Handover Based IMS Registration Scheme for Next Generation Mobile Networks

Pseudocode 2

Authentication at S-CSCF.

SCSCF receives request

IF method == ”HANDOVER”

IF RES == XRES & integrity-protected == true then

IPaddress = Contact;

P-CSCF_IPaddress = Path;

IF P-CSCFold != P-CSCFnew then

Route “HANDOVER” to P-CSCFnew

ENDIF

ELSEIF method == “REGISTER”

IF RES != XRES then

Create User-challenge( );

route(Service-Routes);

reply( 401 , Unauthorized - Challenging UE );

ELSEIF RES == XRES then

Set -status == 200

Route “OK” to ICSCF

ENDIF

ENDIF

ENDIF