Until recently, WebRTC and RCS concepts have been little more than food for fights between technologists within the telecommunications community. However, in today’s context of Triple Play business-to-consumer convergence, new projects are undertaken to enhance (and also to marry) these concepts.
The goal is to provide operators with new possibilities to deliver innovative and advanced collaborative services. These services would be likely to provide new ways to value investments in data-intensive networks such as IMS (IP Multimedia Subsystem) and LTE (Long Term Evolution).
What are the stakes all about?
RCS (Rich Communication Suite) is one of the initiatives being led by European Network Operators (Orange, Vodafone, Telefonica, Deutsche Telekom, Telecom Italia), as well as Network and Peripheral Providers that will exploit the IMS infrastructure based on SIP, in order to provide advanced communication and collaboration.
The idea behind this project is to provide users with an experience beyond that of a voice and short message service (SMS), by providing instant messaging, live video sharing and file transfer over any device and any network with anyone in their mobile address book who has the capacity to handle rich data. It is, however, a project that is still in its infancy, although the challenge of the existing studies is to contribute to the standardization of this service in the long term.
On the other side of these innovative services offered by operators and the GSMA on mobile networks and upcoming services on the Internet, the Web community began to offer the integration of voice and video communications within Web services. Over the past decade, we have witnessed a significant evolution of the Web. The pages have gone from static information to full-fledged applications with excellent interactivity and functionality.
Video-conferencing has also been affected by this trend. Multimedia communication applications have begun to appear in Web browsers enabled by proprietary plug-ins such as Adobe Flash. Although these products, in many cases, provided a full video-conference and collaborative experiences, they often relied on proprietary solutions and protocols imposed by the browser plug-in developer instead of well-known standards.
In this context, the WebRTC concept is defined and developed to offer real-time peer-to-peer communications to the Web by taking advantage of HTML5 and existing real-time protocols and codecs instead of defining new ones. WebRTC, touted as “Web 3.0”, is a joint effort of the World Wide Web Consortium (W3C) WebRTC Working Group and the WebRTC Group of the Internet Engineering Task Force (IETF).
From now on, the first implementations of WebRTC are still under development. However, the definition is still not complete and it is likely to still undergo significant changes before being commercially viable. Thus, any experimentation on this technology is encouraged by the consortium, largely in order to obtain feedback.
Technical protocols continue to open up the implementation of these services as described in standardization committees (IETF, GSMA, 3GPP). In the state of the art, the Rich Communication Suite (RCS) standard is defined by the Global System Mobile Alliance (GSMA) standardization committee.
In late 2016, global operators, GSMA and Google announced the launch of a mobile industry initiative to accelerate the availability of Rich Communications Services (RCS). The protocols already fueled several initial first experiments, however these are still not widely available, and they do not allow operators to become sufficiently mature to deliver these multimedia services and to interconnect very heterogeneous solutions / systems. In particular, implementations highlight that many technical issues are not correctly or fully implemented at the moment, raising several challenges which need to be addressed early on for a successful deployment.
First, the binding to the SIM card. Indeed, since the RCS services are linked to the SIM card, cases such as roaming are serious challenges that cannot be solved. In particular, these use cases aim to replace Cloud-based ‘Over The Top’ (OTT) applications (such as WhatsApp), whose access is not limited by the SIM card.
In addition, in the case where the user uses multiple SIM cards depending on the availability of the network and the tariff requirements, experiments remain to be done to propose processes managing the heterogeneity of the RCS data. In addition, there is the issue of interoperability between operator networks. Given the large-scale deployment of IMS, interoperability between the different SCR clients of the terminal provider and the interworking of SCR services between operators are the main objectives of the SCR initiative.
Although a common set of GSMA processes is followed by RCS, a longer launch cycle time is required in practice because of the multiple verifications to be performed by the operator to validate interoperability between different vendor solutions. This delay is also partly related to the availability of open APIs.
In the RCS standard, there is nothing to oppose a use in the Internet area, but the major players of the field (Google & Firefox) seem to have adopted the WebRTC standard for multimedia services. The SIP protocol is then likely to be the basis for interconnecting the two technologies WebRTC and RCS.
For now, WebRTC / RCS interoperability is not proven yet, both technologies are still very recent and service providers rarely communicate publically about potential deployments in their network. The interest of WebRTC inter-browser communication technology to ensure the continuity of service of the RCS standard was raised at the 17th International Conference on Intelligence in Next Generation Networks.
Among other things, the fact that WebRTC is designed for mobile devices at the base and has its own API is a technical challenge for operators. The ultimate challenge is to ensure that end-to-end multimedia services work between a fixed terminal (web browser) and a mobile terminal.
Hervé, Consultant, Leyton France
 Rich Communications Services – the next generation of operator messaging – GSMA
 17th International Conference on Intelligence in Next Generation Networks (ICIN) Some WebRTC opportunities for RCS: And some inner challenges to overcome – 2013