MoCA: A Middleware for Developing Collaborative Applications for Mobile Users

Abstract

MoCA the Mobile Collaboration Architecture is a middleware for developing and deploying context-aware collaborative applications for mobile users. It comprises client and server APIs, core services for monitoring and inferring the mobile devices' context, and an object-oriented framework for instantiating customized application proxies.Portable computing devices with wireless communication interfaces such as PDAs or smart phones are becoming more powerful and commonplace. Consequently, demand has increased for applications and services that support communication and collaboration among mobile users. This new distributed computing environment poses new challenges, such as host mobility, limited device resources, and intermittent connectivity. However, it also opens up a range of different and unexplored forms of collaboration among mobile users, in which, for example, information about user locality and proximity could play a distinguished role in determining an interaction's form and participants.We argue that collaboration in a static network differs significantly from collaboration in a mobile network. While for collaboration based on static networks, one implicitly assumes that all user devices have stable connectivity, this isn't the case in a mobile environment. Because mobile networks suffer from weak and intermittent connectivity, a user might become temporarily unavailable even though he or she is still engaged in the collaboration session. Hence, in a mobile setting, the requirements for synchronous views and mutual perception for the collaborating peers (collaboration awareness) needs to be redefined.Another difference is related to user mobility. When users are mobile, the collaborating group

Seaweed reproductive biology: environmental and genetic controls

“…Additional insights have been provided by transcriptomic analyses in a number of species, including Pyropia (Uji et al 2013) and Gracilariopsis (Kamiya et al 2011), which have identified sets of genes upregulated in different phases of the life cycle. In Gracilaria, Hydropuntia and Grateloupia, research has focused on the ornithine decarboxylase GiODC gene, which regulates carpospore maturation and liberation (Guzmán-Urióstegui et al 2002, Sacramento et al 2004b, García-Jiménez et al 2009, reviewed in García-Jiménez and Robaina 2015. Variation in the expression of GiODC was observed during cystocarp development with levels reduced in fertile tissue (García-Jiménez et al 2009).…”

Discovering services with restricted location scope in ubiquitous environments

“…Besides context management and synchronous querying, CIS also supports context monitoring, allowing clients to register their interest in specific context states (involving one or several context variables) modeled as logical expressions, and to be asynchronously notified whenever the corresponding context-expression is satisfied (or ceases to be satisfied) [5]. For instance, with the expression {"FreeMemory < 10KB" OR "APChange = True"}, an application may subscribe to be notified when the free memory of the device is less than 10KB or when occurs a change of 802.11 network access point.…”

“…MoCA architecture [5] has been designed to support the development and deployment of context-aware applications involving mobile devices, and its core services are also adequate for the development and deployment of ubiquitous applications. MoCA's Location Inference Service (LIS) allows to infere the location (and follow the movements) of 802.11-enabled mobile devices within an organization.…”

A privacy service for location-based collaboration among mobile users

“…This service has been integrated into the MoCA architecture -Mobile Collaboration Architecture [42,31], which allowed us to develop and experiment with some privacy-sensitive and location-aware application prototypes. The main contribution of our work is that we propose a larger, more comprehensible and effective set of privacy control mechanisms that assist the user in building and maintaining her privacy policy.…”