Calypsonet Terminal Calypso API

The Calypsonet Terminal Calypso API is an extension of the Calypsonet Terminal Reader API which provides a high-level API standardizing the way to interact with a Calypso® product (card, NFC smartphone applet/application, SAM, etc…).


The Calypso API provides the means to select a target card or SAM and then perform a transaction with the selected target.

  • The result of a card selection is a smartcard image whose file structure and data records can be browsed.
  • The result of a SAM selection is a smartcard image whose keys' parameters can be read.
  • A transaction with a target card or SAM may involve a master SAM in order to secure the operations.

The CalypsoCard & CalypsoSam interfaces provide ‘getters’ in order to recover the information of the selected smartcard.

To optimize the number of exchanges with a card reader of a SAM reader, the Calypso API allows to group the commands. A set of command could be first ‘prepared’, and then be ‘processed’ by a selected target at the selection or during the transaction. A transaction with a Calypso PO is fully managed through the PoTransaction object:

Calypso API - class diagram

Selection of a Calypso card

A Calypso card selection could be defined to accept or not invalidated card.

Through the selection only basic Select File (without changing DF) or Read Records commands could joined: the goal is to recover in the selection result some file status or record data of elements present in all cards of a ticketing networks. The type of card product has not yet been identified, the commands are prepared to be supported by all types of card products: Prime, Ligth, or Regular.

Then if a Calypso card has matched the selection request, a Calypso card image is returned, some file headers or file records could be filled depending on the information recovered in the responses of the Select File or Read Records processed.

Transaction with a Calypso card

Except the operations involving secure processing on “data” (data signature computation / verification, data ciphering / unciphering), only commands for the card need to be prepared though the Card Transaction Manager interface. Depending on the operation, if necessary the security involving the master SAM must be controlled internally by the Calypso library.

Simple operation outside a session

PIN verification outside a session

Data secure processing outside a session

Key update outside a session

Stored Value operation outside a session

Simple secure session

In most of the cases, it should be possible to handle a secure session with a Calypso card, using only:

  • 3 exchanges with the card reader (selection processing, session opening processing, and session closing processing),
  • and 3 exchanges with the SAM reader (terminal session challenge recovery, session MAC computation, and card authentication).

Calypso API - Simple Secure Session - Sequence Diagram

PIN verification inside a session

Data secure processing inside a session

Stored Value operation inside a session

Multiple secure sessions

Selection of a Calypso SAM

Transaction with a Calypso SAM

Implementations & API Documentation

The third version number (x.y.z) only concerns updates of the javadoc because this component does not contain any implementation, but only an API. Therefore, it is recommended to always perform a dynamic import as described above in order to have the most up-to-date documentation.

Calypso API in Java

All deliverables are available directly from the Maven Central Repository or by using one of the project resource managers below:

implementation 'org.calypsonet.terminal:calypsonet-terminal-calypso-java-api:1.1.+'

Calypso API in C++