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	<front>
		<journal-meta>
			<journal-id journal-id-type="publisher-id">INFORMATICA</journal-id>
			<journal-title-group>
				<journal-title>Informatica</journal-title>
			</journal-title-group>
			<issn pub-type="epub">0868-4952</issn>
			<issn pub-type="ppub">0868-4952</issn>
			<publisher>
				<publisher-name>VU</publisher-name>
			</publisher>
		</journal-meta>
		<article-meta>
			<article-id pub-id-type="publisher-id">inf14108</article-id>
			<article-id pub-id-type="doi">10.15388/Informatica.2003.008</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Research article</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Simple Generalized Group‐Oriented Cryptosystems Using ElGamal Cryptosystem</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="Author">
					<name>
						<surname>Yang</surname>
						<given-names>Chou‐Chen</given-names>
					</name>
					<email xlink:href="mailto:ccyang@mail.cyut.edu.tw">ccyang@mail.cyut.edu.tw</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>Chang</surname>
						<given-names>Ting‐Yi</given-names>
					</name>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>Li</surname>
						<given-names>Jian‐Wei</given-names>
					</name>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
				</contrib>
				<aff id="j_INFORMATICA_aff_000">Department and Graduate Institute of Computer Science and Information Engineering, Chaoyang University of Technology, 168, Gifeng E. Rd., Wufeng, Taichung County, Taiwan 413, R.O.C.</aff>
			</contrib-group>
			<contrib-group>
				<contrib contrib-type="Author">
					<name>
						<surname>Hwang</surname>
						<given-names>Min‐Shiang</given-names>
					</name>
					<email xlink:href="mailto:mshwang@mail.cyut.edu.tw">mshwang@mail.cyut.edu.tw</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_001"/>
				</contrib>
				<aff id="j_INFORMATICA_aff_001">Department of Information Management, Chaoyang University of Technology, 168, Gifeng E. Rd., Wufeng, Taichung County, Taiwan 413, R.O.C.</aff>
			</contrib-group>
			<pub-date pub-type="epub">
				<day>01</day>
				<month>01</month>
				<year>2003</year>
			</pub-date>
			<volume>14</volume>
			<issue>1</issue>
			<fpage>111</fpage>
			<lpage>120</lpage>
			<history>
				<date date-type="received">
					<day>01</day>
					<month>12</month>
					<year>2002</year>
				</date>
			</history>
			<abstract>
				<p>In the generalized group‐oriented cryptosystem, the sender can send a conditional message to a group of users such that only the specified sets of users in this group can cooperate to decrypt this message. In this paper, we will use an ElGamal cryptosystem and an elliptic curve ElGamal cryptosystem to achieve the purposes of generalization and group‐orientation, respectively. Both of our schemes are more efficient than Tsai et al.'s scheme in terms of sender's computational complexity.</p>
			</abstract>
			<kwd-group>
				<label>Keywords</label>
				<kwd>Diffie–Hellman scheme</kwd>
				<kwd>ElGamal cryptosystem</kwd>
				<kwd>elliptic curve cryptosystem</kwd>
				<kwd>group‐oriented cryptosystem</kwd>
			</kwd-group>
		</article-meta>
	</front>
</article>