University of Pisa and Scuola Superiore Sant’Anna

Corso di Laurea Magistrale in Informatica e Networking Master Program in Computer Science and Networking

MASTER THESIS PROPOSALS This documents contains proposals of Master Thesis in Computer Science and Networking. Most of them are mainly descriptions of research or application areas. Thus, it is possible that some issues have been already chosen in the past, but could still be available. Students are invited to contact the supervisors directly.

Paolo Ferragina

Energy-aware computing

In a recent study we have proposed a new methodology to estimate the energy consumption of an

algorithm, and we have successfully validated it on several simple algorithms and architectures. This

is a key issue nowadays because “the cost of power and cooling is likely to exceed that of hardware”

[Google, 2007]. The main goal of this master thesis is therefore to deepen the study onto this

methodology by analyzing more sophisticated algorithms that process large datasets and thus work

on many memory levels. This study will also investigate the impact that Solid-State disks and GPUs

can have in the design of those algorithms and in their energy-profile.

Fabrizio Di Pasquale, Marco Vanneschi

FPGA-based Implementation of Pulse Coding Techniques for Distributed Optical Fiber Sensors

This thesis will be mainly focused on software implementation of pulse coding techniques, actually

Simplex coding, in order to improve the performance of distributed optical fiber sensors.

Optical fiber sensors are attracting a significant interest for their many fields of applications, ranging

from civil and geo-technical engineering to the oil & gas industry, from energy management to

railway, highway and structural health monitoring. The use of optical pulse coding techniques allows

one to extend the sensing range of the sensors while keeping meter or sub-meter scale spatial

resolutions.

In order to boost the performance of pulse coding in real applications, coding and decoding

algorithms must be carefully designed implemented, optimizing required resource allocation and

minimizing processing overheads which could potentially cancel out the provided signal-to-noise

ratio enhancement.

To this end this thesis will address the study, development and implementation of coding algorithms,

for instance Simplex coding, on an FPGA-based architecture aimed at laser triggering.

During the design stage, accurate algorithm optimization and performance simulation steps are

critical points due to the limited available resources in the FPGA together with the high expected

processing rate for the coded pulse generation (exceeding 100 MHz).

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Fabrizio Di Pasquale, Marco Vanneschi

Multi-Core Approach for Real-Time Decoding in Optical Fiber Sensor Systems

This thesis will deal with the development, testing and subsequent implementation of a decoding

algorithm under a multi-core architecture to provide real-time detection capabilities applied to a

optical fiber sensing system.

Optical fiber sensors are attracting a significant interest for their many fields of applications, ranging

from civil and geo-technical engineering to the oil & gas industry, from energy management to

railway, highway and structural health monitoring. The use of optical pulse coding techniques allows

one to extend the sensing range of the sensors while keeping meter or sub-meter scale spatial

resolutions.

In optical fiber sensor systems employing optical pulse coding, the decoding process applied to

coded traces constitutes a fundamental step in the reconstruction of the physical fiber parameters,

and is critical in providing real-time sensing capabilities. The ideal decoding process typically

involves application of different linear-algebra operations (such as matrix inversions, scalar products

and so forth) on a large data stream resulting from analog-to-digital sampling within stringent

temporal constraints (typically a fraction of second) and with limited available computational

resources. Presently, due to the amount of involved calculations in decoding, the large processing

time (> 20 sec) hinders an acceptable sensing performance. In this context, the thesis will be aimed at

developing and testing a decoding algorithm (based for instance on Simplex codes) under a multi-

core processor architecture, enabling msec-order data throughput and real-time sensing capabilities.

Marco Vanneschi, Piero Castoldi

On-chip optical interconnection structures for multi/manycore architectures

The rapid development of multi/manycore technologies offers the opportunity for highly parallel

architectures implemented on a single chip. While the first, low-parallelism multicore products have

been based on simple interconnection structures (single bus, very simple crossbar), the emerging

highly parallel architectures will require complex, limited-degree interconnection networks. This

thesis studies this trend according to the general theory of interconnection structures for parallel

machines, and investigates some solutions in terms of performance, cost, fault-tolerance, and run-

time support to shared-memory and/or message passing programming mechanisms.

