IMS (IP Multimedia Subsystem) has an architectural framework designed to deliver IP multimedia and voice services to both wireless and wireline devices. Unfortunately, the concept was ahead of its time and the original design was difficult to implement.
But the subsequent application of new technology has simplified operation and enabled massive scaling. Now IMS is enabling voice calls to be made over 4G/LTE networks, and it's also being seen as an alternative way to deliver cloud-centric UC services to enterprises.
The original intention was to enable the delivery of IP multimedia services over cellular wireless networks; then, at a later date, the design was changed to bring in wireline networks, e.g., the PSTN. That decision facilitated fixed-mobile convergence, but it also upped the cost and complexity.
In addition IMS was initially designed to allow different value-added services to share common components such as billing, but the timing was unfortunate: The Net bubble burst and the services didn't get to see the light of day.
Although IMS enables voice to be delivered over 4G/LTE, the more elaborate communications scenarios envisaged for IMS didn't materialize, expensive systems were not widely deployed, and the world moved on. Right now communications applications are fragmented across different services, devices and networks, and enterprises are struggling to keep up with a complex mix of communications technologies as well as the increasing demands of mobile workforces.
So given the history, why would we expect the original IMS vision, and the same or similar functionality, to be relevant to an enterprise's UC requirements? And what difference would it make?
A New Communications Bar
These words came from ABI Research and they rekindled my interest in IMS.
"Enterprises are struggling to keep up with the change in communication technology. With many devices available to communicate, the management of communications on multiple platforms has become increasingly challenging. Keeping this in mind, organizations still need to stay up to date with the latest communications technology, as a lack of enhanced communications services available in the workplace may result in the company falling behind its competitors. IMS is an alternative to unified communications (UC) in the enterprise."
Analysts are not always right, and I don't agree with the wording of the last sentence, but it is clear that the communications bar has risen in recent years, and users now expect to get whatever they need, whenever and wherever they are at that moment. Therefore UC has to be ubiquitous, and in turn that means enabling a full set of services--IM, video calling and conferencing, web conferencing and desktop sharing--across different mobile devices having different operating systems.
Desktop sharing was emphasized because it is equally clear that wireline (LAN) systems and devices have to be brought into the equation. Therefore UC solutions should provide a consistent user experience across all devices and over both local area and wide area wireless networks. That is where IMS can play a pivotal role.
One of IMS's early design objectives was the delivery of IP multimedia services over both cellular and wireline networks. That was its original raison d'être. Therefore it can be used to create a unified, seamless UC environment, which is what the market says it wants.
For example, Alcatel-Lucent talks about a "new conversation experience", one that connects all the end-user's contacts and communications in the online and real worlds, and organizes that experience via a single, intuitive interface available on any screen, regardless of the network.
Virtualized IMS
IMS used to come in a big cabinet full of 19-inch rack hardware, but the relentless growth of technology has given us Network Functions Virtualization (NFV). This is an SDN technology that relies upon, but differs from, regular server virtualization as employed in enterprise IT.
NFV decouples network functions from dedicated hardware appliances, thereby enabling them to perform the requisite functionality in software on commodity servers. This is the development that enables IMS functionality to be virtualized; and the logical place to deploy virtualized IMS is in the cloud, where it takes its place alongside other virtualized computing and communications assets.
The transition from purpose-built native hardware to virtualized IT hardware and cloud deployments changes the cost structure. Cloud deployment methods reduce both capital and operating expenditure, which will lead to lower prices and increased deployments. Software pricing will also benefit, but will scale differently in the enterprise market than in the telecom markets where IMS is used to enable voice calls to be made over LTE networks.
A Complex Landscape
Right now we conduct real-time conversations on different devices that use different networks and they overlap with various asynchronous messaging services. The whole communications process is fragmented, and time is wasted managing and prioritizing messages.
The complexity in today's communications landscape comes from service silos that create individual functionality islands. In order to enable the new conversation experience, we need to bring everything together in ways that complement and enhance our business and personal lifestyles.
A small handful of vendors are marketing solutions that they claim can deliver that experience. In addition to Alcatel-Lucent and Ericsson, BroadSoft's UC-One IMS is particularly interesting. Michael Tessler, CEO and President of Broadsoft, said:
"There is an undeniable enterprise shift currently underway from premise-based communications services to cloud-enabled mobile UC. UC-One IMS extends the benefits of the cloud by enabling enterprises to manage a single communications service subscription for their employees, in turn driving down their telecommunications costs and management complexity."
By enabling easy movement between services, devices and the individuals who are communicating and collaborating, UC can eliminate communications boundaries. Users can, for example, start an instant message chat and move to a voice conversation, or initiate a call from a laptop interface and move to a smartphone without losing connectivity, and a single conversation can turn into a conference call.
IMS-centric UC enables better roaming from an enterprise's fixed access network to carrier-provided mobile access. The technology provides home network control even for subscribers on visited (mobile) networks. In addition, IMS is an open standard, and that makes it easier to introduce third-party applications into the enterprise's IMS session control layer. And doing it in cloud makes everything cost-effective.
Open Innovation
However, in order to embed and extend the new capabilities, the creativity and vertical focus of third-party developers is needed. By securely exposing communications assets, service providers can add value and create new business models. The following figure illustrates how Alcatel-Lucent provides this facility.
High-level APIs hide technology details and enable easy development of IMS applications. Schematic courtesy Alcatel-Lucent.
This figure also indicates how UC is evolving and becoming a valuable collaboration tool for business-to-business and business-to consumer communications. It is also being integrated with business processes and is evolving into an application enablement platform that developers can use to create smart applications having embedded UC.
Conclusions
Technology promises to make our lives easier, but all too often it doesn't deliver on the promise. We shouldn't need to think about the communications process: instead it should be simple, pleasurable and effective.
The transition to virtualized IMS hardware running in the cloud is the big UC game changer. IMS is also the catalyst that will enable mobile network operators to deliver advanced services such as presence, IM, video and data sharing to a single access point: the mobile phone number.
