GUEST COLUMN: Biometric Signature Authentication for the Information Age

By Dr. Tatiana Vazioulina, Parascript, LLC

The dramatic rise of financial fraud has become a scary trend in today's world. According to recent studies, approximately 9.2 million Americans suffered from identity theft crimes in 2004, costing consumers $5 billion, and banks and corporations $48 billion. The growth of these crimes has resulted in a renewed interest in advanced security means. Institutions are increasingly demanding more reliable, less costly authentication and authorization for everyday activities, such as performing financial transactions, boarding an aircraft, entering a secure physical location or crossing international borders. Biometrics is an emerging technology that is quickly garnering wide attention for its promises to alleviate security breaches and offer solutions to key challenges, such as financial theft and fraud, faced by real-world enterprises.Biometrics is used to verify identity by way of physiological traits or behavioral characteristics that are unique to each individual and cannot be forgotten, lost or stolen. It can take the form of several different techniques such as hand geometry, iris or retinal scans, dynamic signature verification, face and voice recognition, fingerprinting and others.

Among these methods is biometric handwriting. Signature characteristics are absolutely unique to an individual and virtually impossible to duplicate. Therefore, handwriting still remains one of the most powerful human identifiers today. In dynamic signature verification, multiple biometric characteristics of a signature in question are scrutinized and compared against a reference signature kept on file to make a conclusion that measures the confidence of the signature's genuineness. If several genuine reference signatures are available, the measure of the stability of the particular feature is developed and used to estimate the probability of deviations observed in the questionable signature.

The most advanced signature verification systems employ a powerful combination of engines using different approaches for comprehensive signature verification. Each engine analyzes biometric characteristics such as speed, acceleration, deceleration, stroke sequencing and length, pen pressure and timing information received directly during the act of signing together with other innovative technology that scrutinizes signature shape. Finally, the results received from different methods of analysis are combined to provide a reliable measure of the likelihood of coincidence between the signature in question and genuine reference signature(s). The success of dynamic signature verification in such systems relies on analysis of graphical representation of a signature and biometric characteristics received during the process of signing. Usage of several independent methods of analysis leads to a dramatic performance improvement and adds substantial robustness to the signature verification software.

Since there are many different characteristics involved in the analysis, the biometric signature verification technology is able to ensure a high efficiency of verification even if certain characteristics of signing (i.e. pressure) are not tracked. This important aspect of signature authentication reduces dependence on the type, specifics and quality of pen-enabled or pointing devices. For example, pressure characteristics are very important if the signature is obtained on pressure sensitive devices and less important if captured on pointing devices built into many laptop computers that are not sensitive to exerted pressure.

Technological advancements have increased the accuracy of biometrics systems while making them more widely affordable as a viable method of verification. Due to the level of reliability, convenience and high security that biometrics provides, it is already being used extensively in a number of applications to provide a competitive edge to alternative technologies.

At the same time, not all biometric methods are equally acceptable in all industries and all applications. One of the greatest challenges of biometrics are privacy concerns due to its relatively intrusive nature. It is for this reason, for example, that fingerprinting and iris scans are not accepted in many retail, banking and financial services applications. Dynamic signature verification is a much more easily digested biometric method of identification. The act of signing one's name is socially accepted and commonplace in our legal and commercial lives. As such, individuals are less likely to object to their signature being confirmed as compared to other possible biometric analyses. This allows dynamic signature verification to be seamlessly integrated into existing working processes.

Not only is dynamic signature verification the least controversial of current biometric methods on the market, it is also one of the most accurate, intuitive, fast and cost effective, and operates with compact data. All these factors make it an ideal solution for document authentication and enterprise workflow. Nowadays a wide range of equipment is available for digitizing signatures: palmtop or PDA-type devices, digitizer tablets, pointing devices and smart phones. Biometric signature verification software universally supports any form of pen-enabled input device on which a signature is written.

The solution can support any signature authentication application, from homeland security to banking and retail applications, providing organizations and individuals with enhanced security and control over the documents and transactions that are originated, transacted and stored in today's business environments. Based on state-of-the-art technology, signature verification software extracts maximum data concealed in a biometric signature, captured with a digitizer, and converts the data to information that allows a more reliable detection of forgery than any other solution available on the market, including manual verification.

Given its applications and potential for sophistication without being overly intrusive, dynamic signature verification represents an ideal bridge between the long-recognized practice of signing a document and the reliable authentication and authorization that are increasingly needed for many commonplace activities and transactions.

Dr. Tatiana Vazioulina is with Parascript, a company that employs patented digital image analysis and pattern recognition technologies to extract meaningful information from images.Biometric signature authentication shows promise for securing transactions.