Marco Vanneschi, Stefano Giordano

Computational and Cost Model for High-performance Pervasive Computing

High-performance Pervasive Computing is a new paradigm aiming to exploit the potentials of

heterogeneous, ubiquitous and mobile computing and communication infrastructures in order to

achieve high-performance especially for real-time, critical applications, e.g. emergency management,

homeland security.

We consider distributed platforms characterized by general-purpose processing nodes (e.g. servers,

clouds), but also specialized/embedded processing nodes (e.g. wearable devices, sensors, smart-

phones), and different heterogeneous wired and/or wireless networks. All these resources, even those

apparently (till yesterday) limited in processing power and capacity, are used to actively take part to

the distributed high-performance computation.

The computational model provides mechanisms for the explicit definition of the application control

logic, that decides and manages adaptive reconfigurations in response to various events. An

associated cost model is defined to formalize and carry out the most suitable control strategies for

achieving the desired QoS level (e.g. response time, energy saving, precision of computed results,

and other execution metrics and their proper combinations).

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The applications feature the full integration of communication and processing aspects, in such a way

as to overcome the classical “black-box” or “best-effort” approach in which the two layers are

characterized by specific and independent control actions concerning only their local information.

The integrated approach to autonomic applications is an unavoidable feature in order to target the

desired QoS levels both for high-performance distributed processing and information flows.

This thesis investigates and experiments a version of the computational and cost model for the most

critical mechanisms on real-life high-performance pervasive applications.

Marco Vanneschi

High-performance implementation of signal processing applications for multicore architectures - in collaboration with SELEX SISTEMI INTEGRATI, Rome

In the context of research programmes and University of Pisa – Selex SI collaborations, this thesis

deals with the efficient and scalable implementations of the most critical parts of signal processing

applications, especially in radar environments. Parallel versions of numerical and non-numerical

algorithms, for which high-performance and real-time requirements are a must, are investigated,

implemented according to the parallel programming models of the research group, and evaluated.

Complex real-life applications, consisting in the integration of several algorithmic modules, are

studied and evaluated.

Marco Vanneschi

Theses on high-performance systems and tools for advance financial processing at GBG Lab

in collaboration with LIST SpA – GBG Lab, Pisa

Data Stream Processing and Complex Event Processing are general computational paradigms

characterizing advanced financial processing applications (brokerage, market-making, algo-trading,

financial markets products). From a modeling viewpoint, these paradigms consider stream-based

computations in which complex patterns of data and events are processed on-line and “on the fly”

(i.e. information are not present in persistent data structures, instead they flow in continuous

streams). New areas of research are stimulated by this paradigm, including algorithms, parallel

models and fault tolerence. In GBG Lab we are working in new high-performance systems and tools

for Data Stream Processing and Complex Event Processing, exploiting all the current and future

technologies for multi-/many-core components.

A series of theses are available at GBG Lab on these topics.

Marco Vanneschi, Marco Danelutto

Parallel programming model and cost model for shared-memory multicore architectures

One of the main trend in multi/manycore technology consists in highly-parallel on-chip architectures

with shared memory and complex memory hierarchies. The efficient exploitation of such

architectures requires the ability to define an accurate cost model for the architecture, in particular

for the caching hierarchies. Based on this cost model, a high-level parallel programming model

should be able to effectively deal with the shared memory paradigm at low overhead. This thesis

investigates these problems starting from the group experiences on high-level parallel programming,

and taking into account existing shared memory multicore products and their trends.

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Marco Vanneschi, Marco Danelutto

New programming model for highly-parallel architectures including GPU subsystems

Though GPUs have recently received some attention in high-performance applications, the

programmability of systems including GPU SIMD coprocessors and SISD/MIMD architectures is

largely an open research and technological problems. Typical issues are the high-level view of the

different architectural style, and the load balancing and communication optimization problems. This

thesis investigates and experiments solutions to the parallel programming models starting from the

group experiences on high-level parallel programming, and taking into account existing GPU

products and their trends.

