2013
Other
Restricted
ENGAGED - Roadmap templates to support the cluster members in the assembly of raw roadmaps
Braun A, Chessa S, Fullaondo Zabala A
The deliverable D4.1 - Roadmap templates to support the cluster members in the assembly of raw roadmaps is the first deliverable of WP4. The purpose of this document is to describe the procedure and provide supporting documents that will be used in creating the ENGAGED roadmaps as final results of the work package. The document first gives an overview of the rationale in deciding on the structure of the ENGAGED roadmap, using best practices by third party sources. In the following the roadmap template is described in detail. The next part summarises the Action Plans of the different Action Groups within EIP AHA. The input of those to the ENGAGED roadmap is discussed in detail and potential topics for the ENGAGED workshops are suggested. The next part of the document outlines templates for both workshop agenda and minutes that are specifically tailored to simplify the collection of the inputs relevant to the future roadmaps. Help is provided to the minute takers on filling out the templates, by giving detailed examples on all relevant parts and sections. The document concludes with a résumé and two annexes providing two blank templates for structural roadmap and workshop summary, respectively.Project(s): European Network Group for Ageing Well and its Deployment
Braun A, Chessa S, Fullaondo Zabala A
The deliverable D4.1 - Roadmap templates to support the cluster members in the assembly of raw roadmaps is the first deliverable of WP4. The purpose of this document is to describe the procedure and provide supporting documents that will be used in creating the ENGAGED roadmaps as final results of the work package. The document first gives an overview of the rationale in deciding on the structure of the ENGAGED roadmap, using best practices by third party sources. In the following the roadmap template is described in detail. The next part summarises the Action Plans of the different Action Groups within EIP AHA. The input of those to the ENGAGED roadmap is discussed in detail and potential topics for the ENGAGED workshops are suggested. The next part of the document outlines templates for both workshop agenda and minutes that are specifically tailored to simplify the collection of the inputs relevant to the future roadmaps. Help is provided to the minute takers on filling out the templates, by giving detailed examples on all relevant parts and sections. The document concludes with a résumé and two annexes providing two blank templates for structural roadmap and workshop summary, respectively.Project(s): European Network Group for Ageing Well and its Deployment
2002
Journal article
Restricted
Self-diagnostic tools of the apemille parallel machine
Chessa S, Maestrini P, Errico W, Sallay B, Schifano F, Tripiccione R
The authors describe the self-diagnostic tools of the APEmille SIMD machine, whose logical architecture is a three-dimensional torus of processors. The tools are aimed at implement- ing system-level diagnosis using a comparison model. The diagnostic model accounts for some critical features of the APEmille architecture, and has been validated by means of VHDL simulation. Essentially, diagnostic tools force all processors to synchronously execute the same test program using the same data set, and compare the outputs of adjacent processors in real time. The diagnostic tools also implement a preliminary test session aimed at covering faults that might disrupt the comparison model. The diagnosis algorithm and the test programs used in comparison tests are also described.Source: IEE PROCEEDINGS. COMPUTERS AND DIGITAL TECHNIQUES, vol. 149 (issue 6), pp. 273-279
DOI: 10.1049/ip-cdt:20020808
Metrics:
Chessa S, Maestrini P, Errico W, Sallay B, Schifano F, Tripiccione R
The authors describe the self-diagnostic tools of the APEmille SIMD machine, whose logical architecture is a three-dimensional torus of processors. The tools are aimed at implement- ing system-level diagnosis using a comparison model. The diagnostic model accounts for some critical features of the APEmille architecture, and has been validated by means of VHDL simulation. Essentially, diagnostic tools force all processors to synchronously execute the same test program using the same data set, and compare the outputs of adjacent processors in real time. The diagnostic tools also implement a preliminary test session aimed at covering faults that might disrupt the comparison model. The diagnosis algorithm and the test programs used in comparison tests are also described.Source: IEE PROCEEDINGS. COMPUTERS AND DIGITAL TECHNIQUES, vol. 149 (issue 6), pp. 273-279
DOI: 10.1049/ip-cdt:20020808
Metrics:
See at:
IEE Proceedings - Computers and Digital Techniques 
| CNR IRIS | CNR IRIS
2004
Journal article
Restricted
Diagnosis of symmetric graphs under the BGM model
Albini L P C, Chessa S, Maestrini P
