Personal handwritten signature is the most common and widely accepted way of proving individual or mutual consent of the parties involved in any written agreement.
From a legal perspective a handwritten signature has a stronger enforceability as an electronic signature, compared to other commonly accepted electronic signatures such as a PIN code or a password or a scanned signature file. That's because handwritten signature alerts the signer that he or she is about to ascribe legal consequences to his or her actions. The act of placing a signature signals the intent to assume obligations in a way which may not be apparent from, for instance, entering a PIN code. This is an important component in contract formation, since contracts, as a principle, are entered into by the mutual consent of the parties. The act of signing helps in proving the willingness of the signatory to be bound by legal obligations and therefore deducing consent.
In addition, each handwritten signature of a person is unique and is done by the sole control and free will of the signer.
The handwritten signature is not only the graphic shape display (x,y curve), there are some other attributes, such as: speed, accelerations, angles, pressure (depending on the device) and more, which together construct a unique (behavioral) biometric object. The handwritten signature is an admissible evidence in a legal proceedings. Being a biometric object, it is a subject to forensic analysis of a handwriting expert and may be considered a strong evidence.
In order to perform biometric signature authentication, AKA Dynamic Signature Verification (DSV), as in all other biometric methods, user enrollment phase is required.
The user, in this case, the individual signer needs to enroll in the system. The result of the enrollment process is a Signer-Profile which is the reference base for verifying the signer’s signatures from that moment on.
During the enrollment, the signer needs to provide 5 consistent samples of her / his handwritten signatures. CAS will tolerate up to 10 signature samples entry, in case the signer fails to complete the 5 consistent signatures required for the profile, she / he needs to start a new enrollment process.
Once enrollment has completed successfully, the signer’s profile is encrypted and stored anonymously in the server. The signer receives a unique identification code (GUID) which is used to retrieve the profile, whenever signature verification is requested for this signer, in a business process, which requires signer authentication as a business rule.
CAS has a comprehensive documented API which is provided in two layers.
Server Web API – A set of web-services which enable full-function interaction of a business application with the services provided by the server in the following categories: Organization, Profile, Administration, and Verification. The API implementation is documented by video guidance in English.
Signature Pad API – This API provides a set of web services which can be used in any web application for embedding the virtual touch screen pad. The virtual pad interacts with the CAS using the Web API, in order to enroll or verify a signer. Using the SignaturePadApi releases the application developer from the need to use a custom-developed virtual signing pad, and use an out-of-box HTML based virtual pad instead. This API is documented and also has video based guide.
If you would like to experience using electronic handwritten signature for personal authentication, or invite a colleague to give it a try, just click on the selected button here (smartphone or any other touch-screen device is required). Bon voyage!