Transmission Control Protocol Connections Research Articles

Developed the EX-RED Algorithm to Find Best Parameters Based on Load Connection Factor

The performance of the Internet is significantly impacted by network congestion. Because of the internet's current rapid growth, congestion could increase and cause more packets to be dropped. The Transmission Control Protocol (TCP) connection is used as the reliable transmission of packets which has a Drop Tail (DT) mechanism since congestion DT signals occur only when the queue has become full. The Random Early Detection algorithm mechanism can be developed as congestion control which eliminates the drawback of a tail drop queue full. The Red algorithm also has problems dealing with different numbers of connections due to fix parameter tuning. In this study, the EXhaustive search used with the RED algorithm to develop the EX-RED algorithm. Based on network performance metrics such as packet drop, delay, and throughput, the developed algorithm adjusts the default RED parameter to find the best of them. When the number of TCP connections changes, the exhaustive search used systematically enumerates all possible states of the parameter. The simulation results showed that the EXRED improved performance of the network as compared with the other five algorithms (GRED, RED, ARED, NLRED, and NLGRED) by decreasing delay and dropped packets and increasing packet throughput. Index Terms— AQM, Congestion Control, Exhaustive search, RED.

Cross-layer modeling and analysis of TCP communications over turbulent FSO links

This paper addresses the accurate characterization of the performance of transmission control protocol (TCP) for end-to-end transport services over free-space optical (FSO) links. Unlike previous works on this topic, we introduce a second-order Markovian assumption for the variation of the TCP congestion window to capture the memory from turbulence channels and further propose a Markov chain model that maps two consecutive congestion windows along time into the state space to interpret TCP operations. The analytical expression of steady-state probability distribution vector of the proposed model in general cases where relay routers exist behind the TCP connection is derived, based on which the throughput efficiency of TCP is formulated. The high accuracy of the proposed model is verified by Monte-Carlo simulations and experiments. We further analyze the impact of different link/channel parameters on the TCP performance, and discuss briefly the effectiveness of bundle protocol-based schemes for improving the performance of FSO networks from a transport layer perspective.

DoSDefender: A Kernel-Mode TCP DoS Prevention in Software-Defined Networking.

The limited computation resource of the centralized controller and communication bandwidth between the control and data planes become the bottleneck in forwarding the packets in Software-Defined Networking (SDN). Denial of Service (DoS) attacks based on Transmission Control Protocol (TCP) can exhaust the resources of the control plane and overload the infrastructure of SDN networks. To mitigate TCP DoS attacks, DoSDefender is proposed as an efficient kernel-mode TCP DoS prevention framework in the data plane for SDN. It can prevent TCP DoS attacks from entering SDN by verifying the validity of the attempts to establish a TCP connection from the source, migrating the connection, and relaying the packets between the source and the destination in kernel space. DoSDefender conforms to the de facto standard SDN protocol, the OpenFlow policy, which requires no additional devices and no modifications in the control plane. Experimental results show that DoSDefender can effectively prevent TCP DoS attacks in low computing consumption while maintaining low connection delay and high packet forwarding throughput.

Highly Concurrent TCP Session Connection Management System on FPGA Chip

Transmission Control Protocol (TCP) is a connection-oriented data transmission protocol, and it is also the main communication protocol used for end-to-end data transmission in the current Internet. At present, the mainstream TCP protocol processing service is implemented by software running on the Central Processing Unit (CPU). However, with the rapid growth of transmission bandwidth and the number of connections, the software-based processing method is not ideal in terms of delay and throughput, and also affects the processing performance of the CPU in other applications such as virtualization services. Moreover, other hardware solutions can only support a limited number of TCP session connections. In order to improve the processing efficiency of the TCP protocol and achieve highly concurrent network services, this paper proposes a TCP offload engine (TOE) prototype system based on field programmable gate array (FPGA) chips. It not only provides hardware-based data path processing, but also realizes hardware management of large-scale TCP session connection status through a multi-level cache management mechanism. Studies have shown that this solution can support 100 Gbps high-performance throughput characteristics, and allow concurrent processing of hundreds to 250,000 TCP connection state hardware maintenance on a single network node, improving the overall performance of the network system.

