Interconnecting Smart Objects with IP: The Next Internet explains why the Internet Protocol (IP) has become the protocol of choice for smart object networks. IP has successfully demonstrated the ...ability to interconnect billions of digital systems on the global Internet and in private IP networks. Once smart objects can be easily interconnected, a whole new class of smart object systems can begin to evolve. The book discusses how IP-based smart object networks are being designed and deployed. The book is organized into three parts. Part 1 demonstrates why the IP architecture is well suited to smart object networks, in contrast to non-IP based sensor network or other proprietary systems that interconnect to IP networks (e.g. the public Internet of private IP networks) via hard-to-manage and expensive multi-protocol translation gateways that scale poorly. Part 2 examines protocols and algorithms, including smart objects and the low power link layers technologies used in these networks. Part 3 describes the following smart object network applications: smart grid, industrial automation, smart cities and urban networks, home automation, building automation, structural health monitoring, and container tracking. * Shows in detail how connecting smart objects impacts our lives with practical implementation examples and case studies * Provides an in depth understanding of the technological and architectural aspects underlying smart objects technology * Offers an in-depth examination of relevant IP protocols to build large scale smart object networks in support of a myriad of new services
IPv6 was introduced in 1994 and has been in development at the IETF for over 10 years. It has now reached the deployment stage. KAME, the de-facto open- source reference implementation of the IPv6 ...standards, played a significant role in the acceptance and the adoption of the IPv6 technology. The adoption of KAME by key companies in a wide spectrum of commercial products is a testimonial to the success of the KAME project, which concluded not long ago. This book is the first and the only one of its kind, which reveals all of the details of the KAME IPv6 protocol stack, explaining exactly what every line of code does and why it was designed that way. Through the dissection of both the code and its design, the authors illustrate how IPv6 and its related protocols have been interpreted and implemented from the specifications. This reference will demystify those ambiguous areas in the standards, which are open to interpretation and problematic in deployment, and presents solutions offered by KAME in dealing with these implementation challenges. * Covering a snapshot version of KAME dated April 2003 based on FreeBSD 4.8 * Extensive line-by-line code listings with meticulous explanation of their rationale and use for the KAME snapshot implementation, which is generally applicable to most recent versions of the KAME IPv6 stack including those in recent releases of BSD variants * Numerous diagrams and illustrations help in visualizing the implementation * In-depth discussion of the standards provides intrinsic understanding of the specifications
Host-to-Host Congestion Control for TCP Afanasyev, Alexander; Tilley, Neil; Reiher, Peter ...
IEEE Communications surveys and tutorials,
01/2010, Letnik:
12, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The Transmission Control Protocol (TCP) carries most Internet traffic, so performance of the Internet depends to a great extent on how well TCP works. Performance characteristics of a particular ...version of TCP are defined by the congestion control algorithm it employs. This paper presents a survey of various congestion control proposals that preserve the original host-to-host idea of TCP-namely, that neither sender nor receiver relies on any explicit notification from the network. The proposed solutions focus on a variety of problems, starting with the basic problem of eliminating the phenomenon of congestion collapse, and also include the problems of effectively using the available network resources in different types of environments (wired, wireless, high-speed, long-delay, etc.). In a shared, highly distributed, and heterogeneous environment such as the Internet, effective network use depends not only on how well a single TCP-based application can utilize the network capacity, but also on how well it cooperates with other applications transmitting data through the same network. Our survey shows that over the last 20 years many host-to-host techniques have been developed that address several problems with different levels of reliability and precision. There have been enhancements allowing senders to detect fast packet losses and route changes. Other techniques have the ability to estimate the loss rate, the bottleneck buffer size, and level of congestion. The survey describes each congestion control alternative, its strengths and its weaknesses. Additionally, techniques that are in common use or available for testing are described.
