International Workshop on Mobile Opportunistic Networks最新文献

{"title":"Random graph models for wireless and social networks: keynote talk abstract","authors":"M. Grossglauser","doi":"10.1145/2159576.2159578","DOIUrl":"https://doi.org/10.1145/2159576.2159578","url":null,"abstract":"Operating large-scale social applications over opportunistic wireless networks entails many fascinating engineering challenges. We strive for robust and efficient algorithms for specific problems like opportunistic forwarding, routing, or publish-subscribe, and we want to ascertain global properties like security, privacy, fairness, and high performance. One particular set of challenges concerns the scalability of this whole endeavor: is it fundamentally possible for such applications and underlying methods to scale up to large networks, without jeopardizing desirable system properties?\u0000 We discuss recent progress in some of the key problems in this area at three conceptual layers: opportunistic forwarding, routing under mobility, and social network privacy.\u0000 Opportunistic forwarding exploits the random broadcast nature of the wireless channel and the availability of multiple \"good\" routes towards a destination. This approach can deliver a message to its destination at a potentially lower expected cost than over a single shortest path. We introduce a forwarding algorithm and associated \"anypath metric\" that is optimal, building on the observation that no single-path metric can achieve optimality in general.\u0000 In routing under mobility, the key challenge is to keep track of the changing network topology, so that efficient routes can be computed at any time between any pair of nodes. We ask whether there exist low-overhead schemes that produce low-stretch routes, even in large networks where all the nodes are mobile. We present a scheme that maintains a hierarchical structure within which constant-stretch routes can be efficiently computed between every pair of nodes. The scheme rebuilds each level of the hierarchy periodically, at a rate that decreases exponentially with the level of the hierarchy, and achieves constant stretch under a mild smoothness condition on the mobility process.\u0000 Finally, we address the problem of the privacy of an anonymized social network. The specific challenge is the sharing or public release of anonymized network data without accidentally leaking personally identifiable information (PII). Unfortunately, it is often difficult to ascertain that sophisticated statistical techniques, potentially employing additional external data sources, are unable to break anonymity. We show an asymptotic condition, based on a random graph model, under which a computationally powerful adversary would be able to re-identify the anonymized node identities. This has important implications for privacy policies in social network structures.\u0000 What binds the above problem formulations and results together is our reliance on stochastic network models that retain only the salient features of each problem. These abstractions allow us to make precise statements about scalability to very large systems. We hope that these results complement and inform more focused work on methods, protocols, and applications for mobile, opportunistic, and social netwo","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116636257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demo of a collaborative music sharing system","authors":"Zhaofei Chen, Emre A. Yavuz, G. Karlsson","doi":"10.1145/2159576.2159593","DOIUrl":"https://doi.org/10.1145/2159576.2159593","url":null,"abstract":"We demonstrate a wireless real-time music-sharing application that lets users play music directly from their mobiles through a jukebox. We have designed and implemented the application by using a previously developed content-centric opportunistic networking middleware. The jukebox plays the music file that is first in its playlist by streaming it in real-time from the publishing user device. All users can observe the collaboratively formed playlist on their mobiles in real-time. The application shows the usefulness of our middleware and demonstrates a new form of situated applications. The application handles churn and garbage collection after departed users.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125597375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On context awareness and social distance in human mobility traces","authors":"Anna Förster, Kamini Garg, H. A. Nguyen, S. Giordano","doi":"10.1145/2159576.2159581","DOIUrl":"https://doi.org/10.1145/2159576.2159581","url":null,"abstract":"Opportunistic networks consist of mobile devices, carried by people in their everyday lives. They organize autonomously to exchange data with direct neighbors without the use of any infrastructural services. Since the devices are carried by humans, one of the main challenges to consider in opportunistic networks is the human mobility behavior. However, little work exists on how the social behavior of people drives their mobility behavior and how this context information can be systematically leveraged for opportunistic networking applications. This paper tackles this problem by providing both experimental and theoretical analysis of human mobility context information. We present a novel real world experiment with sensor nodes carried by people to demonstrate and study the effect of context on people mobility. Furthermore, we define a novel metric of social distance to put this new evidence on solid mathematical foundation. Thus, our work puts a basis to systematically leveraging context information for opportunistic networking applications and services. Additionally, our experimental data traces enable testing and evaluation of such novel services in a real world scenario.