Uveal melanoma (UM) represents the most common primary intraocular tumor, and nowadays eye plaque brachytherapy (EPB) is the most frequently used visual acuity preservation treatment option for small to medium sized UMs. The excellent local tumor control (LTC) rate achieved by EPB may be associated with severe complications and adverse events. Several dosimetric and clinical risk factors for the development of EPB-related ocular morbidity can be identified. However, morbidity predictive models specifically developed for EPB are still scarce. PRISMA methodology was used for the present systematic review of articles indexed in PubMed in the last sixteen years on EPB treatment of UM which aims at determining the major factors affecting local tumor control and ocular morbidities. To our knowledge, for the first time in EPB field, local tumor control probability (TCP) and normal tissue complication probability (NTCP) modelling on pooled clinical outcomes were performed. The analyzed literature (103 studies including 21,263 UM patients) pointed out that Ru-106 EPB provided high local control outcomes while minimizing radiation induced complications. The use of treatment planning systems (TPS) was the most influencing factor for EPB outcomes such as metastasis occurrence, enucleation, and disease specific survival, irrespective of radioactive implant type. TCP and NTCP parameters were successfully extracted for 5-year LTC, cataract and optic neuropathy. In future studies, more consistent recordings of ocular morbidities along with accurate estimation of doses through routine use of TPS are needed to expand and improve the robustness of toxicity risk prediction in EPB.

Objectives: Tbx1 mutant mice are a widely used model of 22q11.2 deletion syndrome (22q11.2DS) because they manifest a broad spectrum of physical and behavioral abnormalities that is similar to that found in 22q11.2DS patients. In Tbx1 mutants, brain abnormalities include changes in cortical cytoarchitecture, hypothesized to be caused by the precocious differentiation of cortical progenitors. The objectives of this research are to identify drugs that have efficacy against the brain phenotype, and through a phenotypic rescue approach, gain insights into the pathogenetic mechanisms underlying Tbx1 haploinsufficiency. Experimental Approach: Disease model: Tbx1 heterozygous and homozygous embryos. We tested the ability of two FDA-approved drugs, the LSD1 inhibitor Tranylcypromine and Vitamin B12, to rescue the Tbx1 mutant cortical phenotype. Both drugs have proven efficacy against the cardiovascular phenotype, albeit at a much reduced level compared to the rescue achieved in the brain. Methods: In situ hybridization and immunostaining of histological brain sections using a subset of molecular markers that label specific cortical regions or cell types. Appropriate quantification and statistical analysis of gene and protein expression were applied to identify cortical abnormalities and to determine the level of phenotypic rescue achieved. Results: Cortical abnormalities observed in Tbx1 mutant embryos were fully rescued by both drugs. Intriguingly, rescue was obtained with both drugs in Tbx1 homozygous mutants, indicating that they function through mechanisms that do not depend upon Tbx1 function. This was particularly surprising for Vitamin B12, which was identified through its ability to increase Tbx1 gene expression. Conclusion: To our knowledge, this is only the second example of drugs to be identified that ameliorate phenotypes caused by the mutation of a single gene from the 22q11.2 homologous region of the mouse genome. This one drug-one gene approach might be important because there is evidence that the brain phenotype in 22q11.2DS patients is multigenic in origin, unlike the physical phenotypes, which are overwhelmingly attributable to Tbx1 haploinsufficiency. Therefore, effective treatments will likely involve the use of multiple drugs that are targeted to the function of specific genes within the deleted region.

Traceroute is a popular network diagnostic tool used for discovering the Internet path towards a target host. Besides network diagnostic, in the last years traceroute has been used by researchers to discover the topology of the Internet. Some network administrators, however, configure their networks to not reply to traceroute probes or to block them (e.g. by using firewalls), preventing traceroute from providing details about the internal structure of their networks. In this paper we present camouflage traceroute (camotrace), a traceroute-like tool aimed at discovering Internet paths even when standard traceroute is blocked. To this purpose, camotrace mimics the behavior of a popular TCP-based application-level protocol. We show preliminary results that confirm that camotrace is able to obtain additional information compared to standard traceroute.

