5,076 research outputs found

    Economic barriers to development : cost of access to internet infrastructure

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    The Internet is increasingly viewed as an "indispensable" resource for general development and economic growth (UNDP 1999). Its adoption by governments, organizations and individuals has resulted in the shrinking of spatial and temporal distances between different regions of the world, and has greatly facilitated the "free" and quick exchange of information. Such constrictions of time and space impact upon social and economic interactions at all levels of society. Furthermore, ramifications of this impact are felt by a society, group or individual irrespective of whether or not they use the Internet. The ability to access the Internet, and in particular the costs associated with such access, are therefore important points of consideration. Not only do these costs contribute to the disproportional spread of the Internet across the world's population; they also potentially contribute to uneven patterns of development within, and between countries

    Hybrid Spam Filtering for Mobile Communication

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    Spam messages are an increasing threat to mobile communication. Several mitigation techniques have been proposed, including white and black listing, challenge-response and content-based filtering. However, none are perfect and it makes sense to use a combination rather than just one. We propose an anti-spam framework based on the hybrid of content-based filtering and challenge-response. There is the trade-offs between accuracy of anti-spam classifiers and the communication overhead. Experimental results show how, depending on the proportion of spam messages, different filtering %%@ parameters should be set.Comment: 6 pages, 5 figures, 1 tabl

    Improving the efficiency of spam filtering through cache architecture

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    Blacklists (BLs), also called Domain Name Systembased Blackhole List (DNSBLs) are the databases of known internet addresses used by the spammers to send out the spam mails. Mail servers use these lists to filter out the e-mails coming from different spam sources. In contrary, Whitelists (WLs) are the explicit list of senders from whom e-mail can be accepted or delivered. Mail Transport Agent (MTA) is usually configured to reject, challenge or flag the messages which have been sent from the sources listed on one or more DNSBLs and to allow the messages from the sources listed on the WLs. In this paper, we are demonstrating how the bandwidth (the overall requests and responses that need to go over the network) performance is improved by using local caches for BLs and WLs. The actual sender\u27s IP addresses are extracted from the e-mail log. These are then compared with the list in the local caches to find out if they should be accepted or not, before they are checked against the global DNSBLs by running \u27DNSBL queries\u27 (if required). Around three quarters of the e-mail sources have been observed to be filtered locally through caches with this method. Provision of local control over the lists and lower search (filtering) time are the other related benefits. © 2008 IEEE

    Is There a "Right" Charging Principle with the NGN Advent?

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    Historically, telecommunications services developed adding one network to another (voice and data networks), but Next Generation Networks (NGN) are developing as native multiservice networks. Main characteristics include: broadband capacity, IP protocol, ability to transmit voice, data and video, quality control, separation among different network layers. The fact to deliver with one only network different services such as voice and data, now treated in a very different way with respect to charging principles (interconnection for voice, peering for Internet exchanges), poses the problem of the charging model to adopt in the future. In the paper we will analyse pros and cons of the different charging principles, both at wholesale and retail level, from an economic perspective. The first conclusion is that there is no "magic solution", as any criteria has pros and cons, but that it appears more appropriate to leave operators to choose their retail models, once the wholesale criteria are settled. Then the paper concentrates on the different scenarios which can arise choosing different charging principles at wholesale level. Particular attention is given to the issues of quality safeguard and of recovering nvestments in innovative networks and services. On many aspects "intermediate" scenarios seem better to answer economic problems than the "pure" scenarios, (calling party network pays for all wholesale services, including Internet/data, or bill & keep for everything, including voice).NGN, charging principles.

    Command & Control: Understanding, Denying and Detecting - A review of malware C2 techniques, detection and defences

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    In this survey, we first briefly review the current state of cyber attacks, highlighting significant recent changes in how and why such attacks are performed. We then investigate the mechanics of malware command and control (C2) establishment: we provide a comprehensive review of the techniques used by attackers to set up such a channel and to hide its presence from the attacked parties and the security tools they use. We then switch to the defensive side of the problem, and review approaches that have been proposed for the detection and disruption of C2 channels. We also map such techniques to widely-adopted security controls, emphasizing gaps or limitations (and success stories) in current best practices.Comment: Work commissioned by CPNI, available at c2report.org. 38 pages. Listing abstract compressed from version appearing in repor
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