User-Controlled Subflow Selection in MPTCP: A Case Study

Multipath Transmission Control Protocol (MPTCP) is an approach towards high-throughput and efficient load balancing over multiple paths. Each of paths forms a TCP connection with an IP address, and those can be implemented as multiple network interfaces or multiple ports within a network interface. In this paper, we focus on the multiple network interfaces environment. Each network interface with an IP address is called as a subflow. A subflow is a TCP connection which can have a different internet path identified by IP addresses of source and destination network interfaces. To control these multiple subflows, MPTCP supports many options. Specifically, to establish a new subflow, MPTCP uses an <monospace>ADD&#x005F;ADDR</monospace> option. A host sends <monospace>ADD&#x005F;ADDR</monospace> option to inform another host of its IP address, and then, the host receiving <monospace>ADD&#x005F;ADDR</monospace> option tries to establish a subflow at the address of <monospace>ADD&#x005F;ADDR</monospace> option. However, by forging the <monospace>ADD&#x005F;ADDR</monospace> option, an attacker can create a fake subflow that passes through itself and eventually hijack the connection between both end hosts. In a previous study, Hash-based Message Authentication (HMAC) was added to the <monospace>ADD&#x005F;ADDR</monospace> option, preventing it from being forged. Nevertheless, since the keys for generating HMAC can be leaked during three-way handshake, a variant of the <monospace>ADD&#x005F;ADDR</monospace> attack called the persistent <monospace>ADD&#x005F;ADDR</monospace> attack can be possible. To this end, we propose a protocol that can prevent the <monospace>ADD&#x005F;ADDR</monospace> attacks by backward confirmation of the <monospace>ADD&#x005F;ADDR</monospace> option without encryption. The main idea of our proposal is to apply a digital signature scheme for the backward confirmation. We show security analysis for the proposed protocol and compare with the previous studies in terms of time/space overheads.

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.

Reducing traffic burstiness for MPTCP in data center networks

MP-TCP (MultiPath-Transmission Control Protocol) was designed to use multiple interfaces in hosts; it uses several subflows (a set of regular TCP connections) to increase the performance compared to TCP. However, when a host has only one network interface but several subflows are created, they follow the same path to their destination generating bottlenecks and MP-TCP advantages are lost. This paper presents a solution to the shared-bottleneck problem using SDN (Software Defined Networking). A plugin for OpenDayLight is developed for implementing Dijkstra's Algorithm to find paths and assign them to new subflows avoiding bottlenecks. The solution supports concurrent MP-TCP connections. Results of tests obtained using the implemented plugin in several topologies are presented.

The number of mobile terminals that have both a cellular interface and a Wi-Fi interface has been growing in the recent years. Meanwhile, Multipath TCP (MPTCP) that enables the simultaneous use of multiple paths with multiple TCP flows while showing just one regular TCP connection with the application has been standardized by the IETF and has drawn more attention recently. One feature of MPTCP is that it can be realized only by operating system layers supporting multipath communication without any modifications of the application. However, it might be difficult to install MPTCP in all server operating systems. In this paper, we propose a method for applying a proxy that forwards TCP communication from a server to MPTCP communication on a mobile core network, and show the results of evaluation with the existing equipment.

Interpath contention is a phenomenon experienced in a MultiPath TCP (MPTCP) connection when its subflows dispute resources of shared bottlenecks in end-to-end paths. Although solutions have been proposed to improve MPTCP performance in different applications, the impact of interpath contention on the multipath performance is little understood. In this paper, we evaluated such phenomenon experimentally in disjoint paths–an ordinary multipath scenario where subflows dispute bottlenecks of paths physically disjointed in a connection. Under several path conditions determined from emulations of capacity, loss, and delay of bottlenecks, we analyzed the influence of MPTCP mechanisms such as packet scheduling, congestion control, and subflow management. Differently from other studies, we observed that the very first influence was caused by the current subflow manager, full-mesh , with dichotomous impact on the multipath performance when establishing several subflows per disjoint path. Experimental results showed that contention among subflows can lead to positive (goodput improvement) or negative (goodput degradation) impacts according to the bottleneck conditions. In certain conditions, simply establishing subflows in single-mesh , with at most one subflow per disjoint path, could avoid interpath contention while improving goodput significantly, by doubling the performance of full-mesh under different conservative congestion controls.

