ReayLink is a "walkie-talkie" service, which utilizes Session Initiation Protocol (SIP), offered by the Sprint Nextel Corporation. It is necessary to have a Sanyo or a Samsung ReadyLink capable phone and a matching service-plan in order to use this feature. ReadyLink seeks to mimic the forerunning "MOTO Talk"/Nextel walkie-talkie service, except that ReadyLink was created for the CDMA-based phones under the Sprint PCS side of the corporation.