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124398867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Making the most of your contacts: transfer ordering in data-centric opportunistic networks","authors":"C. Rohner, Fredrik Bjurefors, P. Gunningberg, L. McNamara, Erik Nordström","doi":"10.1145/2159576.2159589","DOIUrl":"https://doi.org/10.1145/2159576.2159589","url":null,"abstract":"Opportunistic networks use unpredictable and time-limited contacts to disseminate data. Therefore, it is important that protocols transfer useful data when contacts do occur. Specifically, in a data-centric network, nodes benefit from receiving data relevant to their interests. To this end, we study five strategies to select and order the data to be exchanged during a limited contact, and measure their ability to promptly and efficiently deliver highly relevant data.\u0000 Our trace-driven experiments on an emulation testbed suggest that nodes benefit in the short-term from ordering data transfers to satisfy local interests. However, this can lead to suboptimal long-term system performance. Restricting sharing based on matching nodes' interests can lead to segregation of the network, and limit useful dissemination of data. A non-local understanding of other nodes' interests is necessary to effectively move data across the network. If ordering of transfers for data relevance is not explicitly considered performance is comparable to random, which limits the delivery of individually relevant data.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116307484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"QuickSilver: application-driven inter- and intra-cluster communication in Vanets","authors":"R. Crepaldi, Mehedi Bakht, R. Kravets","doi":"10.1145/2159576.2159591","DOIUrl":"https://doi.org/10.1145/2159576.2159591","url":null,"abstract":"Support for efficient vehicle-to-vehicle communication is increasingly more important with the emergence of newer vehicles equipped with one or more wireless interfaces. While the applications aimed at such networks range from car-to-car chats to sharing dynamic map data, current approaches to inter-vehicular networking have been designed based on either node-centric or content-centric communication, but not both. The challenge for a comprehensive solution arises from the high mobility of nodes as well as the heterogeneity of contact patterns. In this paper, we propose QuickSilver, a system architecture that meets this challenge by leveraging an intrinsic characteristic of vehicular networks - clustering. By being aware of such clustering, Quicksilver enables a seamless integration of two networking paradigms, one for node-centric communication between members of the same cluster, the other for effective content dissemination and exchange during short cluster-to-cluster contacts. To achieve this goal efficiently, Quicksilver employs a novel combination of channel management and light-weight clustering that enables detection and management of headless, multi-hop clusters at very low cost. Evaluation results show that Quicksilver enables close-to-optimal performance when nodes across different clusters communicate.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129546582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From ego network to social network models","authors":"M. Conti, A. Passarella, F. Pezzoni","doi":"10.1145/2159576.2159600","DOIUrl":"https://doi.org/10.1145/2159576.2159600","url":null,"abstract":"The development of routing protocols for human pervasive networks can not disregard contextual information. Social network models can help researches giving information about human behaviors, e.g. estimating contact opportunities between nodes. In a previous work we defined a model for ego networks while in this work we present a method to integrate ego networks and obtain synthetic social networks ready-to-use for the development of routing protocols.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134242534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Illinois vehicular project, live data sampling and opportunistic internet connectivity","authors":"R. Crepaldi, Ryan Beavers, Braden Ehrat, R. Kravets","doi":"10.1145/2159576.2159597","DOIUrl":"https://doi.org/10.1145/2159576.2159597","url":null,"abstract":"Embedded sensors in mobile devices such as cars and smart phones present new opportunities to collect data and explore a new environment. Vehicular Networks are highly mobile and widely spread, and the broad deployment of embedded sensors will lead to the establishment of large participatory sensing systems and enable the generation of large amounts of data. A major challenge is efficiently collecting, storing and sharing all this data. Vehicular networks present several bottlenecks that must be considered. Data could be kept locally using the network as a distributed storage system. However, the high mobility and frequent disconnection could cause a continuos migration of data, and possibly its loss. Replication is a possible solution to this problem, using ad-hoc connections between vehicles. Additionally, capacity