This paper addresses the problem of the identification of faulty units in symmetric systems under the diagnostic model proposed by Barsi, Grandoni and Maestrini (hence called the BGM model). The paper introduces and evaluates an algorithm named DABS (Diagnosis Algorithm for Symmetric System under the BGM model). It is shown that DABS provides a diagnosis unconditionally correct although possibly incomplete. A measure of diagnosis incompleteness IDeg(t) has been defined as the quotient between the number of suspect units (that is, the units that DABS is unable to identify as either good or faulty) and the number of system units. IDeg(t) is evaluated over the set of syndromes deriving from at most t faults under the BGM model. A general approach to the evaluation of IDeg(t) in symmetric systems is introduced, and tight bounds to IDeg(t) are derived for square toroidal grids and hypercubes. This bound is O(t/n) in the case of square toroidal grids of n units.Source: COMPUTER JOURNAL, vol. 47 (issue 1), pp. 85-92
DOI: 10.1093/comjnl/47.1.85
Metrics:
Albini L P C, Chessa S, Maestrini P
This paper addresses the problem of the identification of faulty units in symmetric systems under the diagnostic model proposed by Barsi, Grandoni and Maestrini (hence called the BGM model). The paper introduces and evaluates an algorithm named DABS (Diagnosis Algorithm for Symmetric System under the BGM model). It is shown that DABS provides a diagnosis unconditionally correct although possibly incomplete. A measure of diagnosis incompleteness IDeg(t) has been defined as the quotient between the number of suspect units (that is, the units that DABS is unable to identify as either good or faulty) and the number of system units. IDeg(t) is evaluated over the set of syndromes deriving from at most t faults under the BGM model. A general approach to the evaluation of IDeg(t) in symmetric systems is introduced, and tight bounds to IDeg(t) are derived for square toroidal grids and hypercubes. This bound is O(t/n) in the case of square toroidal grids of n units.Source: COMPUTER JOURNAL, vol. 47 (issue 1), pp. 85-92
DOI: 10.1093/comjnl/47.1.85
Metrics:
See at:
academic.oup.com | The Computer Journal | CNR IRIS | CNR IRIS | www.scopus.com
2005
Journal article
Restricted
Fault recovery mechanism in single-hop sensor networks
Chessa S, Maestrini P
This paper introduces a memory efficient fault recovery scheme for single hop wireless sensor networks, where the network is able to operate independently of the sink node for long periods of time. The proposed scheme does neither require that the sensors be equipped with stable storage nor that they are permanently connected to the sink node. Rather, the sensors cooperate to maintain redundant information in their memories in order to be able to recover the lost information after a failure, and to distribute the recovered information among the memories of the surviving sensors.Source: COMPUTER COMMUNICATIONS, vol. 28 (issue 17), pp. 1877-1886
DOI: 10.1016/j.comcom.2005.01.005
Metrics:
Chessa S, Maestrini P
This paper introduces a memory efficient fault recovery scheme for single hop wireless sensor networks, where the network is able to operate independently of the sink node for long periods of time. The proposed scheme does neither require that the sensors be equipped with stable storage nor that they are permanently connected to the sink node. Rather, the sensors cooperate to maintain redundant information in their memories in order to be able to recover the lost information after a failure, and to distribute the recovered information among the memories of the surviving sensors.Source: COMPUTER COMMUNICATIONS, vol. 28 (issue 17), pp. 1877-1886
DOI: 10.1016/j.comcom.2005.01.005
Metrics:
See at:
Computer Communications | CNR IRIS | CNR IRIS
2004
Conference article
Restricted
Dependable and secure data storage in wireless ad hoc networks: an assessment of DS2
Chessa S, Di Pietro R, Maestrini P
DS2 is a dependable and secure data storage for mobile, wireless networks based on a peer-to-peer paradigm. DS2 provides support to create and share files under a write-once model, and ensures data confidentiality and de-pendability by encoding files in a Redundant Residue Number System. The pa-per analyzes the code efficiency of DS2 using a set of moduli allowing for effi-cient encoding and decoding procedures based on single precision arithmetic, and discusses the security issues. The comparison of DS2 with the Information Dispersal Algorithm approach (IDA) shows that DS2 features security features which are not provided by IDA, while the two approaches are comparable from the viewpoint of code efficiency and encoding/decoding complexity.
Chessa S, Di Pietro R, Maestrini P
DS2 is a dependable and secure data storage for mobile, wireless networks based on a peer-to-peer paradigm. DS2 provides support to create and share files under a write-once model, and ensures data confidentiality and de-pendability by encoding files in a Redundant Residue Number System. The pa-per analyzes the code efficiency of DS2 using a set of moduli allowing for effi-cient encoding and decoding procedures based on single precision arithmetic, and discusses the security issues. The comparison of DS2 with the Information Dispersal Algorithm approach (IDA) shows that DS2 features security features which are not provided by IDA, while the two approaches are comparable from the viewpoint of code efficiency and encoding/decoding complexity.
