Dragonfly is Password Authenticated Key Exchange protocol that uses a shared session key to authenticate parties based on pre-shared secret password. It was claimed that this protocol was secure against off-line dictionary attack, but a new research has proved its vulnerability to off-line dictionary attack and proving step was applied by using "Patched Protocol" which was based on public key validation. Unfortunately, this step caused a raise in the computation cost, which made this protocol less appealing than its competitors. We proposed an alternate enhancement to keep this protocol secure without any extra computation cost that was known as "Enhanced Dragonfly". This solution based on two-pre-shared secret passwords instead of one and the rounds between parties had compressed into two rounds instead of four. We prove that the enhanced-Dragonfly protocol is secure against off-line dictionary attacks by analyzing its security properties using the Scyther tool. A simulation was developed to measure the execution time of the enhanced protocol, which was found to be much less than the execution time of patched Dragonfly. The off-line dictionary attack time is consumed for few days if the dictionary size is 10,000. According to this, the use of the enhanced Dragonfly is more efficient than the patched Dragonfly.

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Abstract-Global Software Development (GSD) is the most recent and major trend in software engineering domain. It provides many benefits but also faces various challenges in control, communication and coordination due to socio-cultural, geographical and temporal distance. Scrum is increasingly being applied in GSD as it supports teamwork between developers and customers. Scrum method offers a distinctive feature to mitigate the effects of socio-cultural and geographical but not temporal distance on coordination in GSD projects. This paper explains how Scrum helps to mitigate the effects of temporal distance which includes increased coordination costs in GSD projects. A web application called (Distributed Scrum Web Application) provides various advantages for Scrum teams. The main advantage of this application is to facilitate communication among distributed team members.

Abstract-Emerging Opportunistic Networks (ON) are under intensive research and development by many academics. However, research efforts on ON only addressed routing protocols as well as data dissemination. Too little attention was given to the applications that can be deployed over ON. These are assumed to use immutable data (e.g., photos/video files). Nevertheless, Collaborative Editors (CE) which are based on mutable messages are widely used in many fields. Indeed, they allow many users to concurrently edit the same shared document (e.g., Google Docs). Consequently, it becomes necessary to adapt CE to ON which represents a challenging task. As a matter of fact, CE synchronization algorithms should ensure the convergence of the shared content being modified concurrently by users. In this work, we give an overview on ON and CE in an attempt to combine both states of the art. We highlight the challenges that could be faced when trying to deploy CE over ON.

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