The work described in this technical note is part of the technological development activities, for the year 2018, related to the H2020 project ACTIVAGE, a European Multi Centric Large Scale Pilot on Smart Living Environments.

Lutetium beta-tricalcium phosphate Ca9Lu(PO4)(7) was synthesized by solid-state reaction at 1200 degrees C, and investigated by means of a combination of scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies. SEM morphological analysis reveals the presence of sub spherical and prismatic micro crystalline aggregates, while EDS semi-quantitative analysis confirms the nominal Lu/Ca composition. The unit cell and the space group were determined by X-ray powder diffraction data showing that the compound crystallizes in the rhombohedral R3c whitlockite-type structure, with unit cell constants a = b = 1.04164(1) nm, c = 3.7302(1) nm and cell volume V = 3.5051(1) nm(3). The investigation was completed with the structural refinement by the Rietveld method, and discussion of the distribution of Lu within cationic sites according to the results of the Rietveld refinement. The FTIR and Raman spectra, correlated to isostructural rare earth phosphates from literature, show slight band shifts of the phosphate modes correlated to the evolving size of the rare earth elements. (C) 2018 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.

Rare earth elements doped (beta-tricalcium phosphates Ca9RE(PO4)(7) (RE = La, Pr, Nd, Eu, Gd, Dy, Tm, Yb) were synthesized by solid-state reaction at T = 1200 degrees C. The obtained RE-doped beta-TCP phases were studied by a combination of Scanning Electron Microscopy (SEM) equipped with energy dispersive X-Ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier Transform Infra Red (FTIR) and Raman spectroscopies. SEM morphological analyses revealed the presence of sub spherical micro crystalline aggregates, while EDS semi quantitative analyses confirmed the nominal RE/Ca composition for all the phases. The unit cell and the space group were determined by X-ray powder diffraction data showing that all phases in the series crystallize in the rhombohedral R3c whitlockite-type structure; the unit cell constants are a linear function of the dimension of the substituting rare-earth element, and range from a = b = 10.4695(3) angstrom, c = 37.500(3) angstrom and V= 3559.7(2) angstrom(3) (La) up to a = b = 10.4073(2) angstrom, c = 37.2725(2) angstrom, V = 3496.2(2) angstrom(3) (Yb). The analysis of each compound was completed with the structure model refinement by the Rietveld method and the distribution of RE within the available structural sites is discussed according to the results of the Rietveld refinement. The FTIR and Raman spectra show slight band shifts of the phosphate modes correlated to the evolving size of the RE element.

Nowadays, Machine-to-Machine(M2M) and Internet of Things (IoT) traffic rate is increasing at a fast pace. The use of satellites is expected to play a large role in delivering such a traffic. In this work, we investigate the use of two of the most common IoT/M2M protocols stacks on a satellite Random Access (RA) channel, based on DVB-RCS2 standard. The metric under consideration is the completion time, in order to identify the protocol stack that can provide the best performance level.

