the security mode interaction process familiar and lets them practice service usage. Also when the user forgets/locks the PIN associated with generated key, it is simple to generate a new key and assign it a new sPIN destroying the previous versions using same process as with original registration, and most importantly: without need for replacement of the SIM card. In these systems there is commonly no secondary signing PIN unblocking code (sPUK) at all, because revelation of such a code has identical requirements for the requesting person's identity verification as was with original person's identity registration. Compare this with older "factory generated keys" model for older technology SIM cards that had insufficient processing power to do on-board key generation. The SIM card factory ran key-generation with special hardware accelerator and stored the key material on card along with initial sPIN and sPUK codes. Sometimes actual generation happened within the SIM card that was running in special manufacturing mode. After the generation the capability of doing it at all was usually disabled by blowing a special control fuse. Delivery of in particular the sPUK codes creates considerable security information logistics problems, which can entirely be avoided with the use of on-board key generation. Turkcell was the first provider to roll out a mobile signature service with "On Board Key Generation" functionality, which enables customers to create their signing and validation key pair, after they get the simcard. In this way GSM operators do not need to distribute signing PINs to customers. Customers can create their sPIN anew, on their own. In introduction of the Finnish Mobiilivarmenne service in 2010, only one out of three operators chose to use this on-board key generation capability with user interaction. Cited reasons claimed it to be too hard for the user. Actual experience did show that those without it created easily non-functional registrations without any online indication of the status, while usage of on-board key generation always resulted in positive indication of success when the service became fully functional for the user. Also if a mobile phone version had issues with SIM Application Toolkit protocol, that became evident immediately during a registration process using on-board key generation. Sources for the origins of the term mSign: Announcement of MSign formation (in German only), 17.10.2000 MoSign: Materna Monitor - company magazine, December 2004 MoSign: International Herald Tribune tech brief, 26 March 2001 MobilImza: Turkcell Mobil Imza 10.3.2008