Single TCP Connection Research Articles

Surveillance Camera Using Wi-Fi Connection

This research paper aims to design an energy-efficient surveillance camera utilizing the ESP32-CAM module, incorporating Wi-Fi connectivity, and using 3D printed custom case made from ABS plastic. The central goal is to determine the most effective video streaming protocol for transmitting real-time data to a web-based interface that manages the camera. The camera prototype is developed through a technical feasibility study and prototype construction methods, with a primary focus on assessing power consumption across various protocols including HTTP, RTP, RTSP, and WebSocket. The findings indicate that WebSocket emerges as one of the most optimal and power-efficient protocols for streaming video from the ESP32-CAM web server to a client device. This superiority arises from WebSocket's browser-based approach, enabling full-duplex communication through a single TCP connection, thereby facilitating real-time interaction between the client and server.

D-OLIA: A Hybrid MPTCP Congestion Control Algorithm with Network Delay Estimation.

With the recent evolution of mobile technology, modern devices equipped with multiple communication interfaces have become popular. The multipath transmission control protocol (MPTCP) has evolved to facilitate multiple communication interfaces through a single TCP connection for faster Internet access. MPTCP congestion control algorithms (MPTCP-CCAs) control data flow by fulfilling three design goals, i.e., ensuring improvement over single-path flows, ensuring fairness, and balancing congestion. Current MPTCP-CCAs cannot fulfill these design goals. For example, the opportunistic-linked increase algorithm (OLIA), a well-known MPTCP-CCA in load balancing, often results in low throughput because it cannot properly utilize the underlying network. In addition, the current Internet has a rapidly changing characteristic due to a large amount of short-lived traffic, making it difficult for MPTCP-CCAs to cope. An awareness of prevailing network delay conditions might help MPTCP-CCAs to utilize the network capacity fully. Therefore, we propose dynamic OLIA (D-OLIA), a hybrid MPTCP-CCA that enhances the performance of OLIA by integrating an awareness of the current network delay condition for deciding the congestion window (CWND) decrease factor. We estimate the current network delay condition, i.e., less-congested or congested, by observing the changes in the round-trip-time (RTT). Based on the estimated network delay condition, we decide the CWND decrease factor in real-time for reducing the CWND during packet loss events. We implemented D-OLIA in the Linux kernel and experimented using the Mininet emulator. The emulation results demonstrate that D-OLIA successfully estimates current network delay conditions and results in approximately a 20% increased throughput compared to the original OLIA. Compared to certain MPTCP-CCAs, it also yields a highly improved performance in terms of throughput, RTT, packet retransmissions, and fairness among the MPTCP sub-flows.

User-Controlled Subflow Selection in MPTCP: A Case Study

It is common to find multiple network interfaces connected to different Internet Service Providers (ISPs) in devices such as smartphones. Multipath TCP (MPTCP) enables TCP connections to use all these network interfaces in a single TCP connection in an application transparent manner. MPTCP schedules traffic of one TCP connection over subflows created over these network interfaces. It is evident that this requires some scheduling policy. There have been some attempts to allow applications to decide on the scheduling policy. However, this violates the application transparency of MPTCP, and applications do not have all the information required to decide on such a policy. In addition, this allows the applications to monopolize the network connection thus posing a security threat as well. We argue that only the owner of the device (the user) has the right to make that policy decision and only the user can make an informed decision on the scheduling policy. For example, the user has the information on the monetary cost of the connections through different interfaces. In this paper we present a mechanism that allows the user to provide hints to the TCP scheduler to alter its scheduling policy. While this is not a mechanism to implement generic scheduling policies, it demonstrates how a user can guide the scheduling policies. As a proof of the concept, we demonstrate how MPTCP scheduler can be influenced to select a less stable and lossy path over a stable path based on a user preference.

Multiplexed Asymmetric Attacks: Next-Generation DDoS on HTTP/2 Servers

Distributed Denial of Service (DDoS) attacks using the HTTP protocol have started gaining popularity in recent years. A recent trend in this direction has been the use of computationally expensive requests to launch attacks. These attacks, called Asymmetric Workload attacks can bring down servers using limited resources, and are extremely difficult to detect. The introduction of HTTP/2 has been welcomed by developers because it improves user experience and efficiency. This was made possible by the ability to transport HTTP requests and their associated inline resources simultaneously by using Multiplexing and Server Push. However multiplexing has made request traffic bursty and rendered DDoS detection mechanisms based on connection limiting obsolete. Contrary to its intention, multiplexing can also be misused to launch sophisticated DDoS attacks using multiple high workload requests in a single TCP connection. However, sufficient research has not been done in this area. Existing research demonstrates that the HTTP/2 protocol allows users to launch DDoS attacks easily, but does not focus on whether an HTTP/2 server can handle DDoS attacks more efficiently or not. Also, sufficient research has not been done on the possibility of Multiplexing and Server Push being misused. In this work, we analyse the performance of an HTTP/2 server compared to an HTTP/1.1 server under an Asymmetric DDoS attack for the same load. We propose a new DDoS attack vector called a Multiplexed Asymmetric DDoS attack, which uses multiplexing in a different way than intended. We show that such an attack can bring down a server with just a few attacking clients. We also show that a Multiplexed Asymmetric Attack on a server with Server Push enabled can trigger an egress network layer flood in addition to an application layer attack.

