SIP trunks aren't just for PSTN access

This vendor-written tech primer has been edited by Network World to eliminate product promotion, but readers should note it will likely favor the submitter's approach.

IT managers often think of Session Initiation Protocol (SIP) trunks as a lower cost alternative to the T1/PRI trunks they use to access the PSTN. But SIP trunks provide flexible access to many more communications services than just the PSTN. These services can increase business agility, improve productivity and reduce costs.

Many stories have been written about enterprises that have slashed millions of dollars from their telecommunications bills by moving their PSTN services to SIP trunks. This Network World article, for example, discusses how Finish Line Sports saved $2 million over three years. But enterprises should also consider using SIP trunks to access cloud communications services and federate with business partners.

In fact, these services can be much quicker and easier to deploy while providing a high ROI. Tackling one of these projects before migrating the PSTN services gives the IT staff valuable experience and prepares them to migrate mission critical PSTN access services.

The Network World article notes the complexities of moving PSTN services from T1/PRI access lines to SIP trunks. These projects require close coordination with the enterprise's legacy network service provider to ensure the SIP trunk service provides equivalent functionality, including e911 services, compatibility with fax machines and other issues.

Cloud communications services

By definition, a SIP trunk is a virtual interface that connects enterprise communications systems with each other or to a third party communications service. They can be used to access audio or video conferencing, unified communications, contact center and other services, regardless of whether they are provided by on-premise equipment or hosted in the cloud. Cloud communications services are offered by a range of providers, from major carriers to specialty service providers.

Like any cloud application, all that is needed to access a hosted communication service is an IP network connection to the service provider and a SIP-capable communications system. The public Internet may provide a suitable connection, or a private peering relationship can be established over a carrier's MPLS network. Communications system makers have widely implemented SIP standards in their IP-PBX, contact center and UC product offerings.

By investing in SIP standards-based equipment, enterprises can take advantage of a wide array of communications services accessible over IP networks. They are no longer constrained by the one-to-one lock between access and service provider that typifies legacy TDM communications services. Enterprises can quickly and easily route communications traffic to specialist providers and optimize services based on cost, geographic reach, quality and other factors.

Cloud communications services not only increase the breadth of services available to enhance collaboration, they also provide an alternative to costly and time consuming premise-based communications system deployments. The pace of innovation has rapidly accelerated since shifting to SIP standards-based networks. Instead of investing in premise communications, many enterprises are purchasing cloud services.

Cloud communications services advantages:

  • Increase choice of services and providers
  • Reduce service provisioning time and increase business agility
  • Shift capital expenses to operating expenses
  • Reduce access costs by using IP networks, instead of TDM
  • Reduce service costs, because SIP-based communications services are frequently less expensive than TDM services

For example, a leading global technology company cut millions of dollars from its audio conferencing bill by establishing a SIP trunk peering connection between its data center and the conferencing provider.

Federation with Business Partners

SIP trunks can also connect enterprises with each other to create federated services. This enables customers and suppliers to share advanced unified communications functions presence, chat, audio/video communications and conferencing as if they were a single organization.

Federated communications can be delivered over private peering connections or using the Internet to connect organizations. Details vary by UC system, but generally each organization can control and apply policies to the communications allowed with federated partners. This ensures security and compliance.

Federation advantages are accelerate decision making and streamline supply chains and enhance collaboration with customers and partners.

Using SIP trunks and federation, enterprises can extend rich unified communications services to customers, creating stronger relationships and greater intimacy. SIP services can take advantage of high quality broadband IP networks to deliver high definition communications.

With a SIP-enabled enterprise, IT managers can quickly adapt to changing business conditions. They have flexibility to quickly add or change services. For example, an enterprise can:

" Use a cloud-based video conferencing service to setup conferencing with a major customer to support a new consulting project

" As the enterprise expands and establishes remote offices, it can add a hosted UC service that improves employee collaboration and accelerates decisions

" To streamline production with its major supplier, it can create a private peering relationship that enables federated UC services

SIP trunking technology provides a powerful tool IT managers can use to enhance business operations. It decouples communications services from transport networks and standardizes the access interface. By leveraging SIP trunks, enterprises can quickly and easily deliver rich collaboration experiences to a wide range of organizational stakeholders.

It is one of those game-changing technologies that IT teams need to factor into their long-term communications strategy.

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