843 research outputs found
Architectural Considerations for a Self-Configuring Routing Scheme for Spontaneous Networks
Decoupling the permanent identifier of a node from the node's
topology-dependent address is a promising approach toward completely scalable
self-organizing networks. A group of proposals that have adopted such an
approach use the same structure to: address nodes, perform routing, and
implement location service. In this way, the consistency of the routing
protocol relies on the coherent sharing of the addressing space among all nodes
in the network. Such proposals use a logical tree-like structure where routes
in this space correspond to routes in the physical level. The advantage of
tree-like spaces is that it allows for simple address assignment and
management. Nevertheless, it has low route selection flexibility, which results
in low routing performance and poor resilience to failures. In this paper, we
propose to increase the number of paths using incomplete hypercubes. The design
of more complex structures, like multi-dimensional Cartesian spaces, improves
the resilience and routing performance due to the flexibility in route
selection. We present a framework for using hypercubes to implement indirect
routing. This framework allows to give a solution adapted to the dynamics of
the network, providing a proactive and reactive routing protocols, our major
contributions. We show that, contrary to traditional approaches, our proposal
supports more dynamic networks and is more robust to node failures
DHT-based functionalities using hypercubes
Decoupling the permanent identifi er of a node from the node's topology-dependent address is a promising approach toward completely scalable self-organizing networks. Existing solutions use a logical tree-like structure that, although allowing for simple address assignment and management, lead to low route selection flexibility. This clearly results in low routing performance and poor resilience to failures. In this paper, we propose to increase the number of candidate paths by using incomplete hypercubes. We will see that this solution can cover a wide range of applications by adapting to the dynamics of the network1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI
DHT-based functionalities using hypercubes
Decoupling the permanent identifi er of a node from the node's topology-dependent address is a promising approach toward completely scalable self-organizing networks. Existing solutions use a logical tree-like structure that, although allowing for simple address assignment and management, lead to low route selection flexibility. This clearly results in low routing performance and poor resilience to failures. In this paper, we propose to increase the number of candidate paths by using incomplete hypercubes. We will see that this solution can cover a wide range of applications by adapting to the dynamics of the network1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI
Weaving quantum optical frequency combs into continuous-variable hypercubic cluster states
Cluster states with higher-dimensional lattices that cannot be physically
embedded in three-dimensional space have important theoretical interest in
quantum computation and quantum simulation of topologically ordered
condensed-matter systems. We present a simple, scalable, top-down method of
entangling the quantum optical frequency comb into hypercubic-lattice
continuous-variable cluster states of a size of about 10^4 quantum field modes,
using existing technology. A hypercubic lattice of dimension D (linear, square,
cubic, hypercubic, etc.) requires but D optical parametric oscillators with
bichromatic pumps whose frequency splittings alone determine the lattice
dimensionality and the number of copies of the state.Comment: 8 pages, 5 figures, submitted for publicatio
Inference of Ancestral Recombination Graphs through Topological Data Analysis
The recent explosion of genomic data has underscored the need for
interpretable and comprehensive analyses that can capture complex phylogenetic
relationships within and across species. Recombination, reassortment and
horizontal gene transfer constitute examples of pervasive biological phenomena
that cannot be captured by tree-like representations. Starting from hundreds of
genomes, we are interested in the reconstruction of potential evolutionary
histories leading to the observed data. Ancestral recombination graphs
represent potential histories that explicitly accommodate recombination and
mutation events across orthologous genomes. However, they are computationally
costly to reconstruct, usually being infeasible for more than few tens of
genomes. Recently, Topological Data Analysis (TDA) methods have been proposed
as robust and scalable methods that can capture the genetic scale and frequency
of recombination. We build upon previous TDA developments for detecting and
quantifying recombination, and present a novel framework that can be applied to
hundreds of genomes and can be interpreted in terms of minimal histories of
mutation and recombination events, quantifying the scales and identifying the
genomic locations of recombinations. We implement this framework in a software
package, called TARGet, and apply it to several examples, including small
migration between different populations, human recombination, and horizontal
evolution in finches inhabiting the Gal\'apagos Islands.Comment: 33 pages, 12 figures. The accompanying software, instructions and
example files used in the manuscript can be obtained from
https://github.com/RabadanLab/TARGe
Complex queries over decentralised systems for geodata retrieval
none4sìDecentralised systems have been proved to be quite effective to allow for trusted and accountable data sharing, without the need to resort to a centralised party that collects all the information. While complete decentralisation provides important advantages in terms of data sovereignty, absence of bottlenecks and reliability, it also adds some issues concerned with efficient data lookup and the possibility to implement complex queries without reintroducing centralised components. In this paper, we describe a system that copes with these issues, thanks to a multi-layer lookup scheme based on Distributed Hash Tables that allows for multiple keyword-based searches. The service of peer nodes participating in this discovery service is controlled and rewarded for their contribution. Moreover, the governance of this process is completely automated through the use of smart contracts, thus building a Decentralised Autonomous Organization (DAO). Finally, we present a use case where road hazards are collected in order to test the goodness of our system for geodata retrieval. Then, we show results from a performance evaluation that confirm the viability of the proposal. © 2022 The Authors. IET Networks published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.
openZichichi, Mirko; Serena, Luca; Ferretti, Stefano; D'Angelo, GabrieleZichichi, Mirko; Serena, Luca; Ferretti, Stefano; D'Angelo, Gabriel
Advances in Bosonic Quantum Error Correction with Gottesman-Kitaev-Preskill Codes: Theory, Engineering and Applications
Encoding quantum information into a set of harmonic oscillators is considered
a hardware efficient approach to mitigate noise for reliable quantum
information processing. Various codes have been proposed to encode a qubit into
an oscillator -- including cat codes, binomial codes and
Gottesman-Kitaev-Preskill (GKP) codes. These bosonic codes are among the first
to reach a break-even point for quantum error correction. Furthermore, GKP
states not only enable close-to-optimal quantum communication rates in bosonic
channels, but also allow for error correction of an oscillator into many
oscillators. This review focuses on the basic working mechanism, performance
characterization, and the many applications of GKP codes, with emphasis on
recent experimental progress in superconducting circuit architectures and
theoretical progress in multimode GKP qubit codes and
oscillators-to-oscillators (O2O) codes. We begin with a preliminary
continuous-variable formalism needed for bosonic codes. We then proceed to the
quantum engineering involved to physically realize GKP states. We take a deep
dive into GKP stabilization and preparation in superconducting architectures
and examine proposals for realizing GKP states in the optical domain (along
with a concise review of GKP realization in trapped-ion platforms). Finally, we
present multimode GKP qubits and GKP-O2O codes, examine code performance and
discuss applications of GKP codes in quantum information processing tasks such
as computing, communication, and sensing.Comment: 77+5 pages, 31 figures. Minor bugs fixed in v2. comments are welcome
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