SIP Trunking converges voice and data onto one pipe, providing seamless access between the Internet and the worldwide PSTN (Public-Switched Telephone Network), resulting in immediate cost saving. With SIP Trunking IP Network provides PSTN connectivity. A call travels the majority of its path over the IP network instead of on the PSTN and then drops back down to the destination/facility at the last mile. By implementing SIP Trunking as the carrier, traditional local and long distance charges decrease dramatically because the call travels mostly over the IP network and not on the PSTN.

For Example: An international call is placed to Cleveland, Ohio using an international dialing prefix and the local area phone number. The call travels the majority of the way over the IP network of the service provider and is then redirected back to the PSTN at the Cleveland (or closest city) POP (Point of Presence) at its termination point. Since the bulk of the call traveled over the IP Network at no incremental cost and not on the PSTN, the long distance rate is a mere fraction of what the traditional fee would be without the IP connection.

Although pricing for SIP Trunking is typically 40 - 70% below what legacy Telcos can offer, the features that enhance functionality, are the key considerations in the deployment of SIP Trunking. Below are some of the instant benefits of SIP Trunking.

Instant Cost Savings - Realize immediate cost saving by converging your local, long distance and broadband Internet services onto a single pipe with dynamic bandwidth allocation.

Economical Local and Long Distance - Reduce toll charges from SIP origination/termination services to the PSTN for local and long distance calls.

Relieve Hardware Costs - Reduce costs associated with purchase of new telephone equipment because of the monthly savings.

With SIP Trunking, choose DIDs from around the country and have them served to the central PBX, thus saving further on costs.

Disaster Recovery - Enable faster, more efficient disaster recovery with an IP network's distributed architecture, inherently more fault tolerant than fixed line, circuit-switched counterparts.

Flexibility - Allow selection of a single SIP Trunk, increasing the flexibility and ease of adding, subtracting or changing a line.

SIP Trunking is the latest technology, but has been proven for years in large market telephone systems. In almost every case the payoff for new equipment is less than 3 years. This is based entirely on the savings realized vs. traditional telephone lines.

For business's wanting to make full use of their installed IP-PBXs and not only communicate over IP within the business, but also outside the business a SIP trunk provided by an Internet Telephony Service Provider to connect to the traditional PSTN network is the solution. Unlike in traditional telephony, where bundles of physical wires were once delivered from the service provider to a business, a SIP trunk allows a company to replace these traditional fixed PSTN lines with PSTN connectivity via a SIP trunking service provider on the Internet.

SIP trunks can offer significant cost-savings for enterprises, eliminating the need for local PSTN gateways, costly ISDN BRIs (Basic Rate Interfaces) or PRIs (Primary Rate Interfaces).

There are three components necessary to successfully deploy SIP trunks: a PBX with a SIP-enabled trunk side, an enterprise edge device understanding SIP and an Internet telephony or SIP trunking service provider.

In most cases the PBX is an IP-based PBX, communicating with all endpoints over IP, but it may just as well be a traditional digital or analog PBX. The sole requirement is that an interface for SIP trunking connectivity is available.

The PBX on the LAN connects to the ITSP via the enterprise border element.The enterprise edge component can either be a firewall with complete support for SIP or an edge device connected to the firewall, handling the traversal of the SIP traffic.

On the Internet, the ITSP (Internet Telephone Service Provider) provides connectivity to the PSTN (Public Switched Telephone Network) for communication with mobile and fixed phones.