ATM (asynchronous transfer mode) is the technology chosen for the Broadband Integrated Services Digital Network (B-ISDN). The ATM ABR (available bit rate) service can be used to transport ``best-effort'' traffic. In this paper, we extend our earlier work on the buffer requirements problem for TCP over ABR. Here, a worst case scenario is generated such that TCP sources send a burst of data at the time when the sources have large congestion windows and the ACRs (allowed cell rates) for ABR are high. We find that ABR using the ERICA+ switch algorithm can control the maximum queue lengths (hence the buffer requirements) even for the worst case. We present analytical arguments for the expected queue length and simulation results for different number of sources values and parameter values.
Improving the Performance of TCP over the ATM-UBR service
在本文中，我们研究的设计问题，在提高TCP性能的ATM UBR服务。ATM-UBR交换机通过在缓冲区满时丢弃信元来响应拥塞。在UBR上运行的TCP连接可能会遇到低吞吐量和高不公平性。智能交换机丢弃策略和端系统策略可以在有限缓冲区的情况下提高TCP over UBR的性能。我们描述了各种设计选项，可用于网络以及终端系统，以提高TCP性能的UBR。我们研究了早期数据包丢弃的影响，和两个每VC会计为基础的缓冲区管理政策。我们还研究了各种TCP端系统拥塞控制策略的效果，包括慢启动和拥塞避免，快速恢复和恢复以及选择性拥塞。我们提出了各种小的和大的延迟配置不同的缓冲区大小和数量的源的模拟结果。
A low and stable buffer occupancy is critical to achieve high throughput, low packet drop rate, low latency, and low jitter for data center networks. It also allows switch chips to support higher port density, larger lookup tables, or richer functions. Tiny Buffer TCP creatively uses the common RED-based ECN with two novel congestion-window adjustment schemes to significantly reduce the required buffer size. Aiming to eliminate the residual packets in the bottleneck queue, Queue Canceling Decrease amortizes the ideal window reduction to the same number of flows so as to minimize the impact to …
Improve performance of tcp new reno over mobile ad-hoc network using abra
在移动自组织网络中，临时链路故障和路由变化频繁发生。假设所有的数据包丢失都是由于拥塞，TCP在这样的环境中表现很差。有许多版本的TCP，根据需要随时修改。本文通过计算新重传超时（RTO），对移动ad-hoc网络上的TCP New Reno协议进行了改进，以提高拥塞控制的性能。为了计算新RTO，应用TCP New Reno中的自适应退避响应方法（ABRA），其建议ABRA New Reno。它利用了一个ABRA拥塞窗口和慢启动阈值减少，每当收到一个确认和新的退避值计算平滑的往返时间。基于ABRA New Reno与其他TCP变体（如New Reno和Reno）的比较研究，使用实际参数（如TCP数据包接收，数据包丢弃，数据包重传，吞吐量和数据包传输率）进行了评估，这些参数是通过改变节点速度，节点数量和传输时间的属性计算的。在QualNet 4.0模拟器中进行实施和模拟。
The design of transport protocols, embedded in end-systems, and the choice of buffer sizing strategies, within network routers, play an important role in performance analysis of the Internet. In this paper, we take a dynamical systems perspective on the interplay between fluid models for transport protocols and some router buffer sizing regimes. Among the flavours of TCP, we analyse Compound, as well as Reno and Illinois. The models for these TCP variants are coupled with a Drop-Tail policy, currently deployed in routers, in two limiting regimes: a small and an intermediate buffer regime. The …
We study TCP flows coexistence between Massive Multiplayer Online Role Playing Games (MMORPGs) and other TCP applications, by taking World of Warcraft (WoW) and a file transfer application based on File Transfer Protocol (FTP) as an example. Our focus is on the effects of the sender buffer size and FTP cross-traffic on the queuing delay experienced by the (MMORPG) game traffic. A network scenario corresponding to a real life situation in an ADSL access network has been simulated by using NS2. Three TCP variants, namely TCP SACK, TCP New Reno, and TCP Vegas, have been considered for cross-traff…
Routers have packet buffers to reduce packet drops during times of congestion. It is important to correctly size the buffer: make it too small, and packets are dropped unnecessarily and the link may be underutilized; make it too big, and packets may wait for a long time, and the router itself may be more expensive to build. Despite its importance, there are few guidelines for picking the buffer size. The two most well-known rules only apply to long-lived TCP Reno flows; either for a network carrying a single TCP Reno flow (the buffer size should equal the bandwidth-delay product, or $BDP$) or …
Recent advances in high-speed mobile networks have revealed new bottlenecks in ubiquitous TCP protocol deployed in the Internet. In addition to differentiating non-congestive loss from congestive loss, our experiments revealed two significant performance bottlenecks during the loss recovery phase: flow control bottleneck and application stall, resulting in degradation in QoS performance. To tackle these two problems we firstly develop a novel opportunistic retransmission algorithm to eliminate the flow control bottleneck, which enables TCP sender to transmit new packets even if receiver's rece…
Since current widely available network protocols/systems are mainly throughput-oriented designs, meeting stringent delay requirements of new applications such as virtual reality and vehicle-to-vehicle communications on cellular network requires new network protocol/system designs. C2TCP is an effort toward that new design direction. C2TCP is inspired by in-network active queue management (AQM) designs such as RED and CoDel and motivated by lack of a flexible end-to-end (e2e) approach which can adapt itself to different applications' QoS requirements without modifying any network devices. It co…
Adaptive Bitrate (ABR) Streaming over the cellular networks has been well studied in the literature; however, existing ABR algorithms primarily focus on improving the end-users' Quality of Experience (QoE) while ignoring the resource consumption aspect of the underlying device. Consequently, proactive attempts to download video data to maintain the user's QoE often impact the battery life of the underlying device unless the download attempts are synchronized with the network's channel condition. In this work, we develop EnDASH-5G -- a wrapper over the popular DASH-based ABR streaming algorithm…
Middleboxes such as web proxies, firewalls, etc. are widely deployed in today's network infrastructure. As a result, most protocols need to adapt their behavior to co-exist. One of the most commonly used transport protocols, QUIC, adapts to such middleboxes by falling back to TCP, where they block it. In this paper, we argue that the blind fallback behavior of QUIC, i.e., not distinguishing between failures caused by middleboxes and that caused by network congestion, hugely impacts the performance of QUIC. For this, we focus on YouTube video streaming and conduct a measurement study by utilizi…