Marco Danelutto

Autonomic management of structured parallel computations

Behavioural skeletons have been introduced some years ago to study possibilities offered by co-

design of parallelism exploitation patterns and non functional concern autonomic management in

component frameworks. The main goal of this thesis is to investigate the feasibility of the usage of

behavioural skeletons in the field of high performance network processing. In particular, we want to

investigate suitable reactive and proactive policies suitable to handle typical hot spots in network

management which are related to peaks in the (monitored/managed) network traffic. The thesis may

involve work on the Behavioural skeletons prototypes currently available.

Marco Danelutto

Macro data flow computing models for multi/many cores

Data flow has been considered as a viable computing model to support efficient execution of highly

parallel computations since the ‘80. The research on data flow architectures did not survive the

impressive development achieved in commodity processors. We propose to investigate the

possibility to implement macro data flow interpreters targeting currently available multicores via

FastFlow, the fine grain parallel library developed at the Pisa and Torino Dept. of Computer Science.

The candidate will develop simple prototypes supporting macro data flow computations and will

then evaluate alternative implementation mechanisms and policies. “Embedded” fault tolerance will

be considered a primary non functional concern. The possibility to use different “task parallel”

libraries, such as openMP or TBB will be considered, in case FastFlow fails supporting macro data

flow for some reason.

Nicola Tonellotto

Multi-criteria Job Scheduling for Cloud Computing Platforms

This thesis aims at designing and evaluating a multi-criteria job scheduling policy for scheduling a

continuous stream of batch jobs on large-scale cloud computing platforms. The scheduling policy

will have as objective to meet a set of Quality of Service (QoS) requirements requested by both the

submitted jobs and installations (providers). Typical QoS requirements are the time at which user

wants to receive results and to optimize the exploitation of hardware and software resources.

Nicola Tonellotto

Landmark Recognition via Parallel Clustering

The goal of this thesis is to design and implement solutions to recognize the most visited places (i.e.

landmarks) of a city given a collectionof photos that were shot by tourists visiting that city. This can

be achieved by clustering those photos, i.e. grouping similar ones together, on the basis of their

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visual descriptors. The expected outcome of this thesis, is to provided a parallel software (e.g.

exploiting map-reduce) that translates a set of user photos in a sequence of visited landmarks.

Nicola Tonellotto, Marco Danelutto

Managing Terabytes using Algorithmic Skeletons

The aim of this thesis is to design and evalute algorithms index huge amounts of data exploiting

technologies beyond the MapReduce approach. This study will be devoted to analyse existing

algorithms and implement new solution exploiting cloud- and skeleton-base technologies

implemented in Java.

Nicola Tonellotto, Stefano Giordano

Performance Analysis of Reliable Multicast Delivery in Mobile Clouds

The aim of this thesis is evaluating the performance of reliable multicast file delivery in the next-

generation mobile cloud scenarios. This study will be devoted to design and implement a simulator

for reliable multicast protocols (e.g. NORM) in C++, taking into account the distruptive paradigm in

land mobile computer networks.

Nicola Tonellotto, Stefano Giordano

Traffic Scheduler for Private/Public Communications in Clouds

The aim of this thesis is to design a traffic scheduler for flow control of multicast and unicast

delivery of data, in batch and stream mode. This study will include the analysis of existing solutions

for the dissemination of private data in distributed environments, the design of a solution supporting

multicast delivery of data in these environments and a proof-of-concept implementation and

evaluation.

Linda Pagli

Distributed maintenance of a Spanning Tree

Low cost and high reliability of a network are conflicting parameters. Network survivability can be strengthened by increasing connectivity, but this also increases the network cost. We know that the network with minimum cost is a spanning tree of the network graph, but such a network will not even survive to a single edge failure, hence to enhance survivability some redundancy must be introduced. The problem of spanning tree maintenance in presence of faults in a distributed environment using only local knowledge will be considered. Starting from 1-fault tolerant spanning tree known solutions, we want to develop distributed efficient protocols able to maintain the spanning tree in presence of k –1 consecutive failures, with minimal extra storage.

