A review of current DNS TTL practices
- Authors: Van Zyl, Ignus , Rudman, Lauren , Irwin, Barry V W
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427813 , vital:72464 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622760_A_review_of_current_DNS_TTL_practices/links/5b9a16e292851c4ba8181b7f/A-review-of-current-DNS-TTL-practices.pdf
- Description: This paper provides insight into legitimate DNS domain Time to Live (TTL) activity captured over two live caching servers from the period January to June 2014. DNS TTL practices are identified and compared between frequently queried domains, with respect to the caching servers. A breakdown of TTL practices by Resource Record type is also given, as well as an analysis on the TTL choices of the most frequent Top Level Domains. An analysis of anomalous TTL values with respect to the gathered data is also presented.
- Full Text:
- Date Issued: 2015
An investigation into the signals leakage from a smartcard based on different runtime code
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427845 , vital:72466 , https://www.researchgate.net/profile/Ibraheem-Fries-laar/publication/307918229_An_investigation_into_the_signals_leakage_from_a_smartcard_based_on_different_runtime_code/links/57d1996008ae0c0081e04fd5/An-investigation-into-the-signals-leakage-from-a-smartcard-based-on-different-runtime-code.pdf
- Description: This paper investigates the power leakage of a smartcard. It is intended to answer two vital questions: what information is leaked out when different characters are used as output; and does the length of the output affect the amount of the information leaked. The investigation determines that as the length of the output is increased more bus lines are switched from a precharge state to a high state. This is related to the output array in the code increasing its length. Furthermore, this work shows that the output for different characters generates a different pattern. This is due to the fact that various characters needs different amount of bytes to be executed since they have different binary value. Additionally, the information leaked out can be directly linked to the smartcard’s interpreter.
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- Date Issued: 2015
Characterization and analysis of NTP amplification based DDoS attacks
- Authors: Rudman, Lauren , Irwin, Barry V W
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429285 , vital:72573 , 10.1109/ISSA.2015.7335069
- Description: Network Time Protocol based DDoS attacks saw a lot of popularity throughout 2014. This paper shows the characterization and analysis of two large datasets containing packets from NTP based DDoS attacks captured in South Africa. Using a series of Python based tools, the dataset is analysed according to specific parts of the packet headers. These include the source IP address and Time-to-live (TTL) values. The analysis found the top source addresses and looked at the TTL values observed for each address. These TTL values can be used to calculate the probable operating system or DDoS attack tool used by an attacker. We found that each TTL value seen for an address can indicate the number of hosts attacking the address or indicate minor routing changes. The Time-to-Live values, as a whole, are then analysed to find the total number used throughout each attack. The most frequent TTL values are then found and show that the migratory of them indicate the attackers are using an initial TTL of 255. This value can indicate the use of a certain DDoS tool that creates packets with that exact initial TTL. The TTL values are then put into groups that can show the number of IP addresses a group of hosts are targeting.
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- Date Issued: 2015
Data Centre vulnerabilities physical, logical and trusted entity security
- Authors: Swart, Ignus , Grobler, Marthie , Irwin, Barry V W
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427859 , vital:72467 , https://www.researchgate.net/profile/Ignus-Swart/publication/305442546_Data_Centre_vulnerabilities_physical_logical_trusted_entity_security/links/578f38c108aecbca4cada6bf/Data-Centre-vulnerabilities-physical-logical-trusted-entity-security.pdf
- Description: Data centres are often the hub for a significant number of disparate interconnecting systems. With rapid advances in virtualization, the use of data centres have increased significantly and are set to continue growing. Systems hosted typically serve the data needs for a growing number of organizations ranging from private individuals to mammoth governmental departments. Due to this centralized method of operation, data centres have become a prime target for attackers. These attackers are not only after the data contained in the data centre but often the physical infrastructure the systems run on is the target of attack. Down time resulting from such an attack can affect a wide range of entities and can have severe financial implications for the owners of the data centre. To limit liability strict adherence to standards are prescribed. Technology however develops at a far faster pace than standards and our ability to accurately measure information security has significant hidden caveats. This allows for a situation where the defenders dilemma is exacerbated by information overload, a significant increase in attack surface and reporting tools that show only limited views. This paper investigates the logical and physical security components of a data centre and introduces the notion of third party involvement as an increase in attack surface due to the manner in which data centres typically operate.
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- Date Issued: 2015
Design and Fabrication of a Low Cost Traffic Manipulation Hardware Platform
- Authors: Pennefather, Sean , Irwin, Barry V W
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427873 , vital:72468 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622941_Design_and_Fabrication_of_a_Low_Cost_Traffic_Manipulation_Hardware/links/5b9a1625458515310583fc8c/Design-and-Fabrication-of-a-Low-Cost-Traffic-Manipulation-Hardware.pdf
- Description: This paper describes the design and fabrication of a dedicated hardware platform for network traffic logging and modification at a production cost of under $300. The context of the device is briefly discussed before characteristics relating to hardware development are explored. The paper concludes with three application examples to show some to the potential functionality of the platform. Testing of the device shows an average TCP throughput of 84.44 MiB/s when using the designed Ethernet modules.
