Multipath TCP

Multipath transmission control protocol (TCP), or MPTCP, is a widely-researched mechanism that allows a single application-level connection to be split to more than 1 TCP stream and, consequently , more than 1 network interface, as opposed to the traditional TCP/IP model. Being a transport layer protocol, MPTCP can easily interact between the application using it and the network supporting it. However, MPTCP does not have control of its own route. Default IP routing behavior generally takes all traffic through the shortest or best metric path. However, this behavior may actually cause paths to collide with each other, creating contention for bandwidth in a number of edges. This can result in a bottleneck that limits the throughput of the network. Therefore, a multipath routing mechanism is necessary to ensure smooth operation of MPTCP. We created smoc, a simple multipath OpenFlow controller, that uses only topology information of the network to avoid collision where possible. Evaluation of smoc in a virtual local-area and a physical wide-area software-defined networks showed favorable results as smoc provided better performance than simple or spanning tree-routing mechanisms.

— We develop a comprehensive analytical model for multiple long-lived multipath Transmission Control Protocol (TCP) connections downloading content from a remote server in the Internet using parallel paths with Wi-Fi and cellular last-miles. This is the first analytical model developed in the literature that captures the coupling between the paths through heterogeneous wireless networks where the coupling arises due to the multipath TCP coupled congestion control protocol. The model also takes into account the impact of the shared nature of the wireless medium and the finite access point (AP) buffer in the Wi-Fi last-mile. The accuracy of the proposed model is demonstrated via extensive ns-2 simulations. Furthermore, we discover a new type of throughput unfairness among the competing regular and multipath TCP connections going through the same AP with a droptail buffer; the regular TCP connections essentially steal almost all the Wi-Fi bandwidth away from the multipath TCP connections. To tackle this problem, we present two simple solutions utilizing our analytical model and achieve fairness.

Wireless communication platforms of unmanned aerial vehicles (UAVs), commonly known as drones, usually operate in dynamic conditions with highly fluctuating capacities and erratic wireless access to the network resources. Effective design for adequate, robust and consistent communications from the drones to the control center (aka server) is thus necessary to facilitate the implementation of the UAV system. Multipath TCP has the potential to exploit heterogeneous wireless paths and achieve robust bandwidth by controlling the dynamics of the convoy of drones. In this paper, we make use of fluid approach for proposing a generic system architecture towards a control mechanism for coordinating the convoy of drones. Moreover, we model multipath TCP and study their applications for the control scenario of a convoy of drones with three different communication interfaces, representing the head, tail and the middle of the convoy. The access is through a Satellite and several WiFi access points (APs) communicating to the server with time-variant wireless channel, subject to the dynamic mobility and distance of APs from the convoy's head and tail. The traffic on different paths governed by the flow control based on the movement and position of the convoy enable us to investigate the performance and convergence of communication system dynamics. In particular, Lyapunov theory is adopted to derive the stability conditions of the dynamics over the mobility of the convoy.

Recent advancements in Internet congestion control have introduced a multipath TCP (MPTCP) that aims to simultaneously utilize multiple available paths in the network. In this paper, we develop an integrated fluid and packet-level analytical model to study the coexistence of regular and MPTCP users sharing a common WiFi access point (AP). We observe a throughput unfairness of MPTCP with regular TCP in the last-mile WiFi networks. In order to fix the fairness issue, we develop a real-time Adaptive Loss Management (ALM) algorithm that continuously monitors the deviation in AP buffer occupancy and adapts its packet admission probability based on a closed form expression derived from our analytical model. We provide a proof as well as show via numerical and simulation results that the proposed ALM algorithm is TCP-friendly by design, and provably stable.

TCP is one of the main protocols that govern the Internet traffic nowadays. However, it suffers significant performance degradation over wireless links. Since wireless networks are leading the communication technologies recently, it is imperative to introduce effective solutions for the TCP congestion control mechanisms over such networks. In this research four End-to-End TCP implementations are discussed, they are TCP Westwood, Hybla, Highspeed, and NewReno. The performance of these variants is compared using LTE emulated environment in terms of throughput, delay, and fairness. Ns-3 simulator is used to simulate the LTE networks environment. The simulation results showed that TCP Highspeed achieves the best throughput results. Although TCP Westwood recorded the lowest latency values comparing to others, it behaved unfairly among different traffic flows. Moreover, TCP Hybla demonstrated the best fairness behaviour among other TCP variants.