2001
Journal article
Restricted
Correct and almost complete diagnosis of processor grids
Chessa S, Maestrini P
A new diagnosis algorithm for square grids is introduced. The algorithm always provides correct diagnosis if the number of faulty processors is below T, a bound with T 2 ...n2=3+, which was derived by worst-case analysis. A more effective tool to validate the diagnosis correctness is the syndrome dependent bound T, with T T, asserted by the diagnosis algorithm itself for every given diagnosis experiment. Simulation studies provided evidence that the diagnosis is complete or almost complete if the number of faults is below T. The fraction of units which cannot be identified as either faulty or nonfaulty remains relatively small as long as the number of faults is below n=3 and, as long as the number of faults is below n=2, the diagnosis is correct with high probability.Source: I.E.E.E. TRANSACTIONS ON COMPUTERS (PRINT), vol. 50 (issue 10), pp. 1095-1102
Chessa S, Maestrini P
A new diagnosis algorithm for square grids is introduced. The algorithm always provides correct diagnosis if the number of faulty processors is below T, a bound with T 2 ...n2=3+, which was derived by worst-case analysis. A more effective tool to validate the diagnosis correctness is the syndrome dependent bound T, with T T, asserted by the diagnosis algorithm itself for every given diagnosis experiment. Simulation studies provided evidence that the diagnosis is complete or almost complete if the number of faults is below T. The fraction of units which cannot be identified as either faulty or nonfaulty remains relatively small as long as the number of faults is below n=3 and, as long as the number of faults is below n=2, the diagnosis is correct with high probability.Source: I.E.E.E. TRANSACTIONS ON COMPUTERS (PRINT), vol. 50 (issue 10), pp. 1095-1102
2007
Journal article
Open Access
Worst-case diagnosis completeness in regular graphs under the PMC model
Caruso A, Chessa S, Maestrini P
System-level diagnosis aims at the identification of faulty units in a system by the analysis of the system syndrome, that is, the outcomes of a set of interunit tests. For any given syndrome, it is possible to produce a correct (although possibly incomplete) diagnosis of the system if the number of faults is below a syndrome-dependent bound and the degree of diagnosis completeness, that is, the number of correctly diagnosed units, is also dependent on the actual syndrome . The worst-case diagnosis completeness is a syndrome-independent bound that represents the minimum number of units that the diagnosis algorithm correctly diagnoses for any syndrome. This paper provides a lower bound to the worst-case diagnosis completeness for regular graphs for which vertexisoperimetric inequalities are known and it shows how this bound can be applied to toroidal grids. These results prove a previous hypothesis about the influence of two topological parameters of the diagnostic graph, that is, the bisection width and the diameter, on the degree of diagnosis completenessSource: I.E.E.E. TRANSACTIONS ON COMPUTERS (PRINT), vol. 56 (issue 7), pp. 917-924
DOI: 10.1109/tc.2007.1052
Metrics:
Caruso A, Chessa S, Maestrini P
System-level diagnosis aims at the identification of faulty units in a system by the analysis of the system syndrome, that is, the outcomes of a set of interunit tests. For any given syndrome, it is possible to produce a correct (although possibly incomplete) diagnosis of the system if the number of faults is below a syndrome-dependent bound and the degree of diagnosis completeness, that is, the number of correctly diagnosed units, is also dependent on the actual syndrome . The worst-case diagnosis completeness is a syndrome-independent bound that represents the minimum number of units that the diagnosis algorithm correctly diagnoses for any syndrome. This paper provides a lower bound to the worst-case diagnosis completeness for regular graphs for which vertexisoperimetric inequalities are known and it shows how this bound can be applied to toroidal grids. These results prove a previous hypothesis about the influence of two topological parameters of the diagnostic graph, that is, the bisection width and the diameter, on the degree of diagnosis completenessSource: I.E.E.E. TRANSACTIONS ON COMPUTERS (PRINT), vol. 56 (issue 7), pp. 917-924
DOI: 10.1109/tc.2007.1052
Metrics:
See at:
Archivio Istituzionale della Ricerca- Università del Salento 
| IEEE Transactions on Computers | CNR IRIS | CNR IRIS
2006
Journal article
Restricted
Reliable routing in wireless ad hoc networks : the virtual routing protocol
Albini Lc, Caruso A, Chessa S, Maestrini P
Anovel routing protocol for wireless, mobile ad hoc networks is presented.This protocol incorporates features that enhance routing reliability, defined as the ability to provide almost 100% packet delivery rate. The protocol is based on a virtual structure, unrelated to the physical network topology,where mobile nodes are connected by virtual links and are responsible for keeping physical routes to their neighbors in the virtual structure. Routes between pairs of mobiles are set up by using information to translate virtual paths discovered in the virtual structure. Route discovery and maintenance phases of the protocol are based on unicast messages travelling across virtual paths, with sporadic use of flooding protocol.Most flooding is executed in the background using low priority messages. The routing protocol has been evaluated and compared with the Dynamic Source Routing protocol and with the Zone Routing Protocol by means of simulation.Source: JOURNAL OF NETWORK AND SYSTEMS MANAGEMENT, vol. 14, pp. 335-358