is also a challenge. Using a mobile connection such as 3G or WiMax, the information can be uploaded and retrieved from a central storage unit. However, those networks are already pushed to the limit to serve existing mobile Internet access. The increasing number of devices generating data and the rates at which this data is generated will quickly overwhelm the infrastructure. On the other hand, energy efficiency might not be a primary concern for vehicles, given that when a vehicle is on, it generates enough energy for full-power radio operation. Nevertheless, a vehicle can be parked for several days, and thus the power for communication would drain the battery. Thus, even in vehicular networks, energy efficient protocols can and sometimes must be used. Efforts to tackle these challenges led to the design of systems such as Locus [4]. However, it is still not fully understood how will these heavy sensing tasks, the peer to peer communication, and the energy efficiency interact. To anServer","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121235177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vicinity-based DTN characterization","authors":"Tiphaine Phe-Neau, M. Amorim, V. Conan","doi":"10.1145/2159576.2159586","DOIUrl":"https://doi.org/10.1145/2159576.2159586","url":null,"abstract":"We relax the traditional definition of contact and intercontact times by bringing the notion of vicinity into the game. We propose to analyze disruption-tolerant networks (DTN) under the assumption that nodes are in k-contact when they remain within a few hops from each other and in k-intercontact otherwise (where k is the maximum number of hops characterizing the vicinity). We make interesting observations when analyzing several real-world and synthetic mobility traces. We detect a number of unexpected behaviors when analyzing k-contact distributions; in particular, we observe that in some datasets the average k-contact time decreases as we increase k. In fact, we observe that many nodes spend a non-negligible amount of time in each other's vicinity without coming into direct contact. We also show that a small k (typically between 3 and 4) is sufficient to capture most communication opportunities.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132065505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"404 not found: a quest for DTN applications","authors":"J. Ott","doi":"10.1145/2159576.2159579","DOIUrl":"https://doi.org/10.1145/2159576.2159579","url":null,"abstract":"1. EXTENDED ABSTRACT Delay-tolerant Networking (DTN) [3] has moved a long way from its—for many probably somewhat elite—origin of a technology for an Interplanetary Internet in the late 1990s to an established research discipline. One major contributor to this trend was the observation that quite a few terrestrial networks exhibit delay-tolerant properties, albeit of different nature: from sparse mobile ad-hoc to sensor networks to mobile Internet access, we find delay tolerance as an important element to describe communication behavior and to design protocols suitable for operation in the respective challenged networking environment. And even fixed infrastructure networks may benefit from delay-tolerant approaches to data transmission [7]—as did UUNet decades ago, when forwarding mails and news in a multi-hop store-and-forward fashion enabled communication involving machines that were not “always on” in the first place. Delay-tolerant networking has contributed to our understanding of networking at least in a twofold manner:","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130559341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utility-based forwarding: a comparison in different mobility scenarios","authors":"E. Pagani, G. P. Rossi","doi":"10.1145/2159576.2159585","DOIUrl":"https://doi.org/10.1145/2159576.2159585","url":null,"abstract":"Several proposals are available in the literature that deal with the problem of message forwarding in Opportunistic Networks (ONs). These proposals attempt to derive the path from source to destination that minimizes delivery latency and traveled hops, and maximizes the probability of successful delivery, while saving the overall system resources through a limitation of the number of message copies. Utilitybased forwarding achieves these goals through the use of functions that discriminate among nodes in terms of their utility to reach a destination. Although the approach is very promising, so far, there is no understanding about the tight relationship between utility functions and the mobility scenario in which they operate and, as a consequence, we are unable to design efficient solutions for practical ONs.\u0000 In this work, we focus on this point by analysing five well known utility functions in five different scenarios. We establish relationships between the mechanisms adopted by the utility functions to discriminate among candidate relays, and the characteristics of the environment in terms of people mobility and the structure of their communities. The results can be useful to select an appropriate forwarding mechanism when deploying an experimental Opportunistic Network, and to design a novel utility function able to adapt to variable mobility patterns.","PeriodicalId":198518,"journal":{"name":"International Workshop on Mobile Opportunistic Networks","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129464634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}