According to data traffic forecast reports, the volume of data transported by Internet in 2020 will exceed the threshold of 2.0 zettabytes per year, generated by more than trillion of devices. Only a minor portion of the traffic will be generated by PCs, as commonly observed in the recent past. On the contrary, a large quota of Internet traffic is expected to be generated by TVs, tablets, smartphones, and M2M devices. In particular, it has been highlighted that M2M traffic will experience a growth rate in the order of 60%. M2M refers to technologies that allow both wireless and wired systems to communicate with other devices of the same ability, sensors and actuators, without any human intervention. M2M applications are largely diffused in several deployments and have pushed the scientific community to thoroughly investigate the network design implications. The large amount of traffic contributed by these applications will have an important impact on the design of future network architecture and on dimensioning the capacity of the telecommunication infrastructures. From this standpoint, a special note has to be reserved to the case of M2M services distributed via satellite, whose related industry is continuously increasing in size, which is the main focus of this work. More generally, the research problem can be stated as follows: a large and dense population of M2M devices exchanges short data bursts over a shared satellite medium; support for sporadic and unpredictable access activity and/or support to delay-critical applications is required. Random Access (RA) schemes for handling uncoordinated multiple access can nowadays compete with the throughput offered by typical coordinated techniques, making the former ones strongly attractive to support large populations of M2M terminals, while contemporary providing immediate access to the channel, without any reservation delays that are typical of coordinated access schemes. Therefore, the focus of this Ph.D. Thesis is on analysing, analytically and empirically, the behaviour of the most common M2M protocol stacks on RA satellite links and on suggesting guidelines to improve the achievable performance level. The first part of this Thesis presents a load control algorithm to maximize the throughput achievable by RCSTs, focusing on the exploitation of linear code prior to transmission, in order to improve the transmission robustness at the cost of some capacity waste because of the redundancy. Furthermore, an innovative hybrid access protocol is designed, aiming at allowing the coexistence of M2M and non-M2M RCSTs in the same network. The second part of this Thesis studies the performance of M2M protocol stacks via RA satellite channels, when a reliable data delivery is needed in channels suffering of erasures due to collisions. Two metrics are taken into account: the completion time, in presence of short data bursts, and the throughput, in presence of a sustained load. A cross-layer study is proposed, in order to characterize the interactions among application, transport and M2M layers of a M2M protocol stack sending data via a RA satellite channel.

L'obiettivo di questo tirocinio è l'implementazione di un modulo di comunicazione multipath per il caso d'uso di trasmissione di flussi multimediali in real-time. Si definisce multipath una connessione in grado di sfruttare contemporaneamente piu` canali fisici di comunicazione fra sorgente e destinazione. Il modulo ha l'obiettivo principale di gestire la distribuzione del traffico sui diversi canali tramite un opportuno algoritmo di scheduling. Nella fase iniziale, il lavoro si è concentrato sulla ricerca dei protocolli multipath esistenti, nonchè delle piattaforme software in grado di soddisfare tale requisito. Sono stati dapprima individuati tre protocolli in grado di gestire comunicazioni multipath: . SCTP (Stream Control Transmission Protocol), descritto nel capitolo 1; . MP-TCP (Multipath-TCP), descritto nel capitolo 2; . MP-RTP (Multipath-RTP), descritto nel capitolo 3. Tale studio ha portato, infine, alla scelta del protocollo piu` adatto al caso d'uso proposto, ovvero MPRTP. Nella seconda fase, è stata selezionata la piattaforma software di riferimento, ovvero Gstreamer1, descritta nel capitolo 4.1, per la quale è presente un plugin che implementa il protocollo MPRTP. Su tale plugin - ancora in via di sviluppo - è stato implementato un algoritmo di scheduling che gestisca la distribuzione del traffico multimediale sui flussi multipath, in accordo con le statistiche di ciascun canale.

