ITU-T H.248.3 PDF

This Recommendation defines a package that extends the applicability of the ITU-T H.248.1 Gateway control protocol. Specifically, the packages in Recommendation ITU-T H.248.3 define a framework for specifying capabilities associated with user interface elements, such as text display, keys, dynamically labelled keys, indicators and alphanumeric input. In addition, specific extension packages for telephone keypads and telephone function keys are defined.