The message waiting notification update system is operable in the serving
Mobile Switching Center and, upon receipt of a message-waiting
acknowledgement from the mobile subscriber station, updates the local
copy of the subscriber's data in the Visited Location Register and
forwards this information to the subscriber's Home Location Register. The
Home Location Register stores this received data for use when the next
successive Registration Notification is received from a new serving
Mobile Switching Center or in response to the subscriber initiating a
local access. When the serving Mobile Switching Center receives a
Registration Notification message return result from the subscriber's
Home Location Register and the message waiting notification count is the
same as the count previously sent to the Home Location Register, the
serving Mobile Switching Center does not have to transmit a message
waiting notification over the forward control channel to the mobile
subscriber station.