Achieving Robust Mobile Web Content Delivery Performance Based on Multiple Coordinated QUIC Connections

In order to minimize the downloading time of short-lived applications like Web browsing, Web application, and short video clips, the recently standardized HTTP/2 adopts stream multiplexing on one single TCP connection. However, aggregating all content objects within one single connection suffers from the head-of-line blocking issue. Quick UDP Internet connection (QUIC), by eliminating such an issue on the basis of UDP, is expected to further reduce the content downloading time. However, in mobile network environments, the single connection strategy still leads to a degraded and high-variant completion time due to the unexpected hindrance of congestion window growth caused by the common but uncertain fluctuations in round trip time and also random loss event at the air interface. To retain resilient congestion window against such network fluctuations, we propose an intelligent connection management scheme based on QUIC which not only employs adaptively multiple connections but also conducts a tailored state and congestion window synchronization between these parallel connections upon the detection of network fluctuation events. According to the performance evaluation results obtained from an LTE-A/Wi-Fi testing network, the proposed multiple QUIC scheme can effectively overcome the limitations of different congestion control algorithms (e.g., the loss-based new reno/CUBIC and the rate-based BBR), achieving substantial performance improvement in both median (up to 59.1%) and 95th completion time (up to 72.3%). The significance of this piece of work is to achieve highly robust short-lived content downloading performance against various uncertainties of network conditions as well as with different congestion control schemes.

An active de-anonymizing attack against tor web traffic

Tor is pervasively used to conceal target websites that users are visiting. A de-anonymization technique against Tor, referred to as website fingerprinting attack, aims to infer the websites accessed by Tor clients by passively analyzing the patterns of encrypted traffic at the Tor client side. However, HTTP pipeline and Tor circuit multiplexing techniques can affect the accuracy of the attack by mixing the traffic that carries web objects in a single TCP connection. In this paper, we propose a novel active website fingerprinting attack by identifying and delaying the HTTP requests at the first hop Tor node. Then, we can separate the traffic that carries distinct web objects to derive a more distinguishable traffic pattern. To fulfill this goal, two algorithms based on statistical analysis and objective function optimization are proposed to construct a general packet delay scheme. We evaluate our active attack against Tor in empirical experiments and obtain the highest accuracy of 98.64%, compared with 85.95% of passive attack. We also perform experiments in the open-world scenario. When the parameter k of k-NN classifier is set to 5, then we can obtain a true positive rate of 90.96% with a false positive rate of 3.9%.

Analysis of multiple flows using different high speed TCP protocols on a general network

We develop analytical tools for performance analysis of multiple TCP flows (which could be using TCP CUBIC, TCP Compound, TCP New Reno) passing through a multi-hop network. We first compute average window size for a single TCP connection (using CUBIC or Compound TCP) under random losses. We then consider two techniques to compute steady state throughput for different TCP flows in a multi-hop network. In the first technique, we approximate the queues as M/G/1 queues. In the second technique, we use an optimization program whose solution approximates the steady state throughput of the different flows. Our results match well with ns2 simulations.

Towards a SPDY’ier Mobile Web?

Despite its widespread adoption and popularity, the Hypertext Transfer Protocol (HTTP) suffers from fundamental performance limitations. SPDY, a recently proposed alternative to HTTP, tries to address many of the limitations of HTTP (e.g., multiple connections, setup latency). In this paper, we perform a detailed measurement study to understand the benefits of using SPDY over cellular networks. Through careful measurements conducted over 4 months, we provide a detailed analysis of the performance of HTTP and SPDY, how they interact with the various layers, and their implications on Web design. Our results show that unlike in wired and 802.11 networks, SPDY does not clearly outperform HTTP over cellular networks. We identify negative interactions between the protocols used for Web access (HTTP/SPDY over TCP) and cellular radio resource management as the underlying cause. Overall performance suffers when devices go through a cellular radio state promotion after an idle period, and the consequent increase in latency. This impacts SPDY more because of the use of a single TCP connection. We conclude that a viable solution has to account for these unique cross-layer dependencies to achieve improved Web performance over cellular networks.

