A User Centric Security Model for Tamper-Resistant Devices

2.5 Case Studies
issued the application). The bank can opt for certain user credentials (e.g. PIN, password,
or biometric) that the bank's application on the UCTD can ask the user to authenticate
herself. Therefore, authentication details do not need to be communicated over the internet.
The UCTD then provides dynamic authentication and if required can provide a transaction
certicate to the merchant as is done in POS transactions [9], eectively avoiding poor
technical-security and security-usability along with privacy issues discussed in [76][78].
2.5.4 Online Gaming
In April 2011, the security breach of the Sony PlayStation Network and Qriocity services
that revealed private information regarding an estimated 70 million users [79] was in the
news. This breach has shown that big networks that store user's private data are the
prime targets for malicious users. In this section, we are not going to provide a solution to
the problems faced by Sony in this security breach but look at how a UCTD can reduce
the clustering of large data at one point (i.e. on SP's servers) which provides a potential
motivation for attack (i.e. economics of attack 2 ) [80].
Therefore, for this case study, we consider a Company A that oers an online gaming
platform, and games store to its customers. The objectives of Company A are: (1) to
ensure that customers can be uniquely identied and their credentials can be validated,
(2) to ensure customers get the services for which they are authorised, and nally (3) to
ensure that customers can make purchases while being logged onto the games store or
online-gaming platform.
Company A oers an application that a user can download onto her UCTD. The download
application is personalised to the user. It has the user's name, email address, and
postal address (if necessary). The user identity at Company A's server is identied by a
unique user identity (i.e. it is a pseudo-identity that does not have any obvious link to
the user). The user has her password stored on her UCTD rather than on Company A's
server; therefore, when the user tries to access Company A's resources, she provides her
password to the UCTD. We do not delve into the details of how the user identication and
authentication will be carried out using a UCTD in our case study, but similar mechanisms
are already in operation, for example the EMV Dynamic Data Authentication (DDA) or
Combined DDA (CDA) mechanisms [9] (i.e. card transactions at a POS). This will allow
Company A to identify and authenticate their customer. In addition, the service privileges
associated with the user are also stored in the application. Therefore, Company A does
not have to store any of these details at a centralised location as they are already stored
on a tamper-resistant device as part of the Company A's application.
2 Cost-benet comparison of a potential attacks and outcome from it is referred as economics of attack.
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