In a cellular telecommunications network, a method and system for performing
dormant
hand-off for a dormant Mobile Node (MN) between a source packet zone an a target
packet zone, when the MN still has an active A10 and Point-to Point Protocol
(PPP) connection in the target packet zone. According to the method, when handed-off,
the MN issues an origination request with a Data Ready to Sent (DRS) parameter
set to zero for the target Base Station Controller (BSC-T) which responsive to
the request further sends an A9-setup-A8 registration request to
a target Packet Control Function (PCF-T). The PCF-T then sends an A-11 Registration
Request message to a Packet Data Service Node (PDSN-T) of the target packet zone.
Responsive to the receipt of the Registration request, the PDSN-T sends an agent
advertisement message to the MN and initiates the Mobile IP (MIP) registration
procedure, and the MN can register the care-of-address information relating to
the new serving PDSN, the PDSN-T, with its Home Agent (HA). According to another
embodiment, the same method is to be used for performing a hand-off of the dormant
MN to the target packet zone, when the MN, before issuing the origination request,
demands the activation of a packet data session.