Voice over data-packet protocol, for example voice over Internet Protocol (VoIP), type communications in a network providing wireless packet data service are optimized by implementation of a mobile station initiated negotiation of radio protocol parameters adapted specifically to support the voice over data-packet application. Call set-up signaling for such a call utilizes a set of parameters for radio communication defined for a normal packet data service, for example, with packet retransmission between the base station and the mobile station. The mobile station recognizes the VoIP communication. When VoIP call set-up signaling over the robust link is complete, the mobile station sends a request to the radio network to modify one or more of the radio parameters, for example, to turn-OFF the packet retransmission; to facilitate the actual communication of VoIP packets.