With the proliferation of mobile and wireless computing devices, the demand for continuous network connectivity exits for various wired-and-wireless integrated networks. Since Transmission Control Protocol (TCP) is the standard network protocol for communication on the Interne, any wireless network with Internet service need to be compatible with TCP. TCP is tuned to perform well in traditional wired networks, where packet losses occur mostly because of congestion. However cellular wireless network suffers from significant losses due to high bit errors and mobile handoff. TCP responds to all losses by invoking congestion control and avoidance algorithms, resulting in degraded end-to-end performance. This paper presents an improved Explicit Loss Notification algorithm to distinguish between packet loss due to congestion and packet loss due to wireless errors and handoffs. Simulation results show that the proposed protocol significantly improves the performance of TCP over cellular wireless network in terms of throughput and congestion window dynamics.

—A complete understanding of the dynamics of Multipath TCP (MPTCP) over Cellular and WiFi networks is still lacking. This is a highly challenging issue, as a consequence of the complex interdependencies between the losses, packet reordering due to heterogeneous wireless channel features, errors and link layer retransmissions, as well as their (joint) influence on MPTCP's control mechanism. In this paper we develop a comprehensive approach that is capable of assessing the performance of long-lived MPTCP flows with joint WiFi and Cellular network access, taking into account the diverse characteristics of both types of networks. Relying on a parallel queueing model, we develop a framework that features the controllable network parameters, such as the retransmission limit and the buffer sizes, so as to capture their impact on the TCP-level performance. We include a variety of numerical and simulation results highlighting various non-trivial findings and insights for adaptive MPTCP design. In particular, we design a novel MPTCP algorithm to exploit the route heterogeneity, and demonstrate that the proposed algorithm is capable of learning the network's characteristics. It also identifies the improved MPTCP window increment parameters for any given set of channel errors, retransmission limits, and buffer sizes.

http://airccse.org/journal/jwmn/0510ijwmn08.pdf Channel estimation for LTE Uplink system by Perceptron neural network http://airccse.org/journal/jwmn/0203ijwmn11.pdf LACBER: New Location Aided Routing Protocol For GPS Scarce Manet http://airccse.org/journal/nsa/0809smn02.pdf Performance Analysis of LS and LMMSE Channel Estimation Techniques for LTE Downlink Systems http://airccse.org/journal/jwmn/1011wmn11.pdf Performance Analysis of On-Demand Routing Protocols for Vehicular Ad-Hoc Networks http://airccse.org/journal/jwmn/0811wmn07.pdf An Intelligent Network Selection Strategy Based on MADM Methods in Heterogeneous Networks http://airccse.org/journal/jwmn/0212wmn06.pdf Zigbee Based Voice Controlled Wireless Smart Home System http://airccse.org/journal/jwmn/6114ijwmn04.pdf Vertical Handoff In Wlan-Wimax-Lte Heterogeneous Networks Through Gateway Relocation http://airccse.org/journal/jwmn/0812wmn15.pdf Mobile Agent Based Congestion Control Using AODV Routing Protocol Technique for Mobile Ad-Hoc Network http://airccse.org/journal/jwmn/0412wmn20.pdf Optimization of Energy Consumption for OLSR Routing Protocol in MANET http://airccse.org/journal/jwmn/0212wmn19.pdf

With the increasing demand of mobile data traffic, cellular networks are evolving towards heterogeneous systems involving cells of different sizes (e.g., pico, micro, and macro cells). The presence of small cells is causing new interference issues that require the introduction of frequency reuse techniques suitable to manage both co-tier and cross-tier interference. In this paper, we propose a novel Soft Frequency Reuse (SFR) scheme for LTE-A, based on three frequency segments (named Three-Band Improved SFR, 3B-ISFR) where the Frequency Reuse Pattern (FRP) allocation scheme for micro cells is centralized at the level of each macro cell. This scheme is based on the exchange of measurements made by the micro cells with their macro cell (cognitive-assisted approach) and includes an intra-cell offloading algorithm to balance the load between cell-center and cell-edge of each micro/macro cell. The goodness of 3B-ISFR has been proved by means of performance comparisons with other schemes in the literature in terms of outage probability and average cell capacity.

Mobile Ad-hoc Networks (MANETs) are self configuring, decentralized and dynamic nature wireless networks which have no infrastructure. These offer a number of advantages, however the demand of high
traffic flows in MANETs increases rapidly. For these demands, limited bandwidth of wireless network is the important parameter that restrains the development of real time multimedia applications. In this work, we propose a solution to utilize available bandwidth of the channel for on demand multiple disjoint paths. The approximate bandwidth of a node is used to find the available bandwidth of the path. The source chooses the primary route for data forwarding on the basis of path bandwidth. The simulation results show that the
proposed solution reduces the frequency of broadcast and performs well in improving the end to end throughput, packet delivery ratio, and the end to end delay.