Smart devices equipped with multiple network interfaces are becoming commonplace. Nevertheless, even though multiple interfaces can be used to connect to the Internet, their capabilities have not ...been fully utilized yet because the default TCP/IP stack supports only a single interface for communication. This situation is now changing due to the emergence of multipath protocols on different network stack layers. For example, many IP level approaches have been proposed utilizing tunneling mechanisms for hiding multipath transmission from the transport protocols. Several working groups under IEEE and IETF are actively standardizing multipath transmission on the link layer and transport layer. Application level approaches enable multipath transmission capability by establishing multiple transport connections and distributing data over them. Given all these efforts, it is beneficial and timely to summarize the state-of-the-art, compare their pros and cons, and discuss about the future directions. To that end, we present a survey on multipath transmission and make several major contributions: 1) we present a complete taxonomy pertaining to multipath transmission, including link, network, transport, application, and cross layers; 2) we survey the state-of-the-art for each layer, investigate the problems that each layer aims to address, and make comprehensive assessment of the solutions; and 3) based on the comparison, we identify open issues and pinpoint future directions for multipath transmission research.
In this paper, we aim to study networking problems from a whole new perspective by leveraging emerging deep learning, to develop an experience-driven approach, which enables a network or a protocol ...to learn the best way to control itself from its own experience (e.g., runtime statistics data), just as a human learns a skill. We present design, implementation and evaluation of a deep reinforcement learning (DRL)-based control framework, DRL-CC (DRL for Congestion Control), which realizes our experience-driven design philosophy on multi-path TCP (MPTCP) congestion control. DRL-CC utilizes a single (instead of multiple independent) agent to dynamically and jointly perform congestion control for all active MPTCP flows on an end host with the objective of maximizing the overall utility. The novelty of our design is to utilize a flexible recurrent neural network, LSTM, under a DRL framework for learning a representation for all active flows and dealing with their dynamics. Moreover, we, for the first time, integrate the above LSTM-based representation network into an actor-critic framework for continuous (congestion) control, which leverages the emerging deterministic policy gradient to train critic, actor, and LSTM networks in an end-to-end manner. We implemented DRL-CC based on the MPTCP implementation in the Linux kernel. The experimental results show that 1) DRL-CC consistently and significantly outperforms a few well-known MPTCP congestion control algorithms in terms of goodput without sacrificing fairness, 2) it is flexible and robust to highly-dynamic network environments with time-varying flows, and 3) it is friendly to regular TCP.
Over the years, the Internet has been enriched with new available communication technologies, for both fixed and mobile networks and devices, exhibiting an impressive growth in terms of performance, ...with steadily increasing available data rates. The Internet research community has kept trying to evolve the transport layer protocols to match the capabilities of modern networks, in order to fully reap the benefits of the new communication technologies. This paper surveys the main novelties related to transport protocols that have been recently proposed, identifying three main research trends: (i) the evolution of congestion control algorithms, to target optimal performance in challenging scenarios, possibly with the application of machine learning techniques; (ii) the proposal of brand new transport protocols, alternative to the Transmission Control Protocol (TCP) and implemented in the user-space; and (iii) the introduction of multipath capabilities at the transport layer.
Every year millions of people around the world suffer from joint and bone diseases and require orthopaedic surgery. Owing to its unique properties such as biocompatibility and ability to bond bones ...with orthopaedic implants, poly methyl-methacrylate (PMMA) is among the most widely used polymer composites for bone cements in orthopaedic and trauma surgery. On the other hand, this material is characterized by low mechanical properties, which can lead to accelerated implant loosening in aggressive environments, such as the human body. Over the years, researchers have studied PMMA, especially its failure mechanism. Various additives to PMMA have been proposed to enhance the mechanical properties of this material. This study investigated the effect of mixing PMMA with α-TCP (PMMA/α-TCP bone cement composite) and β-TCP (PMMA/β-TCP bone cement composite) on its mechanical properties. The study was conducted on commercially available PMMA (Haraeus Palamed) mixed with α-TCP and β-TCP in different concentrations. TCP has bacteriostatic properties and, as a bone compatible material, it stimulates bone regeneration and bone ingrowth, which highly increases the survival rate of PMMA bonding. However, the addition of particles to PMMA can affect mechanical properties of bone cements. In this study, the effects of 0, 1, 2, 3, 5, 8 and 10% dry mass concentration of TCP in bone cement on the mechanical properties of PMMA were investigated. Samples were subjected to compressive loading. This loading mode is typical of the human body after joint prosthesis implantation. The analysis involved comparing selected mechanical parameters of samples prepared according to manufacturer’s instructions and of samples prepared with the addition of α-TCP and β-TCP. Results demonstrated that the addition of β-TCP, whose crystals are triangular, did not affect the mechanical properties of PMMA. On the other hand, the addition of more than 3% dry mass α-TCP, the inner structure of which is hexagonal, led to a slight yet significant decrease in the compressive strength of PMMA.
