Some organizations choose to embed a digital signature onto a USB token or smart card for security reasons. Often this type of setup is found in companies which have employees sharing computers and workstations. When computers are shared it could create a situation that allows someone else to have access to their files, email and other corporate resources. However, by using a USB token or smart card, users must provide the necessary certificates in order to authenticate and access data and resources.
How a Digital Certificate Is Accessed When It Is Placed on a USB Token or Smart Card
When a digital certificate is embedded onto a smart card or USB token it must be read by the computer before access is granted for specific resources. For example, with a USB token, the user must insert the portable USB drive into an available USB slot on the computer. Anytime the user is prompted to supply the certificate they direct the computer to find it on the USB drive. In cases where a smart card is used instead, the user simply scans their card through an attached smart card reader to provide the required certificate.