SIP trunking, originally seen as a way of reducing outbound telephone call costs, now has a new network access consolidation dimension that is relevant to large, distributed businesses, either single or multi-country.
SIP trunks, (with session border control and session management) can help organizations support an increasing number of secure, low-cost, reliable communications channels with high connection quality. The central architecture can also facilitate the deployment of collaboration services and applications.
Market drivers include:
- Gartner has shown that SIP trunks can cost at least 28% less than Primary Rate Interface (PRI) trunks with comparable throughput. The aggregation of SIP trunks in the enterprise yields further cost improvements due to lower PSTN charges, as well as economies of scale. Gartner estimates savings on voice and data connectivity ranging from 30% to 50% for branch environments in midsize and large enterprises.
- The porting of numbers to SIP addresses in a next-generation network enables the consolidation of a large number of local-office ISDN or analog connections to be centralized into common access connections. Network planners can save on local PSTN access, decommission the associated local access gateways and consolidate the total number of external connections required for the voice network. The benefit of using SIP trunking for the distributed branch network is that the calling line identity of the user can be retained, thus maintaining the local area number, while leveraging the WAN to transport calls to and from the local office.
- Session border controllers (SBCs) can reduce SIP-based denial of service (DoS) threats that originate from within and outside an organization, and provide interoperability with various versions of SIP being used by service providers and enterprises.
- Session management provides dial plan normalization, interconnection with disparate platforms and endpoints, call admission control, toll cost optimization, and collaboration application deployment and policy management.
- The complementary functions of session management and session border control improve enterprise communications security, collaboration application deployment, operational efficiency, and reliability.
