The first SIM card was made in 1991 by Munich smart card maker Giesecke & Devrient, who sold the first 300 SIM cards to Finnish wireless network operator Radiolinja.
The specification that standardized the micro-SIM form factor continues to evolve. Some features introduced recently include:
§ A micro-SIM form factor
§ Allowance for multiple simultaneous applications accessing the card through logical channels
§ Mutual authentication as a way to eliminate carrier spoofing by allowing the SIM card to authenticate the cell tower to which it is connecting
§ PIN protection with hierarchical PIN management with a universal PIN, an application PIN and a local PIN.
