8,378 research outputs found
Mediator-assisted multi-source routing in information-centric networks
Among the new communication paradigms recently proposed, information-centric networking (ICN) is able to natively support content awareness at the network layer shifting the focus from hosts (as in traditional IP networks) to information objects. In this paper, we exploit the intrinsic content-awareness ICN features to design a novel multi-source routing mechanism. It involves a new network entity, the ICN mediator, responsible for locating and delivering the requested information objects that are chunked and stored at different locations. Our approach imposes very limited signalling overhead, especially for large chunk size (MBytes). Simulations show significant latency reduction compared to traditional routing approaches
Reliable Messaging to Millions of Users with MigratoryData
Web-based notification services are used by a large range of businesses to
selectively distribute live updates to customers, following the
publish/subscribe (pub/sub) model. Typical deployments can involve millions of
subscribers expecting ordering and delivery guarantees together with low
latencies. Notification services must be vertically and horizontally scalable,
and adopt replication to provide a reliable service. We report our experience
building and operating MigratoryData, a highly-scalable notification service.
We discuss the typical requirements of MigratoryData customers, and describe
the architecture and design of the service, focusing on scalability and fault
tolerance. Our evaluation demonstrates the ability of MigratoryData to handle
millions of concurrent connections and support a reliable notification service
despite server failures and network disconnections
Internames: a name-to-name principle for the future Internet
We propose Internames, an architectural framework in which names are used to
identify all entities involved in communication: contents, users, devices,
logical as well as physical points involved in the communication, and services.
By not having a static binding between the name of a communication entity and
its current location, we allow entities to be mobile, enable them to be reached
by any of a number of basic communication primitives, enable communication to
span networks with different technologies and allow for disconnected operation.
Furthermore, with the ability to communicate between names, the communication
path can be dynamically bound to any of a number of end-points, and the
end-points themselves could change as needed. A key benefit of our architecture
is its ability to accommodate gradual migration from the current IP
infrastructure to a future that may be a ubiquitous Information Centric
Network. Basic building blocks of Internames are: i) a name-based Application
Programming Interface; ii) a separation of identifiers (names) and locators;
iii) a powerful Name Resolution Service (NRS) that dynamically maps names to
locators, as a function of time/location/context/service; iv) a built-in
capacity of evolution, allowing a transparent migration from current networks
and the ability to include as particular cases current specific architectures.
To achieve this vision, shared by many other researchers, we exploit and expand
on Information Centric Networking principles, extending ICN functionality
beyond content retrieval, easing send-to-name and push services, and allowing
to use names also to route data in the return path. A key role in this
architecture is played by the NRS, which allows for the co-existence of
multiple network "realms", including current IP and non-IP networks, glued
together by a name-to-name overarching communication primitive.Comment: 6 page
Improving the Scalability of DPWS-Based Networked Infrastructures
The Devices Profile for Web Services (DPWS) specification enables seamless
discovery, configuration, and interoperability of networked devices in various
settings, ranging from home automation and multimedia to manufacturing
equipment and data centers. Unfortunately, the sheer simplicity of event
notification mechanisms that makes it fit for resource-constrained devices,
makes it hard to scale to large infrastructures with more stringent
dependability requirements, ironically, where self-configuration would be most
useful. In this report, we address this challenge with a proposal to integrate
gossip-based dissemination in DPWS, thus maintaining compatibility with
original assumptions of the specification, and avoiding a centralized
configuration server or custom black-box middleware components. In detail, we
show how our approach provides an evolutionary and non-intrusive solution to
the scalability limitations of DPWS and experimentally evaluate it with an
implementation based on the the Web Services for Devices (WS4D) Java Multi
Edition DPWS Stack (JMEDS).Comment: 28 pages, Technical Repor
Digital Ecosystems: Ecosystem-Oriented Architectures
We view Digital Ecosystems to be the digital counterparts of biological
ecosystems. Here, we are concerned with the creation of these Digital
Ecosystems, exploiting the self-organising properties of biological ecosystems
to evolve high-level software applications. Therefore, we created the Digital
Ecosystem, a novel optimisation technique inspired by biological ecosystems,
where the optimisation works at two levels: a first optimisation, migration of
agents which are distributed in a decentralised peer-to-peer network, operating
continuously in time; this process feeds a second optimisation based on
evolutionary computing that operates locally on single peers and is aimed at
finding solutions to satisfy locally relevant constraints. The Digital
Ecosystem was then measured experimentally through simulations, with measures
originating from theoretical ecology, evaluating its likeness to biological
ecosystems. This included its responsiveness to requests for applications from
the user base, as a measure of the ecological succession (ecosystem maturity).
Overall, we have advanced the understanding of Digital Ecosystems, creating
Ecosystem-Oriented Architectures where the word ecosystem is more than just a
metaphor.Comment: 39 pages, 26 figures, journa
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