Giuseppe Attardi

Audio Graffiti

Social services that allow people to share information are gaining great popularity. Adding

localization to these services allows providing access to information of interest which is dependent

on the user location. The goal of this master thesis is to participate in the design and development of

Audio Graffiti, a service for sharing audio messages created on mobile devices which are virtually

placed next to monuments in the city of Florence. The project is funded by the Comune di Firenze

and will exploit a wireless infrastructure being built by the municipality. Several aspects will be

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addressed, including developing an iPhone app to access to the service, novel localization

techniques, a distributed system for data collection and transmission and anti-spam techniques.

Piero Castoldi, Isabella Cerutti, Nicola Andriolli

Architetture e scheduling a basso consumo di energia negli optical interconnect/switch

While energy efficiency has been one of the main design requirements in battery-run mobile computers, the non-portable devices and their interconnection have been exempted from this requirement so far. Indeed, the ultimate goal of interconnection networks has always been low latency and high throughput. Unfortunately, electronic interconnection networks drain a considerable amount of power at peak utilization, while large amount of power is wasted at low utilization level. Optical communications already demonstrated its capability for ultra-high transmission, this thesis targets the design of a scalable optical interconnection architectures able to achieve both a high throughput at peak utilization and a low-power consumption compared to the utilization.

Piero Castoldi, Isabella Cerutti, Marco Di Natale

Applicazioni delle tecnologie di telecomunicazione e delle tecnologie informatiche alla rete di distribuzione elettrica (smart grid) in ambito domestico o veicolare.

The next-generation electricity grid, known as the “smart grid” or “intelligent grid” is expected to address the major shortcomings of the existing grid. In essence, the smart grid needs to provide the electricity company with full visibility and pervasive control over their assets and services. To allow this communication and data management play an important role for balancing and managing energy production, consumption and storage. This thesis will study architectures and techniques for creating a smart energy grid choosing suitable scenarios like (i) domestic or industrial customers (ii) electric vehicular scenarios.

Piero Castoldi, Isabella Cerutti

Realizzazione tramite Field Programmable Gate Arrays (FPGAs) di protocolli di controllo di reti ottiche passive atti al risparmio energetico. In the literature it has been shown that allowing Optical Network Units (ONUs) of Passive Optical Networks (PONs) to dinamically switch to stand-by when idle (i.e., sleep-mode), sensibly reduces the energy consumption of the network customer edge. The aim of this thesis is to implement a testbed to experimentally assess the aforementioned benefits. The tetsbed will involve the implementation, after the ONU Clock and Data Recovery Circuit, of the protocol to control the ONU and to control the ONU sleep mode in a Field Programmable Gate Array (FPGA). Requirements for this thesis are good programming skills, understanding of combinatorial networks, and network protocols.

Laura Ricci, Massimo Coppola

Consistency Models for Distributed Multiuser Virtual Environments

Massively Multiuser Environments (MME) are virtual worlds where multiple participants share the

same virtual environment and interact with it and among themselves via avatars, that are virtual

representation of users. Even if most commercial MME (World of Warcraft, Second Life,..) exploit a

client server architecture, the investigation of a distributed MME architecture integrating P2P and

clouds is currently an active research area. The replication of the virtual world over a set of nodes

requires the definition of a proper consistency model. Strong consistency models adopted in

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client/server MME are not suitable for distributed MME because of their implementation overhead.

This thesis will investigate existing optimistic consistency models proposed in the literature in order

to propose a proper consistency model for distributed MME. The benefits of the proposed solution

will be assessed through the development of a prototype.

