This Recommendation is one of a series of Recommendations to enable support for preferential telecommunication services over IPCablecom networks. These specifications do not apply toordinary emergency calls such as people calling the police, the fire department, ambulances, etc.Aspects of preferential telecommunications include provisions for authentication and priority(special handling). The objective of this Recommendation is to provide an initial set of priority specifications for preferential telecommunications within IPCablecom2 networks according to the framework described in [ITU-T J.261]. This Recommendation defines two options for introducing the priority header during signalling. This Recommendation defines specifications for capabilities which, when implemented, should help support preferential telecommunication services.NOTE – Pre-emption specifications and authorization specifications are outside the scope of this Recommendation and are considered to be national matters.