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- Date Issued: 2015
Facile synthesis and biological evaluation of assorted indolyl-3-amides and esters from a single, stable carbonyl nitrile intermediate
- Authors: Veale, Clinton G L , Edkins, Adrienne L , de la Mare, Jo-Anne , de Kock, Carmen , Smith, Peter J , Khanye, Setshaba D
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66221 , vital:28919 , https://doi.org/10.1016/j.tetlet.2015.02.090
- Description: publisher version , The synthesis of biologically relevant amides and esters is routinely conducted under complex reaction conditions or requires the use of additional catalysts in order to generate sensitive electrophilic species for attack by a nucleophile. Here we present the synthesis of different indolic esters and amides from indolyl-3-carbonyl nitrile, without the requirement of anhydrous reaction conditions or catalysts. Additionally, we screened these compounds for potential in vitro antimalarial and anticancer activity, revealing 1H-indolyl-3-carboxylic acid 3-(indolyl-3-carboxamide)aminobenzyl ester to have moderate activity against both lines.
- Full Text: false
- Date Issued: 2015
FPGA Based Implementation of a High Performance Scalable NetFlow Filter
- Authors: Herbert, Alan , Irwin, Barry V W , Otten, D F , Balmahoon, M R
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427887 , vital:72470 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622948_FPGA_Based_Implementation_of_a_High_Perfor-mance_Scalable_NetFlow_Filter/links/5b9a17a192851c4ba8181ba5/FPGA-Based-Implementation-of-a-High-Performance-Scalable-NetFlow-Filter.pdf
- Description: Full packet analysis on firewalls and intrusion detection, although effec-tive, has been found in recent times to be detrimental to the overall per-formance of networks that receive large volumes of throughput. For this reason partial packet analysis algorithms such as the NetFlow protocol have emerged to better mitigate these bottlenecks. This research delves into implementing a hardware accelerated, scalable, high per-formance system for NetFlow analysis and attack mitigation. Further-more, this implementation takes on attack mitigation through collection and processing of network flows produced at the source, rather than at the site of incident. This research platform manages to scale out its back-end through dis-tributed analysis over multiple hosts using the ZeroMQ toolset. Fur-thermore, ZeroMQ allows for multiple NetFlow data publishers, so that plug-ins can subscribe to the publishers that contain the relevant data to further increase the overall performance of the system. The dedicat-ed custom hardware optimizes the received network flows through cleaning, summarization and re-ordering into an easy to pass form when given to the sequential component of the system; this being the back-end.
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- Date Issued: 2015
How general-purpose can a GPU be?
- Authors: Machanick, Philip
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61180 , vital:27988 , http://dx.doi.org/10.18489/sacj.v0i57.347
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple datastream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions. Supercomputers covered a range of exotic designs such as hypercubes and the Connection Machine (Fox, 1989). The latter is likely the source of the snide comment by Cray: it had thousands of relatively low-speed CPUs (Tucker & Robertson, 1988). Since Cray won, why are we not basing our ideas on his designs (Cray Inc., 2004), rather than those of the losers? The Top 500 supercomputer list is dominated by general-purpose CPUs, and nothing like the Connection Machine that headed the list in 1993 still exists.
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- Date Issued: 2015
How General-Purpose can a GPU be?
- Authors: Machanick, Philip
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439294 , vital:73563 , https://hdl.handle.net/10520/EJC181693
- Description: The use of graphics processing units (GPUs) in general-purpose computation (GPGPU) is a growing field. GPU instruction sets, while implementing a graphics pipeline, draw from a range of single instruction multiple data stream (SIMD) architectures characteristic of the heyday of supercomputers. Yet only one of these SIMD instruction sets has been of application on a wide enough range of problems to survive the era when the full range of supercomputer design variants was being explored: vector instructions.
- Full Text:
- Date Issued: 2015
Human myiasis in rural South Africa is under-reported
- Authors: Kuria, Simon K , Villet, Martin H , Kingu, H J C , Dhaffala, Adupa
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442425 , vital:73983 , https://www.ajol.info/index.php/samj/article/view/114028
- Description: Background. Myiasis is the infestation of live tissue of humans and other vertebrates by larvae of flies. Worldwide, myiasis of humans is seldom reported, although the trend is gradually changing in some countries. Reports of human myiasis in Africa are few. Several cases of myiasis were recently seen at the Mthatha Hospital Complex, Mthatha, Eastern Cape Province, South Africa (SA).
