Rich Communication Services (RCS) is a communication protocol standard between mobile telephone carriers, based on IP Multimedia Subsystem, developed and defined by the GSM Association (GSMA). It aims to be a replacement of SMS and MMS, with a richer text-message system. This has been adopted by Android manufacturers for native messaging, and Apple has recently announced that they will also support this protocol.

By adopting RCS as the default off-net messaging protocol, Avaya would differentiate their offering from other vendors. This would also provide clients with the ability to see read receipts and other advanced features as they interact with their customers.