Datagram Congestion Control Protocol Research Articles

Efficient video transmission—a critical review of various protocols and strategies

ABSTRACT With the advent of 3D video technology and ultra-high-definition (UHD) displays, traditional video coding methods and network/transport protocols seem to fail. This necessitates optimizations at multiple levels and layers: codec-level, system-level, and different layers in the TCP/IP suite. We critically analyze various protocols at different layers in the TCP/IP suite and compare them for various applications. Moreover, the importance of devising intelligent behavior-based strategies at the server side is highlighted. Furthermore, roles and advantages of cross-layer optimization in video transmission are given. The importance of datagram congestion control protocol (DCCP) in an efficient video transmission in the coming years is unfolded. We demonstrate the importance of devising good strategies at the server side in saving the bandwidth. To the best of the knowledge of the authors, this is the first paper that elaborates on DCCP and its significance for the future. In this article, besides analyzing various protocols and discussing optimizations, etc., the value-added suggestions on how to make improvements at various levels are presented. Thus, this work is a one-stop source of information for researchers working on this topic.

A lightweight reliability mechanism proposed for datagram congestion control protocol over wireless multimedia sensor networks

AbstractTransmission of multimedia data over wireless multimedia sensor networks (WMSNs) is a challenging task and requires an effective design for the transport layer protocols to meet both the resource‐constrained WMSN and the requirements of multimedia streaming. The standard transport layer protocols (eg, UDP, TCP, SCTP, and DCCP) have been shown inefficient to transport multimedia data over WMSN without modification in the design of end‐to‐end (ETE) reliability and the congestion control mechanisms. This paper proposed a lightweight reliability mechanism for datagram congestion control protocol (LW‐DCCP) over WMSNs. The lightweight reliability mechanism consists of caching and retransmission algorithms that consider the resource‐constrained WMSNs and the requirements of video streaming over WMSN. Moreover, this paper presents an important modification to TCP‐friendly rate control congestion control mechanism that calculates the loss interval based on intracoded frame sending time. The LW‐DCCP has been evaluated through comprehensive simulation experiments and compared with baseline transport protocols using the 2 frameworks (Eval‐SCTP and Eval‐DCCP) that we developed in NS‐2 environment. The experimental results show that LW‐DCCP ensures effective congestion control and ETE reliability for video transmission over WMSN. In addition, LW‐DCCP experiences better performance in terms of energy consumption, ETE delay, jitter delay, frame delivery ratio, frame peak signal‐to‐noise ratio, and visual quality of the received video as compared to the baseline transport layer protocols.

Performance Evaluation of TCP and DCCP Protocols in Mobile Ad-Hoc Networks (MANETS)

Flow control, end-to-end (EED) delay, throughput, and energy consumptions are important factors of real-time and multimedia communication in mobile ad-hoc networks (MANET’s). It has a characteristic of the dynamic flow of data communication among the various users without using wired technologies. Due to this dynamic structure of MANNETS, most of its energy is consumed in route searching and packet retransmission. In addition, a problem of energy consumption may also occur due to network congestion and traffic flow control. In general, UDP is used for real-time communication but this protocol is unable to control the traffic flow properly. Therefore, a new protocol is developed for this purpose called datagram congestion control protocol (DCCP) used in those networks, which has an increasing number of multimedia traffic, and real-time flow. In this research work, major performance metrics with the issue of power usage of the TFRC and TCP like DCCP protocols are evaluated.

Loss Differentiated DCCP-TCP-Like in Wireless Sensor Network

Wireless sensor network is highly unstable as it is error-prone due to temporary interference of nodes like radio channel contention, radio signal and survival rate of nodes. The losses might result from these wireless temporary interferences or from network congestion. The transport protocol should differently react for these two types of losses. Reducing the transmission rate for wireless inference leads to performance degradation of the network. Transport protocol is optimized by reducing the transmission rate only in case of congestion and not if data is lost for other reasons. In the proposed system, sender performs loss-based control, while the receiver is performing delay-based control against the packet losses. Integration of the loss-based and the delay-based control is applied to TCPlike. TCPlike is one of the congestion control mechanism of the Datagram Congestion Control Protocol(DCCP). This receiver assisted method can mitigate the effect of wireless losses and alleviate the timeout effect. This will help to improve the performance of the DCCP without reducing the congestion window unnecessarily.

