Design issues for the Generic Stream Encapsulation (GSE) of IP datagrams over DVB-S2

The DVB-S2 standard has brought an unprecedented degree of novelty and flexibility in the way IP datagrams or other network level packets can be transmitted over DVB satellite links, with the introduction of an IP-friendly link layer - he continuous Generic Streams - and the adaptive combination of advanced error coding, modulation and spectrum management techniques. Recently approved by the DVB, the Generic Stream Encapsulation (GSE) used for carrying IP datagrams over DVBS2 implements solutions stemmed from a design rationale quite different from the one behind IP encapsulation schemes over its predecessor DVB-S. This paper highlights GSE's original design choices under the perspective of DVB-S2's innovative features and possibilities

IP and ATM integration: A New paradigm in multi-service internetworking

ATM is a widespread technology adopted by many to support advanced data communication, in particular efficient Internet services provision. The expected challenges of multimedia communication together with the increasing massive utilization of IP-based applications urgently require redesign of networking solutions in terms of both new functionalities and enhanced performance. However, the networking context is affected by so many changes, and to some extent chaotic growth, that any approach based on a structured and complex top-down architecture is unlikely to be applicable. Instead, an approach based on finding out the best match between realistic service requirements and the pragmatic, intelligent use of technical opportunities made available by the product market seems more appropriate. By following this approach, innovations and improvements can be introduced at different times, not necessarily complying with each other according to a coherent overall design. With the aim of pursuing feasible innovations in the different networking aspects, we look at both IP and ATM internetworking in order to investigating a few of the most crucial topics/ issues related to the IP and ATM integration perspective. This research would also address various means of internetworking the Internet Protocol (IP) and Asynchronous Transfer Mode (ATM) with an objective of identifying the best possible means of delivering Quality of Service (QoS) requirements for multi-service applications, exploiting the meritorious features that IP and ATM have to offer. Although IP and ATM often have been viewed as competitors, their complementary strengths and limitations from a natural alliance that combines the best aspects of both the technologies. For instance, one limitation of ATM networks has been the relatively large gap between the speed of the network paths and the control operations needed to configure those data paths to meet changing user needs. IP\u27s greatest strength, on the other hand, is the inherent flexibility and its capacity to adapt rapidly to changing conditions. These complementary strengths and limitations make it natural to combine IP with ATM to obtain the best that each has to offer. Over time many models and architectures have evolved for IP/ATM internetworking and they have impacted the fundamental thinking in internetworking IP and ATM. These technologies, architectures, models and implementations will be reviewed in greater detail in addressing possible issues in integrating these architectures s in a multi-service, enterprise network. The objective being to make recommendations as to the best means of interworking the two in exploiting the salient features of one another to provide a faster, reliable, scalable, robust, QoS aware network in the most economical manner. How IP will be carried over ATM when a commercial worldwide ATM network is deployed is not addressed and the details of such a network still remain in a state of flux to specify anything concrete. Our research findings culminated with a strong recommendation that the best model to adopt, in light of the impending integrated service requirements of future multi-service environments, is an ATM core with IP at the edges to realize the best of both technologies in delivering QoS guarantees in a seamless manner to any node in the enterprise

Support For IP mobility and diversity in a broadband wireless access network

Broadband wireless access (BWA) network working at millimetre bands possesses the advantages of quick deployment, more flexibility, wide service coverage and cost efficiency. The range of services to be provided via the system includes broadband digital television, Internet data, telephony and videoconference. Apart from broadcast digital television, all traffic is carried in Internetworking Protocol (IP) format. Unfortunately the services of such a system are susceptible to impairment by buildings, vegetation, terrain and attenuation caused by rain, snow and sleet, etc. Accordingly the service availability and system performance can drop dramatically. In the worst case, the system will experience heavy packet loss and the services might be completely unavailable. An extended multiprotocol label switching (MPLS) network architecture is proposed in this thesis, which allows fast mobile IP access and diversity routing for traffic under fade condition. This supports nomadic access, reduced packet loss and improved service availability in BWA network during system outage. Also developed herein is a Diversity and Shadow Flow Merging Mechanism, which, besides sending a packet on its normal path, also duplicates the packet and sends it on a separate, diverted labelled path. The shadow flow merging mechanism is responsible for merging the normal flow and shadow flow together and delivering the merged packet to its destination. It is anticipated that the packet can be successfully delivered to the destination even if one path fails completely during the system outage. The protocol is tested on a general BWA network that is configured with Digital Video Broadcast (DVB) downlink and Multi-Frequency Time Division Multiplex Access (MF-TDMA) uplink equipments. The protocol’s ability of reducing packet loss and improving service availability, during the period of link failure, is verified. It is concluded that the protocol is effective in improving the service availability of BWA network.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Multimedia applications and network management support in Video Dialtone ATM network

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.Includes bibliographical references (leaves 63-64).by Dang Van Tran.M.S

The Political Nature of TCP/IP

Despite the importance of the Internet in the modern world, many users and even policy makers don’t have a necessary historical or technical grasp of the technology behind it. In the spirit of addressing this issue, this thesis attempts to shed light on the historical, political, and technical context of TCP/IP. TCP/IP is the Internet Protocol Suite, a primary piece of Internet architecture with a well-documented history. After at technical overview, detailing the main function of TCP/IP, I examine aspects of the social and developmental record of this technology using STS theoretical approaches such as Hughesian systems theory, Social Construction of Technology (SCOT), and Langdon Winner’s brand of technological determinism. Key points in TCP/IP evolution, when viewed from an STS perspective, illuminate the varied reasons behind decisions and development of the technology. For example, as detailed in this paper, both technical and political motivations were behind the architectural politics built into TCP/IP in the 1970s, and similar motivations spurred the rejection of OSI protocols by Internet developers two decades later. Armed with resultant contextual understanding of previous TCP/IP developments, a few possible directions (both political and technical) in contemporary and future Internet development are then explored, such as the slow migration to IPv6 and the meaning of network neutrality

Cross-layer enhancement of error control techniques for adaptation layers of DVB satellites

This paper assesses the way error control is managed jointly by Forward Error Codes (FEC) and Cyclic Redundancy Checks (CRC) in the lower layers of today’s Digital Video Broadcasting (DVB) satellites. Mathematical and simulation results clearly show that the outer block codes of the coding schemes used in DVB-S and DVB-S2 (Reed-Solomon and Bose-Chaudhuri-Hocquenghem, respectively) can provide very accurate error-detection information to the receiver in addition to their basic correction task at virtually no cost, making an uncorrected error after decoding an extremely improbable event. For this reason, the workload of CRCs can be ensured safely by the FEC subsystem if a dedicated function allowing the physical layer to share its decoding information with the adaptation layer is set. This particular crosslayer mechanism would allow freeing up the bandwidth currently used by CRCs -which adds up to 10 % for more than 35 % of the total number of IP packets- and pave the way for an enhanced transport of IP over DVB-S2