We present TeamBoost, a collaborative solution enabling a client device to leverage the cellular links of its nearby devices to enhance its overall connectivity to the cloud. TeamBoost architecture can serve for numerous internet-of-things (IoT) applications, yet in this work it is proposed as an alternative to conventional and costly H/W upgrades aiming to maintain up-to-date vehicle connectivity experience throughout the vehicles extended lifetime. TeamBoost's approach is to build upon a relatively new and yet well established Multi-Path TCP (MPTCP) protocol, exploiting the natural way that MPTCP splits an end-to-end single TCP stream into multiple MPTCP sub-streams that traverse different communication links. TeamBoost's novel implementation provides a non-trivial extension of MPTCP to TeamBoost's collaborative setting, where sub-streams are relayed through multiple independent devices. To support scalability of the system, the implementation of TeamBoost on the devices is restricted to the user-space, allowing it to be installed as any other application supported by its operating system (OS). Experimental results show the benefits of TeamBoost, in terms of both connectivity performance and robustness.

Network functions virtualization (NFV) offers an alternative way to design, deploy, and manage networking services. This paper presents the implementation and deployment of a virtualized network function to solve MP-TCP’ shared bottlenecks problem. MP-TCP (MultiPath-TCP) is a protocol that allows hosts that have several interfaces to send data through multiple paths in the network. An MP-TCP connection is divided into several TCP connections called subflows that may follow different paths, in this way effective connection rates and resilience can be increased. However, in a scenario where MP-TCP is used with hosts having a single network interface, created subflows follow the same path even if several are available; this generates the problem known as a shared bottleneck. A solution to this problem is implemented as a SDN (Software Defined Networking) module that is integrated into OpenDayLight’s framework which is used as the SDN controller. This solution is then deployed as a NFV over a cloud infrastructure implemented with OpenStack over a high-end physical server. The deployment of the NFV is automated to a certain degree using Ansible, a DevOps tool. Finally, results of the tests of the SDN solution to MP-TCP’s shared bottlenecks and its operation as a NFV using a completely virtualized network are reported.

We present different design options to implement Augmented Multipath Transmission Control Protocol (A- MPTCP) communications via a Locator/Identifier Separation Protocol (LISP) Traffic Engineering (TE) overlay network. MPTCP allows a TCP connection using multiple subflows to maximize resource usage. LISP is a routing and addressing architecture that provides new semantics for IP communications, by separating the device identity (endpoint identifier) from its location (routing locator) using two different numbering spaces. Our proposition is to adopt a LISP overlay network with traffic engineering capabilities to steer MPTCP subflows across wide-area Internet networks. The resulting augmentation consists of a subflow forwarding that can reach edge bottleneck capacity and surround inter-domain transit bottlenecks and inefficient paths. It can be particularly useful for cases where, even if endpoints are single-homed, inter-domain path diversity can be grasped by the LISP-TE network overlay. We specify the different modes at which this augmentation can take place, from stateless and light modes with very limited management in the network, to stateful and advanced modes implementable by a network provider desiring a higher control on the network. Based on extensive experimentation on the worldwide LISP testbed, we show that the achievable gains up 25% in throughput, while identifying required further improvements.

Mobile devices are emerging with multiple interfaces with diverse access technologies. Using multiple interfaces simultaneously can bring lots of benefits to users. Multi-Path TCP is proposed in recent years, which aims to provide the capability for a TCP host to simultaneously use its multiple interfaces to transmit in one TCP connection. However the original MPTCP data scheduling algorithm has some defects and cannot fit multiple kinds of applications to achieve maximize throughput. We thus proposed and implemented an optimized MPTCP data scheduling algorithm. We used the type of service of an application and quality parameters of each interfaces measured in real time to calculate the best path dynamically. The results of the experiment showed that our algorithm had better performance than the original one in achieving higher data throughput, resource utilization and more rationality during an MPTCP transmission.