Leveraging eBPF to Make TCP Path-Aware

The Transmission Control Protocol (TCP) is one of the key Internet protocols. It is used by a broad range of applications. TCP was designed when there was typically a single path between a client and a server. Today’s networks provide higher path diversity, yet TCP still only uses the single path selected by the network layer. This limits the ability of TCP to react to events such as interdomain failures or highly congested peering links. We propose the TCP Path Changer (TPC), a set of eBPF programs that are incorporated into the Linux TCP/IP stack to make it more agile. To illustrate the benefits of our approach, we first demonstrate that TPC can quickly reroute an ongoing TCP connection around a failure. We then show that TPC can also monitor the round-trip-time of active TCP connections and automatically reroute them if it becomes too high. Our evaluation of TPC in emulated networks evidences the significant performance benefits of a path-aware transport protocol.

On Cross-Layer Interactions for Congestion Control in the Internet

Two key mechanisms of the Internet are congestion control in the Transmission Control Protocol (TCP) and Active Queue Management (AQM) in routers. The former divides the bandwidth between flows and prevents the Internet from congestion collapse. Simultaneously, the latter informs hosts of the forthcoming congestion by preventive dropping of packets in network nodes. Although these two key mechanisms may severely interact with each other, they are often being researched independently, in parallel. This has led to the development of a few new congestion controls and AQM algorithms known for excellent performance under the assumption that the counterpart remains unaltered. It is unclear, however, how these new solutions in both areas interact with each other. The purpose of this paper is to fill this gap. Namely, in an extensive set of simulations, the impact of interactions between the state-of-the-art congestion control and AQM algorithms on the TCP connection performance is studied. As a result, recommendations for using some particular TCP-AQM pairs, which are observed to perform especially well, are formulated.

Data sequence signal manipulation in multipath TCP (MPTCP): The vulnerability, attack and its detection

Multipath Transmission Control Protocol (MPTCP) is an innovative next-generation transport protocol standardized by the Internet Engineering Task Force (IETF) to overcome the single path limitation of the Transmission Control Protocol (TCP). MPTCP augments TCP with a new set of signaling options for seamless transmission and reception of application data across multiple interlinked TCP connections called subflows. In this paper, we focus on a new security concern associated with the signal exchanging process of MPTCP. To the best of our knowledge, for the first time, this paper exposes that MPTCP signal exchange scheme is vulnerable to a sophisticated packet spoofing technique, which we name as Data Sequence Signal (DSS) manipulation. We implement the vulnerability, create attack scenarios in Linux Kernel and conduct experiments over emulated testbed to demonstrate the existence of the vulnerability and means of exploiting it for powerful attacks. Our results show that DSS manipulation can be tactically exploited, on top of TCP optimistic ACKing, to generate non-responsive traffic like Denial-of-Service (DoS) attack flood. Particularly, we demonstrate two new adverse scenarios, where a MPTCP sender is forced to: (a) transmit at a rate significantly higher than the bottleneck link bandwidth, and (b) induce high intensity and harmful packet bursts at line-rate called Maliciously-induced-Bursts (MiBs). We also show that the non-responsive traffic resulting from the attack can suppress genuine congestion controlled traffic to the extent of causing DoS attack. We capture and analyze the dynamics of important MPTCP parameters, like send buffer occupancy of meta and subflow sockets, congestion window and flightsize to highlight the attack impact. DSS manipulation originates from a fundamental protocol design limitation rather than from any implementation flaw. We also propose a novel technique called data sequence map skipping for detection and countermeasure against DSS manipulation based attacks.

