Bernhard Collini-Nocker

Internet over direct broadcast satellites

High-powered direct broadcast television satellites can be used to broadcast high volumes of data directly to home terminals. Using the telephone network or a similar low-speed network, an asymmetrical system can be implemented which offers interactive Internet services. Two such interactive data broadcast systems are described which have been implemented as demonstration platforms for interactive multimedia services; one is based on digital subcarrier techniques for analog television channels, the other on the MPEG-2 and DVB standards. The architecture of the hardware and software is presented, particularly the solutions available for carrying Internet datagrams over MPEG-2 transport systems. A multicast transport protocol with selectable reliability is described which is the basis of a generic distribution application. It exploits the potential benefits of direct broadcast satellites for delivering data to large groups of local caches.

Analytical and Experimental IP Encapsulation Efficiency Comparison of GSE, MPE, and ULE over DVB-S2

Transmitting variable-length network layer (IP) packets over satellite links with fixed frame lengths (or lengths depending on the ACM transmission mode) requires (IP) encapsulation. For DVB-S links with fixed-size 188-byte TS packets, MPE and ULE encapsulations are available. DVB-S2 provides a compatibility mode to pack TS packets into the longer base band frames (BBFrames). Thus MPE and ULE are also available for S2, as well as a native generic stream encapsulation (GSE), avoiding the double overhead of TS and BBFrame encapsulation. The present paper gives a short overview on the available encapsulation protocols for DVB-S2, and then provides a mathematical efficiency calculation model for these encapsulations, in order to allow for performing theoretical efficiency simulations. Comparison graphs of the efficiency values are presented, using both the efficiency models and measurements from real satellite traffic.

FIRST: Future Internet — a role for satellite technology

This paper identifies key research issues and technologies that we envision will be important to the continued evolution of satellite networking and its integration as a core component of a future Internet that offers reliable, robust and pervasive networking and access to network services.

GSE: A flexible, yet efficient, encapsulation for IP over DVB-S2 continuous generic streams

The second-generation specification for Digital Video Broadcast over Satellite, DVB-S2, defines an improved and adaptive physical layer. A new framing structure at the link layer, known as the generic stream (GS), is introduced offering an alternative to the well-known MPEG transport stream (TS). This paper presents the requirements for and the design of an encapsulation protocol to transport IPv4 and IPv6 datagrams and other network protocol packets directly over DVB-S2 using this GS profile. The resulting generic stream encapsulation (GSE) is a novel method that provides flexible encapsulation with support for fragmentation. A flexible extension header format allows GSE to carry additional header information, suitable for enhanced features, such as link layer encryption and IP header compression. The paper assesses GSE performance by simulation using realistic traffic profiles and attenuation fading. This demonstrates considerable improvement in efficiency compared with the MPE/MPEG-2 TS, especially when used with adaptive coding and modulation (ACM). Although designed for DVB-S2 systems, the new encapsulation is suitable for other second-generation physical layer standards. Copyright

Satellite Internet services using DVB/MPEG-2 and multicast Web caching

Communication satellites can be used to broadcast large volumes of data directly to extensive user groups. With the latest generation of high-powered direct broadcast satellites and the changing traffic and usage patterns in the Internet, new ways of using satellites for delivering data directly to the end user have become viable alternatives to terrestrial point-to-point networks. In this article the software architecture of a distributed system, which has been successfully implemented and which supports online and offline interactive multimedia services, is presented. It is based on a method of carrying Internet datagrams over DVB/MPEG-2 transport systems, intended for digital television. It relies on a configuration using a broadband forward channel and a separate, usually narrowband, return channel. The forward link is usually provided by a geostationary satellite, whereas the return channel uses a different network technology, such as dialup connection, a direct Ku-band return link, a LEO satellite network, or an LMDS local distribution system. A generic multicast system is presented which exploits the inherent capabilities of satellites to reach a large number of customers. The reliable multicast strategy chosen is shown to handle multiple applications, each with different reliability and timing requirements.

A lightweight encapsulation protocol for IP over MPEG-2 networks: design, implementation and analysis

Digital TV Broadcast standards (e.g., ATSC, DVB) offer a good solution to last mile Internet delivery. Satellites, terrestrial broadcast, and cable systems are well suited to the delivery of high bandwidth data to the end user. Low transport overhead and ready availability of MPEG-2 TS equipment make it very appealing as a bearer for connecting IP networks. The Multi-Protocol Encapsulation (MPE) is a standard for the transport of IP over DVB. However, MPE has a number of shortcomings and inefficiencies when supporting next generation Internetworking systems. This paper describes a new method for the encapsulation of IPv4/IPv6 datagrams, known as the Ultra Lightweight Encapsulation (ULE) that overcomes limitations of MPE. The paper provides the rationale for developing ULE and provides measurements and analysis to show that the new scheme can offer additional functionality while achieving increased transmission efficiency.

A scenario of voice services delivery over enterprise W/LAN networked platform

The converged communication applications unlock business value. The value grows with the convergence extension into new areas. These applications increase the speed and agility of the enterprises, managements ability to control operations. Moreover, they handle seamlessly voice, data, and multimedia across multiple wireline and wireless access technologies. Also, enterprises are now considering how to extend their networks by IP voice over WLANs. This process starts with an analysis of a network infrastructure, services and applications, including the potential for converged services, as well as the technology for the transition to future services. In this paper, we examine a network architecture that spans WLAN and LAN to facilitate a seamless delivery of voice services across an enterprise. We build service scenario framework for this architecture. And, we propose a mathematical model of the delivery framework in order to analyze network behavior as a response to the new services introducing.

Enterprise network maintaining mobility – architectural model of services delivery

Purpose – Global commerce demands flexibility in when and how work gets done, as modern businesses increasingly require real‐time responses to partners and customers. With low costs, companies look to mobility as a way to speed responsiveness and increase the personalization of customer service offerings. Mobility is a key element of networking allowing enterprises to unlock their business process from fixed points. A unified approach to enterprise mobility delivers integrated wired/wireless networking, mobile extensions to unified communications, geographic, and end‐point independent network access and location services as major architectural components. As a consequence, this paper aims to focus on a converged architecture that spans wired and wireless networks to enable a seamless delivery of integrated services across the enterprise.Design/methodology/approach – This paper builds a framework to facilitate a continuous delivery of voice services. It also examines an architecture that traverses wireless...

A Scenario of Service-Oriented Principles Adaptation to the Telecom Providers Service Delivery Platform

Telecom service providers face a challenge how to increase average revenue per user by new-generation services. In view of the fact that it is extremely difficult to predict the success of the certain kind of service(s), as a result the providers are in need for a dynamic architecture that has to be capable to deliver new services promptly, add resources for successful services as demand increases, or remove unsuccessful services effortlessly. Such architecture has to be a modular standards-based service platform that supports different protocols and interfaces as well as QoS-based transformations and gateways. The potential candidate for this delivery platform is Service Oriented Architecture (SOA). Thus, the aim of our work is to develop a SOA implementation methodology considering telecom service providers existing enterprise network architecture and potential future growth.

A second-generation architecture for Linux DVB networking

IP/DVB operating system support for the second generation DVB physical carriers is still limited to the so called broadcast profile that supports only CCM mode and encapsulation of IP packets into transport stream packets. Both MPE and ULE are currently used encapsulations therefore. The interactive profile, in contrast, provides a generic stream interface that allows for efficient use also in VCM and ACM mode and provides with GSE a new encapsulation. This paper presents a novel architecture for Linux kernel based operating systems to support second generation DVB carriers.