Albini Lc, Caruso A, Chessa S, Maestrini P
Anovel routing protocol for wireless, mobile ad hoc networks is presented.This protocol incorporates features that enhance routing reliability, defined as the ability to provide almost 100% packet delivery rate. The protocol is based on a virtual structure, unrelated to the physical network topology,where mobile nodes are connected by virtual links and are responsible for keeping physical routes to their neighbors in the virtual structure. Routes between pairs of mobiles are set up by using information to translate virtual paths discovered in the virtual structure. Route discovery and maintenance phases of the protocol are based on unicast messages travelling across virtual paths, with sporadic use of flooding protocol.Most flooding is executed in the background using low priority messages. The routing protocol has been evaluated and compared with the Dynamic Source Routing protocol and with the Zone Routing Protocol by means of simulation.Source: JOURNAL OF NETWORK AND SYSTEMS MANAGEMENT, vol. 14, pp. 335-358
2010
Journal article
Restricted
The effects of weather on the life time of wireless sensor networks using FSO/RF communication
Chessa S, Leitgeb E, Nadeem F, Zaman S
The increased interest in long lasting wireless sensor networks motivates to use Free Space Optics (FSO) link along with radio frequency (RF) link for communication. Earlier results show that RF/FSO wireless sensor networks have life time twice as long as RF only wireless sensor networks. However, for terrestrial applications, the effect of weather conditions such as fog, rain or snow on optical wireless communication link is major concern, that should be taken into account in the performance analysis. In this paper, life time performance of hybrid wireless sensor networks is compared to wireless sensor networks using RF only for terrestrial applications and weather effects of fog, rain and snow. The results show that combined hybrid network with three threshold scheme can provide efficient power consumption of 6548 seconds, 2118 seconds and 360 seconds for measured fog, snow and rain events respectively resulting in approximately twice of the life time with only RF link.Source: RADIOENGINEERING, vol. 19, pp. 262-270
Chessa S, Leitgeb E, Nadeem F, Zaman S
The increased interest in long lasting wireless sensor networks motivates to use Free Space Optics (FSO) link along with radio frequency (RF) link for communication. Earlier results show that RF/FSO wireless sensor networks have life time twice as long as RF only wireless sensor networks. However, for terrestrial applications, the effect of weather conditions such as fog, rain or snow on optical wireless communication link is major concern, that should be taken into account in the performance analysis. In this paper, life time performance of hybrid wireless sensor networks is compared to wireless sensor networks using RF only for terrestrial applications and weather effects of fog, rain and snow. The results show that combined hybrid network with three threshold scheme can provide efficient power consumption of 6548 seconds, 2118 seconds and 360 seconds for measured fog, snow and rain events respectively resulting in approximately twice of the life time with only RF link.Source: RADIOENGINEERING, vol. 19, pp. 262-270
2006
Journal article
Restricted
Bounds on hop distance in greedy routing approach in wireless ad hoc networks
De S, Caruso A, Chaira T, Chessa S
Wireless ad hoc networks are generally characterised by random node locations and multi-hop routes. A quantitative knowledge of the relation between hop count and Euclidean distance could provide a better understanding of important network parameters such as end-to-end delay, power consumption along the route, and node localisation. In this paper, we present an analytic approach to capture the statistics on hop count for a given source-to-destination Euclidean distance in a greedy routing approach. We also show that, for a given hop count, the bounds on Euclidean distance can be computed from the distribution characteristics of per-hop progress.Source: INTERNATIONAL JOURNAL OF WIRELESS AND MOBILE COMPUTING, vol. 14, pp. 131-140
De S, Caruso A, Chaira T, Chessa S
Wireless ad hoc networks are generally characterised by random node locations and multi-hop routes. A quantitative knowledge of the relation between hop count and Euclidean distance could provide a better understanding of important network parameters such as end-to-end delay, power consumption along the route, and node localisation. In this paper, we present an analytic approach to capture the statistics on hop count for a given source-to-destination Euclidean distance in a greedy routing approach. We also show that, for a given hop count, the bounds on Euclidean distance can be computed from the distribution characteristics of per-hop progress.Source: INTERNATIONAL JOURNAL OF WIRELESS AND MOBILE COMPUTING, vol. 14, pp. 131-140
2009
Journal article
Restricted
A model with applications for data survivability in critical infrastructures
Albano M, Chessa S, Di Pietro R
