**3. System Description**

The proposed user identification and verification system is comprised of a software that causes it to function according to the steps illustrated in Figure 1.

In this section, the extraction of hand and bloodstream data is discussed. The entire system commences with obtaining the image of the hand, and then that of the bloodstream (vascular structure) [48,49]. Next, background noise is removed from the images to make it fit for further processing. This process is followed by the first screening process (segmentation) for which every aspect of the scanned object is carefully verified by the system, which tries to match the image with existing or similar saved features (images) within the database. Extracted data from the image moves into a central database where the verification is completed. Next, the score-level fusion is obtained for the image (degree of unanimity) and, depending on the threshold, the user is either successfully verified or not. However, this is often done after the data has been normalized as a function of the number of tests carried out. The rest of this section is described in deeper terms and the different blocks are represented in Figure 1. Furthermore, some useful metrics such as EER is often calculated in order to have a full grasp of the efficiency of the system in comparison to other existing systems.

#### *3.1. Hand Geometry*
