Taking a non-mathematical approach, this text covers the GSM digital wireless standard. It is aimed at engineers, telecommunications managers and technicians.... such as credit card calling or prepaid wireless services. personal unblocking key (PUK) - (1 - GSM) A key code that is used to ... The PIN can accidentally become invalid if the user attempts to enter an incorrect PIN number 3 times in a row.
|Author||:||Lawrence Harte, Richard Levine, Geoff Livingston|
|Publisher||:||McGraw Hill Professional - 1999|