Information assurance in Critical Infrastructures (CIs) is a problem of great practical interest and a challeng- ing research field. Within this scope we focus on the problem of monitoring of CIs. In particular, we propose a model to max- imize the amount of monitoring-related data that can survive after a portion of the CI suffers a disaster. The proposed model addresses a specific CI-oil pipelines-, and it is built on the hypothesis that the monitoring data are provided by means of wireless sensor networks. In particular, we consider a CI where the sensors are deployed along the pipelines and execute a com- mon monitoring task with a given sampling rate. In order to ensure data availability the sensors replicate the sensed data to their peers. This model poses a few unique challenges, calling for the optimization of competing system parameters. For in- stance, a higher sampling rate would allow, on one hand, a finer- grain analysis of the situation while on the other hand would consume more energy. High volume of data replication would allow a higher chance for data to survive a disaster-hence help- ing in forensics or further disaster prevention-, while it would cost more in both energetic and bandwidth terms. We derive an analytical model for this scenario. This model can be processed to derive the optimal sampling rate that maximizes the amount of information collected by the monitoring infras- tructure, while satisfying the complex and competing system parameters. Further, simulations are performed on both reg- ular (tree-based) and random generated oil pipelines and show the wide applicability of our model, as well as providing a few non-intuitive results on the behaviour of the competing system parameters. Finally, we develop a case study on a real-world oil pipeline. Results support the quality of the proposed model and its flexibility.
Albano M, Chessa S, Di Pietro R
Information assurance in Critical Infrastructures (CIs) is a problem of great practical interest and a challeng- ing research field. Within this scope we focus on the problem of monitoring of CIs. In particular, we propose a model to max- imize the amount of monitoring-related data that can survive after a portion of the CI suffers a disaster. The proposed model addresses a specific CI-oil pipelines-, and it is built on the hypothesis that the monitoring data are provided by means of wireless sensor networks. In particular, we consider a CI where the sensors are deployed along the pipelines and execute a com- mon monitoring task with a given sampling rate. In order to ensure data availability the sensors replicate the sensed data to their peers. This model poses a few unique challenges, calling for the optimization of competing system parameters. For in- stance, a higher sampling rate would allow, on one hand, a finer- grain analysis of the situation while on the other hand would consume more energy. High volume of data replication would allow a higher chance for data to survive a disaster-hence help- ing in forensics or further disaster prevention-, while it would cost more in both energetic and bandwidth terms. We derive an analytical model for this scenario. This model can be processed to derive the optimal sampling rate that maximizes the amount of information collected by the monitoring infras- tructure, while satisfying the complex and competing system parameters. Further, simulations are performed on both reg- ular (tree-based) and random generated oil pipelines and show the wide applicability of our model, as well as providing a few non-intuitive results on the behaviour of the competing system parameters. Finally, we develop a case study on a real-world oil pipeline. Results support the quality of the proposed model and its flexibility.
2003
Conference article
Restricted
Dependable and Secure Data Storage and Retrieval in Mobile, Wireless Networks
Chessa S, Maestrini P
This paper introduces a distributed data storage for mobile, wireless networks based on a peer-to-peer paradigm. The distributed storage provides support to create and share files under a write-once model, and ensures at the same time data confidentiality and dependability by encoding files in a Redundant Residue Number System. More specifically files are partitioned into records and each record in encoded separately as (h+r)-tuples of data residues using h+r moduli. In turn, the residues are distributed among the mobiles in the network. Dependability is ensured since data can be reconstructed in the presence of up to s£r residue erasures, combined with up to corrupted residues, and data confidentiality is ensured since recovering the original information requires knowledge of the entire set of moduli.
Chessa S, Maestrini P
This paper introduces a distributed data storage for mobile, wireless networks based on a peer-to-peer paradigm. The distributed storage provides support to create and share files under a write-once model, and ensures at the same time data confidentiality and dependability by encoding files in a Redundant Residue Number System. More specifically files are partitioned into records and each record in encoded separately as (h+r)-tuples of data residues using h+r moduli. In turn, the residues are distributed among the mobiles in the network. Dependability is ensured since data can be reconstructed in the presence of up to s£r residue erasures, combined with up to corrupted residues, and data confidentiality is ensured since recovering the original information requires knowledge of the entire set of moduli.
