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52
Programming pervasive and mobile computing applications with the tota middleware
- PerCom 2004. Proceedings of the Second IEEE Annual Conference on
, 2004
"... Pervasive and mobile computing call for suitable middleware and programming models to support the activities of complex software systems in dynamic network environments. In this paper we present TOTA (“Tuples On The Air”), a novel middleware and programming approach for supporting adaptive context-a ..."
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Cited by 123 (33 self)
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Pervasive and mobile computing call for suitable middleware and programming models to support the activities of complex software systems in dynamic network environments. In this paper we present TOTA (“Tuples On The Air”), a novel middleware and programming approach for supporting adaptive context-aware activities in pervasive and mobile computing scenarios. The key idea in TOTA is to rely on spatially distributed tuples, adaptively propagated across a network on the basis of application-specific rules, for both representing contextual information and supporting uncoupled interactions between application components. TOTA promotes a simple way of programming that facilitates access to distributed information, navigation in complex environments, and achievement of complex coordination tasks in a fully distributed and adaptive way, mostly freeing programmers and system managers form the need to take care of lowlevel issues related to network dynamics. This paper includes both application examples to clarify concepts and performance figures to show the feasibility of the approach.
Spidercast: A scalable interest aware overlay for topic-based pub/sub communication
- In Proceedings of the 2007 inaugural international conference on Distributed event-based systems (DEBS 2007
, 2006
"... We introduce SpiderCast, a distributed protocol for constructing scalable churn-resistant overlay topologies for supporting decentralized topic-based pub/sub communication. SpiderCast is designed to effectively tread the balance between average overlay degree and communication cost of event dissemin ..."
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Cited by 41 (11 self)
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We introduce SpiderCast, a distributed protocol for constructing scalable churn-resistant overlay topologies for supporting decentralized topic-based pub/sub communication. SpiderCast is designed to effectively tread the balance between average overlay degree and communication cost of event dissemination. It employs a novel coverage-optimizing heuristic in which the nodes utilize partial subscription views (provided by a decentralized membership service) to reduce the average node degree while guaranteeing (with high probability) that the events posted on each topic can be routed solely through the nodes interested in this topic (in other words, the overlay is topic-connected). SpiderCast is unique in maintaining an overlay topology that scales well with the average number of topics a node is subscribed to, assuming the subscriptions are correlated insofar as found in most typical workloads. Furthermore, the degree grows logarithmically in the total number of topics, and slowly decreases as the number of nodes increases. We show experimentally that, for many practical workloads, the SpiderCast overlays are both topic-connected and have a low per-topic diameter while requiring each node to maintain a low average number of connections. These properties are satisfied even in very large settings involving up to 10, 000 nodes, 1, 000 topics, and 70 subscriptions per-node, and under high churn rates. In addition, our results demonstrate that, in a large setting, the average node degree in SpiderCast is at least 45 % smaller than in other overlays typically used to support decentralized pub/sub communication (such as e.g., similarity-based, rings-based, and random overlays).
Distributed Event Routing in Publish/Subscribe Communication Systems: a Survey
, 2005
"... Abstract. Distributed event routing has emerged as a key technology for achieving scalable information dissemination. In particular it has been used as preferential communication backbone within publish/subscribe communication system. Its aim is to reduce the network and computational overhead per e ..."
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Cited by 37 (3 self)
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Abstract. Distributed event routing has emerged as a key technology for achieving scalable information dissemination. In particular it has been used as preferential communication backbone within publish/subscribe communication system. Its aim is to reduce the network and computational overhead per event diffusion to a set (possibly large) of interested recipients. This paper introduces an unifying framework, namely a publish/subscribe architecture, that points out the functional decomposition between event-based routing layer, the overlay infrastructure layer and the network protocols layer. Hence the paper, firstly, surveys current algorithms for event based routing and possible overlay infrastructures in wired and mobile systems and, secondly, it discusses how and when single solutions at each level can be combined in the publish/subscribe architecture. Finally the paper positions existing publish/subscribe systems within the proposed architecture. 1
Efficient publish/subscribe through a self-organizing broker overlay and its application to SIENA
, 2005
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Load Balancing Content-Based Publish/Subscribe Systems
, 2010
"... Distributed content-based publish/subscribe systems suffer from performance degradation and poor scalability caused by uneven load distributions typical in real-world applications. The reason for this shortcoming is the lack of a load balancing scheme. This article proposes a load balancing solution ..."
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Cited by 11 (3 self)
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Distributed content-based publish/subscribe systems suffer from performance degradation and poor scalability caused by uneven load distributions typical in real-world applications. The reason for this shortcoming is the lack of a load balancing scheme. This article proposes a load balancing solution specifically tailored to the needs of content-based publish/subscribe systems that is distributed, dynamic, adaptive, transparent, and accommodates heterogeneity. The solution consists of three key contributions: a load balancing framework, a novel load estimation algorithm, and three offload strategies. A working prototype of our solution is built on an open-sourced content-based publish/subscribe system and evaluated on PlanetLab, a cluster testbed, and in simulations. Real-life experiment results show that the proposed load balancing solution is efficient with less than 0.2 % overhead; effective in distributing and balancing load originating from a single server to all available servers in the network; and capable of preventing overloads to preserve system
Enforcing Routing Consistency in Structured Peer-to-Peer Overlays: Should We and Could We?