Server Load – Balancing using Resources of Clustering Technique

Load Balancing is one of the most important issues for clustered servers. Load Balancing is done on the basis of server traffic. The proposed algorithm uses user-session history as the other constraint which is very useful for resource management over the server and easy access for the client. Collection of the data of a particular client from the last user-session, groups the applications that are likely to be opened in a specific time frame. This will provide easy access to the client and will reduce resource wastage on the server by using cluster technology. The primary clusters will be based on the bandwidth of the client’s internet bandwidth, which will map to different servers. Whereas secondary clusters will be based on the similarity of application-usage in the past user-session. This approach can reduce the unnecessary searching time. Cluster management will provide better approachability towards the server also the bandwidth based load balancing will lead to the minimum bandwidth wastage. Keywords Clustering, Load Balancing, Scalability, Client-Server, Resource Management, Cluster Creation, Cluster allocation, Cluster Reallocation, Cluster Management and Cloud Computing 1. INTRODUCTION The inspiration behind any Client-Server technology, arguably is its capacity to handle n no. of transactions in a given span of Time. Today, in the much credited dynamic environment “Scalability” is the concern for modern day Computer Scientist and Algorithm Pundits. You have only few ways left to deal with performance issues. 1. Either you are forced to upgrade hardware resources or 2. A load balancing [1] algorithm to find smart costefficient ways to fetch the user their desired resources without compromising Quality of Service. Coming directly to Load balancing on the Server, various methods have been used in past to balance the same, yet some haven’t got desired outcome. Clustering technique had been used in the near past for better fetch and efficient server loadmanagement Clustering Technique [2] is exploratory technique used in many areas to analyze large data sets. Given a proper notion of similarity, they find groups of similar variables/objects by partitioning the data set in “similar subsets”. Typically, several metrics over which a distance measure can be defined are associated with points (named samples) in the data set. There usually are various Clustering techniques available. Most used amongst them are I) Hierarchical and II) Partitioning clustering techniques. User Session Deduction is one of most important criteria for Load-Balancing, given the technique to be used is Server-Clusters. User-Session Identification has been non-trivial task to be performed on-the-go real time. Applications such as telnet or ssh typically generate a single TCP connection per single user-session, whereas application layer protocols such as HTTP, IMAP/SMTP and X11 usually generate multiple TCP connections per user-session. User-session characterization genuinely allows researchers to build realistic scenarios when assessing the performance of a complex network via simulation. Earlier Problems included I) Missed user Sessions, as threshold value had to be statically stated to tell the server that it is running over capacity. Vague, as it may sound, any usersession could be missed once there is bottleneck of connections asking permission for a connection establishment. II) Possibility of a huge data lose once there is a system failure since no backup image available, only to add to the chaos, a main server did not have any backup server available to route traffic towards that server. III) Every returning User had to start-over every time he/she terminates the session, it led to huge delay in page requested and page Fetched. As every user was forced to visit the prespecified pages and not the user-desired page. Our Approach will ensure a proper user session deduction takes place. The Algorithms will make sure to time stamp every usersession so that in case of any missing sessions the timestamp will auto-correct it’s reading. Apart from these a smart Artificial Intelligence Engine will predict user behavior with respect to their usage at different point of times. This will help user to directly visit his/ her required page rather than logging in again and getting diverted once again to Homepage. Also a smart cluster allocation Engine and cluster management algorithm will work hand in hand and deliver realtime cluster allocation to users without any hassles whatsoever. Even Cluster Allocation depends upon various parameters viz. Bandwidth, Predicted userbehavior. International Journal of Computer Applications (0975 – 8887) Volume 125 – No.5, September 2015 26 Fig 1: Architecture Diagram

Exploring TCP Parallelisation for performance improvement in heterogeneous networks

TCP Parallelisation uses a set of parallel (modified or standard) TCP connections to transfer data for an application process. With standard TCP connections, TCP Parallelisation has been used to effectively utilise bandwidth for data intensive applications over high bandwidth-delay product (BDP) networks. On the other hand, it has been argued that a single TCP connection with proper modification can emulate and capture the robustness of TCP Parallelisation and thus can well replace TCP Parallelisation. A typical example is HSTCP, which can emulate the behaviour of a set of multiple standard TCP connections. However, through the analysis and the proposed use of TCP Parallelisation in this paper, we found that TCP Parallelisation has its unique merits, which cannot be emulated by a single-connection based approach. As a result, the single-connection based approach (such as HSTCP) may not be able to achieve the same effects as TCP Parallelisation, especially in heterogeneous networks and highly dynamic environments (e.g., high BDP networks combined with wireless access links). In this paper, we demonstrate some of these unique merits of TCP Parallelisation (namely, localisation of disturbances such as Fast Recovery, loss synchronisation between parallel connections and self- healing) over single-connection based approach in the heterogeneous environment.

