State of Internet Measurement in Africa - A Survey

This paper presents the results of a survey aimed at understanding the status of Internet measurement platforms usage, deployment and capabilities in Africa. It presents findings related to prevalence of measurement in the region, the reasons why the different business categories investigated conduct Internet measurement as well as the metrics of interest to these entities. The survey also looked at the popular measurement platforms that the respondents use in their measurement activities as well as the platforms that are hosted by businesses and users in the African region. The survey also recorded responses related to data handling and privacy considerations. A total of 123 responses were received from 34 countries. The survey revealed that Internet measurements are not widely conducted in the region largely due to the inadequacy of deployed measurement platforms, the lack of awareness in the subject, and the lack of relevant skills to carry out the measurement tasks. We outlined some recommendations to remedy these issues

Deep Diving into Africa’s Inter-Country Latencies

The Internet in Africa is evolving rapidly, yet remains significantly behind other regions in terms of performance and ubiquity of access. This clearly has negative consequences for the residents of Africa, but also has implications for organisations designing future networked technologies that might see deployment in the region. This paper presents a measurement campaign methodology to explore the current state of the African Internet. Using vantage points across the continent, we perform the first large scale mapping of inter-country delays in Africa. Our analysis reveals a number of clusters, where countries have built up low delay interconnectivity, dispelling the myth that intra-communications in Africa are universally poor. Unfortunately, this does not extend to the remainder of the continent, which typically suffers from excessively high delays, often exceeding 300ms. We find that in many cases it is faster to reach European or North American networks that those in other regions of Africa. By mapping the internetwork topology, we identify a number of shortcomings in the infrastructure, most notably an excessive reliance on intercontinental transit providers

The Shortcomings of Globalised Internet Technology in Southern Africa

Network protocols and applications have mostly been devel- oped in and for a Western context and usually have an embedded set of assumptions about network performance and availability. As a result web-browsing, cloud-based services, live voice and video over IP, desktop applications and software updates often fail or perform poorly in (rural) areas of Southern Africa. This paper uncovers some of the reasons for this poor performance such as Windows TCP failing to reach capacity in high-delay networks, long DNS delays or time-outs and applications such as Office365 assuming constant connectivity to function, and de- scribes them, set in the Southern African contexts. We address the issue of colonisation in ICT context and show the extend of such in the area of networking. These observations provide strong motivation for Africa- based engineering research to ensure that future network protocols and applications are context-sensitive, adaptive and truly global

Inside the Walled Garden: Deconstructing Facebook's Free Basics Program

Free Basics is a Facebook initiative to provide zero-rated web services in developing countries. The program has grown rapidly to 60+ countries in the past two years. But it has also seen strong opposition from Internet activists and has been banned in some countries like India. Facebook highlights the societal benefits of providing low-income populations with free Internet access, while detractors point to concerns about privacy and network neutrality. In this paper, we provide the first independent analysis of such claims regarding the Free Basics service, using both the perspective of a Free Basics service provider and of web clients visiting the service via cellular phones providing access to Free Basics in Pakistan and South Africa. Specifically, with control of both endpoints, we not only provide a more detailed view of how the Free Basics service is architected, but also can isolate the likely causes of network performance impairments. Our analysis reveals that Free Basics services experience 4 to 12 times worse network performance than their paid counterparts. We isolate the root causes using factors such as network path inflation and throttling policies by Facebook and telecom service providers. The Free Basics service and its restrictions are designed with assumptions about users' device capabilities (e.g., lack of JavaScript support). To evaluate such assumptions, we infer the types of mobile devices that generated 47K unique visitors to our Free Basics services between Sep 2016 and Jan 2017. We find that there are large numbers of requests from constrained WAP browsers, but also large fractions of high-capability mobile phones that send Free Basics requests. We discuss the implications of our observations, with the hope to aid more informed debates on such telecom policies

Inactivation of pathogens on food and contact surfaces using ozone as a biocidal agent

This study focuses on the inactivation of a range of food borne pathogens using ozone as a biocidal agent. Experiments were carried out using Campylobacter jejuni, E. coli and Salmonella enteritidis in which population size effects and different treatment temperatures were investigate

A New Medium for Remote Music Tuition

It is common to learn to play an orchestral musical instrument through regular one-to-one lessons with an experienced musician as a tutor. Students may work with the same tutor for many years, meeting regularly to receive real-time, iterative feedback on their performance. However, musicians travel regularly to audition, teach and perform and this can sometimes make it difficult to maintain regular contact. In addition, an experienced tutor for a specific instrument or musical style may not be available locally. General instrumental tuition may not be available at all in geographically distributed communities. One solution is to use technology such as videoconference to facilitate a remote lesson; however, this fundamentally changes the teaching interaction. For example, as a result of the change in communication medium, the availability of non-verbal cues and perception of relative spatiality is reduced. We describe a study using video-ethnography, qualitative video analysis and conversation analysis to make a fine-grained examination of student–tutor interaction during five co-present and one video-mediated woodwind lesson. Our findings are used to propose an alternative technological solution – an interactive digital score. Rather than the face-to-face configuration enforced by videoconference, interacting through a shared digital score, augmented by visual representation of the social cues found to be commonly used in co-present lessons, will better support naturalistic student–tutor interaction during the remote lesson experience. Our findings may also be applicable to other fields where knowledge and practice of a physical skill sometimes need to be taught remotely, such as surgery or dentistry

Comparative Study of Spectral Sensitivity, Irradiance Sensitivity, Spatial Resolution and Temporal Resolution in the Visual Systems of Aratus pisonii and Ocypode quadrata

Autrum’s studies (1950, 1958) on terrestrial arthropods first revealed that the visual systems of arthropods reflected their lifestyles and habitats, demonstrating that rapidly moving predatory diurnal species tend to have better temporal resolution than slower moving nocturnal species. In order to test Autrum’s hypothesis that visual adaptions are driven by predator/prey interactions, the visual physiology of a nocturnal fast-moving predatory crab, the Atlantic ghost crab (Ocypode quadrata), and a diurnal herbivorous crab, the mangrove tree crab (Aratus pisonii), was examined and compared. Spectral sensitivity, irradiance sensitivity, and temporal resolution of the crabs were quantified using the electroretinogram (ERG), while the spatial resolution was calculated utilizing morphological methods. Both O. quadrata and A. pisonii had a single dark-adapted spectral sensitivity peak (494 and 499 nm respectively) and chromatic adaptation had no effect on their spectral sensitivity, indicating that both species have monochromatic visual systems. The temporal resolution of O. quadrata was not significantly different from that of A. pisonii, but O. quadrata did possess a significantly greater spatial resolution and irradiance sensitivity. Both species possess an acuity zone in the anterior region of their eyes. The data presented in this study will aid in the current understanding of the correlation between visual physiology and the life history of the animal