S-TFRC: An efficient rate control scheme for multimedia handovers

The integration of heterogeneous wireless access technologies has numerous issues for multimedia applications, such as to smoothly continue over new connections without any service disruption during vertical handovers. We propose State-Aware Feedback extension to Datagram Congestion Control Protocol (DCCP) that meets QoS requirements of multimedia applications throughout the handover process. We consider movement of mobile subscribers among heterogeneous access technologies from highly unstable to more stable environment and model their mobility patterns as Uniform, Pareto, and Exponentially distributed. We present detailed analysis on the performance of proposed mechanism in terms of resuming transmissions during the handover process. In particular, we propose Markov model of TFRC capturing TCP timeouts, loss rates, and no-feedback timer expirations. We validate the proposed analytical model through simulations and show that it accurately predicts various congestion events that may happen during the handover process. We then evaluate the performance of S-TFRC via both simulations and analytical model and observe the sender rates and throughputs achieved. We also consider transmission delays and transmission rates as performance metrics and compare performance of S-TFRC with the standard TFRC. Our results show that S-TFRC is capable of providing better QoS to multimedia applications than standard TFRC by significantly reducing transmission delays and provides better throughput to multimedia applications.

Performance Evaluation of TCP, UDP and DCCP Traffic Over 4G Network

Fourth Generation (4G) mobile systems has been used more widely than the older generations 3G and 2G. Among the reasons are that the 4G’s transfer rate is higher and it supports all multimedia functions. Besides, its’ supports for wide geographical locus makes wireless technology gets more advanced. The essential goal of 4G is to enable voice-based communication being implemented endlessly. This study tries to evaluate if the old protocols suit with this new technology. And which one has the best performance and which one has the greatest effect on throughput, delay and packet loss. The aforementioned questions are crucial in the performance evaluation of the most famous protocols (particularly User Datagram Protocol (UDP), Transmission Control Protocol (TCP) and Datagram Congestion Control Protocol (DCCP)) within the 4G environment. Through the Network Simulation-3 (NS3), the performance of transporting video stream including throughput, delay, packet loss and packet delivery ratio are analyzed at the base station through UDP, TCP and DCCP protocols over 4G’s Long Term Evaluation (LTE) technology. The results show that DCCP has better throughput and lesser delay, but at the same time it has more packet loss than UDP and TCP. Based on the results, DCCP is recommended as a transport protocol for real time video.

Adaptive multimedia streaming using a simulation test bed

The major purpose of this paper is to transmit an existing video above a complete simulated video streaming architecture based on Network Simulator (NS2). Thanks to our architecture, the visual quality evaluation of the distributed streaming platform under various conditions is simplified. Indeed, the received video can be easily visualized using a classic video client or be compared using the Peak Signal-Noise Ratio (PSNR) value and the Structural SIMilarity (SSIM) value. In the case study, we compare adaptive video congestion strategies using a transcoder, Datagram Congestion Control Protocol (DCCP) and TCP-Friendly Rate Control (TFRC).

Packet Scheduling and Congestion Control Schemes for Multipath Datagram Congestion Control Protocol

Packet Scheduling and Congestion Control Schemes for Multipath Datagram Congestion Control Protocol

A Cross-layer Loss Discrimination Scheme for DCCP over the Wireless Network

DCCP (Datagram Congestion Control Protocol) is a transport layer protocol that provides congestion control for unreliable data transmission. The congestion control mechanism embedded in DCCP adjusts the packet sending rate according to network condition. However, DCCP does not discriminate congestion losses and wireless link errors resulted from fading and thus it leads to unnecessary rate adjustment. In this paper, we proposed a mechanism to enhance bandwidth utilization of DCCP over wireless network. We employed a cross-layer loss discrimination scheme to distinguish congestion loss and fading loss. The cross-layer based mechanism detects frame loss in the data link layer in real-time to infer the actual fading loss rate. Thereafter, the fading loss can be excluded from the packet loss observed in the transport layer. Once the accurate congestion loss rate is calculated, the sender can make appropriate adjustment on the transmission rate that reflects the current congestion state along the transmitting path using the DCCP rate control procedure. Simulation results show that DCCP with our proposed CCID 3 rate control scheme can discriminate fading loss and achieve from 4.7% to 15.5% improvement on transmission throughput when the fading loss rate varies from 5% to 15% in wireless network.

