16,417 research outputs found

    Transport Protocol Throughput Fairness

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    Interest continues to grow in alternative transport protocols to the Transmission Control Protocol (TCP). These alternatives include protocols designed to give greater efficiency in high-speed, high-delay environments (so-called high-speed TCP variants), and protocols that provide congestion control without reliability. For the former category, along with the deployed base of ‘vanilla’ TCP – TCP NewReno – the TCP variants BIC and CUBIC are widely used within Linux: for the latter category, the Datagram Congestion Control Protocol (DCCP) is currently on the IETF Standards Track. It is clear that future traffic patterns will consist of a mix of flows from these protocols (and others). So, it is important for users and network operators to be aware of the impact that these protocols may have on users. We show the measurement of fairness in throughput performance of DCCP Congestion Control ID 2 (CCID2) relative to TCP NewReno, and variants Binary Increase Congestion control (BIC), CUBIC and Compound, all in “out-of-the box” configurations. We use a testbed and endto- end measurements to assess overall throughput, and also to assess fairness – how well these protocols might respond to each other when operating over the same end-to-end network path. We find that, in our testbed, DCCP CCID2 shows good fairness with NewReno, while BIC, CUBIC and Compound show unfairness above round-trip times of 25ms

    Towards a versatile transport protocol

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    n the context of a reconfigurable transport protocol, this paper introduces two protocol instances based on the com- position and specialisation of the TFRC congestion control and Selective Acknowledgment mechanisms. The two result- ing transport architectures lead respectively to the QTP_AF protocol, specifically designed to operate over QoS-enabled networks and the QTP_light protocol, specifically designed for resource-limited end systems connected to powerful servers. QTP_AF combines QoS-aware TFRC congestion control with full reliability to provide a transport service similar to TCP but additionally taking into account network-level band-width reservations. QTP_light proposes a modification of TFRC that shifts from the receiver to the sender the complexity of the loss rate estimation mechanism. This modification allows to alleviate the processing and communication load of "light" resource limited mobile receivers. We present the concept of these protocols and their adaptation in the EuQoS European project framework

    A Covert Data Transport Protocol

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    Both enterprise and national firewalls filter network connections. For data forensics and botnet removal applications, it is important to establish the information source. In this paper, we describe a data transport layer which allows a client to transfer encrypted data that provides no discernible information regarding the data source. We use a domain generation algorithm (DGA) to encode AES encrypted data into domain names that current tools are unable to reliably differentiate from valid domain names. The domain names are registered using (free) dynamic DNS services. The data transmission format is not vulnerable to Deep Packet Inspection (DPI).Comment: 8 pages, 10 figures, conferenc

    An Energy-conscious Transport Protocol for Multi-hop Wireless Networks

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    We present a transport protocol whose goal is to reduce power consumption without compromising delivery requirements of applications. To meet its goal of energy efficiency, our transport protocol (1) contains mechanisms to balance end-to-end vs. local retransmissions; (2) minimizes acknowledgment traffic using receiver regulated rate-based flow control combined with selected acknowledgements and in-network caching of packets; and (3) aggressively seeks to avoid any congestion-based packet loss. Within a recently developed ultra low-power multi-hop wireless network system, extensive simulations and experimental results demonstrate that our transport protocol meets its goal of preserving the energy efficiency of the underlying network.Defense Advanced Research Projects Agency (NBCHC050053

    Efficient Transport Protocol for Networked Haptics Applications

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    The performance of haptic application is highly sensitive to communication delays and losses of data. It implies several constraints in developing networked haptic applications. This paper describes a new internet protocol called Efficient Transport Protocol (ETP), which aims at developing distributed interactive applications. TCP and UDP are transport protocols commonly used in any kind of networked communication, but they are not focused on real time application. This new protocol is focused on reducing roundtrip time (RTT) and inter packet gap (IPG). ETP is, therefore, optimized for interactive applications which are based on processes that are continuously exchanging data.ETP protocol is based on a state machine that decides the best strategies for optimizing RTT and IPG. Experiments have been carried out in order to compare this new protocol and UDP

    Reflections on security options for the real-time transport protocol framework

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    The Real-time Transport Protocol (RTP) supports a range of video conferencing, telephony, and streaming video ap- plications, but offers few native security features. We discuss the problem of securing RTP, considering the range of applications. We outline why this makes RTP a difficult protocol to secure, and describe the approach we have recently proposed in the IETF to provide security for RTP applications. This approach treats RTP as a framework with a set of extensible security building blocks, and prescribes mandatory-to-implement security at the level of different application classes, rather than at the level of the media transport protocol

    Session Initiation Protocol Attacks and Challenges

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    In recent years, Session Initiation Protocol (SIP) has become widely used in current internet protocols. It is a text-based protocol much like Hyper Text Transport Protocol (HTTP) and Simple Mail Transport Protocol (SMTP). SIP is a strong enough signaling protocol on the internet for establishing, maintaining, and terminating session. In this paper the areas of security and attacks in SIP are discussed. We consider attacks from diverse related perspectives. The authentication schemes are compared, the representative existing solutions are highlighted, and several remaining research challenges are identified. Finally, the taxonomy of SIP threat will be presented

    An Efficient Transport Protocol for delivery of Multimedia An Efficient Transport Protocol for delivery of Multimedia Content in Wireless Grids

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    A grid computing system is designed for solving complicated scientific and commercial problems effectively,whereas mobile computing is a traditional distributed system having computing capability with mobility and adopting wireless communications. Media and Entertainment fields can take advantage from both paradigms by applying its usage in gaming applications and multimedia data management. Multimedia data has to be stored and retrieved in an efficient and effective manner to put it in use. In this paper, we proposed an application layer protocol for delivery of multimedia data in wireless girds i.e. multimedia grid protocol (MMGP). To make streaming efficient a new video compression algorithm called dWave is designed and embedded in the proposed protocol. This protocol will provide faster, reliable access and render an imperceptible QoS in delivering multimedia in wireless grid environment and tackles the challenging issues such as i) intermittent connectivity, ii) device heterogeneity, iii) weak security and iv) device mobility.Comment: 20 pages, 15 figures, Peer Reviewed Journa

    Reinterpreting the transport protocol stack to embrace ossification

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    Ubiquitous deployment of middleboxes has resulted in ossification of the transport layer, with TCP and UDP becoming part of the narrow waist of the Internet. This is a necessary stage in the evolution of the network, caused by its progression from research, to production, to increasingly critical infrastructure. New transport layer protocols will be needed in future, but since we are working with essential infrastructure, we cannot expect to have scope to make wholesale rapid changes. Future development must be done using the existing protocols as substrates, always maintaining on-the-wire compatibility. To advance, we must embrace the ossification of the network, and learn to reinterpret and extend the existing protocols
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