From chartreuse cover plates, 'Yankee Doodle' ring-tones, and speed-dial settings for our favorite out-of-town pizza joint, users strive to personalize the generic cell-phone. U.S. wireless users are typically forced to start the customization process from scratch every time they get a new phone. The new Subscriber Identity Module (SIM) cards mean that now users can literally plug a new identity into their phones.

SIM 'smart cards' have until now only been available for Europe and Asia's GSM (Global System for Mobile Communications) standards-based phones. Now they are coming to North America by way of Nextel's iDEN network and Motorola's i85 Java-based phone.

About the size of a postage stamp, the SIM cards make subscriber information portable and independent of the phone. They have been in use for quite a long time outside of North America. The microprocessor-controlled plastic cards store frequently-dialed phone numbers, language settings, voice mail info, and user authentication data. This creates "plastic roaming" -- the ability to move from country to country regardless of the handset in use at the moment.

Gemplus is a SIM card-maker for the GSM market. The company announced plans earlier this month to supply SIM cards for Motorola's new i85 phones. The phones will work both on Nextel's voice and data iDEN network and the European GSM network. Other than GSM and satellite phones, iDEN is the only other network currently supporting phones using SIM cards.

"This is a groundbreaking development for North American wireless networks," said Jean-Louis Carrara, Director of Telecommunications for Gemplus in North America. "The use of SIM cards in the Nextel network is a tremendous endorsement of smart card technologies."

SIM cards were adopted in 1990 by the GSM standard as a response to growing illegal 'cloning' of cell phones. SIM cards dramatically cut the amount of fraud by separating subscriber information from the phone. The new security required phone users to identify themselves as the handset owner by entering a PIN number each time the phone was turned on.

Along with the added security, SIM cards allow networks to create tailored menus and services. Only 24 million of the smart cards were purchased in North America in 2001. That number should rise to 124 million by 2004, with Gartner Group predicting 80% of mobile devices using smart cards by that year.

SIM cards protect the security of the handset. In addition, WAP Identity Module (WIM) smart cards use encryption to establish a secure environment for mobile e-commerce using WAP-enabled wireless phones. WIM is part of the WAP 1.2 specification. Already, several companies, including smart-card giants Gemplus and Schlumberger have announced support for WIM.

Both Gemplus and Schlumberger are part of the SIM Alliance formed last year promoting global standards for smart cards and SIM cards. The companies have released products for upcoming 3G networks and a new generation of smart phones.

Conclusion

How important will smart cards be to our mobile future? Here's a little anecdote that may illuminate this issue: A French businessman was about to be arrested last year for his involvement in a corruption scandal. He thought the information on his card was so potentially damaging that he ate his cell-phone's SIM card as police closed in.

Although that is an extreme reaction, analysts say smart cards will play an increasingly important part in our mobile lives. Introducing smart cards opens a wide array of possibilities. As more phones are purchased over-the-counter at 7-11s and discount retailers, a way to identify the anonymous user for mobile transactions will be needed. As information stored in the handset becomes more important than the device itself, SIMs will be vital.

Ed Sutherland is a New York-based editor and journalist