Internet e? una rete mondiale di reti di computer ad accesso pubblico, at- tualmente rappresentante il principale mezzo di comunicazione di massa, che offre all'utente una vasta serie di servizi e contenuti potenzialmente in- formativi. Cio? e? reso possibile utilizzando una suite di protocolli di rete comune chiamata TCP/IP. Tutti i dispositivi di centinaia di migliaia di reti, che formano Internet, usano questi protocolli per instradare i dati, ren- dere affidabile lo scambio di messaggi e comunicare tra di loro ad un livello superiore indipendentemente dalla loro sottostante architettura hardware e software, garantendo cosi? l'interoperabilita? tra sistemi e sottoreti fisiche diverse. Tuttavia vi sono ambienti e condizioni particolari in cui questi proto- colli non sono sufficienti ad assicurare un efficiente scambio di dati, come ad esempio le comunicazioni con dispositivi nello spazio (sonde, satelliti) che devono far fronte a condizioni estreme quali le distanze elevatissime, i ritardi di trasmissione, l'oscuramento e la perdita del segnale dovuto a inter- posizione di corpi celesti e elevati disturbi dovuti ai campi elettromagnetici planetari. Per questo motivo nasce la DTN (Delay - Distruption Tolerant Network), una rete di telecomunicazioni, attualmente in fase di sviluppo, che si propone come obiettivo la possibilita? di fare comunicare tra loro re- ti indipendenti, mutuamente incompatibili e non appartenenti a Internet, anche in assenza di un percorso continuo end-to-end. In parallelo viene sviluppato il bundle protocol, un nuovo protocollo posto ad un livello intermedio fra l'applicazione e il trasporto nello stack ISO/O- SI. Il campo di applicazione e? quindi quello dell'esplorazione dello spazio e proprio per questo motivo tali studi sono supportati attivamente dalla NASA.

This paper surveys the most popular random access (RA), demand assignment (DA), and hybrids schemes for satellite broadband access networks. In addition, we present some recent research results we obtained when a reliable transmission control protocol, i.e. TCP, is coupled with the most promising RA methods foreseen in the second generation of DVB-RCS standard. In fact, the necessity to support a wider range of IP-based traffic, as in the case either of Supervisory Control And Data Acquisition (SCADA) systems or Machine-to-Machine (M2M) communications, fosters the introduction of random access schemes for information transport able to cope with large network sizes and low duty cycle bursty traffic with frequent inactivity periods on the return link. As an indication of future research aspects we also offer, in the conclusions section, a list of items to be investigated so that satellite can become integral part of the Future Internet.

The deployment of sensor networks for emergency management must be considered as an irreplaceable support for both monitoring and rescue activities. Depending on the scenario the use of satellite links as a segment of the network ensures connectivity where no other network is available and in some case can also provide an efficient and cost effective means to transfer data. This work aims to define architecture, to identify of optimum solution and to evaluate performance, in terms of throughput and service delay, when a protocol stack - from layer II to layer IV - is considered over a DVB-RCS system. The considered platform is composed of clusters of sensors (including low data rate devices and bulk data cameras) deployed over vast geographical areas, which collect on ground and distribute via satellite multimedia information, i.e. audio, video and sensed data, either for emergency or monitoring operations. A geostationary system was selected in order to guarantee high flexibility in terms of channel capacity. The proposed architecture assumes a session layer protocol, between the transport and application layers, which manages the multiplexing of streams coming from the input sources. The proposed architecture integrates wireless sensor networks and satellite networks, implying to approach technological issues from access layer up to transport and session layers, with heterogeneous traffic sources multiplexed by a satellite gateway, before being encapsulated into TCP/IP flows. Simulation results show the validity of the proposed architecture and protocol solutions.