Multipath routing in WSN has been a long wish in security scenario where nodes on next-hop may be
targeted to compromise. Many proposals of Multipath routing has been proposed in ADHOC Networks but
under constrained from keying environment most seems ignorant. In WSN where crucial data is reported by
nodes in deployment area to their securely located Sink, route security has to be guaranteed. Under
dynamic load and selective attacks, availability of multiple secure paths is a boon and increases the
attacker efforts by many folds. We propose to build a subset of neighbors as our front towards destination
node. We also identified forwarders for query by base station. The front is optimally calculated to maintain
the security credential and avail multiple paths. According to our knowledge ours is a novel secure
multipath routing protocol for WSN. We established effectiveness of our proposal with mathematical
analysis.

Multipath TCP (MPTCP) is an extension to TCP which aggregates multiple parallel connections over available network interfaces. MPTCP bases its scheduling decisions on the individual RTT values observed at the subflows, but does not attempt to perform any kind of joint optimization over the subflows. Using the MPTCP scheduler as an example, in this paper we demonstrate that exploiting cross-layer information and optimizing scheduling decisions jointly over the multiple flows, can lead to significant performance gains. While our results only represent a single data point, they illustrate the need to look at MPTCP from a more holistic point of view and not treat the connections separately, as is currently being done. We call for new approaches and research into how multiple parallel connections offered by MPTCP should be used in an efficient and fair manner.

Heikki HÄMMÄINENa, 1, Alan FORDb, Alexandros KOSTOPOULOSc, Bernd HEINRICHd, Tapio LEVÄa, Ralf WIDERAd and Costas COURCOUBETISc a Helsinki University of Technology, Finland heikki. hammainen@ tkk. fi b Roke Manor Research, United Kingdom c Athens University of Economics and Business, Department of Informatics, Greece d T–Systems Enterprise Services GmbH, Germany Keywords. Future Internet, multipath TCP, resource pooling, business models, use cases, incentives

Wireless communication platforms of unmanned air vehicles (UAVs), commonly known as drones, usually operate in dynamic conditions with highly fluctuating capacities and erratic wireless access to the network resources. Effective design for adequate, robust and consistent communications from the drones to the control center (aka server) is thus necessary to facilitate the implementation of the UAV system that is still lacking in literature. Multipath TCP has the potential to exploit heterogeneous wireless paths and achieve robust bandwidth by controlling the dynamics of the convoy of drones. In this paper, we make use of fluid approach for proposing a generic system architecture towards a control mechanism for coordinating the convoy of drones. Moreover, we model multipath TCP and study their applications for the scenario of a convoy of drones with three different communication interfaces, representing the head, tail and the middle of the convoy. The access is through a Satellite and WiFi access points (APs) communicating to the server with time-variant wireless channel, subject to the dynamic mobility and distance of APs from the convoy head and tail. The traffic on different paths governed by the flow control based on the movement and position of the convoy enable us to investigate the the performance and convergence of communication system dynamics. In particular, Lyapunov theory is adopted to derive the stability conditions of the dynamics over the mobility of the convoy.

— Operating synthetic aperture sonar (SAS) in shallow water environment can be challenging owing to multiply reflected signals interfering with the direct signal. We use the space-alternating generalized expectation maximization (SAGE) algorithm to estimate the multipath signal parameters. Specifically, we estimate the relative time delay of surface reflected signal to direct signal and the directions of arrivals of each signal. Using these estimates, we extract only the direct arrival signal which is used for SAS signal processing. Compared to using an adaptive beam-former, SAS system using the proposed algorithm shows better performance in terms of reducing multipath interference effects. Keywords—Multipath, parameter estimation, SAGE algorithm, synthetic aperture sonar.

Internet was originally designed for one-to-one application process communication. With the tremendous growth and popularity of Internet, a number of new Internet applications have been introduced. Many applications exist today including live media streaming and video on demand which breach the one to one communication paradigm. With the increased use of multicast applications there is greater need for making communication reliable and bandwidth efficient. A large number of applications running on the Internet today use Transmission Control Protocol (TCP). Multipath TCP (MPTCP) allows multiple communication paths to exist between communicating devices. In this paper the performance of MPTCP is evaluated in wireless multicast scenarios for the first time. We run simulations to measure parameters of throughput, latency, and jitter. We also show the effects of varying multicast group size. The results show that MPTCP provides increased bandwidth with more reliable communication compare...