2005
Conference article
Restricted
Computationally, memory and bandwidth efficient distillation codes to mitigate DoS in multicast
Di Pietro R, Chessa S, Maestrini P
In this paper we address the problem of Denial of Service (DoS) mitigation in multicast environment. The contribution of the paper is twofold: first, we introduce an optimization (PMT) on the Merkle tree distillation codes by leveraging the implicit redundancy of a Merkle tree representation. Second, we devise a new algorithm (CECInA) for encoding/decoding that mitigates DoS attacks on the end user device and reduces the buffer size in case of DoS. In particular, according to the type of DoS attack, CECInA achieves either complexity or buffering savings. This attack mitigation capability is not a feature offered by state of the art algorithms. Furthermore CECInA is particularly efficient when used in conjunction with PMT. We derive and plot analytical results that indicates that the proposed solutions are effective. Hence, CECInA can be a viable solution to mitigate DoS in multicast, particularly suited for contexts in which end-user devices are resource constrained. As for PMT, note that it is a general technique that can be adopted independently from CECInA.
Di Pietro R, Chessa S, Maestrini P
In this paper we address the problem of Denial of Service (DoS) mitigation in multicast environment. The contribution of the paper is twofold: first, we introduce an optimization (PMT) on the Merkle tree distillation codes by leveraging the implicit redundancy of a Merkle tree representation. Second, we devise a new algorithm (CECInA) for encoding/decoding that mitigates DoS attacks on the end user device and reduces the buffer size in case of DoS. In particular, according to the type of DoS attack, CECInA achieves either complexity or buffering savings. This attack mitigation capability is not a feature offered by state of the art algorithms. Furthermore CECInA is particularly efficient when used in conjunction with PMT. We derive and plot analytical results that indicates that the proposed solutions are effective. Hence, CECInA can be a viable solution to mitigate DoS in multicast, particularly suited for contexts in which end-user devices are resource constrained. As for PMT, note that it is a general technique that can be adopted independently from CECInA.
2005
Conference article
Open Access
GPS free coordinate assignment and routing in wireless sensor networks
Caruso A, Chessa S, Swades D, Urpi A
In this paper we consider the problem of constructing a coordinate system in a sensor network where location information is not available. To this purpose we introduce the Virtual Coordinate assignment protocol (VCap) which defines a virtual coordinate system based on hop distances. As compared to other approaches, VCap is simple and have very little requirements in terms of communication and memory overheads. We compare by simulations the performances of greedy routing using our virtual coordinate system with the one using the physical coordinates. Results show that the virtual coordinate system can be used to efficiently support geographic routingDOI: 10.1109/infcom.2005.1497887
Metrics:
Caruso A, Chessa S, Swades D, Urpi A
In this paper we consider the problem of constructing a coordinate system in a sensor network where location information is not available. To this purpose we introduce the Virtual Coordinate assignment protocol (VCap) which defines a virtual coordinate system based on hop distances. As compared to other approaches, VCap is simple and have very little requirements in terms of communication and memory overheads. We compare by simulations the performances of greedy routing using our virtual coordinate system with the one using the physical coordinates. Results show that the virtual coordinate system can be used to efficiently support geographic routingDOI: 10.1109/infcom.2005.1497887
Metrics:
See at:
Archivio Istituzionale della Ricerca- Università del Salento | www.comp.nus.edu.sg | doi.org | CNR IRIS | ieeexplore.ieee.org | CNR IRIS | www.scopus.com
2006
Conference article
Restricted
The localized vehicular multicast middleware : a framework for ad hoc inter-vehicles multicast communications
Barsotti F, Caruso A, Chessa S
This paper defines a novel semantic for multicast in vehicular ad hoc networks (VANETs) and it defines a middleware, the Localized Vehicular Multicast Middleware (LVMM) that enables minimum cost, source-based multicast communications in VANETs. The middleware provides support to find vehicles suitable to sustain multicast communications, to maintain multicast groups, and to execute a multicast routing protocol, the Vehicular Multicast Routing Protocol (VMRP), that delivers messages of multicast applications to all the recipients utilizing a loop-free, minimum cost path from each source to all the recipients. LVMM does not require a vehicle to know all other members: only knowledge of directly reachable nodes is required to perform the source-based rout
Barsotti F, Caruso A, Chessa S
