A coding approach to the multicast stream authentication problem

We study the multicast stream authentication problem when an opponent can drop, reorder and introduce data packets into the communication channel. In such a model, packet overhead and computing efficiency are two parameters to be taken into account when designing a multicast stream protocol. In this paper, we propose to use two families of erasure codes to deal with this problem, namely, rateless codes and maximum distance separable codes. Our constructions will have the following advantages. First, our packet overhead will be small. Second, the number of signature verifications to be performed at the receiver is O(1). Third, every receiver will be able to recover all the original data packets emitted by the sender despite losses and injection occurred during the transmission of information.

On the security of PAS (predicate-based authentication service)

Recently a new human authentication scheme called PAS (predicate-based authentication service) was proposed, which does not require the assistance of any supplementary device. The main security claim of PAS is to resist passive adversaries who can observe the whole authentication session between the human user and the remote server. In this paper we show that PAS is insecure against both brute force attack and a probabilistic attack. In particular, we show that its security against brute force attack was strongly overestimated. Furthermore, we introduce a probabilistic attack, which can break part of the password even with a very small number of observed authentication sessions. Although the proposed attack cannot completely break the password, it can downgrade the PAS system to a much weaker system similar to common OTP (one-time password) systems.

Beyond online preprints : formalization of open initiatives in China

A growing number of online journals and academic platforms are adopting light peer review or 'publish then filter' models of scholarly communication. These approaches have the advantage of enabling instant exchanges of knowledge between academics and are part of a wider search for alternatives to traditional peer review and certification processes in scholarly publishing. However, establishing credibility and identifying the correct balance between communication and scholarly rigour remains an important challenge for digital communication platforms targeting academic communities. This paper looks at a highly influential, government-backed, open publishing platform in China: Science Paper Online, which is using transparent post-publication peer-review processes to encourage innovation and address systemic problems in China's traditional academic publishing system. There can be little doubt that the Chinese academic publishing landscape differs in important ways from counterparts in the United States and Western Europe. However, this article suggests that developments in China also provide important lessons about the potential of digital technology and government policy to facilitate a large-scale shift towards more open and networked models of scholarly communication.

Online teacher education : lessons from the cyber-trenches

This paper provides an overview of ‘lessons learned’ from the author’s decade long involvement in online teaching and learning, including eight years in the development, implementation, teaching and administration of a wholly online Master of Arts in Applied Linguistics coursework degree program, which attracted several hundred students annually from around the world, and has won awards for innovation, including being identified as a ‘flagship’ program during an external review of the university.

Searching and archiving : exploring online search behaviors of researchers

Searching for relevant peer-reviewed material is an integral part of corporate and academic researchers. Researchers collect huge amount of information over the years and sometimes struggle organizing it. Based on a study with 30 academic researchers, we explore, in combination, different searching and archiving activities of document-based information. Based on our results we provide several implications for design.

Designing and evaluating an online role play in conflict management

Purpose This paper aims to identify, through a literature review, key issues regarding how online role plays can be designed and to apply them when designing a role play on conflict management. Design/methodology/approach By drawing on the key issues identified in the literature review, a role play on conflict management was designed and evaluated. Data were collected by developing a survey that focused on perceived learning, participation and satisfaction. Findings Overall, a majority of the students felt that they learned and participated in the role play. The most positive finding was that the students were satisfied with their role play experience. Research limitations/implications Researchers are urged to further develop the dimensions and measures of online role play success. The measures that were developed for evaluating perceived learning, participation and satisfaction with role plays can be further developed and tested. It is suggested that the effects on learning need to be further explored. Practical implications It is suggested that teachers take the identified key issues of online role play design into account. An important challenge seems to be to encourage students to reflect and do additional reading and research in relation with online role plays. Originality/value Online collaboration is commonly argued as beneficial from an e-learning perspective. However, a challenge for research and practice is to learn how collaborative e-learning activities may be developed. This paper contributes by focusing on how online role plays can be designed and evaluated.

Doing it better? Overseas online retailers aisles ahead

All the signs are there that Australian retailers are not investing enough in their online operations.