Beyond socket options: Towards fully extensible Linux transport stacks

The Transmission Control Protocol (TCP) is one of the most important protocols in today’s Internet. It was designed to be extensible for various use cases. A client can propose to use an extension over a given TCP connection by sending a TCP option that identifies this extension. In practice, deploying a TCP extension is difficult as the maintainers of client stacks often wait until servers implement a given extension and server maintainers look at clients in the same manner. It often takes several years if not a decade to actually deploy a TCP option widely. Our goal is to support experimenting and deploying new TCP options in a quick, simple, and efficient way. This includes inserting new TCP options at the sender side and parsing them at the receiver side. The implementation and the interface should be simple, generic, and introduce as few changes to the kernel code as possible. In this paper, we focus on the Linux TCP stack since it is one of the most widely used TCP stacks, given its utilization on many servers and Android devices. For this purpose, we leverage the extended Berkeley Packet Filter (eBPF), which is a recently developed in-kernel infrastructure to enable high performance and safe programmability to the Linux kernel space.Multipath TCP (MPTCP) is a major TCP extension that enables more capabilities and has richer semantics than regular TCP. We implemented a similar methodology in the Linux MPTCP stack to support new use-cases through custom MPTCP options. Moreover, an eBPF-based framework for user-defined path managers is also proposed, given that subflow management is an important task in Multipath TCP.

An intelligent long-lived TCP based on real-time traffic regulation

Transmission control protocol (TCP) transaction is one of the chief protocols of Internet protocols. It is divided into two categories of data flow. (1) A small fraction of the TCP connections carried a small portion of the traffic called short-lived TCP. (2) A small fraction of the remaining TCP connections carried a large portion of the traffic called long-lived TCP. The main problem here is the transmission time; other data usually harm its flows, such as User Datagram Protocol (UDP) or short-lived TCP, and cause the unfairness in the network. In this paper, a novel framework is proposed to improve network throughput and to reduce the impact of long-lived TCP to other data flows. In this framework, each TCP connection passed by an edge network device and it will be observed for determining the long-lived TCP flows. Then, the detected long-lived TCP flow will be regulated based on predicting real-time traffic levels. Moreover, to highlight the benefits of the proposed framework, an analytical model is proposed to compare the proposed framework with the conventional TCP in terms of network performance. Experiments are conducted using the ns-2 benchmark in order to verify the results of the analytical model. The results showed that the analytical outcomes are promising and matched well with the outcomes of the ns-2 experiments. In the case of a high error rate, the proposed framework achieves higher reliability and reveals lower resource consumption.

Research on android infiltration technology based on the silent installation of an accessibility service

This work focuses mainly on the penetration test function and stability of Android smartphones under Kali 2019 and creates a stable penetration function of Android smartphones to form a strong reverse transmission control protocol connection. Using the silent installation technology supported by the Accessibility Service (integrated on a nontoxic functional platform), the Android Package that injects the penetration function successfully bypasses the common mobile phone antivirus software on the market to improve the penetration efficiency.

Reducing User Perceived Latency in Smart Phones Exploiting IP Network Diversity

The Fifth Generation (5G) wireless networks set its standard to provide very high data rates, Ultra-Reliable Low Latency Communications (URLLC), and significantly improved Quality of Service (QoS). 5G networks and beyond will power up billions of connected devices as it expands wireless services to edge computing and the Internet of Things (IoT). The Internet protocol suite continues its evolution from IPv4 addresses to IPv6 addresses by increasing the adoption rate and prioritizing IPv6. Hence, Internet Service Providers (ISP's) are using the address transition method called dual-stack to prioritize the IPv6 while supporting the existing IPv4. But this causes more connectivity overhead in dual-stack as compared to the single-stack network due to its preference schema towards the IPv6. The dual-stack network increases the Domain Name System (DNS) resolution and Transmission Control Protocol (TCP) connection time that results in higher page loading time, thereby significantly impacting the user experience. Hence, we propose a novel connectivity mechanism, called NexGen Connectivity Optimizer (NexGenCO), which redesigns the DNS resolution and TCP connection phases to reduce the user-perceived latency in the dual-stack network for mobile devices. Our solution utilizes the IP network diversity to improve connectivity through concurrency and intelligent caching. NexGenCO is successfully implemented in Samsung flagship devices with Android Pie and further evaluated using both simulated and live-air networks. It significantly reduces connectivity overhead and improves page loading time up to 18%.

