Search results for " telecomunicazioni"
showing 10 items of 245 documents
Cross-technology wireless experimentation: Improving 802.11 and 802.15.4e coexistence
2016
In this demo we demonstrate the functionalities of a novel experimentation framework, called WiSHFUL, that facilitates the prototyping and experimental validation of innovative solutions for heterogeneous wireless networks, including cross-technology coordination mechanisms. The framework supports a clean separation between the definition of the logic for optimizing the behaviors of wireless devices and the underlying device capabilities, by means of a unifying platform-independent control interface and programming model. The use of the framework is demonstrated through two representative use cases, where medium access is coordinated between IEEE-802.11 and IEEE-802.15.4 networks.
Demand Response Service Certification and Customer Baseline Evaluation Using Blockchain Technology
2020
The use of Distributed Ledger Technologies such as Blockchain for certifying Demand Response services allows for the creation of a distributed system in which customers can communicate with the system operator to provide their flexibility, in a secure, transparent and traceable way. Blockchain technology also supports incentive mechanisms for users taking part in the service through the generation of utility tokens to recognize the user's contribution. This paper presents the experimental test of a novel methodology for Demand Response programs implementation by using the Blockchain technology. The latter is employed for defining a distributed Demand Response service and a new system for it…
Pricing Schemes for Emerging Telecommunication Market
2012
Statistical analysis of RaptorQ failure probability applied to a data recovery software
2014
In this work, we have implemented a data recovery software integrating the most recent rateless codes, i.e., RaptorQ codes. Thanks to the above-mentioned software, it is possible to recover data loss occurring on several kinds of network conditions. We have performed a statistical analysis of failure probabilities at several configurations of RaptorQ parameters. We have found a good agreement with the theoretical values of a random linear fountain code over Galois Field GF(256). Moreover, we have shown that the probability of having a certain number of failed decoded source blocks - when sending a fixed size file - follows a Poisson distribution.
Indoor free space optics link under the weak turbulence regime: Measurements and model validation
2015
In this study, the authors present the measurements performed on a free space optics (FSO) communications link using an indoor atmospheric chamber. In particular, the authors have generated several different optical turbulence conditions, demonstrating how even the weak turbulence regime can strongly affect the FSO link performance. The authors have carried out an in-depth analysis of the data collected during the measurements, and calculated the turbulence strength (i.e. scintillation index and Rytov variance) and the important performance metrics (i.e. the Q-factor and bit error rate) to evaluate the FSO link quality. Moreover, the authors have tested, for the first time, an appositely de…
An explanation for unexpected 802.11 outdoor link-level measurement results
2008
This paper provides experimental evidence that "weird'/poor outdoor link-level performance measurements may be caused by driver/card-specific antenna diversity algorithms unexpectedly supported/activated at the WLAN transmitter side. We focus our analysis on the Atheros/MADWiFi card/driver case, and we observe that the transmit antenna diversity mechanisms remain by default enabled when the available antennas are not homogeneous in terms of gain or, even worse, when only a single antenna is connected. This may cause considerable performance impairments (large frame loss ratio), in conditions frequently encountered in outdoor link deployments. The negative impact of transmit antenna diversit…
WCMA:tecniche di accesso e codifica canale
2005
One size hardly fits all
2013
This paper casts recent accomplishments in the field of Wireless MAC programmability into the emerging Software Defined Networking perspective. We argue that an abstract (but formal) description of the MAC protocol logic in terms of extensible finite state machines appears a convenient and viable data-plane programming compromise for modeling and deploying realistic MAC protocol logics. Our approach is shown to comply with existing control frameworks, and entails the ability to dynamically change the MAC protocol operation based on context and scenario conditions; in essence, move from the traditional idea of "one-size-fits-all" MAC protocol stack to the innovative paradigm of opportunistic…
MAClets: Active MAC Protocols over hard-coded devices
2012
We introduce MAClets, software programs uploaded and executed on-demand over wireless cards, and devised to change the card's real-time medium access control operation. MAClets permit seamless reconfiguration of the MAC stack, so as to adapt it to mutated context and spectrum conditions and perform tailored performance optimizations hardly accountable by an once-for-all protocol stack design. Following traditional active networking principles, MAClets can be directly conveyed within data packets and executed on hard-coded devices acting as virtual MAC machines. Indeed, rather than executing a pre-defined protocol, we envision a new architecture for wireless cards based on a protocol interpr…
Design, Implementation and Experimental Evaluation of a Wireless MAC Processor over commercial WIFI cards
2014
In this thesis we face the problem of wireless network programmability as a solution for coping with context-dependent optimizations, moving from one-for-all standard solutions to the concept of programmable wireless interfaces. Although the wireless research and academic community has proposed interesting platforms (e.g. based on Software Defined Radio) for pushing forward dynamic reprogrammability of devices, we argue that it is important to identify a tradeoff between programmability space and usability of the programmable interface. In this direction, we introduce the concept of Wireless MAC Processor and developed a running prototype over an ultra-cheap wireless card. Wireless MAC proc…