Despite many years of improvements to it, TCP still suffers from an unsatisfactory performance. For services dominated by short flows (e.g., web search and e-commerce), TCP suffers from the flow ...startup problem and cannot fully utilize the available bandwidth in the modern Internet: TCP starts from a conservative and static initial window ( IW , 2-4 or 10), while most of the web flows are too short to converge to the best sending rate before the session ends. For services dominated by long flows (e.g., video streaming and file downloading), the congestion control ( CC ) scheme manually and statically configured might not offer the best performance for the latest network conditions. To address these two challenges, we propose TCP-RL , which uses reinforcement learning ( RL ) techniques to dynamically configure IW and CC in order to improve the performance of TCP flow transmission. Basing on the latest network conditions observed at the server side of a web service, TCP-RL dynamically configures a suitable IW for short flows through group-based RL , and dynamically configures a suitable CC scheme for long flows through deep RL . Our extensive experiments show that for short flows, TCP-RL can reduce the average transmission time by about 23%; and for long flows, compared with the performance of 14 CC schemes, TCP-RL 's performance ranks top 5 for about 85% of the 288 given static network conditions, whereas for about 90% of conditions, its performance drops by less than 12% compared with that of the best-performing CC schemes for the same network conditions.
Congestion control (CC) has a significant influence on the performance of transmission control protocol (TCP) connections. Over the last three decades, many researchers have extensively studied and ...proposed a multitude of enhancements to standard TCP CC. However, this topic still inspires both academic and industrial research communities due to the change in Internet application requirements and the evolution of Internet technologies. The standard TCP CC infers network congestion based on packet loss events which leads to long queuing delay when bottleneck buffer size is large. A promising solution to this problem is to use the delay signal (RTT or one-way delay measurements) to infer congestion earlier and react to the congestion before the queuing delay reaches a high value. In this survey paper, we describe the delay signal and the algorithms that completely or partially utilize this type of signal. Additionally, we illustrate standard CC and modern active queue management (AQM) principles and discus the interaction between AQM and the delay signal.
Transmission Control Protocol
(TCP) is the most commonly
used transport protocol on the Internet. All indications assure
that mobile computers and their wireless communication links will
be an ...integral part of the future internetworks. In this paper, we
present how regular TCP is well tuned to react to packet loss in
wired networks. We then define mobility and the problems associated
with it. We discuss why regular TCP is not suitable for mobile
hosts and their wireless links by providing simulation results that
demonstrate the effect of the high bit error rates of the wireless
link on TCP performance. We discuss and illustrate the problems
caused by the mobility of hosts using a graph tracing packets
between fixed and mobile hosts. We then present a survey of the
research done to improve the performance of TCP over mobile
wireless networks. We classify the proposed solutions into three
categories: link layer, end-to-end and split. We discuss the
intuition behind each solution and present example protocols of
each category. We discuss the protocols functionality, their
strengths and weaknesses. We also provide a comparison of the
different approaches in the same category and on the category
level. We conclude this survey with a recommendation of the
features that need to be satisfied in a standard mobile TCP
protocol.
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