Enhancing Fast TCP’s Performance Using Single TCP Connection for Parallel Traffic Flows to Prevent Head-of-Line Blocking

Hypertext Transfer Protocol-2 (HTTP/2) partially resolved the problem of Head-of-Line Blocking (HoLB) by multiplexing independent messages at the application layer. This enables simultaneous transmission of multiple requests over the same connection independently. However, this technique becomes ineffective when packet loss occurs in the Transmission Control Protocol (TCP) flow in which case all the independent streams are blocked until the retransmission of the lost packet; this problem is known as HoLB at TCP-level. The problem arises because the underlying TCP does not differentiate between independent messages/streams from application layer protocol. This study proposes a multistream framework for Fast TCP to support multiple independent messages/streams of the application. The proposed framework uses separate flows, buffers, and segments for each independent stream, and interleaves these segments over a single TCP connection. It makes TCP compatible with HTTP/2, reduces data delivery latency between transport and application layer, and alleviates head-of-line blocking. We implemented this framework in Fast TCP and carried out a simulation-based comparison between Multistream Fast TCP (MFast TCP) and Stream Control Transmission Protocol (SCTP). Our results show that MFast TCP significantly improved performance over SCTP in the event of HoLB.

Modelling and analysis of TCP congestion control mechanisms using stochastic reward nets

Modelling of congestion control mechanisms of the transmission control protocol (TCP) helps to obtain parametric results that help to better understand the TCP behaviour under different operating conditions. Several analytical models were proposed to analyse the behaviour of TCP congestion control mechanisms. However, most of these models were designed for a few TCP sessions with non-persistent connections. A few analytical studies were presented for modelling persistent TCP connections. Nevertheless, these studies have many limiting assumptions and are not scalable. In this work, a stochastic reward nets model is introduced for the TCP Reno with the persistent TCP connections, which share two bottleneck links in a wide area network. A microscopic approach was used for constructing the proposed model that captures most features of congestion control mechanisms used by the TCP Reno, and interactions between different TCP sessions. The proposed model relaxed several limiting assumptions adopted by other related models introduced in the literature. To validate the proposed model, analytical results are extensively compared with simulation results.

Congestion Window Scaling Method to Optimize Delay in TCP/IP

TCP (Transmission Control Protocol) is a protocol of layer four (Transport Layer), and IP (Internet Protocol) is in the Network Layer (Layer 3) of the OSI Model. The TCP protocol is the most used of the network applications on the Internet. TCP performance is strongly influenced by its congestion control algorithms that limit the amount of transmitted traffic based on the estimated network capacity and utilization. TCP is a connection-oriented protocol which guarantees the sent packets to the destination in accurate order whereas UDP is an unreliable/connectionless protocol which does not guarantee that the sent messages would reach the destination. A TCP connection is used to control packet sizes, the rate of data exchange, flow control and network congestion. Unfortunately, congestion/network overload happens in the TCP connection which affects the rate of data flow, loss in packets transmitted, packet transmission delay and delayed acknowledgment. In this paper, a method to scale the congestion window on the sender and receiver to optimize the delay of transmission in TCP in order to reduce the congestion rate is proposed. The proposed congestion control algorithm enables a sender to optimize and initialize the congestion window before transmitting packets. The proposed method is evaluated by simulating the transmission in Network Simulation 3 (NS3).

Off-Path TCP Exploits of the Challenge ACK Global Rate Limit

In this paper, we report a subtle yet serious side channel vulnerability (CVE-2016-5696) introduced in a recent transmission control protocol (TCP) specification. The specification is faithfully implemented in Linux kernel version 3.6 (from 2012) and beyond, and affects a wide range of devices and hosts. In a nutshell, the vulnerability allows a blind off-path attacker to infer if any two arbitrary hosts on the Internet are communicating using a TCP connection. Further, if the connection is present, such an off-path attacker can also infer the TCP sequence numbers in use, from both sides of the connection; this in turn allows the attacker to cause connection termination and perform data injection attacks. We illustrate how the attack can be leveraged to disrupt or degrade the privacy guarantees of an anonymity network such as Tor, and perform web connection hijacking. Through extensive experiments, we show that the attack is fast and reliable. On average, it takes about 40 to 60 s to finish and the success rate is 88% to 97%. Finally, we propose changes to both the TCP specification and implementation to eliminate the root cause of the problem.

