Abstract: With the growth of utilization of mobile cellular telephones, smart-cards and pager devices, the development of cryptography systems to protect the information transmitted and received by these appliances is becoming more important every day. These systems should be capable of working efficiently using the limited resources of memory and processing offered by these appliances and, at the same time, yield a high degree of protection against possible attempts to violate the secrecy of the information. In modern cryptography systems it is common the combination of secret key (symmetric) and public key (assymmetric) cryptography techniques. A new standard for secret key cryptography known as Rijndel was recently adopted by NIST (USA) and should become the industry standard soon as it offers a good level of security among other qualities. This work investigated performance figures and memory consumption of the Rijndael algorithm for various combinations of its parameters. The main goal was to provide enough information for projects that use this algorithm in devices with limited resources. The results show that Rijndael can have a low memory consumption profile associacted with a good performance and, therefore, they can guide more sophisticated projects for security environments for low computational capacity devices.

Keywords: Symmetric Cryptography - restricted computer environments Rijndael algorithm

Abstract: We present in this final report of the project granted by Fapesp, Processo n^o 00/09619-3, a 3D cursor, an instance for free movements in 3D space, in an analogous way of 2D cursors in 2D graphics environment. To have a clear interaction interface between 2D input devices and our 3D cursor, we also introduce the module MTKX, an extension for the toolkit MTK, for unifying the interface between an application and a window management system.

Keywords: 3D Cursors, 3D Direct Manipulations, Interaction Toolkits, HCI