SIPREC for Real-Time Text
The device can record real-time text (RTT) in SBC sessions. RTT is carried in RTP and allows text to be sent immediately as it's created through wireless handsets that use IP-based technology on networks that support RTT.
For recording audio with RTT calls (i.e., two media streams), additional SBC media channel resources are required. For example, recording 100 SBC sessions of which 30 contain RTT, the following licenses are required: "SIPREC Streams" = 100, "SBC Sessions" = 100, and "SBC Media" = 60 (30 for the RTT sessions + 30 for the RTT sessions sent to SRS).