Signing the dotted line, digitally
- By Michelle Speir
- Feb 09, 2003
Although pen and paper have not quite gone the way of the dinosaurs, their use is declining in the federal government, especially now that electronic signatures are considered legally binding.
Public-key infrastructure (PKI) and digital certificates are examples of ways to electronically authenticate or "sign" documents. These methods are highly secure but can be complicated to implement and use.
One alternative is electronic signature capture. This method uses a person's physical signature instead of an electronic marker to authenticate documents. An electronic signature capture pad is used to capture the signature and place a graphic representation of it within the digital framework of the document.
If you've recently used a credit card at a retail store, you're probably familiar with this type of pad. It houses an LCD screen that lights up, showing a line upon which you sign your name with a stylus.
The ePad-ink from Interlink Electronics Inc. goes one step further than simply recognizing the signature itself. It also captures biometric information about the signature such as the speed and pressure of the stylus. What's more, the pad can be used in conjunction with other biometric devices, such as a fingerprint capturing device or smart card, to help establish identity.
The ePad also features two-directional communication, which can turn the pad into an interactive touch screen terminal for survey responses and personal identification numbers.
You can buy the ePad-ink by itself for use in a developer environment or you can select one of three bundled solutions that include signature verification software from Silanis Technology Inc., Communications Intelligence Corp. (CIC) or Valyd Inc.
The ePad-ink features a 3.8-inch monochrome LCD screen with a backlight and 320 x 240 resolution. Images were clear and easy to see.
Because the pad is a USB device, it does not require an external power source. (A serial version is available for the same price as the USB version, but you'll need to use a separate power supply that comes bundled with it.)
We tested the pad with Valyd's eSign software, an application that integrates with Microsoft Corp. Word 97/2000/XP, Excel 97/2000/XP, Outlook 2000, Outlook Express Auto CAD and Adobe Systems Inc. Acrobat v4.0/5.0.
The eSign software facilitates signature capture, content hashing and signature and document verification. Content hashing binds the graphic representation of the signature to the document so that any alteration will render the signature invalid. The signature also cannot be copied and pasted into another document.
With signature and document verification, the signature on the document can be verified to check the authenticity of the signer and the integrity of the document.
Enrolling a signature follows a similar process to that used when enrolling biometric identifiers. The system requires five similar signature captures along with a form containing the signer's name, user ID, password and other information.
Upon enrollment you can also create an eSign stamp that allows you to import your signature into a document without physically signing on the pad. Similarly, a briefcase feature allows you to sign, import and verify documents on desktops where you have not enrolled.
When you sign a document, eSign requires you to enter information about your location and reason for signing. This information is saved along with the signature. You also can choose to freeze the entire document or sections of it after signing, which completely disables all editing functions to ensure the document cannot be altered in any way. If the document is not frozen and a change is made an "X" appears through the signature, marking it invalid.
eSign blends seamlessly into the applications with which it integrates. In Microsoft Word and Outlook, for example, two buttons appear on a new toolbar offering options for signing the document in real time with the pad and importing a signature.
Signature verification seems set at a reasonable threshold, which is good because the software doesn't offer a threshold adjustment. Manual threshold adjustments can be convenient for some systems, but they can also compromise security if set too low.
When signing, we had to make sure we signed at the same pace and with the same lettering as we did during enrollment. A few times the system did not accept our first attempt at signing but accepted the second one, when we signed more carefully.
Of course, importing your signature enables you to skip the physical signing process, which is convenient if you have many documents to sign.
Agencies looking for a simple, affordable, user-friendly way to electronically sign and verify documents should consider the ePad-ink. It offers a nice level of flexibility because customers can choose one of three bundled software options or choose to develop a custom application.