Tom Van Pelt, Technical Director, GSMA
With end-to-end encryption now rolling out, Rich Communication Services (RCS) is continuing to mature as a richer, more consistent messaging experience across networks and devices. Building on the progress introduced in RCS Universal Profile 3.1 and the more visible advances delivered through RCS Universal Profile 4.0, I am pleased to announce the publication of the RCS Universal Profile 4.1 specifications.
Refined end-to-end encryption interoperability
Unlike some recent releases, Universal Profile 4.1 is not focused on introducing major new consumer-facing features. Instead, it strengthens the foundations of the RCS ecosystem, ensuring services work more securely, efficiently and consistently across different networks, devices and messaging platforms.
A key enhancement is the refinement of the end-to-end encryption (E2EE) specifications. These updates incorporate lessons learned from extensive interoperability testing to ensure that when two users exchange encrypted RCS messages using different messaging clients or services, the encryption works seamlessly regardless of who provides the underlying technology.
By incorporating these findings into the standard, Universal Profile 4.1 helps ensure a more consistent, interoperable and secure experience across the broader RCS ecosystem while maintaining strong user privacy.
gRPC-based connectionless transport for messaging and signalling
Universal Profile 4.1 also updates the underlying transport mechanisms used to exchange messages and signalling between networks. Specifically, it introduces an optimised, connectionless transport protocol based on gRPC1, a widely used framework designed for efficient, high-performance communications between systems.
In simple terms, this is less about building new roads and more about changing how traffic moves across the existing ones. Instead of relying on larger, less efficient vehicles, the updated approach is closer to using smaller cars able to carry information more efficiently, reducing overhead and helping messages travel with less unnecessary resource use. By making the transport layer more efficient and resilient, RCS services can operate with greater stability, reliability and scalability
These improvements help support core RCS capabilities, including person-to-person messaging, business messaging, Messaging Initiated Video Calls (MIVC), and spam and scam reporting. They also provide a stronger foundation for future innovation as RCS adoption continues to grow globally.
For consumers, these changes will largely go unnoticed, and that is precisely the goal. Whether sending an encrypted message to a friend on another network, participating in a group chat, or interacting with a business via RCS, users should be able to trust that the service will work securely, reliably and consistently. Universal Profile 4.1 delivers important behind-the-scenes improvements that help make that possible.
Granular privacy controls for profile sharing
That said, there is one noticeable new feature for users: easier profile sharing. This feature allows users to share their name and image from existing profiles such as their Google, Apple or operator accounts in a conversation, ensuring that parties in a conversation become easier to identify, particularly in group settings. In keeping with RCS’s focus on ensuring their privacy, users will be able to control who can receive that information.
As more people and businesses around the world start using RCS, this update helps ensure it works consistently across different phones, mobile networks and countries. It is all part of the GSMA’s commitment to open collaboration and interoperability, helping the mobile industry continue its move beyond SMS towards richer, safer and more dependable messaging for everyone.
Please get in touch if you have any questions or you would like to know more about RCS messaging.