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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">INFO1046</article-id><article-id pub-id-type="doi">10.15388/Informatica.2015.42</article-id>
			<article-categories>
				<subj-group subj-group-type="heading"><subject>Article</subject></subj-group>
			</article-categories>
			<title-group>
				<article-title>Event-Based Awareness Services for P2P Groupware Systems</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="Author">
					<name>
						<surname>Poulovassilis</surname>
						<given-names>Alex</given-names>
					</name><email xlink:href="mailto:ap@dcs.bbk.ac.uk">ap@dcs.bbk.ac.uk</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/><xref ref-type="corresp" rid="thanks1">*</xref>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>Xhafa</surname>
						<given-names>Fatos</given-names>
					</name><email xlink:href="mailto:fatos@lsi.upc.edu">fatos@lsi.upc.edu</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_001"/>
				</contrib>
				<contrib contrib-type="Author">
					<name>
						<surname>O’Hagan</surname>
						<given-names>Thomas</given-names>
					</name><email xlink:href="mailto:trohaga@outlook.com">trohaga@outlook.com</email>
					<xref ref-type="aff" rid="j_INFORMATICA_aff_000"/>
				</contrib>
				<aff id="j_INFORMATICA_aff_000">
					London Knowledge Lab, Birkbeck, University of London, UK
				</aff>
				<aff id="j_INFORMATICA_aff_001">
					Universitat Politècnica de Catalunya, Spain</aff>
				</contrib-group>
			<author-notes>
				<corresp id="thanks1">
					<label>*</label>
					Corresponding author.
				</corresp>
			</author-notes>
			<pub-date pub-type="epub"><day>01</day><month>01</month><year>2015</year></pub-date><volume>26</volume><issue>1</issue><fpage>135</fpage><lpage>157</lpage>
     <history>
       <date date-type="received"><day>01</day><month>01</month><year>2014</year></date>
       <date date-type="accepted"><day>01</day><month>09</month><year>2014</year></date>
     </history>			<permissions>
				<copyright-statement>Vilnius University</copyright-statement>
				<copyright-year>2015</copyright-year>
			</permissions>
			<abstract>
				<label>Abstract</label>
				<p>P2P systems enable decentralised applications for supporting collaborating groups and communities, where the collaboration may involve both sharing of data and sharing of group processes among group members. In such applications, monitoring and awareness are critical functionalities required for an effective collaboration. However, to date there has been little research into providing generic, application-independent awareness in P2P groupware systems. We present a distributed event-based awareness approach for such systems that provides different forms of awareness through a set of interoperating, low-level awareness services. The user and technical requirements for the approach are motivated with reference to Project-Based Learning in a P2P environment. We describe the implementation of a superpeer P2P network on a Cloud platform and the provision of reliable awareness services (AaaS – <italic>Awareness as a Service</italic>) from the Cloud. We report on the outcomes of an empirical evaluation of the performance and scalability of the approach.</p>
				</abstract>
			<kwd-group>
				<label>Keywords</label>
				<kwd>P2P systems</kwd>
				<kwd>collaboration</kwd>
				<kwd>awareness</kwd>
				<kwd>services</kwd>
				<kwd>cloud computing</kwd>
				<kwd>awareness as a service (AaaS)</kwd>
			</kwd-group>
		</article-meta>
	</front>
</article>
