We highly recommend sticking to standards wherever they materialize. Sticking to standards is the best way to design a modular system and be able to replace hardware or software modules that don't satisfy your needs. Sticking to the standards keeps you independent of smart card or reader manufacturers. While nothing is more important than a good and healthy relationship with your suppliers, hardware and software interfaces should be defined according to standards, whenever they exist.
The following list contains links to important smart card-related standards:
ISO7816 identification card standard from the International Organization for Standardization.
ISO 14443 RFID cards; contactless proximity cards operating at 13.56 MHz in up to 5 inches distance.
ISO 15693 RFID cards; contactless vicinity cards operating at 13.56 MHz in up to 50 inches distance.
EMV 2000 version 4.00, Europay, MasterCard and Visa worked jointly over the last few years to develop specifications that define a set of requirements to ensure interoperability between chip cards and terminals on a global basis, regardless of the manufacturer, the financial institution, or where the card is used. The latest version of the specifications, EMV 2000 version 4.0, was published in December 2000. It is envisaged that the specifications will in the near future be supplemented with support for lower voltage cards and a definition of a contact-less interface to EMV chip cards.
PC/SC Builds upon existing industry smart card standards - ISO7816 and EMV - and complements them by defining low-level device interfaces and device-independent application APIs as well as resource management, to allow multiple applications to share smart card devices attached to a system.