Smart Phone and Next Generation Mobile Computing

124 Smart Phone and Next-Generation Mobile Computing

MSISDN number and determine the HLR of that number. The GMSC

then uses the MSISDN number to query the HLR, which returns the

current MSRN of the dialed number that identifies the current loca-

tion. Then, the GMSC is able to route the call to the current MSC

of the dialed number. Upon receiving notification of an incoming

call to a mobile station currently within its control, the MSC queries

its VLR for the TMSI of the mobile station by the MSRN number.

After that, a paging message is broadcast among all BSCs of the MSC.

The BSC that is serving the desired mobile station will reply to the

MSC. Finally, two parties of the call are indirectly located, and the

call can proceed. If the call is initiated ...