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- Date Issued: 2015
Influence of mouth status on population structure of southern African endemic estuarine-spawning ichthyofauna in a temperate, temporarily open/closed estuary
- Authors: Tweddle, Gavin P , Froneman, P William
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68071 , vital:29195 , https://doi.org/10.2989/16085914.2015.1051940
- Description: Publisher version , The effect of mouth status on the population structure of three endemic estuarine-spawning fish species was assessed using seine nets from November 2005 to October 2007 in the temporarily open/closed Mpekweni Estuary, Eastern Cape, South Africa. Collectively, these three species accounted for more than 60% of the total fish abundance within the estuary. Monthly length frequency data were analysed. Two species, Gilchristella aestuaria and Glossogobius callidus, displayed normally distributed populations throughout, with recruitment/abundance peaks between spring and autumn, and were unaffected by open mouth and extended marine connection conditions. Atherina breviceps, however, displayed multiple modal peaks in its combined population distribution, suggesting a greater influence of mouth condition on its population structure. Retrospective analyses of the various cohorts for A. breviceps identified peaks in recruitment/abundance during summer, coinciding with open-mouth conditions and, to a lesser extent, with overwash events. This study highlights the importance of mouth phase, not only on the recruitment and population distribution of marine-spawning species, but also on estuarine-spawning fish in temporarily open/closed estuaries along the South African coastline.
- Full Text: false
- Date Issued: 2015
Making media theory from the South:
- Authors: Garman, Anthea
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158873 , vital:40236 , https://doi.org/10.1080/23743670.2015.1008186
- Description: Like many other academics who have joined the digital age I have pages and uploads on Academia.edu, Researchgate, LinkedIn and a Google Scholar-aggregated thing (that seemed to trawl the net for my papers, do it for me and then invite me to view my own collection!). So, I get lots of email alerts telling me when someone has looked at my work and downloaded my papers. I appreciate this virtual community and enjoy participating in it, but the aspect of this that perplexes me is the need to ‘endorse’’ someone for their skills – a practice that seems to stem from LinkedIn’s businessmindedness aimed at youngsters trying to find a foothold on the career ladder. I don’t do endorsements unless the programme forces me to go through this step in order to do what I want to do on the site.
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- Date Issued: 2015
Shifting the priority from giving voice to listening: journalism new
- Authors: Garman, Anthea , Malila, Vanessa
- Date: 2015
- Language: English
- Type: text , article
- Identifier: vital:38355 , http://hdl.handle.net/10520/EJC175773
- Description: If, as the critics have argued, the South African media prioritise the voices of elite, middleclass South Africans, then the majority of South Africans are certainly invisible in the mainstream media. Kate Lacey argues that "listening is at the heart of what it means to be in the world, to be active, to be political" (2013: 163), and as such more than just providing a 'voice' for citizens, the media needs to be engaged in active listening to allow audiences to feel 'heard'. Servaes and Malikhao argue that people are 'voiceless' not because they have nothing to say, but because "nobody cares to listen to them" (2005: 91).
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- Date Issued: 2015
Subjective well-being in Africa
- Authors: Botha, Ferdi , Snowball, Jeanette D
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61084 , vital:27946
- Description: Research on quality of life and subjective well-being (SWB) has witnessed a remarkable growth over the past four decades or so. Since Easterlin’s (1974) seminal contribution on the relationship between happiness and income, thousands of studies have followed that examine the intricacies of subjective well-being (for reviews, see Frey and Stutzer, 2002; Dolan et al., 2008; MacKerron, 2012). These studies have uncovered some very important aspects of individual well-being and have pointed to the fact that money or income is not always (as is often assumed) the most important determinant of SWB.
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- Date Issued: 2015
The effects of tissue type and body size on δ13C and δ15N values in parrotfish (Labridae) from Zanzibar, Tanzania
- Authors: Plass-Johnson, Jeremiah G , McQuaid, Christopher D , Hill, Jaclyn M
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444638 , vital:74256 , https://doi.org/10.1111/jai.12746
- Description: Differences between the stable isotopic ratios (δ13C and δ15N) of two tissues (blood and muscle) from four species of East African coral reef parrotfishes (family: Labridae, tribe: Scarini) were analysed across a broad spectrum of body sizes. Comparison of isotopic ratios between the tissues allowed the assessment of using blood as an alternative tissue to muscle. In 2010–2011, constant differences between tissues (δblood minus δmuscle) were found across a broad range of sampled fish lengths. Linear relationships between the tissues, specific for an isotope, indicate that constants could be generated for converting blood isotope into muscle isotope values. Only one species, Chlorurus sordidus, displayed an inconsistent difference between tissues in δ15N, indicating that this ratio was dependent on fish length. The δ13C of both tissues was positively related linearly to fish length for three species, while δ15N showed no relationship with body length. The results are interpreted as indicating dietary consistency over days to weeks, the time of tissue turnover for blood and muscle, respectively. Lastly, differences among the species, even closely related species, show that the generation of tissue conversion constants is species‐specific.
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- Date Issued: 2015
The law of divorce and dissolution of life partnerships in South Africa: book review
- Authors: Kruuse, Helen
- Date: 2015
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54129 , vital:26394 , http://scholar.ufs.ac.za:8080/xmlui/handle/11660/2454
- Description: Jackie Heaton’s latest contribution to the family law domain is formidable – 777 pages of carefully crafted opinions and discussions of the law affecting divorce and dissolution of life partnerships. Given the range, diversity and depth of issues in this area, it is no wonder that she calls on those being among the best in their field to assist her in writing up the book.
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- Date Issued: 2015