Service blending for converged IMS services — a BT Alcatel-Lucent collaboration

Abstract

BT has embarked on an ambitious and innovative programme to replace its current core network with an all-IP next generation network (NGN) known as 21CN. One of the important properties of an NGN is to allow new and innovative services to be created and deployed quickly, easily and cost effectively. However, managing the sheer number of services, be they generated in-house or by a third party, that will be hosted on such an NGN is not a trivial task. The process of service orchestration (i.e. service blending) is complex and the major standards bodies have, as yet, been unable to define a suitable method. One of the contenders for the role of service orchestration is the Alcatel-Lucent Service Broker TM . BT has been engaged with Alcatel-Lucent during the past year on a proof of concept demonstration to test the Alcatel-Lucent Service Broker's suitability for this role. The findings have shown that this development can support and aid rapid service creation and blending while providing excellent levels of flexibility and programmability. IntroductionBT is already well on the way to converting its existing core network infrastructure to a next generation network (NGN) based on the Internet protocol (IP) and known as the 21st Century Network (21CN). NGNs such as 21CN offer communications operators a number of benefits, not least a reduction in operating costs [1], and a platform that allows new and innovative services to be developed and launched quickly and in a cost-effective way. In the past, new services have largely required independent platforms, each having common features such as billing and customer profile maintenance, often using different protocols. The result is a complex arrangement of networks and platforms involving a myriad of stove-pipe solutions. In contrast, NGNs such as 21CN, offer a common platform that can be used by all applications and services. Commonly used features can be aggregated into common capabilities (CC) [2], and currently there are 12 CCs in the 21CN architecture that can be reused across applications.The common platform allows new services to reuse previously developed functionality, reducing time to market and development costs. It is also possible to look beyond the 'walled garden' architecture that has been the norm and allow third parties to develop and provide services to customers.An important part of the BT NGN architecture is the IP multimedia subsystem (IMS) [3], defined originally as the core network for 3rd generation (3G) mobile systems by the 3rd Generation Partnership Project (3GPP). The IMS was first introduced in the Release 5 (R5) of the 3GPP set of standards. Later releases of the 3GPP standard included interfaces with wireless LAN systems (in R6) and fixed line systems (in R7), paving the way for fixed-mobile convergence (FMC) and providing for new levels of convergence and mobility. A typical scenario might, for example, allow a user to have a single profile for both fixed and mobile services, combining multiple devices. As such, the IMS will herald a new era...

Cellular mobile — the generation game

“…The essential concepts of the project were taken up by various standards bodies and 3GPP, in particular, have Fig 12 BRAIN all-IP converged architecture (often called a 'system beyond 3G'). [20] and Roxburgh et al [21]). As we have seen, the current 3G R99 network offers data users only a bit-pipe service with 50-100 kbit/s of throughput and 100-200 ms delay -there is currently no support or standard way of offering services that Internet users take for granted, such as e-mail, instant messaging, voice over IP or Web Services.…”

“…The IMS (see Fig 14 and Abhayawardhana et al [20]) is the industry response to these issues, providing a platform for advanced IP services -like VoIP and IM -as well as a standard method of interworking to the PSTN and WLAN networks. The IMS is, in essence, a carrier-grade SIP (session initiation protocol [23]) server.…”

SIP mediated services

“…The LSB is programmable via steplets which are Java code that it can dynamically load to instruct the service broker core on how to handle SIP messages. The LSB was a convenient platform to use since it was already undergoing trials at BT for potential integration into the 21CN platform [2,16]. In Fig 7, multimedia audio and video streams are carried using the RTP [17].…”

“…BT's 21CN is based on the IP multimedia sub-system (IMS) standard architecture, which in turn is based on SIP [1,2]. Since the goal of the IMS is to provide ubiquitous access to all existing and future Internet services, adopting SIP as the control protocol for IMS brings immediate access to some of today's most popular and fastest growing Internet services.…”