The Comparative Study Some of Reactive and Proactive Routing Protocols in the Wireless Sensor Network

The wireless sensor network (WSN) consists mostly of a large number of nodes in a large area where not all nodes are directly connected. The applications of comprise a wide variety of scenarios.The mobile nodes are free to move because this network has selfــstructured topology. Routing protocols are responsible for detecting and maintaining paths in the network, and it classified into reactive (OnـــDemand), proactive (Table driven), and hybrid. In this paper represents a performance study of some WSN routing protocols: the Dynamic Source Routing (DSR), Ad hoc On-Demand Distance Vector (AODV), and Destination-Sequenced Distance-Vector (DSDV). The comparison made according to important metrics like packet delivery ratio (PDR), total packets dropped, Average end-to-end delay (Avg EED), and normalized routing load under the Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) traffic connection and with varying number of nodes, pause time; and varying speed. In this work used (NSــ2.35) that installed on (Ubuntu 14.04) operating system to implementing the scenario. Conclude that the DSR has better performance in TCP connection; while the DSDV has better performance in UDP protocol.

Tuning the Aggressive TCP Behavior for Highly Concurrent HTTP Connections in Intra-Datacenter

Modern data centers host diverse hyper text transfer protocol (HTTP)-based services, which employ persistent transmission control protocol (TCP) connections to send HTTP requests and responses. However, the ON/OFF pattern of HTTP traffic disturbs the increase of TCP congestion window, potentially triggering packet loss at the beginning of ON period. Furthermore, the transmission performance becomes worse due to severe congestion in the concurrent transfer of HTTP response. In this paper, we provide the first extensive study to investigate the root cause of performance degradation of highly concurrent HTTP connections in data center network. We further present the design and implementation of TCP-TRIM, which employs probe packets to smooth the aggressive increase of congestion window in persistent TCP connection and leverages congestion detection and control at end-host to limit the growth of switch queue length under highly concurrent TCP connections. The experimental results of at-scale simulations and real implementations demonstrate that TCP-TRIM reduces the completion time of HTTP response by up to 80%, while introducing little deployment overhead only at the end hosts.

TiD—Introducing and Benchmarking an Event-Delivery System for Brain–Computer Interfaces

In this paper, we present and analyze an event distribution system for brain-computer interfaces. Events are commonly used to mark and describe incidents during an experiment and are therefore critical for later data analysis or immediate real-time processing. The presented approach, called Tools for brain-computer interaction interface D (TiD), delivers messages in XML format via a buslike system using transmission control protocol connections or shared memory. A dedicated server dispatches TiD messages to distributed or local clients. The TiD message is designed to be flexible and contains time stamps for event synchronization, whereas events describe incidents, which occur during an experiment. TiD was tested extensively toward stability and latency. The effect of an occurring event jitter was analyzed and benchmarked on a reference implementation under different conditions as gigabit and 100-Mb Ethernet or Wi-Fi with a different number of event receivers. A 3-dB signal attenuation, which occurs when averaging jitter influenced trials aligned by events, is starting to become visible at around 1-2 kHz in the case of a gigabit connection. Mean event distribution times across operating systems are ranging from 0.3 to 0.5ms for a gigabit network connection for 106 events. Results for other environmental conditions are available in this paper. References already using TiD for event distribution are provided showing the applicability of TiD for event delivery with distributed or local clients.

On detecting TCP path saturation in LTE networks

SummaryA significant part of the data in mobile networks is transferred as bulk data with transmission control protocol (TCP) as apps or video downloads. When the video takes too long to start, users are more prone to abandon watching, which eventually leads to decreased revenue for the content provider. While it is widely known that TCP has performance issues in mobile networks, end‐to‐end measurement studies, especially based on real data, should be studied further.In this paper, we measure the efficiency of TCP in long term evolution (LTE) networks and provide an analysis on the reasons of unoptimal performance based on 235 000 measurements from deployed mobile networks. For this purpose, we propose an algorithm for LTE networks that detects the periods during a TCP connection where the path is saturated, ie, the network is the limiting factor. From this data, we find that TCP is a source for unoptimal performance, and assumed reasons from other papers are partly confirmed and partly refuted. Most importantly, we find that the amount of queueing on the path has significant impact on the achieved protocol performance. Lastly, we learn from the LTE experience and put the findings into a 5G context.

Analytical Modeling of Multipath TCP Over Last-Mile Wireless

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.