Usually smart card applications base on international standards and norms. Also protocols mentioned here in this blog in context of ePassports, like Supplemental Access Control (SAC) or Password Authenticated Connection Establishment (PACE) are based on international ISO standards. The following figure shows the relevant ISO standards for contacted smart cards on the one side and contactless smart cards on the other side:
Smart Cards in context of ISO/OSI Layer Model
The main standard for contacted smart cards is ISO 7816, the main standard for contactless smart cards is ISO 14443. On application level both types of smart cards are using ISO 7816, where all commands (Application Protocol Data Unit, APDU) and files systems are described. Protocols are composed by these commands and using access rights and file systems specified in this standard. The standard ISO 7816-4 (Integrated circuit cards – Part 4: Organization, security and commands for interchange) is important for nearly all smart card applications. Using this standard enable applications to interoperate in various open environments, e.g. a credit card can be read by different terminals all over the world because credit card and terminal are using the same standard.
ISO 14443 specifies contactless mechanisms of smart cards. Smart cards may be type A or type B, both of them communicate via radio at 13.56 MHz. The main differences between these two types concern modulation methods, coding schemes (ISO 14443-2) and protocol initialization procedures (ISO 14443-3). Both types are using the same transmission protocol, described in ISO 14443-4. The transmission protocol specifies mechanisms like data block exchange and waiting time extension. In the contactless world a reader is called proximity coupling device (PCD) and the card itself is
called proximity integrated circuit card (PICC).
During the last months I spent some hours in the specifications of EnOcean telegrams. These telegrams are used in domain of home automation. The EnOcean Alliance publishes all necessary specification on their website. One of the relevant specifications is EnOcean Serial Protocol 3 (ESP3). In this description you can find all information to understand the protocol used by EnOcean.The specification of this protocol is also standardized and published as ISO/IEC 14543-3-10.
If you are interested in collecting telegrams to analyze them and to understand the protocol behind them, the following project may be interesting for you: EnOceanSpy. I’ve hosted this small piece of software on GitHub. It’s written in C and there is a binary version available for Raspberry Pi (RasPi). On this way you can use your RasPi in combination with an USB300 stick. The following photo demonstrates a buildup including a WakaWaka as power source.
EnOcean allows on the one hand one-way and on the other hand bidirectional communication between devices. Currently most of this communication is not decrypted, so you can read all information communicated via air. There is a first specification to use cryptography for EnOcean protocol. I will give you an overview on this way of encryption in the next time.
Have fun to seek your environment after EnOcean devices
The colleagues of testevents.com set up a list of upcoming test events all over the world (testing in general and not only focussing on protocols). You can filter for several countries or categories and get information concerning corresponding call for papers. The calendar lists various test events, e.g. German Testing Day taking place in November 2013 in Munich or EuroStar Software Testing Conference taking place in November 2013 in Gothenburg, Sweden.
This list may help you to plan your attendance at important conferences and to keep the deadlines of CfP in mind. On their website you can also find some book references and magazine references, all focusing on testing. Thanks to the team of testevents.com for this useful service!
Back in office after three weeks holiday I would like to show you now one of the high level results doing all these interoperability tests in the domain of ePassports. Today a German consortium (i.a. Bundesdruckerei and Secunet) won a tender for biometric-based eGates rolled out across the country in the next years at several airports. These eGates use well-known protocols as Basic Access Control (BAC) or Supplemental Access Control (SAC) to establish a secure channel between reader and smart card of ePassport via ISO 14443 interface for contactless smart cards. An automatic border control (ABC) like this allows passengers in less than 30 seconds to pass the gate. Currently you can find an alternative of such systems at the airport in Heathrow.
The following figure shows a typical simplified workflow of such a border control system:
To reduce waiting time for passengers the system is using an automatic process. At the beginning the citizen is passing the gate by showing his ePassport. An inspection system scans the machine readable zone of the data page to derivate a cryptographic key to get access to the contactless smart card. As soon as all data groups of chip are read, the inspection system verifies the authenticity of the data to assure validity of the current ePassport chip. In the meantime the face recognition system scans the citizen to get a facial image of him. This image is being compared with the facial image of the chip (biometric verification). If both images are similar and the ePassport is not blacklisted, the citizen can pass the gate.
The colleagues of Imbus started a new platform with a list of several test tools in various categories. You find there both commercial and open source solutions of test software. The list is available in German and also in English. All listed tools are classified as following:
- Code and coverage analysis
- Continuous integration
- Defect and change management
- Load and performance test
- Test automation
- Test management
- Test specification and generators
You are invited to submit your tool and to interchange experiences and tips on the platform. Thanks to Imbus for this great and helpful overview!