This paper defines a novel semantic for multicast in vehicular ad hoc networks (VANETs) and it defines a middleware, the Localized Vehicular Multicast Middleware (LVMM) that enables minimum cost, source-based multicast communications in VANETs. The middleware provides support to find vehicles suitable to sustain multicast communications, to maintain multicast groups, and to execute a multicast routing protocol, the Vehicular Multicast Routing Protocol (VMRP), that delivers messages of multicast applications to all the recipients utilizing a loop-free, minimum cost path from each source to all the recipients. LVMM does not require a vehicle to know all other members: only knowledge of directly reachable nodes is required to perform the source-based rout
2007
Conference article
Restricted
Q-NIGHT: adding QoS to data centric storage in non-uniform sensor networks
Albano M, Chessa S, Nidito F, Pelagatti S
Storage of sensed data in wireless sensor networks is essential when the sink node is unavailable due to fail- ure and/or disconnections, but it can also provide efficient access to sensed data to multiple sink nodes. Recent ap- proaches to data storage rely on Geographic Hash Tables for efficient data storage and retrieval. These approaches however do not support different QoS levels for different classes of data as the programmer has no control on the level of redundancy of data. They result in a great unbal- ance in the storage usage in each sensor, even when sen- sors are uniformly distributed. This may cause serious data losses, waste energy and shorten the overall lifetime of the sensornet. In this paper, we propose a novel protocol, Q- NiGHT, which (1) provides a direct control on the level of QoS in the data dependability, and (2) uses a strategy sim- ilar to the rejection method to build a hash function which scatters data approximately with the same distribution of sensors. The benefits of Q-NiGHT are assessed through a detailed simulation experiment, also discussed in the paper. Results show its good performance on different sensors dis- tributions on terms of both protocol costs and load balance between sensors.
Albano M, Chessa S, Nidito F, Pelagatti S
Storage of sensed data in wireless sensor networks is essential when the sink node is unavailable due to fail- ure and/or disconnections, but it can also provide efficient access to sensed data to multiple sink nodes. Recent ap- proaches to data storage rely on Geographic Hash Tables for efficient data storage and retrieval. These approaches however do not support different QoS levels for different classes of data as the programmer has no control on the level of redundancy of data. They result in a great unbal- ance in the storage usage in each sensor, even when sen- sors are uniformly distributed. This may cause serious data losses, waste energy and shorten the overall lifetime of the sensornet. In this paper, we propose a novel protocol, Q- NiGHT, which (1) provides a direct control on the level of QoS in the data dependability, and (2) uses a strategy sim- ilar to the rejection method to build a hash function which scatters data approximately with the same distribution of sensors. The benefits of Q-NiGHT are assessed through a detailed simulation experiment, also discussed in the paper. Results show its good performance on different sensors dis- tributions on terms of both protocol costs and load balance between sensors.
2007
Conference article
Restricted
Virtual naming and geographic routing on wireless sensor networks
Filardi N, Caruso A, Chessa S
We consider the problem of routing with guaranteed de- livery in wireless sensor networks where physical locations of the sensors are not known. We propose a naming proto- col which defines a 2-dimensional coordinate system and a routing protocol (Ibrid) which ensures guaranteed delivery of packets. We show by means of simulation that in realis- tic settings where the network includes voids and obstacles, Ibrid finds routess hortest than those obtained with existing geographic routing algorithms over physical coordinates.DOI: 10.1109/iscc.2007.4381526
Metrics:
Filardi N, Caruso A, Chessa S
We consider the problem of routing with guaranteed de- livery in wireless sensor networks where physical locations of the sensors are not known. We propose a naming proto- col which defines a 2-dimensional coordinate system and a routing protocol (Ibrid) which ensures guaranteed delivery of packets. We show by means of simulation that in realis- tic settings where the network includes voids and obstacles, Ibrid finds routess hortest than those obtained with existing geographic routing algorithms over physical coordinates.DOI: 10.1109/iscc.2007.4381526
Metrics:
See at:
doi.org | CNR IRIS | CNR IRIS | iris.unisalento.it
2007
Conference article
Restricted
Embedding source signature in multicast wireless video streams
Chessa S, Giunta G, Oligeri G
We consider the problem of source authentication of video streams in multicast environments. We proposed a novel algorithm which combines signature amortization based on hash chains and watermarking to embed hash chains in the video stream. The algorithm exploits a novel watermarking procedure using Reed-Solomon mark encoding which ensures error-free and fast convergence mark extraction. We show that the algorithm has a negligible impact on the video stream quality and we evaluate the configuration parameters of the algorithm which ensure proper verification of the source authenticity.DOI: 10.1109/wowmom.2007.4351719
Metrics:
Chessa S, Giunta G, Oligeri G
