High-speed Transport Protocols Research Articles

Online autogenerated congestion control for high‐speed transfer over high BDP networks

With the exponential growth of network bandwidth and application requirements, the existing transmission control protocols have led to the issues of efficiency and applicability. In order to solve the network utility issues and accelerate the data delivery legitimately, the swift and self-learned transmission methods have attracted attention gradually due to its adaptability and predictability. In this research, we propose a high-speed transport protocol, called Hita, based on network performance learning framework to cope with high-speed transfer challenge over high bandwidth delay product networks. The key idea of Hita is to select preferable network performance metrics to reflect network property variability and build corresponding window control model. The proposed protocol, which adopts the online-learning methods, establishes the relation model between the transmission performance metrics and the corresponding congestion window. Afterwards, by determining the direction of window adjustment, the optimal sending window size can be predicted and approached quickly. Numerical results show that Hita can use the limited bandwidth more adequately. For simulation experiments, Hita achieves higher throughput while maintaining a lower packet delay comparing with other protocols. Moreover, Hita shows good performance in terms of intra-protocol fairness, friendliness and protocol stability. For real-world network experiments, Hita achieves more throughput than the other high-speed protocols as well.

Combining explicit admission control and congestion control for predictable data transfers in grids

To improve the Grid infrastructure’s efficiency, the co-reservation of distributed resources is often required. Therefore, Grid applications need to move large amounts of data between these resources within deterministic time frames. In most cases it is possible to specify the volume and the deadline in advance. This paper proposes an approach for data-movement management and bandwidth reservation in Grid, which provides a high acceptance probability of flows in the network while maintaining efficient network-resource utilization. To achieve this, our proposal combines explicit admission control and high-speed transport protocols to enable an opportunistic sharing of the capacity by flows having heterogeneous bandwidth and delay requirements. We formulate the problem and discuss several objective functions. Then we present different heuristics and evaluate them according to the request’s acceptance rate and the network’s utilization metrics. Our simulations include all the communication and computation overheads which are involved in such data transfers.

A Research Framework for Analyzing High Speed Transport Protocols Based on Control-theory

In the recent years, several transport protocols have been proposed for very high bandwidth-delay product networks. However, little is known about the performance of these new mechanisms as well as the interaction with other elements of the network (such as the RED queue management). On the other hand, the control-theoretic approach has proved to be a very useful tool in order to get analytical insight into the performance of congestion control algorithms. In this paper, a control-theoretic research framework is designed and implemented for analyzing high speed transport protocol proposals in network environments with RED active queue management. As a case study, a comprehensive control-theoretic analysis of a promising proposal, namely the HighSpeed TCP is provided. The main contributions of this paper are the following. First, we provide a fluid-flow model for HighSpeed TCP/RED networks. Second, a comprehensive and systematic implementation methodology is described in detail, and a Simulink-based framework is designed for analyzing fluid-based models. Third, we derive a stability condition for HighSpeed TCP/RED networks. The flow-level results are validated by packet-level simulations conducted in Ns-2. Finally, an extension of the framework is presented that makes it capable of describing the interaction of different transport protocols.

Kyushu-TCP: Improving Fairness of High-Speed Transport Protocols

With the emergence of bandwidth-greedy application services, high-speed transport protocols are expected to effectively and aggressively use large amounts of bandwidth in current broadband and multimedia networks. However, when high-speed transport protocols compete with other standard TCP flows, they can occupy most of the available bandwidth leading to disruption of service. To deploy high-speed transport protocols on the Internet, such unfair situations must be improved. In this paper, therefore, we propose a method to improve fairness, called Kyushu-TCP (KTCP), which introduces a non-aggressive period in the congestion avoidance phase to give other standard TCP flows more chances of increasing their transmission rates. This method improves fairness in terms of the throughput by estimating the stably available bandwidth-delay product and adjusting its transmission rate based on this estimation. We show the effectiveness of the proposed method through simulations.

