Multipath Transmission for Wireless Internet Access--From an End-to-End Transport Layer Perspective

SCTP is a transport layer protocol mainly designed for transferring public switched telephone network signalling over IP networks. Some of the protocols that support data transmission are transmission control protocol (TCP), user datagram protocol (UDP), and stream control transmission protocol (SCTP). SCTP is a newly invented reliable, message-oriented transport protocol. It is similar to TCP and UDP with some additional features such as multi-streaming and multi-homing. Even though it is a new protocol with some advanced features, there is a security loophole issue in data transmission using SCTP. Hence, we proposed a new technique to transmit a secret message by hiding it in a secret matrix using the advanced features of SCTP. The simulation of our proposed method provides better performance and high security for secret message transmission against network attacks.

Multipath TCP (MPTCP) is a backward compatible extension of Transmission Control Protocol (TCP) designed to let an application send data over several TCP connections, usually called subflows. MPTCP presents several opportunities over legacy TCP, especially when these subflows follow disjoint paths: for instance bandwidth aggregation or seamless mobility across networks. While MPTCP is built as an extension of TCP, the scope of the modifications qualifies it almost as a new protocol. This means traditional TCP tools are not enough to analyze MPTCP performance. We thus develop and present an open source application able to analyze MPTCP specific metrics such as the aggregated goodput or inter-subflow retransmissions.

Recently, requirement of ubiquitous availability and increase of mobile user driving traffic has become a serious problem. On the other hand, most mobile equipment have more than one network interface and a host can use multiple network interfaces simultaneously with multi-homing technology. Therefore, multiple paths are utilized for data transfer in one pair of terminals. This is a Con-current Multi-path Transfer (CMT). It makes acquire improved bandwidth and resilience just by modifying previous transport layer protocol like TCP (transmission control protocol). TCP is the most common transport layer protocol in Internet applications. Accordingly, IETF have proposed Multi-path TCP (MPTCP) that previous single-TCP with multi-homing technology. However, when transmit the packet using different two path which has dissimilar characteristic simultaneously, there is some throughput degradation compared to single-TCP that shows best performance. The reason is that out-of-ordered packet is generated because each path has different bandwidth, delay and packet loss rate. To solve these problems, this research proposes reordering considered packet scheduling algorithm at the sender. Main idea of the proposed scheme is estimating packet receiving time at the receiver and scheduling packet. By using proposed algorithm, the number of out-of-ordered packet in the receiver buffer is reduced. Therefore, performance degradation is also mitigated especially in the case that asymmetry between two path is severe.

The steadily growing deployment of resilience-critical Internet services is leading to an increasing number of Multi-Homed network sites. Asymmetric Digital Subscriber Lines (ADSL) are an inexpensive way to add a secondary Internet access connection. With the development of Multi-Path Transport Layer protocols - like Multipath TCP (MPTCP) and the Stream Control Transmission Protocol (SCTP) furnished by a Concurrent Multipath Transfer (CMT-SCTP) extension - there is also a strong interest in utilising all access connections simultaneously to improve the data throughput of the applications. However, combining network paths over ADSL with paths over other access technologies like fibre optic links implies highly dissimilar paths with significantly different bandwidths, delays and queuing behaviours. Efficient Multi-Path transport over such dissimilar paths is a challenging task for the new Transport Layer protocols under development. In this paper, we show the difficulties of Multi-Path transport in a real-world dissimilar path setup which consists of a high-speed fibre optic link and an ADSL connection. After that, we present an optimised buffer handling technique which solves the transport efficiency issues in this setup. Our optimisation is first analysed by simulations. Finally, we also show the usefulness of our approach by experimental evaluation in a real Multi-Homed Internet setup.

Recent data centers provide dense inter-connectivity between each pair of servers through multiple paths. These data centers offer high aggregate bandwidth and robustness by using multiple paths simultaneously. Multipath TCP (MPTCP) protocol is developed for improving throughput, fairly sharing network link capacity and providing robustness during path failure by utilizing multiple paths over multi-homed data center networks. Running MPTCP protocol for latency-sensitive rack-local short flows with many-to-one communication pattern at the access layer of multi-homed data center networks creates MPTCP incast problem. In this paper, Balanced Multipath TCP (BMPTCP) protocol is proposed to mitigate MPTCP incast problem in multi-homed data center networks. BMPTCP is a window-based congestion control protocol that prevents constant growth of each worker’s subflow congestion window size. BMPTCP computes identical congestion window size for all concurrent subflows by considering bottleneck Top of Rack (ToR) switch buffer size and increasing count of concurrently transmitting workers. This helps BMPTCP to avoid timeout events due to full window loss at ToR switch. Based on current congestion situation at ToR switches, BMPTCP adjust transmission rates of each worker’s subflow so that total amount of data transmitted by all concurrent subflows does not overflow bottleneck ToR switch buffer. Simulation results show that BMPTCP effectively alleviates MPTCP incast. It improves goodput, reduces flow completion time as compared to existing MPTCP and EW-MPTCP protocols.

