An overview of Fog computing and its security issues

Fog computing is a paradigm that extends Cloud computing and services to the edge of the network. Similar to Cloud, Fog provides data, compute, storage and application services to end users. In this article, we elaborate the motivation and advantages of Fog computing and analyse its applications in a series of real scenarios, such as Smart Grid, smart traffic lights in vehicular networks and software defined networks. We discuss the state of the art of Fog computing and similar work under the same umbrella. Distinguished from other reviewing work of Fog computing, this paper further discloses the security and privacy issues according to current Fog computing paradigm. As an example, we study a typical attack, man-in-the-middle attack, for the discussion of system security in Fog computing. We investigate the stealthy features of this attack by examining its CPU and memory consumption on Fog device. In addition, we discuss the authentication and authorization techniques that can be used in Fog computing. An example of authentication techniques is introduced to address the security scenario where the connection between Fog and Cloud is fragile.

Frontier technologies of trust computing and network security

The increasing complexity of computer systems and communication networks induces tremendous requirements for trust and security. This special issue includes topics on trusted computing, risk and reputation management, network security and survivable computer systems/networks. These issues have evolved into an active and important area of research and development. The past decade has witnessed a proliferation of concurrency and computation systems for practice of highly trust, security and privacy, which has become a key subject in determining future research and development activities in many academic and industrial branches. This special issue aims to present and discuss advances of current research and development in all aspects of trusted computing and network security. In addition, this special issue provides snapshots of contemporary academia work in the field of network trusted computing. We prepared and organized this special issue to record state-of-the-art research, novel development and trends for future insight in this domain. In this special issue, 14 papers have been accepted for publication, which demonstrate novel and original work in this field. A detailed overview of the selected works is given below.

Economic evaluation of price discounts and skill-building strategies on purchase and consumption of healthy food and beverages: The SHELf randomized controlled trial

OBJECTIVE: Pricing strategies are a promising approach for promoting healthier dietary choices. However, robust evidence of the cost-effectiveness of pricing manipulations on dietary behaviour is limited. We aimed to assess the cost-effectiveness of a 20% price reduction on fruits and vegetables and a combined skills-based behaviour change and price reduction intervention. DESIGN AND METHODS: Cost-effectiveness analysis from a societal perspective was undertaken for the randomized controlled trial Supermarket Healthy Eating for Life (SHELf). Female shoppers in Melbourne, Australia were randomized to: (1) skill-building (n = 160); (2) price reductions (n = 161); (3) combined skill-building and price reduction (n = 161); or (4) control group (n = 161). The intervention was implemented for three months followed by a six month follow-up. Costs were measured in 2012 Australian dollars. Fruit and vegetable purchasing and consumption were measured in grams/week. RESULTS: At three months, compared to control participants, price reduction participants increased vegetable purchases by 233 g/week (95% CI 4 to 462, p = 0.046) and fruit purchases by 364 g/week (95% CI 95 to 633, p = 0.008). Participants in the combined group purchased 280 g/week more fruits (95% CI 27 to 533, p = 0.03) than participants in the control group. Increases were not maintained six-month post intervention. No effect was noticed in the skill-building group. Compared to the control group, the price reduction intervention cost an additional A$2.3 per increased serving of vegetables purchased per week or an additional A$3 per increased serving of fruit purchased per week. The combined intervention cost an additional A$12 per increased serving of fruit purchased per week compared to the control group. CONCLUSIONS: A 20% discount on fruits and vegetables was effective in promoting overall fruit and vegetable purchases during the period the discount was active and may be cost-effective. The price discount program gave better value for money than the combined price reduction and skill-building intervention. The SHELf trial is registered with Current Controlled Trials Registration ISRCTN39432901.

The comparative cost of food and beverages at remote Indigenous communities, Northern Territory, Australia

OBJECTIVE: To determine the average price difference between foods and beverages in remote Indigenous community stores and capital city supermarkets and explore differences across products.

METHODS: A cross-sectional survey compared prices derived from point-of-sale data in 20 remote Northern Territory stores with supermarkets in capital cities of the Northern Territory and South Australia for groceries commonly purchased in remote stores. Average price differences for products, supply categories and food groups were examined.

RESULTS: The 443 products examined represented 63% of food and beverage expenditure in remote stores. Remote products were, on average, 60% and 68% more expensive than advertised prices for Darwin and Adelaide supermarkets, respectively. The average price difference for fresh products was half that of packaged groceries for Darwin supermarkets and more than 50% for food groups that contributed most to purchasing.

CONCLUSIONS: Strategies employed by manufacturers and supermarkets, such as promotional pricing, and supermarkets' generic products lead to lower prices. These opportunities are not equally available to remote customers and are a major driver of price disparity.