Deconstructing Network Attached Storage systems

Network Attached Storage (NAS) has been gaining general acceptance, because it can be managed easily and files shared among many clients, which run different operating systems. The advent of Gigabit Ethernet and high speed transport protocols further facilitates the wide adoption of NAS. A distinct feature of NAS is that NAS involves both network I/O and file I/O. This paper analyzes the layered architecture of a typical NAS and the data flow, which travels through the layers. Several benchmarks are employed to explore the overhead involved in the layered NAS architecture and to identify system bottlenecks. The test results indicate that a Gigabit network is the system bottleneck due to the performance disparity between the storage stack and the network stack. The tests also demonstrate that the performance of NAS has lagged far behind that of the local storage subsystem, and the CPU utilization is not as high as imagined. The analysis in this paper gives three implications for the NAS, which adopts a Gigabit network: (1) The most effective method to alleviate the network bottleneck is increasing the physical network bandwidth or improving the utilization of network. For example, a more efficient network file system could boost the NAS performance. (2) It is unnecessary to employ specific hardware to increase the performance of the storage subsystem or the efficiency of the network stack because the hardware cannot contribute to the overall performance improvement. On the contrary, the hardware methods could have side effect on the throughput due to the small file accesses in NAS. (3) Adding more disk drives to an NAS when the aggregate performance reaches the saturation point can only contribute to storage capacity, but not performance. This paper aims to guide NAS designers or administrators to better understand and achieve a cost-effective NAS.

A novel high speed transport protocol based on explicit virtual load feedback

Since traditional TCP congestion control is ill-suited for high speed networks, designing a high speed replacement for TCP has become a challenge. From the simulations of some existing high speed protocols, we observe that these high speed protocols make the round-trip time bias problem and the multiple-bottleneck bias problem more serious than for standard TCP. To address these problems, we apply the population ecology theory to design a novel congestion control algorithm. By analogy, we treat the network flows as the species in nature, the sending rates of the flows as the population number, and the bottleneck bandwidth as the food resources. Then we extend the construction method of population ecology models to design a control model, and implement the corresponding end-to-end protocol with virtual load factor feedback, which is called Explicit Virtual Load Feedback TCP (EVLF-TCP). The virtual load factor is computed based on the information of the bandwidth, the aggregate incoming traffic and the queue length in routers, and then senders adjust the sending rate based on the virtual load factor. Theoretical analysis and simulation results validate that EVLF-TCP achieves high utilization, fair bandwidth allocation independent of round-trip time, and near-zero packet drops. These characteristics are desirable for high speed networks.

S-shaped TCP: A transport protocol for improving the performance of TCP in fast long-distance networks

It is well known that TCP does not fully utilize the available bandwidth in fast long-distance networks. This paper proposes S-shaped TCP (SS-TCP). The window growth function of SS-TCP is, in the steady state condition, S-shaped, and it can be divided into three regions. In region I, the window growth rate of SS-TCP is the same as that of standard TCP (STD-TCP). In region II, the window of SS-TCP grows faster than that of STD-TCP. In region III, SS-TCP decreases its window growth rate as the network is becoming congested. This paper also proposes SS-TCPW, an enhanced version of SS-TCP. It makes an end-to-end estimation of the available bandwidth as TCP Westwood+. Based on the estimation, SS-TCPW determines the boundary of region III, and decreases its window size. We evaluate the performance of SS-TCP and SS-TCPW in terms of the metrics that are important for high speed transport protocols; buffer requirement, TCP friendliness, RTT fairness and convergence time. The results showed that SS-TCP has much better performance than HighSpeed TCP (HS-TCP) in terms of buffer requirement and RTT fairness. SS-TCPW has better performance than HS-TCP and SS-TCP in all metrics. The results also clarified that SS-TCP and SS-TCPW have much better TCP friendliness than FAST-TCP.

