This Recommendation defines a dynamic tone definition package for use with the H.248.1 Gateway Control Protocol. The dynamic tone definition package allows flexible tone specification in a media gateway for feedback to audio receivers. A tone can be defined by assigning properties (for example, frequency or duration) to an existing tone (i.e., a tone defined in some other package) or a new tone. As defined in ITU-T Rec. H.248.1, a "package" is an extension to H.248.1 that supports specific behavior.

NOTE This Recommendation has been renumbered. It was formerly known as ITU-T H.248 Annex J.