A User Centric Security Model for Tamper-Resistant Devices

1.3 Motivation and Challenges
computing device the consumer is using. The user and the bank get security and privacy
protection from the UCTD regardless of the device (e.g. computer, mobile phone, tablet,
and POS, etc.) from wherever they are connecting to the payment network. Therefore,
feature-rich computing devices can have applications that rely on the services provided by
the UCTD to enable a security- and privacy-preserving framework.
For such a device, we consider that smart cards oer the most promising architecture.
In our opinion, the rigorous design and analysis constituted in the smart card industry
can benet other computing environments by providing security, privacy, and reliability
services. If we port the smart card architecture as a generic tamper-resistant device that
can interface with dierent computing environments then it can provide a ubiquitous,
interoperable, exible, dynamic, secure, and reliable architecture that can store and execute
security- and privacy-sensitive applications. In this thesis, we use the term smart card as
inclusive of the technology (both hardware and software architecture) and without any
restriction on form factors. The smart card architecture can only be realised as a UCTD
if the associated ownership issues are resolved.
The most prominent ownership model in the smart card industry is centred on the organisation,
which acquires smart cards from card manufacturers and issues them to the
customers. Such organisations are referred to as card issuers and in this thesis this ownership
model is called the Issuer Centric Smart Card Ownership Model (ICOM). This model
provided much needed momentum in the smart card industry, driving the technological and
infrastructural improvements to provide better, more secure and reliable services to customers.
It also enabled the initial motivation for standardising the smart card technology
(e.g. ISO 7816 [24], ISO 14443 [25]) and its applications for specic elds (e.g. GSM [26],
EMV [9] and ITSO [27], etc.).
The ICOM architecture is restrictive and might not be suitable for smart cards if they are
to be adapted as UCTDs. Therefore, we propose a model that provides a more exible,
and dynamic platform which also gives control of the smart card to its users. This model is
referred to as the User Centric Smart Card Ownership Model (UCOM). The term ownership
(control) in the proposed model means freedom of choice that gives a UCTD owner the
privilege of installing or deleting any application as they desire. However, this does not
mean that they have the ownership of individual applications installed on the device [10].
The application(s) installed on the smart card will always be under the total control of
the application issuers (i.e. the SPs) and the user will be entitled to use these applications
under sanction from their respective SPs. Furthermore, the choice about whether to lease
an application to a card (user) resides solely with the relevant SP. Therefore, we can dene
a UCTD as a device whose architecture is based on the smart card technology that supports
the UCOM framework.
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