We consider the problem of source authentication of video streams in multicast environments. We proposed a novel algorithm which combines signature amortization based on hash chains and watermarking to embed hash chains in the video stream. The algorithm exploits a novel watermarking procedure using Reed-Solomon mark encoding which ensures error-free and fast convergence mark extraction. We show that the algorithm has a negligible impact on the video stream quality and we evaluate the configuration parameters of the algorithm which ensure proper verification of the source authenticity.DOI: 10.1109/wowmom.2007.4351719
Metrics:
2008
Conference article
Open Access
Information assurance in critical infrastructures via wireless sensor networks
Albano M, Chessa S, Di Pietro R
Information assurance in critical infrastructure is an is- sue that has been addressed generally focusing on real-time or quasi real-time monitoring of the critical infrastructure; so that action could be undertaken when anomalies arise, to avoid more severe consequences to the infrastructure. In this paper, we relax the hypothesis of intervening when anomalies are detected: we focus on sensed data surviv- ability. Specifically, we study this problem in a specific crit- ical infrastructure: pipelines. The problem we introduce is how to place sensors in such a way that the sensed data re- lated to the monitoring of the pipeline will survive even in presence of a partial destruction of the infrastructure. The contributions of this paper are twofold. First, we in- troduce the problem of sensed data survivability in critical infrastructure. In this framework, the goal is to have the sensed data to survive to the infrastructure failure, so that the phenomena that lead to the failure could be better un- derstood and possibly tackled in similar deployment. Sec- ond, we provide a model that allows to produce an optimal network topology with respect to the level of information assurance desired, while satisfying deployment constraints, such as available bandwidth and available energy of the sensors. We believe that the work addressed in this paper could foster further research in the field of information as- surance in critical infrastructure.DOI: 10.1109/ias.2008.54
Metrics:
Albano M, Chessa S, Di Pietro R
Information assurance in critical infrastructure is an is- sue that has been addressed generally focusing on real-time or quasi real-time monitoring of the critical infrastructure; so that action could be undertaken when anomalies arise, to avoid more severe consequences to the infrastructure. In this paper, we relax the hypothesis of intervening when anomalies are detected: we focus on sensed data surviv- ability. Specifically, we study this problem in a specific crit- ical infrastructure: pipelines. The problem we introduce is how to place sensors in such a way that the sensed data re- lated to the monitoring of the pipeline will survive even in presence of a partial destruction of the infrastructure. The contributions of this paper are twofold. First, we in- troduce the problem of sensed data survivability in critical infrastructure. In this framework, the goal is to have the sensed data to survive to the infrastructure failure, so that the phenomena that lead to the failure could be better un- derstood and possibly tackled in similar deployment. Sec- ond, we provide a model that allows to produce an optimal network topology with respect to the level of information assurance desired, while satisfying deployment constraints, such as available bandwidth and available energy of the sensors. We believe that the work addressed in this paper could foster further research in the field of information as- surance in critical infrastructure.DOI: 10.1109/ias.2008.54
Metrics:
See at:
vneumann.etse.urv.es | doi.org | CNR IRIS | ieeexplore.ieee.org | CNR IRIS
2008
Conference article
Restricted
Virtual structure effects in two hybrid routing protocols for ad hoc networks
Pessoa Albini L C, Brawerman A, Nogueira Lima M, Chessa S, Maestrini P
The Virtual Routing Protocol and the Virtual Dis- tance Vector are hybrid routing protocols for mobile ad hoc networks which are based on virtual structures. Virtual structures are unrelated to the physical network topology and units are responsible for keeping physical routes to their neighbors in the virtual structure. The protocols were designed to work with different virtual structures, like: Rings of Rings RoR, hypercube, CCC and 3D-torus. This paper compares simulation results of these four different virtual structures. It will be shown through simulation results that the protocols are, to some extent, independent of the graph implementing the virtual structure.DOI: 10.1109/iswpc.2008.4556245
Metrics:
Pessoa Albini L C, Brawerman A, Nogueira Lima M, Chessa S, Maestrini P
The Virtual Routing Protocol and the Virtual Dis- tance Vector are hybrid routing protocols for mobile ad hoc networks which are based on virtual structures. Virtual structures are unrelated to the physical network topology and units are responsible for keeping physical routes to their neighbors in the virtual structure. The protocols were designed to work with different virtual structures, like: Rings of Rings RoR, hypercube, CCC and 3D-torus. This paper compares simulation results of these four different virtual structures. It will be shown through simulation results that the protocols are, to some extent, independent of the graph implementing the virtual structure.DOI: 10.1109/iswpc.2008.4556245
Metrics:
See at:
doi.org | CNR IRIS | ieeexplore.ieee.org | CNR IRIS