This Recommendation is part of the Gateway Control Protocol family of Recommendations and extends the basic functionality in [ITU-T H.248.1]. This Recommendation describes a new SDP attribute that allows for the carriage of properties in the local and remote descriptor in the textual ITU-T H.248 encoding.

The advantages of this approach are:

– if ITU-T H.248 properties for Local and Remote Descriptor usage are available (due to existing ITU-T H.248 packages from e.g., the ITU-T H.248.x-series of Recommendations), but a correspondent SDP information element is missing, then new SDP attributes do not have to be defined and registered for each property;

– that the property is defined in one place and is applicable to both binary and textual encodings.