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Satellite Communication (SatCom) networks are become more and more integrated with the terrestrial telecommunication infrastructure. In this paper, we shows the current status of the still ongoing European Space Agency (ESA) project”Data-driven Network Controller Orchestration for Real time Network Management-ANChOR”. In particular, we propose a Long Short-Term Memory (LSTM)based methodology to drive the dynamic selection of the optimal satellite gateway station, which will be performed by combining different kinds of information (i.e. traffic profile, network and weather conditions). Some preliminary results on the real world dataset shows the effectiveness of the proposed approach.

The goal of this work was to understand the direction of the emerging web technologies and to evaluate their expected impact on satellite networking. Different aspects have been analysed using both real satellite testbeds and emulation platforms in different test sites in Europe. This analysis included an evaluation of those HTTP/2.0 specifications, which were implemented and released as open-source code in the experimental release of the SPDY protocol. SPDY performance was evaluated over satellite testbeds in order to understand the expected interaction with performance-enhancing proxies (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 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.

The goal of this work was to understand the direction of the emerging web technologies and to evaluate their expected impact on satellite networking. Different aspects have been analysed using both real satellite testbeds and emulation platforms in different test sites in Europe. This analysis included an evaluation of the SPDY protocol 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.

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.

Delay tolerant networking (DTN) is an emerging technology introduced for deep-space communications to address both very large propagation delay or link disruptions. The DTN paradigm results promising in several satellitebased scenarios where either physical or service interruption might be experienced. This paper focuses on a set of selected satellite-based scenarios, where the DTN paradigm adoption greatly improves the unicast and multicast communications' performance with limited costs in terms of both software add-ons and architectural modifications.

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.

The rapid evolution of the Web imposes the need of enhanc- ing the HTTP over satellite channels. To this aim, SPDY is a protocol engineered to reduce download times of content rich pages, as well as for managing links characterized by large Round Trip Times (RTTs) and high packet losses. With such features, it could be an efficient solu- tion to cope with performance degradations of HTTP over satellite. In this perspective, this paper compares the behaviors of HTTP and SPDY over a DVB-RCS satellite link. To conduct a thorough set of tests over a realistic scenario, we used the Satellite Network Emulation Platform (SNEP). In addition, we evaluated how different Bandwidth on Demand (BoD) methods impact over the retrieval of a page. Results clearly indi- cate that SPDY could be an effective solution to deliver Web contents over satellites in a more efficient manner.

This paper is not a survey related to generic wireless sensor networks (WSNs), which have been largely treated by Akyildiz et al. in [1], and later in a number of survey papers addressing more focused issues; rather, it specifically addresses architectural aspects related to WSNs in some way connected with a satellite link, a topic that presents challenging interworking aspects. The main objective is to provide an overview of the potential role of a satellite segment in the future wireless sensor networks. In this perspective, requirements of the most meaningful WSN applications have been drawn and matched to characteristics of various satellite/space systems in order to identify suitable integrated configurations.