KeyBank prides itself on knowing its customers' needs. Now that familiarity extends to its computers as well.

Since August, KeyBank has required customers who do their banking online to register their personal computers, in addition to their user IDs and passwords. The measure is intended to protect client accounts from unauthorized use.

"Security is of utmost importance," said Paul Graning, senior vice president of virtual distribution channels for KeyBank. "But the application has to be usable."

KeyBank customers answer a few questions when they sign up for online banking that creates a thumbprint of their computer. That information is tied to the client's user name and password; when a customer signs on, all three have to match for access to his or her account.

The measure was developed by KeyBank technology specialists to comply with a new federal mandate that requires financial institutions to add an extra layer of authentication for online transactions.

The Federal Financial Institution's Examination Council issued a Dec. 31 deadline for compliance to guidelines it issued in 2001. The extra security measures are intended to protect customer information, prevent money laundering and terrorist financing, reduce fraud and inhibit identity theft.

"We live in a world of heightened security," said Lloyd LaFountain, superintendent of the Maine Bureau of Financial Institutions. "(These measures) potentially prohibit others from accessing your account."

Bank of America has a set-up similar to KeyBank's where a customer selects a personal icon that affirms the user's identity and the bank's Web site. Other banks have also adopted new security measures, such as requiring clients to provide their ATM personal identification numbers.

Christopher Pinkham, president of the Maine Association of Community Banks, said some local banks have issued matrix cards with unique series of letters and numbers that customers log on with. The variation of security measures among financial institutions is an added plus for protecting consumers and outsmarting hackers.

"It makes it more difficult for the bad guys," he said.

Individual banks also decide which transactions require the extra protection and which don't.

"The general rule of thumb is if an account number or a Social Security number is in play, you have to have the higher authentication," he said.

Customers have caught on fairly well. Pinkham said Kennebec Savings Bank was one of the first to roll out its new online security measures, which it did this summer in waves to get customers accustomed to the new process. Graning, of KeyBank, said they've had relatively few problems with the new system, to the point where they don't need to extend the contracts of the temporary staff hired to help with the transition.

"We thought we perfected a usability solution, and then we tweaked it," he said, noting that about half of the bank's customer base uses online banking - about 800,000 people. "The biggest thing is educating the client, so we like to tell them 'Come in for a test drive.'"