S Iyengar

Dynamics of key management in secure satellite multicast

Security is an important concern in todays information age and particularly so in satellite systems, where eavesdropping can be easily performed. This paper addresses efficient key management for encrypted multicast traffic transmitted via satellite. We consider the topic of encrypting traffic in large multicast groups, where the group size and dynamics have a significant impact on the network load. We consider life cycle key management costs of a multicast connection, and show for a logical key hierarchy (LKH) how member preregistration and periodic admission reduces the initialization cost, and how the optimum outdegree of a hierarchical tree varies with the expected member volatility and rekey factor. This improves network utilization, but encryption at the network layer can pose problems on satellite links. We, therefore, propose and analyze an interworking solution between multilayer Internet protocol security (IPSEC) and LKH that also reduces key management traffic while enabling interworking with performance enhancing modules used on satellite links.

Networking issues in IP multicast over satellite

This paper describes the issues that arise when using satellites for IP multicast, with the emphasis on multicast protocols and how their implementation depends on the satellite communications platform. Various link layer standards such as DVB-S, DVB-RCS and ATM can be used in satellites with onboard processing, and applied to meet user and network requirements for IP multicast. The paper provides an overview of the networking issues and their interactions. Specifically, we show how multicast networking protocols have to be modified to take into account the satellite link characteristics: these protocols include IGMP, multicast routing protocols and reliable multicast protocols. We also discuss how security systems support IP multicast.

Securing multicast in DVB-RCS satellite systems

While TV broadcasting is probably the best known application of satellite technology, satellite service providers are now expanding their services to include Internet data transmission. Consequently, security of satellite data is becoming an important issue. This article examines the current DVB-RCS security standard and identifies the principal gaps in the provision of secure multicast over DVB-RCS. The main contribution of this article is a proposal for adapting the current DVB-RCS two-way satellite standard to provide secure multicast services over satellites.

Security requirements for IP over satellite DVB networks

The MPEG-2 standard supports a range of transmission methods for a range of services. This document provides a threat analysis and derives the security requirements when using the Transport Stream, TS, to support an Internet network-layer using unidirectional lightweight encapsulation (ULE). The document also provides the motivation for link-level security for a ULE Stream. A ULE Stream may be used to send IPv4 packets, IPv6 packets, and other Protocol Data Units to an arbitrarily large number of receivers supporting unicast and/or multicast transmissions.

Security for FLUTE over Satellite Networks

Data transmission, such as software update, large file broadcasting and video on demand, can take advantage of the wide coverage and the broadcasting features of the satellite networks. The multicast technologies provide the support for these applications by efficiently using the expensive satellite bandwidth. One of them is the File Delivery over Unidirectional Transport (FLUTE) protocol [1] that is ideally for bulk of data reliable transmission over the satellite. However, FLUTE does not address any congestion control and security mechanisms. This paper is analyzing the advantages and drawbacks for security over different layers in a satellite network and presenting security considerations for the FLUTE over satellite networks by analyzing the threats and trying to provide security approaches at the Reliable Multicast Transport (RMT) layer for it. The work presented in this paper also analyzes the logical key hierarchy (LHK) for FLUTE protocol and gives the recommendation on the hierarchy structure for efficient re-key.

IP multicast over satellite

Satellites have been very successful for digital broadcast, and it is a natural step to develop IP multicast over satellite to explore the potential of the satellite systems. This paper discusses the issues of IP multicast over satellite, based on IP multicast protocols using different satellite communications systems including DVB-S and DVB-RCS. The paper provides an overview of the networking issues and their interactions. The work is based on the studies of the European IST GEOCAST project within the IST’s 5th Framework programme. The paper explains how IP multicast protocols can be implemented over satellite links, looking particularly at the issues involved in implementing IGMP, multicast routing protocols reliable multicast protocols, and security.

Fusion of digital television, broadband Internet and mobile communications - Part I: Enabling technologies

The introduction of digital video broadcasting (DVB) satellite systems has become an important tool for future mobile communication and is currently a focus in several research areas such as the integration of DVB satellite systems with different wireless technologies. This tutorial consists of two parts, Enabling technologies and Future service scenarios, which aims to provide an introduction to the current state-of-the-art of DVB standards over satellite and its fusion with mobile and Internet technologies. This paper, Enabling technologies, focuses on providing an overview of the different technologies and issues that facilitates better understanding of the current and future operational scenarios, whereas the second paper, Future service scenarios will emphasize future research directions in this research area. In the first part, the paper will initially be focused on the introduction of different DVB satellite systems, i.e. DVB-via satellite (DVB-S), DVB return channel by satellite (DVB-RCS) and second-generation DVB system for broadband satellite services (DVB-S2). This is then followed by a description of the different Internet Protocol (IP) technologies used to support macro- and micro-mobility and the migration strategies from IP version 4 (IPv4) to IP version 6 (IPv6). Finally, the different security mechanisms for the DVB system and end-to-end satellite network are addressed. Copyright

The SATSIX architecture for next-generation satellite systems with IPv6 and DVB

Broadband satellite will play an important role to provide universal broadband access for the users. In order to lower the cost, the next-generation satellite systems should support IPv6 and seamlessly integrate with terrestrial networks, including wireless local loops. In this paper, a novel network architecture has been proposed as a potential solution to the above problem. Based on the proposed overall network and functional architecture, we have emphasised and presented different aspects of the advanced IPv6-enable networking techniques, such as QoS, multicast, security and mobility. The transport protocols can be used in this network architecture are also studied.

IP Multicast over Satellites - Technology Challenges

This paper presents the research work carried out in the GEOCAST project, funded within the European 5 th Framework IST programme. It describes the challenges when using satellites for IP multicast, concerning networking technologies, satellite communications payload, IP multicast protocols, the role of satellites in the network and, in particular, the paper focuses on security. There are various security standards such as DVB-S, DVB-RCS, ATM and IPSec that can be applied to satisfy some of the user and network requirements. The paper provides an overview of these issues and the possible interaction between them. Then it examines in detail the topic of securing very large multicast groups, where the group size and group dynamics have great impact on networks and network security. It also presents key management distribution systems and a satellite key distribution architecture.

Secure Multicast in the Broadband Satellite Multimedia Networks

Satellites are expected to play an essential role in providing broadband and multicast services to regions that cannot be economically reached by terrestrial networks, in particular the more remote regions of Europe and the rest of the world. Security can be a problem for such global services. Security of multicast data is becoming an important issue to operators and users of satellite networks. This paper presents a proposed secure multicast architecture that fits well into the ETSI BSM overall architectural concepts. Multicast service scenarios with detailed security architecture are presented using the BSM standard interface between satellite dependent and independent layers. This architecture accommo- dates link and network layer security (Internet) security systems and interworking with non- satellite entities such as AAA, PEPs and COPs entities.