Use your cellphone as a boarding pass

First came the kiosk, a strange addition to airport terminals when Continental Airlines began offering it as a check-in option in 1995. It was followed by Web check-in, introduced by Alaska Airlines in 1999.

Now Continental is testing electronic passes, allowing travelers to pass through security and to board planes without handling paper. Their boarding pass is an image of an encrypted bar code displayed on their phone’s screen, which can be scanned by gate agents and security personnel.

When using the other airlines’ mobile check-in services, customers still have to print a boarding pass at an airport kiosk, though most carriers are eager to eliminate this step once the Transportation Security Administration gives its approval.

The agency has been working with Continental since December to test electronic boarding passes, which for now can be used only for nonstop domestic flights out of the Houston hub of Continental.

The technology being tested by Continental uses a two-dimensional encrypted bar code, which is much tougher to copy than the one-dimensional bar code used by many airlines for boarding passes printed online. And that is a major reason the T.S.A. is expected to embrace the technology.

With the electronic boarding passes, passengers still need to show photo identification when they pass through security, and that ID must match the information in the bar code on the phone.

The one-dimensional bar code is the symbol most familiar to consumers — a series of vertical lines. The two-dimensional version looks more like the snow on a television screen that has lost its signal. It can hold more information and is more adaptable than the magnetic stripes that used to be the industry standard.

Not only are those magnetic stripes more expensive to print; they also do not work with the Web and the mobile check-in options that carriers hope more passengers will embrace.

The International Air Transport Association, which establishes global guidelines for the airline industry, announced a standard for two-dimensional bar codes last October, and expects that its 240 members will be using these bar codes exclusively by the end of 2010. That will save the industry about $500 million annually, and will also pave the way for wider adoption of electronic boarding passes, which several foreign carriers have already introduced.

Air Canada, for instance, has been using electronic boarding passes with its mobile check-in service since last September, for flights to domestic and international destinations except those in the United States. Other foreign carriers that use some type of digital boarding pass system include Japan Airlines, Scandinavian Airlines and Spanair.

As mobile devices become more sophisticated and applications for smaller screens evolve, airlines expect passengers will be able to use their phones, BlackBerrys and other mobile devices for a growing number of services, like rebooking a ticket after a missed connection, switching seats, checking standby status or seeking an upgrade. (info & photo from The New York Times)