Performance Evaluation and Comparison of Transport Protocols for Fast Long-Distance Networks

It is well known that TCP does not fully utilize the available bandwidth in fast long-distance networks. To solve this scalability problem, several high speed transport protocols have been proposed. They include Highspeed TCP (HS-TCP), Scalable TCP (S-TCP), Binary increase control TCP (BIC-TCP), and H-TCP. These protocols increase (decrease) their window size more aggressively (slowly) compared to standard TCP (STD-TCP). This paper aims at evaluating and comparing these high speed transport protocols through computer simulations. We select six metrics that are important for high speed protocols; scalability, buffer requirement, TCP friendliness, TCP compatibility, RTT fairness, and responsiveness. Simulation scenarios are carefully designed to investigate the performance of these protocols in terms of the metrics. Results clarify that each high speed protocol successfully solves the problem of STD-TCP. In terms of the buffer requirement, S-TCP and BIC-TCP have better performance. For TCP friendliness and compatibility, HS-TCP and H-TCP offer better performance. For RTT fairness, BIC-TCP and H-TCP are superior. For responsiveness, HS-TCP and H-TCP are preferred. However, H-TCP achieves a high degree of fairness at the expense of the link utilization. Thus, we understand that all the proposed high speed transport protocols have their own shortcomings. Thus, much more research is needed on high speed transport protocols.

HSTP: A high speed transport protocol based on ATM networks

With the rapid development of high speed network such as ATM, traditional transport protocols such as TCP cannot take advantage of the capacity of modern network hardware. A new transport protocol based on ATM, called HSTP (high speed transport protocol), was proposed. The details of HSTP are described. Performance measurements of HSTP, ATM, TCP in the testbed are presented. The protocol provides low latency data transport services for applications on NOW by selective repeat, periodic state exchange, hybrid acknowledgements, using simple buffer and timer management strategies, copy avoidance, block transport for bulk data, and so on.

High-performance protocol architecture

The development of high-speed networking applications requires improvements to data communication protocols in order to efficiently provide the required services to the applications. In this survey paper, we will first give a rapid presentation of protocol optimization techniques and of some high-speed transport protocols developed for specific application needs. We will then present a new protocol architecture based on the “Application Level Framing” (ALF) and “Integrated Layer Processing” (ILP) concepts. ALF states that applications send data as a sequence of autonomous “frames”, which will be at the same time the unit of transmission, the unit of control and the unit of processing. This allows for efficient design of application specific protocols. It also enables ILP, i.e., the integration of multiple transmission control layers in a single loop, maximizing the efficiency of modern processors. We will present both the architectural design aspects and the corresponding implementation problems. Practical experimentations with ALF and ILP will also be described and their benefits and limitations assessed. We will also present a new approach to network architecture namely the active networks approach, and discuss its pros and cons.

Specification and analysis of the SNR high-speed transport protocol

The emergence of optical fiber and its correspondingly high data rates have led to the development of much higher speed networks, both locally and over the long haul. These developments led to the design of new transport protocols, which were intended to take advantage of the high-speed networks. A number of these so-called "high-speed transport protocols" have been designed to date. This paper considers one of these, called the SNR protocol, in detail. A formal specification of the protocol is presented, using the protocol model systems of communicating machines, and the protocol is then analyzed through the specification. An implementation of the protocol based on this formal definition has also been made, and used to simulate the protocol, providing further insights into its performance. Based on the combined results of the analysis and the simulated protocol, a high degree of confidence is gained in the correctness of the protocol. The specification is quite detailed, and from it an implementation should be fairly straightforward. The paper also discusses the difficulties encountered during the analysis of such a complex protocol, and suggests some possible solutions to these problems. Finally, as a result of this work, we comment on the strengths and weakness of the SNR protocol as a solution to the high-speed transport protocol problem, and make two simple suggestions for improving it.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The MultiStream protocol: a highly flexible high-speed transport protocol

