Md. Saifuddin Khalid

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This paper proposes a Multi-Code Multi-Carrier Code Division Multiple Access (CDMA) scheme for next generation wireless communication systems. This system retains the advantages of Multi-Carrier CDMA in combating multipath and rejecting interference, and provides variable and adaptive data rates through the use of Multi-Code scheme. The rate adaptation(More)
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—The two important aspects of security that deal with transmitting information or data over some medium like Internet are steganography and cryptography. Steganography deals with hiding the presence of a message and cryptography deals with hiding the contents of a message. Both of them are used to ensure security. But none of them can simply fulfill the(More)
The Vigenère Cipher is a traditional method which involves encrypting alphabetic text by using a series of different Caesar Ciphers based on the letters of a keyword. The Vigenère Cipher works on the set of 26 English alphabets. In this paper we introduce the Alpha-Qwerty Cipher and reverse Alpha-Qwerty Ciphers which are the extensions to the Vigenère(More)
One major difficulty faced by organizations is the protection of data against malicious access. Six security mechanisms, namely, authentication, authorization, access control, auditing, encryption and integrity control are available in Oracle 10g database management systems (DBMS). These are implemented for protecting data. These typical database security(More)
Digital libraries are fast expanding into the role of independent educational entities that aspire not only to complement traditional classroom teaching, but also allow remote access to Learning Objects. Multifaceted roles of Learning Objects can be realized only if the course content and the related content management system are versatile enough to be(More)
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