When we talk about transport ticketing, Calypso is the technology we must discuss first. Calypso is a transport ticketing system built by the transport operators. It was designated to match the transport ticketing requirements from functional flow to security mechanisms. The main identifier of Calypso is that it requires a micro processor card. This enables all the security required by complex transportation environment.
So, what is Calypso?
Calypso is a ticketing application developed and maintained by Calypso Association. Calypso Association, based in Brussels, Belgium, was established by RATP and technology provider Innovatron in 1993. Later on, group of European transport operators from Belgium, Germany, France, Italy and Portugal joined the association. Calypso ticketing application is currently being used by various European public transport systems.
In the Calypso world, you can define various players into a single card (now the term “portable object” is used though, rather than “the card”) and they can share the same balance. The technical design of the application supports multi-application by nature. Different contracts can be installed on to a single card which are protected by different key sets. Each Calypso chip has a set of derived keys from master keys. DES and DESX (an implementation of DES against brute force attacks) can be used for authentication. Calypso requires its own SAM card for authentication which is a pre-requisite of modifying the data in the chip.
Unlike typical mifare designs, you are restricted by the boundaries and transaction flow developed by Calypso, but it covers almost anything that can be expected in a transport ticketing environment. Calypso applet runs on micro processor chips, so authentication is quite strong (and fast)
Calypso Association plays an innovative role towards the NFC era and they seem to be ready for the NFC evolution. (I wish I could say revolution, by the way) Calypso applet runs on various card operating systems varying from Infineon to Watchdata chips, including NXP’s JCOP family. Of course this includes any secure element in the NFC world.
Based on my personal experience, I can say that Calypso is an equivalent of EMV in the banking payment world. Both of the applications are quite well designed, already running on millions of chips and getting ready for the future.