The new paradigm of web usage has motivated in recent years a series of proposals to update the standard Internet protocols related to web traffic. Some of these proposals provided suggestions to upgrade or even completely replace current Hypertext Transport Protocol (HTTP). Others, instead, focused on new TCP transport mechanisms (larger initial window, fast connection open, congestion window validation, tail loss probe, etc.) that are meant to accelerate the completion time of short data transfers. Web technologies are penetrating areas of computer-science before only the prerogative of dedicated computer systems, such as Cloud computing and Service- oriented applications. Web technologies are becoming increasingly prevalent as the delivery model for a wide range of applications, using methods such as Service- oriented architecture (SOA) or software as a service (SaaS). These methods implement the concept of ASP (application service provider) and on-demand computing software delivery: the provider hosts commercially available software and delivers copies of it over the Web, customising the software according to a client's needs. These changes are driving significant alterations in the traffic patterns generated by applications, but the impact of such changes are still uncertain. These changes are also set to change the requirements placed on a network - with an increasing emphasis on minimising web page download time, and an increasing need to consider on-off interactivity. The motivation for transport changes is a growing availability of high speed xDSL/cable access. These high-speed services differ from most wireless and satellite systems in key ways. Current wireless/satellite systems typically employ dynamic capacity schemes with protocol accelerators and access methods that have been tuned for the existing web traffic. The traffic patterns and protocol behaviour of new web protocols is very different. It is therefore important to assess the implications on the design and operation of satellite systems as the new web is increasingly used. This is the focus of this document. The document (TN3.1) reviews the current state-of-the-art of web technologies and surveys the recent proposals, such as SDPY. This document reviews the problems these protocols are trying to solve, and notes the way they try to solve them. In particular, the HTTP/2.0 standard is a new Internet application-layer that defines a new semantic. This is presently a joint effort between the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF). The starting point for the standard inherits ideas from SPDY, an open standard developed by Google and currently available in a wide range of web browsers, including Chromium, Mozilla Firefox and Opera. HTTP/2.0 promises to reduce web page load latency and improve web security using a combination of techniques, including compression, and multiplexing.

This project explores the potential implications of introducing the HTTP/2.0 web technology on the design and operation of satellite networks. It has been recognised that as network bandwidth increases, the greater obstacle to the performance of web technology is latency rather than scarcity of capacity. HTTP/2.0 [RD-8] is a new protocol being design by the Internet Engineering Task Force (IETF) and World Wide Web Consortium (W3C) to address the limitations and lack of flexibility of the currently widely deployed HTTP/1.1 [RD-4]. The origin of the emerging HTTP/2.0 standard may be traced back to a GoogleTM suite of protocols, called SPDY. Proposed modifications to HTTP/1.1 include suppression of unnecessary Round Trip Time (RTT) delays to request and deliver web objects, multiplexing of web streams into a single connection, removal of the head of line (HoL) blocking, more compact encoding of HTTP headers, server initiated transmissions (Server Push), a new security model, and an extensible design. In parallel, a number of initiatives from well-known IT actors (GoogleTM, AppleTM etc) have proposed new transport methods, such as QUIC [RD-7] or Minion [RD-23], to enhance performance for web traffic. It is expected that the final HTTP/2.0 specification will replace HTTP/1.1 in every scenario HTTP/1.1 is currently used. The goal of Task3 of CoO3 Satnex-III was to understand the trajectory of the emerging web technologies and to evaluate the expected impact on satellite networking. Different aspects have been analysed by Satnex partners using both real satellite testbeds and emulation. This analysis included evaluation of SPDY performance over satellite and experiments to understand the expected interaction with PEPs (including scenarios with a SPDY proxy at a satellite gateway), the impact of security, and the effect of satellite capacity allocation mechanisms. The analysis also considered the impact of application protocols and the delay induced by end- system networks, such as a satellite-connected WiFi network. In general, experimental results show that HTTP/2.0 benefits the performance of web browsing via satellite by reducing latency and significantly lowering the overhead for several types of web pages. In particular, multiplexing a sequence of small web objects on a webpage onto a single connection enables siginicant gain and effectively reduces the HTTP overhead per object and per connection. The Server Push feature of HTTP/2.0, adds the ability for the server to send objects without explicit request, and was found particularly useful to reduce the download time. However these gains come at a cost, since they impact the design and operation of satellite networks. We also observed places where the tested implementations did not perform optimally, and were performance over satellite-connected WiFi networks was less than would be expected with HTTP/1.1. However, at the time of writing, the work on HTTP/2.0 is not complete and many mechanisms remain to be finalised. Modifications and adjustments are expected in future. Moreover, the current software support for HTTP/2.0 is not yet completely stable, and is expected to continue to evolve long after initial deployment. Satellite networking equipment will need to be updated to support HTTP/2.0. In particular, designs must re-consider the integration of PEPs withHTTP/2.0 and the updated security model, based on Transport Layer Security (TLS). TLS encryption prevents visibility of HTTP headers at satellite equipment, preventing use of current 23089/10/NL/CLP Executive and Summary Report 15/40 III CoO3 - Task 3 - Future Web Technologies and Protocols over Broadband GEO Satellite Networks HTTP acceleration PEPs. Our tests suggest that this problem may be mitigated by HTTP/2.0 itself, because some of the functions implemented in application-layer PEPs (compression, pipeling/multiplexing, push) are already present in HTTP/2.0. HTTP/2.0 is still in a development phase and it is important for the satellite community to watch carefully its progress and understand the implications this will place on the design of the higher layer packet processing. This is especially important because the new model does not introduce a single solution, but more represents a toolkit of techniques that will continue to evolve and will be deployed incrementally over a timescale of months and years ahead. There is also a need to understand the implications on network design/configuration, to ensure that satellite continues to offer high quality service comparable to terrestrial networks, and a need to re-consider the role of PEP in this new architecture. We also urge the satellite networking community to influence development of these standards. As network latency becomes important there is increased focus on low- delay networks, and it is important to ensure that design decisions (maybe unintentional) do not prejudice the performance over long delay paths when the new protocols are deployed.