Laura Ricci, Massimo Coppola

Locality Aware Service Mapping for Distributed Virtual Environments

Several P2P applications require the dynamic mapping of a set of services to peers so that several

constraints on hardware capabilities, security and stability of peers are satisfied. For instance in a

Distributed Virtual Environment (DVE) where the workload is paired with the egions of the virtual

world, a dynamic election of the 'best peer' for the management of a egion is required. This thesis

will investigate the problem of the definition of a locality-aware mapping of the DVE's regions to the

peers of an heterogeneous network. The main aim of the locality-aware mapping is the minimization

of the latencies between the peer providing the service and the set of peers accessing it. The

candidate will exploit Network Coordinates Systems (NCSs) as tool to predict network latencies in a

distributed fashion. The thesis will also evaluate different distributed paradigms (Voronoi Networks,

gossip P2P networks) to select an optimal mapping.

Massimo Coppola

QoS control and resource selection in Federated Clouds

QoS control over virtual resources is one of the features and active research issues of nowadays Cloud

Computing platforms. Federated Clouds, where resources from different Cloud providers can be

merged into a single pool, are an emerging evolution. The thesis will investigate algorithms for

matching application constraints and needs when allocating resources out of federated Clouds, taking

into account the computation, communication, trustworthy and security features provided by different

Cloud providers.

Massimo Coppola

Software Virtual Machines integration in Cloud platforms

Most of the emerging Cloud Computing platforms leverage processor-level virtual machines,

providing the parallel programmer with the abstraction of many freshly-installed isolated systems. The

thesis will survey existing approaches which provide richer functionalities and API to the programmer,

and then explore the integration of state-of-the-art process-level virtual machines (CLI - mono) with

the XtreemOS distributed operating system.

Massimo Coppola

Distributed JIT compilation for multicore cpus.

Starting from current experiments in building a CLI bytecode virtual machine which is able to

dynamically offload the task of JIT compilation to other linked virtual machines, the thesi(s) will

explore the different settings where the technique may lead to better efficiency, higher cache

utilization and/or smaller memory footprint of the overall system, with main focus on homogeneous

and heterogeneous multicore CPUs.

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Stefano Giordano, Vittorio Miori

Learning from experience to anticipate inhabitants’ needs in an invisible way

The embedded intelligence provides a vision of Internet of Things oriented to Ambient Intelligence

paradigm, which can be defined as the ability to collect and analyze the digital traces left by people

when they interact with the environment and with intelligent devices, to acquire knowledge about

life and human behavior.

The thesis work should apply these concepts within the domestic environment, where devices

(sensors and actuators) are already "things" with their own intelligence.

According to the principles of the semantic information processing (Web 3.0) will be implemented

an application based on machine learning systems (eg. Data Mining techniques). The result will be

an intelligent universal ecosystem who learns from the behavior and habits of the people and being

able to adapt itself to the environmental context and to anticipate user needs.

The developed system could be aimed at improving the comfort inside homes and it could try to

anticipate or to prevent potential health hazards (especially for elderly, disabled or sick).

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Theses proposed by Paolo Pagano, Matteo Petracca, and Marco Di Natale

All theses (apart from thesis proposal C.1) will be supervised by Dr. Paolo Pagano, Dr. Matteo Petracca, and

prof. Marco Di Natale.

Thesis proposal C.1 will be supervised by Dr. Paolo Pagano, Dr. Matteo Petracca, and prof. Ernesto

Ciaramella.

N.B. The hardware set to be used in the following proposals is described in the following on-line resources:

http://rtn.sssup.it/index.php/hardware/seed-eye

http://www.ipermob.org/files/documents/OO3/OO3-3-5v1.0.pdf

A) Computer vision in embedded systems

WSN are usually deployed through a set of embedded devices, equipped by

constrained resources (like computing capabilities and resident memory)

and interconnected by a low rate, unreliable wireless network.

Multimedia sensing is a challenging perspective to give “Eyes and Ears” to sensor devices and create added-

value to distributed applications in ad-hoc networks.

Thesis A.1)

One of the basic services provided by a Camera Sensor Network is that of notifying end-users or

other machines about the occurrence of (pre-defined) events. A simple application consists in

detecting the appearance of an entity in the foreground of an image frame having extracted the

background from a comparison with previous frames.

This thesis consists in the design and implementation of a background modeling algorithm for

embedded systems; the performance will be rated in a real testbed against state-of-the-art techniques

(from literature and previous work on the same subject) in respect of processing time, sensitivity,

probability of raising false alarms.

