LPKI - A Lightweight Public Key Infrastructure for the Mobile Environments

The non-repudiation as an essential requirement of many applications can be provided by the asymmetric key model. With the evolution of new applications such as mobile commerce, it is essential to provide secure and efficient solutions for the mobile environments. The traditional public key cryptography involves huge computational costs and is not so suitable for the resource-constrained platforms. The elliptic curve-based approaches as the newer solutions require certain considerations that are not taken into account in the traditional public key infrastructures. The main contribution of this paper is to introduce a Lightweight Public Key Infrastructure (LPKI) for the constrained platforms such as mobile phones. It takes advantages of elliptic curve cryptography and signcryption to decrease the computational costs and communication overheads, and adapting to the constraints. All the computational costs of required validations can be eliminated from end-entities by introduction of a validation authority to the introduced infrastructure and delegating validations to such a component. LPKI is so suitable for mobile environments and for applications such as mobile commerce where the security is the great concern.Comment: 6 Pages, 6 Figure

Pendekatan konstruktif dalam inovasi pengajaran dan pembelajaran Bahasa Melayu di Kolej Vokasional

Pendekatan konstruktif adalah pendekatan pengajaran dan pembelajaran yang berpusatkan pelajar manakala inovasi pengajaran pula dikaitkan dengan kaedah pengajaran yang terbaru demi mengukuhkan pemahaman pelajar. Pembelajaran berasaskan pendekatan konstruktif merupakan elemen yang penting dan perlu difahami oleh guru-guru bagi memantapkan proses pengajaran dan pembelajaran sesuai dengan peredaran masa dan menjayakan proses tranformasi pendidikan negara. Objektif kajian ini dijalankan untuk mengenal pasti pemahaman guru-guru bahasa Melayu berkaitan inovasi, mengenal pasti perbezaan yang wujud antara guru lelaki dan guru perempuan dalam mengamalkan inovasi, pengkaji juga melihat adakah wujud perbezaan antara guru baru dan guru yang sudah berpengalaman dalam aspek mengaplikasikan inovasi serta mengenal pasti kekangan-kekangan yang dialami oleh para guru untuk mengaplikasikan inovasi di sekolah. Seramai 63 orang guru bahasa Melayu dari lapan buah kolej vokasional telah dipilih sebagai responden dalam kajian ini. Data dianalisis menggunakan perisian Winsteps 3.69.1.11 dengan pendekatan Model Pengukuran Rasch. Hasil analisis menunjukkan bahawa guru�guru bahasa Melayu memahami kepentingan inovasi dalam pengajaran dan pembelajaran. Hasil kajian juga menunjukkan guru-guru perempuan lebih banyak menerapkan unsur inovasi dalam pengajaran berbanding guru lelaki. Walaupun begitu, aspek pengalaman tidak menunjukkan perbezaan dari segi pengamalan inovasi sama ada guru baru ataupun guru yang sudah berpengalaman. Pengkaji juga mengenal pasti beberapa kekangan yang dialami oleh guru-guru untuk mengamalkan inovasi ini. Sebagai langkah untuk menangani masalah berkenaan, beberapa cadangan telah dikemukakan oleh pengkaji bagi memastikan guru-guru dapat merealisasikan proses pengajaran berkesan dengan penerapan inovasi mengikut model pendekatan konstruktif. Pengkaji berharap, kajian ini dapat dijadikan sebagai satu panduan kepada pelaksana kurikulum bagi memastikan budaya inovasi sentiasa menjadi amalan dalam kalangan guru demi mengangkat profesionalisme guru di Malaysia

Improving Air Interface User Privacy in Mobile Telephony

Although the security properties of 3G and 4G mobile networks have significantly improved by comparison with 2G (GSM), significant shortcomings remain with respect to user privacy. A number of possible modifications to 2G, 3G and 4G protocols have been proposed designed to provide greater user privacy; however, they all require significant modifications to existing deployed infrastructures, which are almost certainly impractical to achieve in practice. In this article we propose an approach which does not require any changes to the existing deployed network infrastructures or mobile devices, but offers improved user identity protection over the air interface. The proposed scheme makes use of multiple IMSIs for an individual USIM to offer a degree of pseudonymity for a user. The only changes required are to the operation of the authentication centre in the home network and to the USIM, and the scheme could be deployed immediately since it is completely transparent to the existing mobile telephony infrastructure. We present two different approaches to the use and management of multiple IMSIs

A cooperative cellular and broadcast conditional access system for Pay-TV systems

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2009 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.The lack of interoperability between Pay-TV service providers and a horizontally integrated business transaction model have compromised the competition in the Pay-TV market. In addition, the lack of interactivity with customers has resulted in high churn rate and improper security measures have contributed into considerable business loss. These issues are the main cause of high operational costs and subscription fees in the Pay-TV systems. As a result, this paper presents the Mobile Conditional Access System (MICAS) as an end-to-end access control solution for Pay-TV systems. It incorporates the mobile and broadcasting systems and provides a platform whereby service providers can effectively interact with their customers, personalize their services and adopt appropriate security measurements. This would result in the decrease of operating expenses and increase of customers' satisfaction in the system. The paper provides an overview of state-of-the-art conditional access solutions followed by detailed description of design, reference model implementation and analysis of possible MICAS security architectures.Strategy & Technology (S&T) Lt