Feature

SIP A Work In Progress

SIP A Work In Progress

Kenny Presly

Because it is one of the fundamental building blocks of a modern IP network SIP will influence the thinking of telecoms services and applications developers. In turn, Telco's, mobile operators, service providers, ISPs, equipment vendors, and software houses will use SIP. And the spread of SIP throughout telecommunications generally will make SIP a key protocol within the enterprise network.

In principle, SIP offers many advantages and benefits including:

•  Aiding service providers in the development of new services quickly and cost-effectively, and in a more open equipment environment than for traditional networks. This in itself will make SIP an attractive proposition to end users over those which are currently available

Who will use SIP?

•  Simplification of programming through the use of text-style control messages within an open standard. Further, troubleshooting will be less complex through the use of this open standards format. SIP follows many of the principles made familiar by other Internet protocols and applications (for example, HTTP and DNS), thus easing learning and training.

•  Independence from the underlying transport network and protocols, and support for mobility.

•  Support for multi-device feature levelling and negotiation, so that two dissimilar end devices can negotiate a reduced service that both can support – for example, a videophone can establish a voice call with an audio-only phone. Basically the devices will look for a common feature to communicate

•  A lightweight protocol that is scaleable and suited for a highly distributed and versatile network environment.

 

SIP Today

Already, large numbers of companies within the telecom industry are utilising SIP. Telco's, carriers, and service providers are offering SIP-based services such as local and long distance telephony with reduced tariffs, presence and instant messaging, IP Centrex, voice messaging, push-to-talk, and multimedia conferencing. All 3G mobile networks will use SIP.

There can be no doubt that SIP is changing the way customers select their networking infrastructure. Open standards means more choice and competitive pricing. SIP offers the customer opportunities to structure their business in a cost efficient manner. Convergence means a single network infrastructure. Home workers equate to reduced overheads. Presence means enhanced corporate visibility. Users can select a free softphone download from a website and within minutes they can be a remote extension of an office hundreds of miles away. Combine that with the ability to collaborate with their co-workers across the Internet and it is easy to see why the office of the future will be established in multiple locations with no loss of functionality or efficiency.

While QoS (Quality of Service) and security remain key factors in determining the take up of IP Networks as a medium for voice, players in the telecoms industry are positioning themselves for the change. The applications that are currently being offered will be enhanced by even more innovative solutions to business issues. The drivers will be reduced cost without reduction in functionality. The use of SIP has been fundamental in the deployment of Hosted PBX. SIP has enabled vendors to achieve interoperability in a much faster timeframe than previously allowed in the communications industry.

 

SIP Tomorrow

Telecoms resellers will need to embrace SIP as an enabler of value added services in much the same way as traditional voice resellers proposed legacy features and applications to a PBX sale. Voice as a data packet is fast becoming the norm. VoIP gateways offer an immediate solution to those not wishing to make wholesale changes to their infrastructure.

There are still some interesting challenges ahead and its fair to say that as individuals we will probably use only a fraction of the services that SIP will provide. In the past choices were based around analogue or digital services from an incumbent Telco to provide voice. Anything that strayed from that path was looked upon as having a limited future because it did not offer the uniformity and interoperability which end users required to make a simple call. SIP is about to redraw the map.

 

www.mayflex.co.uk