<p>This thesis explored how hearing and deaf users are brought together into one communication space where interaction between them is a semi-synchronous form of message exchange. The focus of this thesis was the means by which message delivery between two e</p>

The modern workplace environment is filled with interruptions due to the necessity of coworkers to communicate with each other. Studies have revealed that interruptions can disrupt the ability of a knowledge worker to concentrate on a task, which can impact task performance (TP). Communication interruptions are due, in part, to the unavoidable side-effect of using technology to facilitate these interactions. Human-computer-interaction (HCI) involving instant messaging (IM) communication tools can cause interruptions to occur as coworkers use this technology to communicate on various work related activities. The main goal of this research was to empirically investigate the role of instant messaging interruptions (IMI) on knowledge workers' TP in the workplace. This research used a field experiment to investigate the role of IMI on knowledge worker TP during e-learning-based training. With the pervasive use of computers in the workplace, e-learning training has become an efficient and effective way to deliver training to knowledge workers. The experiment utilized a posttest-only control group design using two experimental groups and one control group. Each group consisted of four e-learning training tasks of varying task complexity (TC). These included simple and complex tasks involving symbolic and spatial manipulation. While working on the e-learning training tasks, the participants in the experimental groups were interrupted by randomly generated IMI. One experimental group experienced a low number of IMI (LIMI) and one experienced a high number of IMI (HIMI). The control group experienced no IMI (NIMI). The volunteer participants were selected at-random from the online administrative department of a local technical college. A total of 60 experiments were conducted and multivariate analysis of covariance (MANCOVA) of the 120 usable records revealed that the time to complete a task (TPtct), for simple and complex, as well as symbolic and spatial tasks were affected by increased IMI. Results for changes to task accuracy (TPacc) were not statistically significant. Implications of this study for research were the identification of gaps in previous research concerning environment of the experiments and the type of interrupting medium that was used. Previous research has been primarily conducted in a laboratory environment with interruptions generated by means other than IM. This research used IM as the interrupting medium with participants working in their normal workplace environment. Implications for practitioners were the additional time required to complete a task when interrupted by IMI and the way in which workers seem to compensate for the distraction.

<p>Vi ville med denna uppsats undersöka om instant messaging matchar de kommunikationsbehov som IT-anställda har. För att ta reda på detta använde vi oss av ett kvalitativt angreppssätt i form av intervjuer. Dessa intervjuer skapade även ytterligare kunskap vilken vi benämnt barriärer. En lista på IM-funktioner hämtades från Wikipedia och reviderades senare av oss. Kommunikationsbehoven identifierades under analysen av intervjuerna. Matchningen genererade en tabell som kan användas som karta över vilka IM-funktioner som tillgodoser några vanliga kommunikationsbehov som finns på datortäta arbetsplatser. Barriärerna är till för att visa vad som försvårar tillgodoseendet av behoven. Vidare erhöll vi även kunskap om att de av oss identifierade kommunikationsbehov som i dagsläget inte tillgodoses av IM inte heller behöver göra det. Vi kom också fram till att IM skulle kunna utvecklas till att vara en brygga mellan annan kommunicerande programvara och kollegor.</p>

Instant Messaging (IM) has grown rapidly among network users. It has even become a very important tool for the industry around the world. It is used in scheduling meetings, exchanging business information and clients information, and so on. Instant Messaging has been developed by private sectors or providers such as America Online Instant Messenger (AIM), MSN, and Yahoo; however, in 1998 a new protocol has seen the light as an open source Instant Messaging protocol and had the name of Jabber and thanks to Jeremie Miller the founder of the Jabber protocol. The project gathered wide public attention when it was discussed on the popular developer discussion website Slashdot in January 1999. In May 2000, the core Jabber protocols were released as open source reference server and it have not been changed to this day. Jabber uses client-server architecture, not a direct peer-to-peer architecture as some other messaging systems do. It is actually an Extensible Markup Language (XML) messaging protocol. It relies on XML document format in every aspect of the communication. [1] Jabber Protocol have gone a long way to be one of the most attractive protocol because of its open source and extensibility. Anyone can build or extend the jabber protocol functionality without actually modifying the core protocol and still maintain interoperability with other IM clients such as Yahoo and MSN. Moreover, as the usage of Jabber Instant Messaging technology increases, the need for information protection in the Jabber messaging medium also increases. This thesis will explore the Jabber protocol and the ability to secure a Jabber based communication over the network using third party cryptographic libraries. / Graduation date: 2003

A recent surge in the usage of instant messaging (IM) applications on mobile devices has brought the energy efficiency of those applications into the light. We are entering an era where IM applications are changing the message communication on mobile devices, beginning to overtake SMS messages and even phone calls in some cases. Smartphones experience a tremendous increase of data transmissions through wireless interfaces. As illustrated in this work, today's IM applications differ vastly in energy consumption when using the third generation (3G) cellular communication. This thesis focuses on studying the 3G transmission energy footprint of IM applications at the handset level. The energy cost of a common feature used in IM applications that informs that the user is currently typing a response ('typing notify'), is evaluated. The feature is shown to incur a great increase in energy cost compared to the base chat function, ranging from an increase of 43 % to 117 %. The work also proposes a bundle technique that aggregates chat messages over time reducing the energy consumption at the cost of delay for the user. The results show that the bundle technique can save up to 47 % in energy consumption while still keeping the chat function. For the evaluation, conversations collected from a popular IM application are used.

Awareness servers provide information about a person to help observers determine whether a person is available for contact. A trade -off exists in these systems: more sources of information, and higher fidelity in those sources, can improve peoples decisions, but each increase in information reduces privacy. In this thesis, we look at whether the type of relationship between the observer and the person being observed can be used to manage this trade-off. We conducted a survey that asked people what amount of information from different sources that they would disclose to seven different relationship types. We found that in more than half of the cases, people would give different amounts of information to different relationships. We then constructed a prototype system and conducted a Wizard of Oz experiment where we took the system into the real world and observed individuals using it. Our results suggest that awareness servers can be improved by allowing finer-grained control than what is currently available.

Faculty of Criminology, Justice and Policy Studies

Awareness servers provide information about a person to help observers determine whether a person is available for contact. A trade -off exists in these systems: more sources of information, and higher fidelity in those sources, can improve peoples decisions, but each increase in information reduces privacy. In this thesis, we look at whether the type of relationship between the observer and the person being observed can be used to manage this trade-off. We conducted a survey that asked people what amount of information from different sources that they would disclose to seven different relationship types. We found that in more than half of the cases, people would give different amounts of information to different relationships. We then constructed a prototype system and conducted a Wizard of Oz experiment where we took the system into the real world and observed individuals using it. Our results suggest that awareness servers can be improved by allowing finer-grained control than what is currently available.

Instant messaging (IM) has been a platform of spreading malware for hackers due to its popularity and immediacy. To evade anti-virus detection, hacker might send malicious URL message, instead of malicious binary file. A malicious URL is a link pointing to a malware file or a phishing site, and it may then propagate through the victim's contact list. Moreover, hacker sometimes might use social engineering tricks making malicious URLs hard to be identified. The previous solutions are improper to detect IM malicious URL in real-time. Therefore, we propose a novel approach for detecting IM malicious URL in a timely manner based on the anomalies of URL messages and sender's behavior. Malicious behaviors are profiled as a set of behavior patterns and a scoring model is developed to evaluate the significance of each anomaly. To speed up the detection, the malicious behavior patterns can identify known malicious URLs efficiently, while the scoring model is used to detect unknown malicious URLs. Our experimental results show that the proposed approach achieves low false positive rate and low false negative rate.

Thesis (M.A.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 64-66).