Random Access (RA) techniques have been included in the novel DVB-RCS2 standard due to an expected efficiency in addressing SCADA and M2M traffic. Such traffic relies on intermittent sources sending short messages on a periodic time scale. Efficiency is usually assessed in terms of layer-2 packet loss rate without taking into account indirect effects on upper layer protocols. In particular, TCP assumes packet losses as a congestion indication triggering actions aimed to reduce actual transmission rate. As a consequence, TCP over RA can be impaired by some cross-effects, which deteriorate the performance as experienced by the applications, in terms of Round Trip Time (RTT) and overall throughput. The scope of this paper is to analyze such dynamics, by applying a top-down approach, which includes TCP parameters tuning in the scenario configuration. To this aim, an NS2 module has been developed to simulate different flavors of random access techniques for GEO satellite channels integrated with sensor data sources, which produce intermittent messages and send them over TCP connections. Achieved results provide a first set of considerations on the best protocol stack configuration according to TCP traffic load.

This paper presents a performance study relative to the coupling of the Transmission Control Protocol (TCP) with the Contention Resolution Diversity slotted aloha (CRDSA) protocol, in the case of greedy TCP connections (also called elephants) on Digital Video Broadcasting-Return Channel via a geostationary satellite. CRDSA, which takes advantage of interference cancellation algorithms for collision/contention resolution, has already exhibited interesting performance when the power levels of all received bursts are perfectly balanced. In this paper, we extend the study to a more realistic case, where a certain spreading of the bursts' power levels is taken into account. The consequent capture effect even facilitates the collision resolution mechanism and yields an improvement in the overall TCP performance with respect to the balanced case. Furthermore, in certain conditions, the adoption of packet level forward error correction allows achieving even higher peaks of throughput than the expected ones. Copyright © 2014 John Wiley & Sons, Ltd.

In this paper, we propose a realistic architecture for the integration between wireless sensor and satellite networks, covering technological issues from the access layer up to the transport and session layers, when uncorrelated sensor sources generate measurements' data. These data are multiplexed by a satellite gateway before being encapsulated and delivered through TCP/IP flows. This work aims at investigating the convenience, in terms of access delay and employed resources, in using the new random access methods based on successive interference cancellation, while guaranteeing the same throughput performance of the demand assignment multiple access systems. Moreover, this is the first work that provides a queue analysis of a satellite random access technique compared with dedicated access techniques with both short- and long-lived elastic connections.

