SIP trunking treats voice like data and sends the calls to a SIP provider that converts the calls to a traditional voice call to reach the called party on the PSTN. As the on-site phone system needs to talk to a SIP Provider’s Soft Switch there is an element of compatibility testing that needs to happen. Many SIP Providers are working with phone system manufacturers to pre-test their equipment.
A SIP service is where ISDN lines are consolidated into a single point meaning that customers need buy fewer lines. SaintGroup’ can offer a dedicated SIP Trunk for voice services only or a Multi-Service Access Connection which bundles a number of services down a single Ethernet access circuit such as SIP and Internet services.
SIP Trunking can provide additional resilience when multiple sites connect to the same SIP Provider and inter-site calls are free. A full range of dialling codes (021, 031, 011 etc) are available which means that a company could appear to be in 5 different geographic areas while only being in one. Issues faced when moving offices to another exchange are also overcome as the phones numbers are not physically allocated to an exchange as they are with ISDN and PSTN.
SIP Trunks have the advantage of allowing multiple services on one access thereby combining multiple budgets into one. They provide scalability by adding additional voice channels simply by a soft change, negating the need for a physical installation like ISDN30 and have the ability to divert calls free of charge to another site on SIP Trunk network in the case of Business Continuity. SIP trunking enables the ability to accept calls in a common place at the SIP Provider and then route them accordingly. SaintGroup is able to provide the ability for companies to move site and still retain an existing DDI range.