Home System in C#

Recognizer QR in C# Home System

origination [digits=feature code string] 1 2 SMSREQ [MS identity, request address of serving MSC] smsreq [address of serving MSC] 5 proprietary information transfer 3 4 call setup to CSC and dialogue with customer

Figure 155 Registration activation on call origination for an MS requiring reprogramming (1) The potential subscriber makes a call to the wireless service provider The subscriber enters a feature code and presses SEND (2) Since the MS is already programmed and active, the call is established between the subscriber and a

responds back to the OTAF using the smsreq message This message acts as an acknowledgment and specifies the address of the serving MSC to be used for reprogramming the MS

Deferred registration activation for a preprogrammed MS is used when an existing subscriber calls the CSC from a wire-line or other phone, not the MS to be programmed This scenario is similar to the registration activation on call origination for a preprogrammed MS, except that the call is

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made to the CSC before the MS is powered on Since this is a reprogramming procedure, a subscriber profile exists within the HLR The CSC informs the OTAF that this is a reprogramming procedure and the OTAF uses the short-message service SMSRequest message to query the HLR for the address of the OTASP SME At some later time when the MS is powered on, normal registration will occur and the network will be aware of the location of the MS to be programmed (see Figure 156) In some cases, the MS requires reprogramming, but the preprogrammed parameters within the NAM are unknown to the network In this case, registration of the MS will fail, and OTASP can continue as if the MS were unprogrammed

After the serving MSC is attached to the OTAF using call origination or registration procedures, the A-key for subscriber authentication must be generated This procedure is quite different from the typical method for entering an A-key into the mobile station (see 11) Typically the entire 26-digit A-key is entered manually via the MS keypad, preprogrammed internally by the MS manufacturer, or programmed through the data port of the MS equipment Since OTASP must be a secure process, it makes no sense to send the full A-key as an over-the-air parameter to be programmed into the MS This could lead to fraudulent access of the A-key and enable cloning fraud Therefore, a new procedure has been developed to generate the 26-digit (ie, 64-bit) A-key within the MS based on the Diffie-Hellman Key Agreement Standard procedure

The Diffie-Hellman Key Agreement Standard procedure is a cryptography algorithm that supports the distribution of temporary keys to generate identical authentication keys (A-keys) on both the mobile station and the authentication center (AC) The Diffie-Hellman procedure is patented in the United States and Canada under patents #4,200,770 and #4,218,582 The patent expired on April 29, 1997 and is available for public use by any party, with no obligation to pay royalties Patent # 5,930,362 is in effect for applying the Diffie-Hellman Key Agreement Standard to A-key generation in wireless networks

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Part 2:

proprietary SMSREQ [MS identity, information transfer request address of serving MSC] 3 smsreq [access denied] 4 power-on registration 5 6 REGNOT regnot 7 SMSNOT [address of serving MSC] smsnot