Multipath Transmission Control Protocol (MPTCP) is a new transmission protocol designed by The Internet Engineering Task Force (IETF) for multipath transmission. In order to realize the large-scale and rapid deployment of MPTCP, the design of MPTCP needs to ensure fairness with traditional Transmission Control Protocol (TCP). The IETF organization designed a congestion control algorithm for the network fairness of MPTCP, but did not consider the bottleneck fairness of MPTCP. In this paper, we propose a congestion control algorithm based on Dynamic Time Warping (DTW) and Bottleneck Bandwidth and Round-trip time (BBR), which takes the bottleneck fairness in consideration for higher transmission efficiency. The experiments validate that the proposed algorithm can improve the recognition rate of shared bottlenecks, increase bandwidth utilization, and ensure fairness at the bottleneck.

Today's laptops and mobile terminals are equipped with several network interfaces belonging to different access technologies. Users can benefit from multi-homing to access network services anywhere, at any time and from any network. Multipath TCP (MPTCP) is a modified version of Transmission Control Protocol (TCP) which allows a TCP connection to simultaneously send data over multiple paths. One of the objectives of MPTCP is to improve the throughput of TCP connection. A MPTCP connection over multiple paths should achieve a no worse throughput than a single TCP connection over the best constituent path. In this paper, we evaluate the performance of MPTCP in terms of throughput optimization and load sharing. The measurements show that the context of heterogeneous networks (Ethernet, Wifi and 3G) has a great impact on the MPTCP performances and reveal the need of an intelligent algorithm for interface selection in MPTCP.

The growing popularity of mobile devices and Internet of Things (IoT) has inspired the advent of the Cloudlet concept-a "small data center" close to users at the edge. It is believed that the Quality of Experience (QoE) of end users would greatly improve if they can access required resources within a one-hop distance from Cloudlet servers. Over the years, many researchers have proposed using virtual machines (VMs) as such service-provisioning servers. However, seeing the potentiality of containers-a lightweight virtualization tool, this paper adopts LXC containers as Cloudlet platforms. To facilitate container migration between Cloudlets, CRIU (Checkpoint/Restore in Userspace) has been chosen as the migration tool. Since the migration process goes through the Wide Area Network (WAN), which may experience congestion or network failures, this paper adopts the MPTCP (Multipath TCP) protocol to address the challenge. The multiple subflows established within a MPTCP connection can improve the resilience of the migration process and reduce migration time. We have conducted a number of experiments to validate the proposed approach. The experimental results show that LXC containers are suitable candidates for the problem and MPTCP protocol is effective in enhancing the migration process.

Recently, dynamic adaptive streaming over HTTP (DASH) has become an increasingly popular way to view video over the Internet. In particular compared to other video streaming services these DASH approaches deliver superior QoE to viewers. This is due to improved video segment selection. Generally, Transmission Control Protocol (TCP) CUBIC is the defacto transport layer protocol use by DASH. To improve the robustness of the transport layer to network congestion many other TCP variants were implemented such as Compound TCP and BBR. Nevertheless some were made to work specifically in LAN environments for example Agile-SD. However, recently another transport layer protocol User Datagram Protocol (UDP) has been used in Google’s QUIC implementation. To date no work has be found giving the performance of these transport layer protocols with DASH. In this paper we test the performance of Agile-SD, CUBIC, Compound TCP, BBR and QUIC using the BBA, MPC, Pensieve and Oboe DASH approaches. Experiments simulate congested bottleneck link conditions common at household routers where families view multiple videos at the same time. We observe Oboe and Agile-SD is the most promising combination with CUBIC and Pensieve next. However, even though QUIC was touted to have superior transport layer performance by Google it was the worst performing.

The Stream Control Transmission Protocol (SCTP) is a transport layer protocol introduced to complement the well known User Datagram Protocol (UDP) and the Transmission Control Protocol (TCP). The current implementation of SCTP heavily leverages some existing mature techniques from TCP. This paper studies the effect that RTOmin (retransmission timeout minimum) has on the selective acknowledgement (SACK), fast retransmission, and timeout mechanisms. We show that there are optimization opportunities in the manipulation of RTOmin while not significantly affecting timeout values and number of fast retransmissions. We demonstrate that RTOmin plays a balancing role in the trigger of timeouts and fast retransmissions and conclude that a dynamically set RTOmin would yield significant time-to-complete (throughput) improvements for SCTP based applications.