For reference:

L. Tessens, M. Morbee, W. Philips, R. Kleihorst, H. Aghajan, "Efficient approximate foreground

detection for low-resource devices", In Distributed Smart Cameras, 2009.ICDSC 2009. Third

ACM/IEEE International Conference on, pp. 1-8, 2009.

For the severe constraints in the computing resources every application based on multimedia streaming poses

a set of conceptual andimplementation problems related to information compression and algorithm

optimization.

Thesis A.2)

This thesis consists in the design and implementation of a compression algorithm for embedded

systems; a comparative analysis will be performed on a real IEEE802.15.4 WSN testbed for state-of-

the-art techniques like JPG, JPG-LS, JPG2000 considering the local processing time (at the sender

and the receiver node) and the network bandwidth utilization.

Thesis A.3)

The dogma of signal processing maintains that a signal must be sampled at a rate at least twice its

highest frequency in order to be represented without error. However, in practice, we often compress

the data soon after sensing, trading off signal representation complexity (bits) for some error

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(consider JPEG image compression in digital cameras, for example). Clearly, this is wasteful of

valuable sensing resources. Over the past few years, a new theory of "compressive sensing" has

begun to emerge, in which the signal is sampled (and simultaneously compressed) at a greatly

reduced rate (see on-line resources at: http://dsp.rice.edu/cs).

This thesis consists in the design and implementation of compressive sampling techniques for

optimizing the total energy dissipated in a distributed multimedia application for WSN.

For extending the local storage resources and the acquisition overhead in a sensing node, it is possible to

couple a microcontroller-based platform with an FPGA.

Thesis A.4)

This thesis consists in the design and implementation of a background modeling algorithm for

embedded systems by configuring an FPGA. A performance comparison (in terms of time overhead

and feasibility of advanced logic) with a “pure-C” implementation will be used to rate the validity of

this approach.

A very challenging application is that of tracking a moving object by means of a set of cameras hosting a

distributed collaborative application.

Thesis A.5)

This thesis consists in the design and implementation of a calibration technique aimed at aligning the

sensing peripherals after an imprecise installation phase.

For reference:

Stauffer C; Kinh Tieu; , "Automated multi-camera planar tracking correspondence modeling,"

Computer Vision and Pattern Recognition, 2003. Proceedings. 2003 IEEE Computer Society

Conference on , vol.1, no., pp. I-259- I-266 vol.1, 18-20 June 2003

doi: 10.1109/CVPR.2003.1211362.

B) Localization techniques

In the “Smart Ambients” domain a prominent application is that of locating and tracking moving objects.

For the unavailability of the GNSS signal in indoor scenarios, usual trends consider the deployment of a

WSN to set up a mesh of geo-referenced anchors and propose a diversified set of algorithms (usually

classified in “range-based” and “range-free”) as localization techniques.

Thesis B.1)

This thesis consists in the design and implementation of a sensor fusion service aimed at estimating a

statistical variable from its analytical dependence on simple sensor data. The experimental validation

activity will be coupled with a simulation study to isolate the error sources limiting the service

accuracy.

A competing and complementary approach is that of relying on inertial sensors to estimate the motion and

quantify the displacement of the mobile entity.

Thesis B.2)

This thesis consists in the modeling of the motion of a mobile entity by real-time processing of the

data retrieved by inertial sensors (like accelerometers and gyroscopes) integrated as electronic

components in embedded devices. The candidate will be asked to design and implement a

synchronization service to re-align the estimated position to the ground truth retrieved by a device of

different technology (e.g. RFID or GNSS signal transponder).

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C) Networking

Vehicular Ad-hoc NETworks (VANET) are a special instance of nomadic networks where the mobile

entities (i.e. cars) are expected to exchange information (vehicle to vehicle -- V2V) via the wireless channel.

VANET technologies are considered as the basis of Intelligent Transport Systems; yet another challenge is

that of interconnecting vehicular equipment with the road-side network (vehicle to infrastructure -- V2I).