Distortion-Aware Scalable Video Streaming to Multinetwork Clients

<?Pub Dtl=""?> We consider the problem of scalable video streaming from a server to multinetwork clients over heterogeneous access networks, with the goal of minimizing the distortion of the received videos. This problem has numerous applications including: 1) mobile devices connecting to multiple licensed and ISM bands, and 2) cognitive multiradio devices employing spectrum bonding. In this paper, we ascertain how to optimally determine which video packets to transmit over each access network. We present models to capture the network conditions and video characteristics and develop an integer program for deterministic packet scheduling. Solving the integer program exactly is typically not computationally tractable, so we develop heuristic algorithms for deterministic packet scheduling, as well as convex optimization problems for randomized packet scheduling. We carry out a thorough study of the tradeoff between performance and computational complexity and propose a convex programming-based algorithm that yields good performance while being suitable for real-time applications. We conduct extensive trace-driven simulations to evaluate the proposed algorithms using real network conditions and scalable video streams. The simulation results show that the proposed convex programming-based algorithm: 1) outperforms the rate control algorithms defined in the Datagram Congestion Control Protocol (DCCP) by about 10–15 dB higher video quality; 2) reduces average delivery delay by over 90% compared to DCCP; 3) results in higher average video quality of 4.47 and 1.92 dB than the two developed heuristics; 4) runs efficiently, up to six times faster than the best-performing heuristic; and 5) does indeed provide service differentiation among users.

A DCCP Variant for High Speed Networks

The Datagram Congestion Control Protocol (DCCP) protocol was proposed to provide a great variety of functionality to real-time applications. Its congestion control mechanisms were defined to be friendly to the TCP-Reno, which makes its operation inappropriate to high speed networks. In this paper, a variant of the DCCP, called FAST DCCP, is proposed to overcome such deficiency. As evidenced by experimental evaluation as well as by simulation, the new protocol scales with the increase of network capacity.

On the quality of VoIP with DCCP for satellite communications

SUMMARYWe present experimental results for the performance of selected voice codecs using Datagram Congestion Control Protocol (DCCP) with CCID4 congestion control over a satellite link. We evaluate the performance of both constant and variable data rate speech codecs for a number of simultaneous calls using the ITU E‐model. We analyse the sources of packet losses and additionally analyse the effect of jitter, which is one of the crucial parameters contributing to Voice over IP (VoIP) quality and has, to the best of our knowledge, not been considered previously in the published DCCP performance results. We propose modifications to the CCID4 algorithm and demonstrate how these improve the VoIP performance, without the need for additional link information other than what is already monitored by CCID4. We also demonstrate the fairness of the proposed modifications to other flows. Although the recently adopted changes to TCP‐Friendly Rate Control specification alleviate some of the performance issues for VoIP on satellite links, we argue that the characteristics of commercial satellite links necessitate consideration of further improvements. We identify the additional benefit of DCCP when used in VoIP admission control mechanisms and draw conclusions about the advantages and disadvantages of the proposed DCCP/CCID4 congestion control mechanism for use with VoIP applications. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Improved video streaming scheme for internet television with broadband wireless access

Internet television video–streaming schemes do not respond well when access is through a broadband wireless link. A simple but effective negative acknowledgment–based scheme has been designed to meet the needs of Internet television. When used with broadband wireless access, simulations show that the scheme has the better features of both raw UDP transport and the standardised Datagram Congestion Control Protocol but does not have those protocols' disadvantages. The delivered video quality is also found to be superior to multiple–connection, congestion–controlled streaming. This is important for mobile video delivery, as video quality is a key determinant of customer choice.

Wireless Transport Layer Congestion Control Evaluation

The performance of transport layer protocols can be affected differently due to wireless congestion, as opposed to network congestion. Using an active network evaluation strategy in a real world test-bed experiment, the Transport Control Protocol (TCP), Datagram Congestion Control Protocol (DCCP), and Stream Control Transport Protocol (SCTP) were evaluated to determine their effectiveness in terms of throughput, fairness, and smoothness. Though TCP’s fairness was shown to suffer in wireless congestion, the results showed that it still outperforms the alternative protocols in both wireless congestion, and network congestion. In terms of smoothness, the TCP-like congestion control algorithm of DCCP did outperform TCP in wireless congestion, but at the expense of throughput and ensuing fairness. SCTP’s congestion control algorithm was also found to provide better smoothness in wireless congestion. In fact, it provided smoother throughput performance than in the network congestion.

