This exstended abstract presents an asymmetric and programmable (extensible) approach to pervasive computing. The idea is to off-load computations from light portable clients into a back-bone of seamlessly integrated servers. This way, a user can extend and personalize his pervasive computational environment by installing computations following his trajectory throughout the day. Focus on this extended ...

Events injected by publishers into a publish/subscribe system may reach users through a variety of devices: a stationary desktop, a laptop, a mobile phone, etc. We argue that the "last hop" -- from the network to the output device -- has unique properties, owing to the mobile nature of these devices, and as such demands special consideration. In particular, user's preferences and location may limit ...

It is becoming clear that modern middleware platforms must provide both deploy-time configuration and run-time reconfiguration to accommodate rapid changing requirements and also to be able to operate in dynamic environments. J2EE is a key example of a middleware architecture that supports enterprise applications via its Enterprise JavaBeans (EJB) component model. EJB provides limited configurability ...

The main purpose of this paper is to illuminate two types of unwanted traffic in a publish/subscribe system -- malicious (spam, DoS attacks) and vain (unused events) -- and suggest a general mechanism for minimizing their effects. We do this by augmenting the classic publish/subscribe interface with volume-limiting parameters -- a combination of attributes assigned to events by publishers and ...

Experiments run on a Grid, consisting of clusters administered by multiple organizations connected by shared wide area networks (WANs), may not be reproducible. First, traffic on the WAN cannot be controlled. Second, allocating the same resources for subsequent experiments can be difficult. Longcut solves both problems by splitting a single cluster into several parts, and for each part having one ...

Traditionally, transactions are flat and atomic possessing the ACID properties. The traditional ACID transaction model has clear limitations in new application domains where transactions often are long-running and require properties that go beyond ACID. Structuring a long-running transaction as an ACID transaction will impede both performance and concurrency. To meet extended and varying transactional ...

Because software security patches relay information about vulnerabilities, they can be reverse engineered into exploits. Tools for doing this already exist. As a result, there is a race between hackers and end-users to first obtain patches. In this paper we present and evaluate FirePatch, an intrusion-tolerant dissemination mechanism that combines encryption, replication, and sandboxing such that ...

Computer games with distributed functionality, such as most modern multiplayer games, provide a rich environment in which one can experiment with high performance distribution of computational and graphical resources. Their extremely high requirements for processing power and consistent visual output create a platform with unique demands. Current tiled display walls provide, as a consequence of ...

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