Patent ID: 7003306

Claim:
Short message system for handling short messages (SMS-MO) sent by mobiles (MO), comprising switching arrangements (MSC) on which the mobiles (MO) depend for radio connection, and short message servers (SMSC) at which the messages from a mobile (SMS-MO) arrive and are routed back, in the form of messages “destined for a mobile” (SMS-MT), to the destination mobiles (MO′), the mobile sending messages (SMS-MO) including in the message the address of the server (SMSC) of a card (SIM), the system comprising: a virtual server (SMSC-V) which is defined by its address (ADR-V) and is associated with an operator, the address (ADR-V) of the virtual server (SMSC-V) being the only server address recorded on said cards (SIM); a real server (SMSC-R) which is defined by its address (ADR-R); the switching arrangement (MSC) contains an address translator for replacing the address (ADR-V) of the virtual server (SMSC-V) with the address (ADR-R) of the real server (SMSC-R) to which the message (SMS-MO) will be routed, which real server handles the message and routes it to the intended receiver (MO′); a prepaid card database (BD-CP RP) containing credit accounts of prepaid short message cards and their associated code numbers; and a prepaid short message card (CA), having a secret code (CD), which the subscriber purchases, the subscriber using a secret code (CD) and including the secret code (CD) in his short messages (SMS-MO), when there is no interactive vocal server (SVI) for top-up, whereby the real short message server (SMSC-R), upon receipt of a short message (SMS) from a mobile, verifies authorisation of transmission by checking the code (CD) and the account credit assigned to that code (CD) in the prepaid card database (BD-CPRP), and thereupon sends the message to the intended receiver (SMS-MT) if the credit permits, and, if no credit is permitted, the server (SMSC-R) sends a credit exhaustion message to the mobile (MO) which sent the message (SMS-MO).