, 2006
"... In this paper, we argue that enforcing routing consistency in keybased routing (KBR) protocols can simplify P2P application design and make structured P2P overlays suitable for more applications. We define two levels of routing consistency semantics, namely weakly consistent KBR and strongly consist ..."
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Cited by 11 (3 self)
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In this paper, we argue that enforcing routing consistency in keybased routing (KBR) protocols can simplify P2P application design and make structured P2P overlays suitable for more applications. We define two levels of routing consistency semantics, namely weakly consistent KBR and strongly consistent KBR. We focus on an algorithm that provides strong consistency based on group membership service and weakly consistent KBR. The algorithm provides a continuum of consistency levels for applications with a tunable parameter.
Probabilistic quorum systems in wireless ad hoc networks
- In Proceedings of the 38th IEEE International Conference on Dependable Systems and Networks (DSN-DCCS
, 2008
"... Quorums are a basic construct in solving many fundamental distributed computing problems. One of the known ways of making quorums scalable and efficient is by weakening their intersection guarantee to being probabilistic. This paper explores several access strategies for implementing probabilistic q ..."
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Cited by 10 (5 self)
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Quorums are a basic construct in solving many fundamental distributed computing problems. One of the known ways of making quorums scalable and efficient is by weakening their intersection guarantee to being probabilistic. This paper explores several access strategies for implementing probabilistic quorums in ad hoc networks. In particular, we present the first detailed study of asymmetric probabilistic bi-quorum systems, that allow to mix different access strategies and different quorums sizes, while guaranteeing the desired intersection probability. We show the advantages of asymmetric probabilistic bi-quorum systems in ad hoc networks. Such an asymmetric construction is also useful for other types of networks with non uniform access costs (e.g, peer-to-peer networks). The paper includes both a formal analysis of these approaches backed up by an extensive simulation based study. In particular, we show that one of the strategies that uses Random Walks, exhibits the smallest communication overhead, thus being very attractive for ad hoc networks. Categories and Subject Descriptors: C.2.1 [Comp.-Communication Networks]: Network Architecture and Design—Wireless communication;
Adaptive Batching for Replicated Servers ∗
"... This paper presents two novel generic adaptive batching schemes for replicated servers. Both schemes are oblivious to the underlying communication protocols. Our novel schemes adapt their batching levels automatically and immediately according to the current communication load. This is done without ..."
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Cited by 8 (0 self)
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This paper presents two novel generic adaptive batching schemes for replicated servers. Both schemes are oblivious to the underlying communication protocols. Our novel schemes adapt their batching levels automatically and immediately according to the current communication load. This is done without any explicit monitoring or calibration of the system. Additionally, the paper includes a detailed performance evaluation. 1
Content-based Publish/Subscribe using Distributed R-trees
"... Abstract. Publish/subscribe systems provide a useful paradigm for selective data dissemination and most of the complexity related to addressing and routing is encapsulated within the network infrastructure. The challenge of such systems is to organize the peers so as to best match the interests of t ..."
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Cited by 5 (0 self)
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Abstract. Publish/subscribe systems provide a useful paradigm for selective data dissemination and most of the complexity related to addressing and routing is encapsulated within the network infrastructure. The challenge of such systems is to organize the peers so as to best match the interests of the consumers, minimizing false positives and avoiding false negatives. In this paper, we propose and evaluate the use of R-trees for organizing the peers of a content-based routing network. We adapt three well-known variants of R-trees to the content dissemination problem striving to minimize the occurrence of false positives while avoiding false negatives. The effectiveness and accuracy of each structure is analyzed by extensive simulations. 1
Comparing alternative approaches for networking of named objects
- in the future Internet,” in IEEE Workshop on Emerging Design Choices in Name-Oriented Networking (NOMEN
, 2012
"... Abstract—This paper describes and compares alternative ar-chitectures for achieving the functional goals of name ori-ented networking. The CCN (content-centric network) scheme proposed by Van Jacobson is contrasted with hybrid name and address based routing proposed in conjunction with the MobilityF ..."
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Cited by 5 (0 self)
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Abstract—This paper describes and compares alternative ar-chitectures for achieving the functional goals of name ori-ented networking. The CCN (content-centric network) scheme proposed by Van Jacobson is contrasted with hybrid name and address based routing proposed in conjunction with the MobilityFirst (MF) future Internet architecture. In a CCN network, routers forward data directly on content names (such as URNs), achieving elegant and efficient retrieval of content files; the framework can also be extended to other communications services such as VoIP. The MF scheme supports name-based com-munication services by introducing the concept of a flat ‘globally unique identifier (GUID)’, which is used as the authoritative header for routing. Further, the GUID is dynamically mapped to one or more topological network addresses using a global name resolution service (GNRS). This leads to a hybrid GUID and network address based routing (HGN) scheme in which routers operate with both flat names (GUIDs) and network addresses, reducing routing table size and overhead at the cost of a fast distributed service for dynamic mapping of names to addresses. Protocol operations for both CCN and HGN are outlined in context of specific services including content retrieval, unicast and mobility. Preliminary evaluations of scalability and performance for both schemes are given using simple analytical models and selected results from Internet-scale simulations for GNRS and BGP. I.