A transport layer protocol designed to meet the wide-ranging needs of high-speed applications is described. A unique feature of this protocol is that its behavior, defined by a set of functions, may be modified dynamically over the life of a connection without loss of reliable data transfer. This property makes the protocol attractive for supporting applications, such as multimedia applications that require different protocol support for different portions of their traffic streams. The protocol has been verified to reliably deliver data and manage connections and to contain no deadlocks or loops. A parallel architecture for implementing the protocol has also been verified. Analysis of a skeleton implementation shows that the protocol has the potential to receive data at a rate of over 150 kpackets/s if 10-MIPS processors are used in the implementation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

High-Speed Transport Protocols: Design and Implementation Issues

With the coming of age of fibre-optic technology, data rates of 100 Mb/s are becoming common in local area and even wide area networks. To make such bandwidths available to applications, efficient ...

Performance analysis of MSP: feature-rich high-speed transport protocol

A performance analysis of the MultiStream Protocol (MSP), a feature-rich flexible transport protocol designed to meet the needs of high-performance applications, is presented. The analysis presents the advantages and disadvantages of the implementation of several different protocol mechanisms, such as packet or block mode data transfer. It is based on the processing complexity associated with executing each protocol function. Results show that a feature-rich transport protocol can be implemented in which the protocol control processing overhead is not prohibitive to providing high performance to an application. Instead, the benefits of a lean protocol are achieved because the protocol services better fit application requirements. Also, the primary bottleneck for data transfer is shown to be the complexity associated with error control, which can reduced through the technique of transmitting packets in blocks.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Architectures, features, and implementation of high-speed transport protocols

The results of a literature survey of the characteristics of high-speed protocols, new protocol architectures, and implementation techniques for these protocols are presented. A general description of transport protocol services is followed by a small sample of gigabit applications that might utilize a high-speed network. The applications considered are distributed processing, full-motion video, video-on-demand, and computer imaging. The problems with current transport protocols and protocol architectures are examined. General concepts for high-speed protocols and protocol architectures are presented. Specific design techniques suggested for high-speed protocols and the potential impacts of each are discussed, covering connection management data transfer, buffer management, and functionality. >

Design and implementation of a high-speed transport protocol

The design, analysis, and implementation of an end-to-end transport protocol that is capable of high throughput consistent with the evolving high-speed physical networks based on fiber-optic transmission lines and high-capacity switches are presented. Unlike current transport protocols in which changes in control/state information are exchanged between the two communicating entities only when some significant event occurs, this protocol exchanges relevant and full state information periodically and frequently. It is shown that this reduces the complexity of protocol processing by removing many of the procedures required to recover from network inadequacies such as bit errors, packet loss, and out-of-sequence packets and makes it more amenable to parallel processing. Also, to increase channel utilization in the presence of high-speed, long-latency networks and to support diagrams, and efficient implementation of the selective repeat method of error control is incorporated in the protocol. An implementation using a Motorola 68030-based multiprocessor as a front-end processor is described. The current implementation can comfortably handle 10-15 kpackets/s.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A high speed transport protocol for datagram/virtual circuit networks

We present a design and preliminary analysis of an end-to-end transport protocol that is capable of high throughput consistent with the evolving wideband physical networks based on fiber optic transmission lines and high capacity switches. Unlike the current transport protocols in which changes in control state information are exchanged between the two communicating entities only when some significant event occurs, our protocol exchanges relevant and full state information periodically, routinely and frequently. We show that this results in reducing the complexity of protocol processing by removing many of the procedures required to recover from the inadequacies of the network such as bit-errors, packet loss, out of sequence packets and makes it more amenable to parallel processing. Also, to increase channel utilization in the presence of high speed, long latency networks, and to support datagrams, we propose an efficient implementation of selective repeat method of error control used in our protocol. Thus, we utilize small extra bandwidth to simplify protocol processing; a trade-off that appears proper since electronic speeds for protocol processing are far slower than fiber transmission rates. Our preliminary estimates indicate that 20,000 packets/second can be handled in a completely software implementation on a 10 MIP microprocessor using 8% of its cycles.