Cross‐layer protocols for satellite communication networks: part I

Cross‐layer protocols for satellite communication networks: part I

Stability and Analysis of TCP Connections with RED Control and Exogenous Traffic

In this paper we study the stability and performance of a system involving several TCP connections passing through a tandem of RED controlled queues each of which has an incoming exogenous stream. The exogenous stream, representing the superposition of all incoming UDP connections into a queue, has been modeled as an MMPP stream. We consider both the TCP Tahoe and the TCP Reno versions. We start with the analysis of a single TCP connection sharing a RED controlled queue with an exogenous stream. The effect of the exogenous stream (which is almost always present in large networks) is to cause the system to converge to a stationary distribution from any initial conditions. This stability result holds good for any work conserving discipline. We also obtain the performance indices of the system; specifically the goodputs and the mean sojourn times of the various connections. The complexity involved in computation of performance indices for the system is reduced by approximating the evolution of the average queue length process of the RED queue by a deterministic ODE. Then, by using a decomposition approach of two time scales, we reduce the study of the system to that of a simplified one for which the performance measures can be obtained under stationarity. Finally, we extend the above results to the case when multiple TCP connections share a RED controlled queue with an exogenous stream and to the case when a TCP connection passes through several RED controlled tandem queues each of which has an incoming exogenous stream. We also consider an example of multiple TCPs passing through a tandem of queues. A number of simulation results have been provided which support the analysis.

IP-in-IP tunneling to enable the simultaneous use of multiple IP interfaces for network level connection striping

With ubiquitous computing and network access now a reality, multiple network conduits are become widely available to mobile as well as static hosts: for instance wired connections, 802.11 style wireless LANs, Bluetooth, and cellular phone modems. Selection of the preferred mode of data transfer is a dynamic optimization problem which depends on the type of application, its bandwidth/latency/jitter requirements, current network conditions (such as congestion or traffic patterns), cost, power consumption, battery life, and so on. Furthermore, since wireless bandwidth is likely to remain a scarce resource, we foresee scenarios wherein mobile hosts will require simultaneous data transfer across multiple IP interfaces to obtain higher overall bandwidth. We present a brief overview of existing work which enables the simultaneous use of multiple network interfaces and identify the applicability as well as strengths and weaknesses of these related approaches. We then propose a new mechanism to aggregate the bandwidth of multiple IP paths by splitting a data flow across multiple network interfaces at the IP level. We have analyzed the performance characteristics of our aggregation scheme and demonstrate significant gains when the network paths being aggregated have similar bandwidth and latency characteristics. In addition, our method is transparent to transport (TCP/UDP) and higher layers, and allows the use of multiple network interfaces to enhance reliability. Our analysis identifies the conditions under which the proposed scheme, or any other scheme that stripes a single TCP connection across multiple IP paths, can be used to increase throughput.

Energy efficiency of TCP in a local wireless environment

The focus of this paper is to analyze the energy consumption performance of various versions of TCP, namely, Tahoe, Reno and NewReno, for bulk data transfer in an environment where channel errors are correlated. We investigate the performance of a single wireless TCP connection by modeling the correlated packet loss/error process (e.g., as induced by a multipath fading channel) as a first-order Markov chain. Based on a unified analytical approach, we compute the throughput and energy performance of various versions of TCP. The main findings of this study are the (1) error correlations significantly affect the energy performance of TCP (consistent with analogous conclusions for throughput), and in particular they result in considerably better performance for Tahoe and NewReno than iid errors, and (2) the congestion control mechanism implemented by TCP does a good job at saving energy as well, by backing off and idiling during error bursts. An interesting conclusion is that, unlike throughput, the energy efficiency metric may be very sensitive to the TCP version used and to the choice of the protocol parameters, so that large gains appear possible.

Throughput analysis of TCP on channels with memory

The focus of this paper is to analyze the relative sensitivity of the bulk throughput performance of different versions of TCP, viz., OldTahoe, Tahoe, Reno, and New Reno, to channel errors that are correlated. We investigate the performance of a single wireless TCP connection in a local environment by modeling the correlated packet loss/error process (e.g., as induced by a multipath fading channel) as a first-order Markov chain. A major contribution of the paper is a unified analytical approach which allows the evaluation of the throughput performance of various versions of TCP. The main findings of this study are that 1) error correlations significantly affect the performance of TCP, and in particular may result in considerably better performance for Tahoe and NewReno; and 2) over slowly fading channels which are characterized by significant channel memory, Tahoe performs as well as NewReno. This leads us to conclude that a clever design of the lower layers that preserve error correlations, naturally present on wireless links because of the fading behavior, could be an attractive alternative to the development or the use of more complex versions of TCP.