Measuring Online user engagement : the limitations of Web analytics

The ability to identify and assess user engagement with transmedia productions is vital to the success of individual projects and the sustainability of this mode of media production as a whole. It is essential that industry players have access to tools and methodologies that offer the most complete and accurate picture of how audiences/users engage with their productions and which assets generate the most valuable returns of investment. Drawing upon research conducted with Hoodlum Entertainment, a Brisbane-based transmedia producer, this chapter outlines an initial assessment of the way engagement tends to be understood, why standard web analytics tools are ill-suited to measuring it, how a customised tool could offer solutions, and why this question of measuring engagement is so vital to the future of transmedia as a sustainable industry.

National and state-level politics on social media : Twitter, Australian political discussions, and the online commentariat

This paper examines the use of Twitter for long-term discussions around Australian politics, at national and state levels, tracking two hashtags during 2012: #auspol, denoting national political topics, and #wapol, which provides a case study of state politics (representing Western Australia). The long-term data collection provides the opportunity to analyse how the Twitter audience responds to Australian politics: which themes attract the most attention and which accounts act as focal points for these discussions. The paper highlights differences in the coverage of state and national politics. For #auspol, a small number of accounts are responsible for the majority of tweets, with politicians invoked but not directly contributing to the discussion. In contrast, #wapol stimulates a much lower level of tweeting. This example also demonstrates that, in addition to citizen accounts, traditional participants within political debate, such as politicians and journalists, are among the active contributors to state-oriented discussions on Twitter.

Challenges of responding to online fraud victimisation in Australia

Online fraud occurs when an individual or a business responds in some manner to an unsolicited invitation received via the internet and suffers financial or other detrimental effects as a result. In 2010–11, the Australian Bureau of Statistics (2012) found that over 1.2 million Australians (6.7% of the population aged 15 years and over) had been a victim of personal fraud, losing approximately $1.4b in the preceding 12 months. More than half of these victims (55.7%) were contacted via the internet or email (online victimisation). In addition to monetary losses, victims of online fraud suffer serious psychological, emotional, social and even physical problems as a consequence of their victimisation. This paper explores the challenges of responding to online fraud victimisation in Australia and describes some of the specific support services that have recently emerged to support victims of this crime.

Social media as online information grounds : a preliminary conceptual framework

Researchers are increasingly grappling with ways of theorizing social media and its use. This review essay proposes that the theory of Information Grounds (IG) may provide a valuable lens for understanding how social media fosters collaboration and social engagement among information professionals. The paper presents literature that helps us understand how social media can be seen as IG, and maps the characteristics of social media to the seven propositions of IG theory. This work is part of a wider study investigating the ways in which Information Technology (IT) professionals experience social media.

Investigating online recognition for blood donor retention : an experiential donor value approach

Recognising that charitable behaviour can be motivated by public recognition and emotional satisfaction, not-for-profit organisations have developed strategies that leverage self-interest over altruism by facilitating individuals to donate conspicuously. Initially developed as novel marketing programs to increase donation income, such conspicuous tokens of recognition are being recognised as important value propositions to nurture donor relationships. Despite this, there is little empirical evidence that identifies when donations can be increased through conspicuous recognition. Furthermore, social media’s growing popularity for self-expression, as well as the increasing use of technology in donor relationship management strategies, makes an examination of virtual conspicuous tokens of recognition in relation to what value donors seek particularly insightful. Therefore, this research examined the impact of experiential donor value and virtual conspicuous tokens of recognition on blood donor intentions. Using online survey data from 186 Australian blood donors, results show that in fact emotional value is a stronger predictor of intentions to donate blood than altruistic value, while social value is the strongest predictor of intentions if provided with recognition. Clear linkages between dimensions of donor value (altruistic, emotional and social) and conspicuous donation behaviour (CDB) were identified. The findings provide valuable insights into the use of conspicuous donation tokens of recognition on social media, and contribute to our understanding into the under-researched areas of donor value and CDB.

Unlocking the "reminder" potential when viewers pause programs : results from a laboratory test of a new online medium

The branded pause advertisement is a recently developed online television-advertising format that displays a full-screen still-image banner ad whenever a viewer pauses a streaming-video program. This study used a controlled lab experiment to compare the effectiveness of branded pause advertisements with normal online television advertisements. The results demonstrate that branded pause advertisements are effective but only when combined with a long-exposure advertisement for the same brand. Despite their short exposure time, pause advertisements function as effective reminders, building awareness through repeat exposure. The findings of the current study were similar regardless of whether pause advertisements were activated as a result of viewers’ pausing at a time of their own choosing or whether viewers were interrupted.