If you bought your phone outside New Zealand, chances are that Internet would not work by default when you topup your mobile phone with a data plan(or other free limited offers). They however have enough information on how to set the Access Point Name(APN) for your phone on the Vodafone New Zealand website here.

Even if your phone model is not on the list, you can look at the information provided for the available models and once you get the general idea of how things work, try it out on yours.

While using Android phones, downloading APNdroid and Quick Settings for free from the Android market will help you disable your internet when you are not using internet over phone. This may be a good idea if you are on a limited bandwidth plan and not monitoring your daily internet usage!

The hosting server upgraded to PHP 5.3 and the version of Mambo available through CPanel would not support PHP 5.x. Joomla 1.5 had installation problems and Drupal, though the basic installation went through seamless, appeared un-intuitive to use. Most of the content is now ported to this new CMS. Thank you Tim, for your quick replies!

Abstract: An algorithm to generate the locus of a circle using the intersection points of straight lines is proposed. The pixels on the circle are plotted independent of one another and the operations involved in finding the locus of the circle from the intersection of straight lines are parallelizable. Integer only arithmetic and algorithmic optimizations are used for speedup. The proposed algorithm makes use of an envelope to form a parabolic arc which is consequent transformed into a circle. The use of parabolic arcs for the transformation results in higher pixel errors as the radius of the circle to be drawn increases. At its current state, the algorithm presented may be suitable only for generating circles for string art.

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Abstract: Orthogonal frequency division multiple access (OFDMA) is becoming a popular technology choice for leading next generation wireless networks. The IEEE 802.16e based systems are the first standardized wireless networks which have incorporated OFDMA. We investigate the use of interference diversity in IEEE 802.16e based networks by considering subchannel formation in different cells. We propose a method for quantifying the interference diversity using suitable arguments and results. Based on these results, a new method for forming subchannels in an 802.16e system is presented.
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Presentation slides(PDF)

Abstract We demonstrate the usefulness of a simple mathematical result- the Chinese Remainder Theorem (CRT). A short informal introduction is followed by a formal analysis of the Chinese Remainder Theorem.Further, we discuss how the Chinese Remainder Theorem can leak information and why caution is to be exercised when applied to a k-threshold system for secret sharing and also for clever RSA variants, namely RSA-CRT and Rebalanced-RSA-CRT.

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Abstract To analyze the RSA encryption algorithm and present a working implementation in python. We discuss the mathematical results and see why the math works. The proofs of various number theoretic results subsequently discussed are available in books mentioned in the bibliography and thus omitted. Detailed discussions on big oh notation, time complexity of basic bit operations, Euclidean and extended Euclidean algorithm, time complexity of Euclidean algorithm, time complexity of extended Euclidean algorithm, linear congruences, Euler totient function, Fermats little theorem, Euler's theorem, the Miller-Rabin test are presented. With this mathematical background we then analyze the RSA algorithm followed by a simplifed example. Finally, the documented python code for the RSA algorithm is presented and is hoped to be of use for serious programmers who intend on implementing the algorithm on a workstation.

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Functionality E-Banking is vulnerable to numerous attacks as it deals with online digital cash transactions. It is hence important to use publicly acclaimed cryptographic algorithms that have been under scrutiny and cryptanalysis for numerous years. We choose a symmetric key cryptosystem such as Blowfish for our implementation. Though encrypted, the transactions between the two banks are still vulnerable to block replay attacks by a man in the middle. To thwart this attack we use a suitable chaining mode such as Cipher Block Chain with checksum (CBCC). A separate Initialization Vector (IV) is generated for chaining each transaction, using a fast Pseudo Random Number Generator (PRNG) with a large period. We use one such PRNG known as Mersenne Twister (MT19937). The public keys of Bank A and Bank B are authenticated by a Certifying Authority (CA). The application is implemented by writing a client and server program using Berkley Sockets. This application assumes the existence of a CA and doesn't implement any Public Key cryptosystem.
report.zip
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testing.zip

Multiplicative congruential generators have been first suggested by D.H.Lehmer as an arithmetic procedure to generate pseudo random numbers. A mild variation of it is the linear congruence generator. Over many years both these generators were widely used in simulations and reported to have good statistical properties and favorable cycle length. Cryptanalysts have come up with numerous complex methods to cryptanalyze the generators mentioned above. We discuss a simple method to cryptanalyze both multiplicative and linear congruence generators, which make them unsuitable as raw input to simulations and various cryptosystem. Note: This work is attributed to [1].

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The man in the middle attack (MITM) on the analog of Massey Omura over Elliptic curves may look confusing but is trivial and is as discussed.

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Elliptic curve cryptography, a few more basics.

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