tailieunhanh - Ebook Mobile AD hoc networking (2nd edition): Part 2

(BQ) Part 2 book "Mobile AD hoc networking" has contents: Data dissemination in opportunistic networks, task farming in crowd computing, mobility models, topology, and simulations in VANET, experimental work on VANET,.and other contents. | 12 DATA DISSEMINATION IN OPPORTUNISTIC NETWORKS Chiara Boldrini and Andrea Passarella ABSTRACT Among the alternatives to pure general-purpose MANETs, one of the most promising approach is that of opportunistic networks [2]. Differently from MANETs, opportunistic networks are designed to work properly even when the nodes of the network move. More specifically, opportunistic networks reverse the approach of MANETs, and what was before an accident to avoid (the mobility of nodes) now becomes an opportunity for communications. In fact, in an opportunistic network messages are exchanged between nodes when they come into contact, creating a multi-hop path from the source to the destination of the message. One of the most appealing applications to build upon an opportunistic network is data dissemination. Conceptually, data dissemination systems can be seen as variations of the publish/subscribe paradigm: publisher nodes generate content items and inject them into the network, subscriber nodes declare their interest in receiving certain types of content (., sport news, radio podcast, blog entries, etc.) and strive to get it in some ways. Nodes can usually be publishers and subscribers at the same time. The main difference between message forwarding and content dissemination is that the source and destination of a message are typically well known when routing a message (and clearly listed in the header of the message itself), while, in content dissemination, content generators and content consumers might well be unaware of each other. Publish/subscribe systems have gained new momentum thanks to the Web User Generated Content (UCG) paradigm, with users generating their own content Mobile Ad Hoc Networking: Cutting Edge Directions, Second Edition. Edited by Stefano Basagni, Marco Conti, Silvia Giordano, and Ivan Stojmenovic. © 2013 by The Institute of Electrical and Electronics Engineers, Inc. Published 2013 by John Wiley & Sons, Inc. 453 454 DATA DISSEMINATION IN