PKCS#15 defines a standard allowing users of cryptographic tokens to identify themselves to applications, independent of the application’s Cryptoki implementation (PKCS#11) or other API. RSA has relinquished IC-card-related parts of this standard to ISO/IEC 7816-15.
PKCS#15 and the more recent ISO/IEC 7816-15 standards describes a method of finding the files, objects and features of file based smart cards. ISO/IEC 7816-4 describes a framework for implementing and using file based cards, but it does not describe how to discover which files, objects and features are contained on the personalized card.
Cryptographic tokens, such as Integrated Circuit Cards (IC cards or “smart cards”), are capable of providing a secure storage and computation environment for a wide range of user credentials such as keys, certificates and passwords. Because of this, it is widely recognized that they offer great potential for secure identification of users of information systems and electronic commerce applications. For a general introduction to IC cards and their use.
PKCS #15 has been designed in such a way that the standard can be implemented on any smart card with basic ISO/IEC 7816 compatibility. For example, no assumptions about IC card commands except those defined in ISO/IEC 7816-4 have been made. In fact, it should even be possible to implement it on memory cards and software tokens.