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- Kanter, Theo, 1954-, et al.
(författare)
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Distributed Context Support for Ubiquitous Mobile Awareness Services
- 2009
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Ingår i: 2009 Fourth International ICST Conference on Communications and Networking in China. ChinaCom'09.. - : IEEE conference proceedings. - 9781424443376 ; , s. 869-873
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Konferensbidrag (refereegranskat)abstract
- Context-aware applications and services require ubiquitous access to context information about the users or sensors such as preferences, spatial & environmental data, available connectivity, and device capabilities. Systems for the brokering or the provisioning of context data via wireless networks do so with centralized servers or by employing protocols that do not scale well with real-time distribution capabilities. In other cases, such as the extending of presence systems, the data models are limited in expressive capabilities and consequently incur unnecessary signaling overhead. This paper presents a distributed protocol, the Distributed Context eXchange Protocol (DCXP), and an architecture for the real-time distribution of context information to ubiquitous mobile services: We present the architecture and its principle operation in a sample ubiquitous mobile awareness service. Preliminary results indicate that our approach scales well for the ubiquitous provision of context data in real-time to clients on the Internet via 3G wireless systems. Performed measurements show that DCXP can reduce the time to process context data with a factor of 20 compared to similar approaches.
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| 2. |
- Wang, Qinghua, 1980-, et al.
(författare)
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A Multi-homing Extension of Wireless Node Implementation in Ns-2
- 2009
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Ingår i: 2009 4th International Conference on Communications and Networking in China, CHINACOM 2009. - : IEEE conference proceedings. - 9781424443376 ; , s. 751-756
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Konferensbidrag (refereegranskat)abstract
- Due to the rapid growth of wireless communication, it is now believed that wireless devices with multiple interface support will highly increase in the near future. In the research community of Network Simulator, there has recently been quite a large interest in extending the current wireless node implementation so as to be able to include more than one radio interface to work simultaneously.We focus our efforts on the extension of multi-homing ability of ns-2, which has been the most used network simulator in wireless network research. Multi-homing here is defined as the ability of a single end-point to support multiple IP addresses by the use of multiple interfaces. The ns-2 simulation environment is a flexible tool for network engineers to investigate how various protocols perform with different configurations and topologies. However, the support for wireless and mobile networking in ns-2 is monolithic and not entirely consistent with basic design principles so that it makes it quite difficult, if not impossible, to extend a multi-homing support based on current mobilenode design. This paper describes how we extend the ns-2 framework to include support for an imititated wireless multi-homed node.
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