Owing to the variety of traffic profiles that Machine to Machine (M2M) and Internet of Things (IoT) applications may generate, this work studies the applicability of a DVB-RCS2 gateway when clusters of sensor nodes exchange data via satellite toward a central operational control station via TCP/IP connections. We propose a realistic architecture for the integration between wireless sensor and satellite networks, by covering technological issues from access layer up to transport and session layers. In this scenario, uncorrelated sensor sources generate measurements, which are multiplexed by a satellite gateway, before being encapsulated and delivered through TCP/IP flows. According to the traffic nature and the access methods in the DVB terminal, the suitability of a random access method in place of a dedicated one is an open issue, when throughput and delivery delay are the performance metrics at the transport layer. This work aims at investigating when the new random access methods, based on successive interference cancellation, are convenient with respect to dedicated access methods. The comparison is made in terms of access delay and employed resources, while the throughput is guaranteed comparable to the one obtained by using demand assignment multiple access systems. We outline that this is the first work that provides a queueing analysis for the comparison between random and dedicated satellite access techniques, when used by both short and long-lived TCP connections.

The new paradigm of web usage has motivated in recent years a series of proposals to update the standard Internet protocols related to web traffic. Some of these proposals provided suggestions to upgrade or even completely replace current Hypertext Transport Protocol (HTTP). Others, instead, focused on new TCP transport mechanisms (larger initial window, fast connection open, congestion window validation, tail loss probe, etc.) that are meant to accelerate the completion time of short data transfers. Web technologies are penetrating areas of computer-science before only the prerogative of dedicated computer systems, such as Cloud computing and Service-oriented applications. Web technologies are becoming increasingly prevalent as the delivery model for a wide range of applications, using methods such as Service-oriented architecture (SOA) or software as a service (SaaS). These methods implement the concept of ASP (application service provider) and on-demand computing software delivery: the provider hosts commercially available software and delivers copies of it over the Web, customising the software according to a client's needs. These changes are driving significant alterations in the traffic patterns generated by applications, but the impact of such changes are still uncertain. These changes are also set to change the requirements placed on a network - with an increasing emphasis on minimising web page download time, and an increasing need to consider on-off interactivity. The motivation for transport changes is a growing availability of high speed xDSL/cable access. These high-speed services differ from most wireless and satellite systems in key ways. Current wireless/satellite systems typically employ dynamic capacity schemes with protocol accelerators and access methods that have been tuned for the existing web traffic. The traffic patterns and protocol behaviour of new web protocols is very different. It is therefore important to assess the implications on the design and operation of satellite systems as the new web is increasingly used. This is the focus of this document. The document (TN3.1) reviews the current state-of-the-art of web technologies and surveys the recent proposals, such as SDPY. This document reviews the problems these protocols are trying to solve, and notes the way they try to solve them. In particular, the HTTP/2.0 standard is a new Internet application-layer that defines a new semantic. This is presently a joint effort between the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF). The starting point for the standard inherits ideas from SPDY, an open standard developed by Google and currently available in a wide range of web browsers, including Chromium, Mozilla Firefox and Opera. HTTP/2.0 promises to reduce web page load latency and improve web security using a combination of techniques, including compression, and multiplexing.

This paper presents a performance study relative to the coupling of the Transmission Control Protocol (TCP) with the franco.davoli@unige.it Contention Resolution Diversity Slotted Aloha (CRDSA) protocol, in the case of greedy TCP connections (also called elephants) on Digital Video Broadcasting-Return Channel via Satellite. CRDSA, which takes advantage of interference cancellation algorithms for collision/contention resolution, has already exhibited an interesting performance when the power levels of all received bursts are perfectly balanced. In this paper, we extend the study to a more realistic case that sees a certain spreading of the bursts' power levels. The consequent capture effect even facilitates the collision resolution mechanism and the overall TCP performance results improved with respect to the balanced case. Furthermore, in certain conditions, the adoption of packet level Forward Error Correction (FEC) allows handling system loads higher than the expected ones.