IMPLICATIONS: Food affordability for already disadvantaged residents of remote communities could be improved by policies targeted at manufacturers, wholesalers and/or major supermarket chains.

Food and passion: technologies of self transformation in Jamie’s kitchen

Since the 1990s there has been a surge of televisual dramatisations of real-life cooking shows in industrialised countries (Versteegan 2010: 447). Through reality television cooking shows such as, MasterChef, Jamie 's Kitchen, Hell's Kitchen, viewers have encountered celebrity chefs, 'foodies', hospitality trainees, contestants, cooking competitions and customers. These shows have been understood as an indication of- and intervention into - contemporary consumption trends and as vehicles for social change. Many reality-based cooking shows have been regarded as educational, pedagogical sites that 'encourage populations to undertake surveillance of their own and others' bodies' and eating habits with messages like: 'You are what you eat!' or 'Organic is better' (Rich 2011: 3; see also Lewis 2007 and Chapter 4 in this book by Szkupinski-Quiroga, Sandlin and Redmon Wright).In this chapter we explore the reality television programme Jamie's Kitchen as a pedagogical site which seeks to transform young people's understandings about food, work and ultimately themselves. In 2002 the high-profile celebrity chef Jamie Oliver set out to transform a group of unemployed young Londoners into the enterprising, ideal workers of twenty-first century, :flexible capitalism.1 This process of transformation was represented in the enormously successful Channel 4 TV series Jamie's Kitchen.2 In Australia, we viewed the series, as it was screened on Channel 10 over five weeks during July and August 2003.

Designing a healthy food partnership: lessons from the Australian food and health dialogue

BACKGROUND: Poor diets are a leading cause of disease burden worldwide. In Australia, the Federal Government established the Food and Health Dialogue (the Dialogue) in 2009 to address this issue, primarily through food reformulation. We evaluated the Dialogue's performance over its 6 years of operation and used these findings to develop recommendations for the success of the new Healthy Food Partnership.

METHODS: We used information from the Dialogue website, media releases, communiqués, e-newsletters, materials released under freedom-of-information, and Parliamentary Hansard to evaluate the Dialogue's achievements from October 2013 to November 2015, using the RE-AIM (reach, efficacy, adoption, implementation and maintenance) framework. We also engaged closely with two former Dialogue members. Our findings update a prior assessment done in October 2013.

RESULTS: Little data is available to evaluate the Dialogue's recent achievements, with no information about progress against milestones released since October 2013. In the last 2 years, only one additional set of sodium reduction targets (cheese) was agreed and Quick Service Restaurant foods were added as an area for action. Some activity was identified in 12 of a possible 137 (9 %) areas of action within the Dialogue's mandate. Independent evaluation found targets were partially achieved in some food categories, with substantial variation in success between companies. No effects on the knowledge, behaviours or nutrient intake of the Australian population or evidence of impact on diet-related disease could be identified.

CONCLUSIONS: The new Healthy Food Partnership has similar goals to the Dialogue. While highly laudable and recognised globally as cost-effective, the mechanism for delivery in Australia has been woefully inadequate. Strong government leadership, adequate funding, clear targets and timelines, management of conflict of interest, comprehensive monitoring and evaluation, and a plan for responsive regulation in the event of missed milestones will be required if the new Healthy Food Partnership is to achieve its urgent public health goals.

Progress achieved in restricting the marketing of high-fat, sugary and salty food and beverage products to children

In May 2010, 192 Member States endorsed Resolution WHA63.14 to restrict the marketing of food and non-alcoholic beverage products high in saturated fats, trans fatty acids, free sugars and/or salt to children and adolescents globally. We examined the actions taken between 2010 and early 2016 - by civil society groups, the World Health Organization (WHO) and its regional offices, other United Nations (UN) organizations, philanthropic institutions and transnational industries - to help decrease the prevalence of obesity and diet-related noncommunicable diseases among young people. By providing relevant technical and policy guidance and tools to Member States, WHO and other UN organizations have helped protect young people from the marketing of branded food and beverage products that are high in fat, sugar and/or salt. The progress achieved by the other actors we investigated appears variable and generally less robust. We suggest that the progress being made towards the full implementation of Resolution WHA63.14 would be accelerated by further restrictions on the marketing of unhealthy food and beverage products and by investing in the promotion of nutrient-dense products. This should help young people meet government-recommended dietary targets. Any effective strategies and actions should align with the goal of WHO to reduce premature mortality from noncommunicable diseases by 25% by 2025 and the aim of the UN to ensure healthy lives for all by 2030.

Are information sources associated with Australian`s beliefs about the necessity of meat?

