BUKU ABSTRAK - Universiti Putra Malaysia

Science, Technology & Engineering
Authorised Control Frame Model to Prevent Virtual Carrier Sense DoS Attacks in
IEEE 802.11 Wireless Networks
Assoc. Prof. Dr. Abdul Azim Abd. Ghani
Mina Malekzadeh, Shamala Subramaniam and Jalil Desa
Faculty of Computer Science and Information Technology, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8946 6555; azim@fsktm.upm.edu.my
IEEE 802.11 standard provides several security protocols to make secure data frames through
communications. However protection offered by these protocols applies only on data frames and control frames
are left without any security. Wireless control frames including RTS, CTS, ACK, CF-End, and CF-End-ACK
frames have a duration field which represents the amount of time that the wireless channels is kept busy by
the sender. During this time, all wireless stations except the senders must keep silent and they cannot transmit
anything. An attacker exploits this vulnerability and continually transmits forgery control frames with the highest
possible value for duration field (32767us) to disrupt normal communication between network stations. The
main purpose of the attacker is to cause a complete loss of availability and prevent legitimate use of provided
resources for authorised users in the target wireless network. These types of attacks while severely can block the
entire wireless network performance, are easy to perform against wireless networks. Wireless networks have very
limited resources such as bandwidth, buffer, computation power, and battery lifetime. Thus they are extremely
susceptible to DoS attacks which focus on resource exhaustion. Wireless DoS attacks do not need a very highpowered
radio frequency interface therefore physically locating the attacker is very difficult. In this work, first
we provide a real testbed to conduct DoS attacks in wireless network. The testbed results prove how the attacks
can easily shutdown the target wireless networks. Then two distinct models are proposed and developed through
simulations as countermeasure to prevent DoS attacks over the wireless networks. The performance measures
are collected through several experiments which are used to compare performance of the models with each other
and with the current model as well. The results prove that the models are completely successful to prevent DoS
attacks against 802.11 wireless networks
Keywords: Wireless network security, HMAC-SHA1, HMAC-SHA2
Coalescence of XML-based Really Simple Syndycator (RSS)
Assoc. Prof. Dr. Abdul Azim Abd. Ghani
Teh Phoey Lee, Hamidah Ibrahim and Rodziah Atan
Faculty of Computer Science and Information Technology, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8946 6555; azim@fsktm.upm.edu.my
Really Simple Syndication aggregator has been widely applied onto several applications such as news
headlines, poscasting, education, medical, geospatial and weblogs. The purpose of RSS is to enable users
aggregating new content updates on the favourite site which has subscribed to the RSS feeder instead of visiting
the sites individually. Blogging over the internet has become a hobby amongst the internet veteran, whether they
are politicians, retired teachers, students, lawyers, journalist etc. The usage of RSS aggregator as a tool onto the
blogging environment has become the latest form of internet phenomenon. Weblogs written in chronological
order will discuss several different topics, while RSS serves as a tool to aggregate new content updates on the
site subscribed. However, each of the independent readers have their different interests in several aspects, such as
cooking, computing, football, scholarly literature, political issues and etc. Relevant topics that have been raised
by multiple writers from different sites aggregated onto current automated RSS aggregator do not completely
satisfy the readers to find relevant topics from multiple websites. This project involves studying the different
formats used in aggregator with aggregated result in terms of the coalescence of their metadata. The project also
covers the issues of ambiguity of the weblogs on the relevant topics aggregated by the user based on user interest.
PheRSS is proposed to help in resolving these problems hybriding the technique on the selected topics.
Keywords: RSS, weblogs, tag, folksonomy, keyword index indicator
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