Valerio Schiavoni

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The Service Component Architecture (SCA) is a technology agnostic standard for developing and deploying distributed service-oriented applications. However, SCA does not define standard means for runtime manageability (including introspection and reconfiguration) of SOA applications and of their supporting environment. This paper presents the FraSCAti(More)
Gossip peer sampling protocols now represent a solid basis to build and maintain peer to peer (p2p) overlay networks. They provide peers with a random sample of the network and maintain connectivity in highly dynamic settings. They rely on the assumption that, at any time, each peer is able to communicate with any other peer. Yet, this ignores the fact that(More)
A wide range of distributed applications requires some form of confidential communication between groups of users. In particular, the messages exchanged between the users and the identity of group members should not be visible to external observers. Classical approaches to confidential group communication rely upon centralized servers, which limit(More)
Slicing is a distributed systems primitive that allows to autonomously partition a large set of nodes based on node-local attributes. Slicing is decisive for automatically provisioning system resources for different services, based on their requirements or importance. One of the main limitations of existing slicing protocols is that only single dimension(More)
Many distributed applications, such as collaborative Web mapping, collaborative feedback and ranking, or bug reporting systems, rely on the aggregation of privacy-sensitive information gathered from human users. This information is typically aggregated at servers and later used as the basis for some collaborative service. Expecting that clients trust that(More)
There is an increasing demand for efficient and robust systems able to cope with today's global needs for intensive data dissemination, e.g., media content or news feeds. Unfortunately, traditional approaches tend to focus on one end of the efficiency/robustness design spectrum, by either leveraging rigid structures such as trees to achieve efficient(More)
Denial-of-Service (DoS) attacks are a major concern for modern distributed applications. They exploit weakness in the software in order to make it unavailable to well-behaved users. Building DoS resistant software is still an issue. Solutions relying on the use of annotations have been proposed. Nevertheless, they require modifying the source code of the(More)
Distributed Hash-Tables (DHTs) provide an efficient way to store objects in large-scale peer-to-peer systems. To guarantee that objects are reliably stored, DHTs rely on replication. Several replication strategies have been proposed in the last years. The most efficient ones use predictions about the availability of nodes to reduce the number of object(More)
Today’s intensive demand for data such as live broadcast or news feeds requires efficient and robust dissemination systems. Traditionally, designs focus on extremes of the efficiency/robustness spectrum by either using structures, such as trees for efficiency or by using loosely-coupled epidemic protocols for