaced by IP pathways between your phone system and the T4Com  SIP platforms in our London datacentre: the calls are carried over an internet based service.  These IP pathways are known as SIP Trunks (one SIP Trunk supports one voice call). SIP refers to the technology used for VoIP call setup and control.

SIP Trunks can utilize part of an existing data circuit (for instance you may have a private circuit internet connection) or alternatively  we can install a suitable  VoIP optimised circuit (see VoIP circuits). These are lower cost and you only pay for the capacity you need. Lower cost and no wastage.

SIP Trunking, how does it work?

In our London datacentre the T4Com SIP Platforms interconnect with the UK and international phone networks via multiple access points. As your Internet Telephony Service Provider we handle all your calls (both inbound and outbound) passing them to your system over SIP Trunks. The SIP Trunks are IP and are carried over the internet.

Benefits of T4Com SIP Trunks

• Excellent audio quality as standard (using the same codec as ISDN) but we also support HD Voice and Video for advanced applications.
• Up to 40% lower cost than BT ISDN30e  (Rental and Connection). Circuits combining voice and data will save even more.
• Perfect for T4Com Ethernet circuits.
• Keep your old phone numbers (We’ll port them for you) or have new numbers from multiple UK dial codes regardless of your location.
• Proven interoperability with 3CX, Asterisk, Avaya, Cisco, Mitel, Sangoma, Beronet and others.
• Multiple DR and resilience options.

We run our own infrastructure and carrier interconnects developed with deep industry experience: we don’t re-brand or white label someone else’s product.

Our monitoring systems are not only used on our core infrastructure: they are also focussed on each SIP customer’s service.

For resilience all T4Com SIP Trunks come with  access to two independent T4Com SIP Platforms (main and standby) as standard.