Stream Control Transmission Protocol (SCTP) is the third transport layer protocol next to TCP and UDP. The SCTP provides some distinctive features over the TCP. This paper is purposed to compare SCTP and TCP in the performance perspective. We compare the throughput of SCTP and TCP for the three different test scenarios: the performance comparison of SCTP and TCP for the different size of the user input data for the socket system call, the analysis of the fairness under competition of SCTP and TCP traffic, and the performance comparison of the SCTP multi-homing and single-homing cases. From the results, it is shown that the SCTP provides better throughput over TCP for a larger user input data. We also see that the SCTP traffic tends to compete fairly with TCP and that the multi-homing SCTP provides better performance than the single-homing case.

현재 인터넷에서는 객체를 전송하기 위해 HTTP over TCP가 사용된다. SCTP는 TCP의 문제점을 보완하기 위해 제안된 프로토콜로 개별적인 스트림을 이용하여 데이터를 전송하므로 웹 객체의 평균 응답 시간을 감소시킬 수 있다. 본 논문에서는 HTTP over SCTP의 평균 응답 시간을 추정하는 해석적 모델을 개발함으로써 TCP에 대한 SCTP의 효과를 추정하고자 한다. TCP 지연을 구하기 위한 기존의 해석적 모델이 주로 유선 환경을 가정한데 비해, 본 연구에서 제안하는 모델은 다중 패킷 손실이 발생하고, 빠른 재전송이 가능하지 않은 무선 환경을 가정한다. 추정된 평균 응답 시간은 실제 웹 응용을 개발할 때, 종단 사용자의 서비스 품질을 만족시키기 위한 사전 벤치마크로 사용될 수 있다. 추정 모델의 타당성을 검증하기 위해 테스트베드 상에서 성능 실험을 수행한 결과, 모델과 실험결과의 차이가 평균 6% 이내로 매우 작으며, 동시에 HTTP over SCTP의 평균 전송 시간이 HTTP over TCP의 평균 전송 시간보다 작은 것으로 확인되었다. Hyper text transfer protocol (HTTP) over transmission control protocol (TCP) is currently used to transfer objects in the Internet. Stream control transmission protocol (SCTP), an alternative to TCP, which allows for independent delivery among streams, and can thus reduce the mean response delay of web object. We present an analytical model to find the mean response delay for HTTP over SCTP, therefore, estimate the effectiveness of SCTP over TCP. Typical TCP delay models assume the wired environment. On the contrary, the proposed model in this paper assumes the multiple packet losses and wireless environment where fast retransmission is not possible due to small window. The estimated mean response time can be used the benchmark to meet quality of service (QoS) at end-user. We validate the accuracy of our model using experiments. It is shown that the differences between the results from model and those from experimental are very small below 6 % on average. We also find that the mean response delay for HTTP over SCTP is less than that for HTTP over TCP.

Most current web application use HTTP (Hyper Text Transfer Protocol) and TCP (Transmission Control Protocol) to retrieve objects from the Internet. SCTP (Stream Control Transmission Protocol) is recently proposed transport protocol with congestion control mechanism similar to that of TCP. Waiting delay is an important performance criterion for when transferring web object over the Internet. In this paper, we present an analytical model of mean waiting delay for object transfers over the Internet in a wireless using the SCTP as the transport protocol and compare with the mean waiting in using TCP. Validation of the model using experimental results show that the mean waiting delay for HTTP over SCTP is less than that for HTTP over TCP. This is caused by the small slow-start time of SCTP.

A significant enhancement in recent communication systems is Satellite Communications. The performance improvement of the transmission control protocol (TCP) in satellite communications has been an active research area. Multipath TCP (MPTCP) ensures a robust solution than the regular TCP. However, the performance degradation in satellite networks due to the link asymmetry, high loss and high latency cannot distinguish the packet losses caused by network congestions from the losses properly. In this paper, a round-trip time detection-based algorithm is proposed using available bandwidth estimation (ABE) to mitigate the issue of blind decreasing of congestion window upon detecting the packet loss over lossy satellite networks. Experiments are done using the NS-2 network simulator to compare the various congestion control algorithms of both TCP and MPTCP over satellite networks. Simulations results from the experiments show that our proposed algorithm outperforms the existing algorithms which are mentioned in this article.

The spread of Edge Internet of Things (IoT) radically changes our lifestyle. However, the multimedia services in edge IoT are still stuck by inefficiency. The dynamic typologies perplex the transmission of massive real-time data. To solve this problem, multipath transmission control protocol (MPTCP) which has a natural advantage in transmission robustness and bandwidth aggregation is becoming a good choice. In this paper, failure-aware and delay-predicted multipath virtual queue scheduling (FD-MVQS) is proposed to optimize the MPTCP performance in edge IoT. FD-MVQS constructs a two-plane cooperative scheduling system. In the control plane, the transmission failure estimation and chaos theory-based arrival delay prediction methods are introduced to provide the foundation for prescheduling. In the data plane, the multipath virtual queue scheduling is designed to allocate segments to different subflows. Simulation results showed that the proposed FD-MVQS performed better than standard and typical multipath transmission solutions in throughput, delay, and segment disorder.