Thesis C.1)

Although Radio Frequency is the preferred technology for enabling V2I and V2V communication

(see for instance the M/453 mandate by the European Commission to ETSI and CEN), alternative

communication means are being promoted by the scientific community. A notable example is

offered by Visible Light Communication.

At the lab, the implementation of the functionality of ITS stations (standardized by ETSI) in tiny

devices (like WSN) communicating in compliance with the IEEE802.15.4 standard, is in progress.

This thesis will extend the physical layer of the ITS stack to permit the encoding of application layer

messages using VLC. The experimental validation activity will be focusing on the metrics relevant

for safety-critical applications (i.e. overhead in sending and receiving).

Wireless Multimedia Sensor Networks (WMSNs) can be considered a next generation of sensor networks in

which multimedia capabilities, both video and audio, have been enabled on tiny mote devices. Main

challenge from a network point of view must be considered the QoS, to be reached through simple or

complex data protection techniques (cross-layer approaches).

Thesis C.2)

Speech communications in WMSNs have been recently proposed to support emergency situations. In

such a context the network is required to change at runtime its functionality in order to support the

new service. Moreover, a network reorganization is required to support QoS.

The thesis will define and implement a Bandwidth allocation protocol targeted to Speech

communications on WMSNs. The main goal of the protocol will be the research of a trade-off

between QoS and required transmission bandwidth by using a speech coder with multiple bitrates

(e.g., G726 - 16, 24, 32 , 40 kbit/s).

Thesis C.3)

We propose a thesis where the candidate is expected to port the GSM AMR speech coder to a

microcontroller architecture. A comprehensive perform evaluation will be done in a real WSSN

scenario considering multiple data protection techniques.

The Internet of Things (IoT) vision has recently drawn the attention of the research community thanks to the

wide diffusion of the Internet to new, miniaturized, and low-cost smart objects. The main idea in the IoT

concept is to interconnect different kinds of common objects, each one addressable for exchanging data

through a single world-wide network. In this regard a significant and promising trend is given by the

integration of the Wireless Sensor Networks (WSNs) with the Internet.

Thesis C.4)

WSNs consist of low-cost autonomous sensor devices which interact with each other in a wireless

distributed system. Each sensor has very limited battery capacity, limited processor capability and

limited storage capacity. Multicast paradigm reduces the communication costs for applications that

send the same data to multiple recipients: instead of sending via multiple unicasts, multicasting

minimizes the link bandwidth consumption, sender and router processing, and delivery delay.

The thesis will design and implement a Multicast protocol for Wireless Sensor Network. The main

goal is to define a native multicast support for 6LoWPAN network (IPv6 over Lossy and Low

Power Network). The experimental validation activity will be performed in a real scenario.

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D) Abstraction of Wireless Sensor Networks

As applications become more and more interconnected and interdependent, the number of objects, users and

devices tends to increase. This poses the problem of the scalability of the communication and object

management algorithms, and increases the complexity of administration. Ubiquitous Computing is a vision

of the near future, in which an increasing number of devices embedded in various physical objects will be

participating in a global information network.

To set up a common ground of abstraction, a middleware layer should hide the heterogeneity of the network

and the complexity of services and applications.

A prominent objective is that of implementing a code execution service at the node level by implementing a

virtual machine capable of executing scripts or bytecodes.

Thesis D.1)

This thesis consists in the design and implementation of a network service for the rapid prototyping

of functions and primitives.

Leveraging the previous work on the same subject (i.e. the PyMite implementation on the

microcontroller board), the candidate is asked to apply tools and techniques to a real-world case

study (e.g. distributed vision algorithms).

Thesis D.2)

When dealing with a heterogeneous set of resources (notably sensor devices at the collection layer,

storage, and computation units) the usual trend is that of setting up a virtual architecture capable of

providing “high-level” services by interoperating the active devices integrated therein.

This thesis will consider the implementation of a set of collection layer services in a “grid” middleware (e.g.

the gLite platform developed within the European EGEE project and largely used by CERN and other public

research institutions).