Today, there is a generalized standard usage of internet for all.The devices via multiple technologies that facilitates to provide few communication methods to scholars to work with. By forming multiple paths in the data center network, latest generation data centers offer maximum bandwidth with robustness. To utilize this bandwidth, it is necessary that different data flows take separate paths. In brief, a single-path transport seems inappropriate for such networks. By using Multipath TCP, we must reconsider data center networks, with a diverse approach as to the association between topology, transport protocols, routing. Multipath TCP allows certain topologies that single path TCP cannot use. In newer generation data centers, Multipath TCP is already deployable using extensively deployed technologies such as Equal-cost multipath routing. But, major benefits will come when data centers are specifically designed for multipath transports. Due to manifold of technologies like Cloud computing, social networking, and information networks there is a need to deploy the number of large data centers. While Transport Control Protocol is the leading Layer-3 transport protocol in data center networks, the operating conditions like high bandwidth, small-buffered switches, and traffic patterns causes poor performance of TCP. Data Center TCP algorithm has newly been anticipated as a TCP option for data centers which address these limitations. It is worth noting that traditional TCP protocol.

Future WLAN devices will combine both IEEE 802.11ad and 802.11ac interfaces. The former provides multi-Gbps rates but is susceptible to blockage, whereas the latter is slower but offers reliable connectivity. A fundamental challenge is thus how to combine those complementary technologies, to make the most of the advantages they offer. In this work, we leverage Multipath TCP (MPTCP) to use both interfaces simultaneously in order to achieve a higher overall throughput as well as seamlessly switch to a single interface when the other one fails. We find that standard MPTCP often performs sub-optimally and can yield a throughput much lower than that of single path TCP over the faster of the two interfaces. We analyze the cause of these performance issues in detail and then design <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">MuSher</i> , an agile MPTCP scheduler that allows MPTCP to fully utilize the channel resources available to both interfaces. Our evaluation in realistic scenarios shows that <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">MuSher</i> can provide a throughput improvement of 50%/130% under WLAN/Internet settings respectively, compared to the default MPTCP scheduler. It further speeds up the recovery of a traffic stream after disruption by a factor of 8x/75x.

Future WLAN devices will combine both IEEE 802.11ad and 802.11ac interfaces. The former provides multi-Gbps rates but is susceptible to blockage, whereas the latter is slower but offers reliable connectivity. A fundamental challenge is thus how to combine those complementary technologies, to make the most of the advantages they offer. In this work, we explore leveraging Multipath TCP (MPTCP) to use both interfaces simultaneously in order to achieve a higher overall throughput as well as seamlessly switching to a single interface when the other one fails. We find that standard MPTCP often performs sub-optimally and may even yield a throughput much lower than that of single path TCP over the faster of the two interfaces. We analyze the cause of these performance issues in detail and then design MuSher, an agile MPTCP scheduler that allows MPTCP to fully utilize the channel resources available to both interfaces. Our evaluation in realistic scenarios shows that MuSher provides a throughput improvement of up to 1.5x/2.3x and speeds up the recovery of a traffic stream, after disruption, by a factor of up to 8x/75x, under WLAN/Internet settings respectively, compared to the default MPTCP scheduler.

Web pages and web-based services are becoming more and more complex. The average page size for the Alexa top 1000 websites in 2016 has reached 2.1 MB and fetching a page requires requests for 128 different objects. Although the bandwidth has been increasing exponentially in the last few years, the web experience is not improving at the same pace because of latency issues in HTTP/1. The HTTP/2 protocol aims to solve these issues by allowing clients and servers to multiplex HTTP requests and responses on a single TCP connection. If HTTP/2 is widely adopted, it can have enormous benefits not only for the user experience, but also for the servers and the network. Since clients do not have to open multiple parallel connections to avoid the problem of head-of-line blocking in HTTP/1.1, the number of concurrent TCP sessions can be significantly reduced. However, although multiplexing is one of the main features of HTTP/2, nothing actually prevents a client from opening multiple HTTP/2 connections to a server. In this paper we investigate the behavior of HTTP/2 traffic in the wild. We perform experiments to examine if web browsers use a single connection per domain over HTTP/2 in practice. Contrary to popular belief, our experiments on the traffic of a large university campus network and a residential network show that a significant number of HTTP/2 accesses are performed using parallel connections to a single domain on a server. We present two possible hypotheses for this behavior and discuss its implications for the future of the web.

A new version of hypertext transfer protocol HTTP/2 was proposed. The protocol is expected to solve the Head of Line (HOL) blocking problem with a single TCP connection. In this paper, we evaluate the performance of HTTP/2 communication with a variety of conditions. We then show that HTTP/2 with a single connection can provide performances similar to those of HTTP/1.1 with multiple connections in many cases. In addition, we show also that HTTP/2 cannot present comparable performance in a network with high latency and high packet loss ratio.