a new architecture for secure two-party mobile payment transactions

Java ME/CLDC: java.math.BigInteger and java.security.SecureRandom (Rittinghouse &
Ransome, 2004). These two classes have the same names as the core classes in Java SE but
function differently to the core Java classes in Java SE. A collision will occur when JDK is
used to compile the code importing these two classes. To avoid this collision, one method
is to employ some software such as Proguard 4 to make an obfuscation on the code. The
compiler is able to find the target classes without confusing the different classes with the
same name, then avoids the conflict that occurred.
In developing SA2pMP, the Bouncy Castle Cryptography with version of 1.42 was
employed. The implementation of cryptography algorithms makes use of the Java ME
lightweight API package in Bouncy Castle. Proguard is employed in the development as
indicated above. Proguard 4.0 has already been bundled in NetBeans IDE, so this was an
easy choice.
5.2 Simulation Implementation
A mobile bank is employed as a scenario for system simulation. The banking transaction
of money transfer is assumed to describe how the system works. Readers should notice that
in the following:
• “− >” means a data transfer process.
• “+” means a data combination operation. In this implementation, most + operations
denotes simple concatenation of the strings.
4 http://proguard.sourceforge.net/
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