RELD, RTT ECN Loss Differentiation to optimize the performance of transport protocols on wireless networks

One major yet unsolved problem in wired-cum-wireless networks is the classification of losses, which might result from wireless temporary interferences or from network congestion. The transport protocol response to losses should be different for these two cases. If the transmission uses existing protocols like TCP, the losses are always classified as congestion losses by sender, causing reduced throughput. In wired networks, ECN (Explicit Congestion Notification) can be used to control the congestion through active queue management such as RED (Random Early Detection). It can also be used to solve the transport protocol misreaction over wireless networks. This paper proposes a loss differentiation method (RELD), based on ECN signaling and RTT (Round Trip Time), and applied to TCPlike. TCPlike is one of the three current congestion controls present in the new transport protocol DCCP (Datagram Congestion Control Protocol). Our simulations, using a more realistic simulated loss error model for wireless networks, show that RELD optimizes congestion control and therefore increases the performance of transport protocols over wireless networks, leading to an average performance gain ranging from 10% to 15%.

Transport Protocol Throughput Fairness

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.

Application-level QoS: improving video conferencing quality through sending the best packet next

In a traditional network stack, data is transmitted in the order that it is received. An algorithm is proposed where priority of packets and expiry times is used by the transport layer to reorder or discard packets to optimise the use of available bandwidth. This scheme is implemented and compared to unmodified Datagram Congestion Control Protocol (DCCP) using traffic modelled on video conferencing software. The results show improvement can be made during periods of congestion – more audio packets arrive on time and in many cases video packet arrival rates also increase.

DCCP: Transport Protocol with Congestion Control and Unreliability

The datagram congestion control protocol (DCCP) is a new transport protocol standard that the IETF recently proposed. Because DCCP simultaneously features congestion control and unreliable transmission, it's especially suited to multimedia streaming applications and has thus received much attention. This article introduces DCCP's main characteristics and operation.

DCCP partial reliability extension with sequence number compensation

Datagram congestion control protocol (DCCP), possessing congestion control and unreliable transmission, specially suits real-time multimedia applications. Nevertheless, losses of key packets will cause a substantial decline on quality of services (QoS) in some applications. This paper proposes a DCCP partial reliability extension (PR-DCCP) that can retransmit lost packets as needed. Since DCCP uses an incremental sequence number, the retransmitted packets cannot utilize their original sequence number. To solve this problem, PR-DCCP adopts sequence number compensation, which appends an offset to the retransmitted packet; thus the receiver can use the sequence number of this retransmitted packet and the attached offset so as to re-obtain the original sequence number. The simulation uses two performance metrics: decodable frame ratio (DFR) representing QoS, and useless data received ratio (UDRR) representing the bandwidth waste. These are used to evaluate different transport protocols, namely, PR-DCCP, DCCP, SCTP, TCP, and UDP. Simulation results show that PR-DCCP has the better DFR and UDRR than other transport protocols in almost all cases. For various movies, a DFR of PR-DCCP is 1.2-12.4% higher than that of DCCP; while UDRR is lower by 73.2-85.1%. Furthermore, two reliability policies to determine which packets require reliability are investigated. Finally, the comparisons between PR-DCCP and PR-SCTP are examined.

DCCP Congestion Control with Virtual Recovery to Achieve TCP-Fairness

The Datagram Congestion Control Protocol (DCCP) has been standardized by the IETF as an unreliable transport protocol for real-time streaming applications. DCCP features unreliable data delivery and congestion control to achieve timely transmission and to fairly share bandwidth with TCP respectively. However, we found that unfair bandwidth sharing between DCCP and TCP still exists because DCCP does not utilize fast recovery. This paper proposes a novel congestion control for DCCP, called TCP-friendly DCCP (TF-DCCP), which lets DCCP own "virtual recovery" and thus enter congestion avoidance simultaneously with TCP. Simulation results demonstrate that TF-DCCP can provide excellent TCP-fairness.