The aim of this study was to examine whether use of and trust in health, food, and nutrition information sources are associated with the belief that meat is a necessary dietary component. Over 700 South Australians participated in a questionnaire survey that included questions on frequency of use of and level of trust in information sources, vegetarian status, meat beliefs, and demography. It was found that information sources are associated with the belief that meat is necessary, since they
accounted for over 40% of the variance for all respondents. The most important associations were: lack of use of unorthodox sources; trust in orthodox sources; trust in advertising and the mass media; and trust in and use of social sources. There were differences in which predictors were important, however, depending on the respondent's sex, age, and vegetarian status. The implications of these observed communities of interest for health promotion are discussed.

Children's healthful eating : from research to practice

This paper provides a brief overview of some of the challenges facing the world community in promoting the nutrition status of schoolchildren. It begins by describing the main objectives and aims of children's nutrition promotion and then moves to consider the needs and environments of schoolchildren, the purposes of education and food and nutrition promotion, and the domains of schools and teachers. In the second part of the paper the evidence bases for food and nutrition promotion are considered, especially the gaps in current knowledge. This leads to a discussion of useful practice models as well as a case study of a school health promotion program in Australia. The final part of the paper examines some proposals for schoolchildren's food and nutrition policies, which might be implemented in local schools as well as nationally and internationally. The main theme underlying these proposals is that policies must be created and their effectiveness monitored regularly and reported back to schoolteachers, health workers, school communities, and governments.

Simplified or erroneous? It’s a fine line

Novice learners need to have simplified explanations because they are unable to understand fuller, more-involved explanations. However, there is a dangerously thin line between simplified explanations and over-simplified erroneous explanations, which lead to later misunderstandings and misconceptions. It is harder to unlearn misunderstandings and misconceptions, than to learn something new ab initio.

It is virtually impossible for any teacher to know everything that students will need for future study and careers, as each subject will lead to a myriad of pathways. For example, in my undergraduate 1st year class, students will go into numerous majors across more than 16 degree programs ranging from arts to zoology and from engineering to food-and-nutrition. 

Sociodemographic factors associated with healthy eating and food security in socio-economically disadvantaged groups in the UK and Victoria, Australia

Objective
To investigate the associations between sociodemographic factors and both diet indicators and food security among socio-economically disadvantaged populations in two different (national) contextual settings.

Design
Logistic regression was used to determine cross-sectional associations between nationality, marital status, presence of children in the household, education, employment status and household income (four low income categories) with daily fruit and vegetable consumption, low-fat milk consumption and food security.

Setting
Socio-economically disadvantaged neighbourhoods in the UK and Australia.

Subjects
Two samples of low-income women from disadvantaged neighbourhoods: (i) in the UK, the 2003–05 Low Income Diet and Nutrition Survey (LIDNS; n 643); and (ii) in Australia, the 2007–08 Resilience for Eating and Activity Despite Inequality (READI; n 1340).

Results
The influence of nationality, marital status and children in the household on the dietary outcomes varied between the two nations. Obtaining greater education qualifications was the most telling factor associated with healthier dietary behaviours. Being employed was positively associated with low-fat milk consumption in both nations and with fruit consumption in the UK, while income was not associated with dietary behaviours in either nation. In Australia, the likelihood of being food secure was higher among those who were born outside Australia, married, employed or had a greater income, while higher income was the only significant factor in the UK.

Conclusions
The identification of factors that differently influence dietary behaviours and food security in socio-economically disadvantaged populations in the UK and Australia suggests continued efforts need to be made to ensure that interventions and policy responses are informed by the best available local evidence.

Nutrition knowledge and food consumption: can nutrition knowledge change food behaviour?

The status and explanatory role of nutrition knowledge is uncertain in public health nutrition. Much of the uncertainty about this area has been generated by conceptual confusion about the nature of knowledge and behaviours, and, nutrition knowledge and food behaviours in particular. So the paper  describes several key concepts in some detail. The main argument is that 'nutrition knowledge' is a necessary but not sufficient factor for changes in consumers' food behaviours. Several classes of food behaviours and their causation are discussed. They are influenced by a number of environmental and intra-individual factors, including motivations. The interplay between motivational factors and information processing is important for nutrition promoters as is the distinction between declarative and procedural  knowledge. Consideration of the domains of nutrition knowledge shows that their utility is likely to be related to consumers' and nutritionists' particular goals and viewpoints. A brief survey of the recent literature shows that the evidence for the influence of nutrition knowledge on food behaviours is mixed. Nevertheless, recent work suggests that nutrition knowledge may play a small but pivotal role in the adoption of healthier food habits. The implications of this overview for public health nutrition are: (i) We need to pay greater attention to the development of children's and adults' knowledge frameworks (schema building); (ii) There is a need for a renewed proactive role for the education sector; (iii) We need to take account of consumers' personal food goals and their acquisition of procedural knowledge which will enable them to attain their goals; (iv) Finally, much more research into the ways people learn and use food-related knowledge is required in the form of experimental interventions and longitudinal studies.