The Transmission Control Protocol (TCP) detects packet loss and performs retransmissions to ensure reliable messaging. provide a simple formula that offers insight into the maximum TCP throughput on a single session when there is packet loss. Extreme UDP packet loss at 300Mbit (14%), but TCP > 800Mbit w/o retransmits. When troubleshooting the network there are three metrics used in assessing performance: latency, packet loss, and throughput. Here is a good link on how to calculate the throughput and delay product settings. Even a small loss rate can severly impact performance. If the congestion window decreased when a packet was lost, would it decrease the throughput (speed of the sending of packets from web server)? To calculate packet loss, depending on the type of traffic, you can either add up the tcp.retransmission and go from there. It will show the throughput for the entire file. Despite the maturity of network links to 10Gbps and beyond, packet loss is still an underlying network event that impacts applications today. ThroughputTCP ˇ p 1:5 MSS RTT p lossrate (1) Yes. Network packet loss: are we still coping with that today? Learn about how gauging these metrics will help assess the cause of an unstable and sluggish network in this video. Furthermore, the throughput of TCP is significantly impacted by packet loss ([3], [4]). Does RTO decreases or increases with each packet lost and does it also affect the decrease in the throughput? TCP Network Latency and Throughput Or ‘Why your customer doesn’t receive the Throughput they paid for’ TCP versus UDP Background Traditionally, video was carried over User Datagram Protocol (UDP). Mahesh, It would actually depend on various factors like Application (TCP vs UDP), window size, latency, packet loss etc . The MTU was set to 9000bytes. This way, TCP can detect if a packet goes missing and resend it accordingly, ensuring reliable transmission of data. Mathis, et al. The following formula ([5], [6]) for a simple TCP throughput modeling indicates that its throughput is inversely proportional to both RTT and the square root of loss rate. 1. UDP is a connectionless protocol. If you want to know throughput for some specific traffic, filter it first, then Statistics - Summary, then look in displayed packets. The Mathis equation states the for TCP Reno, the maximum throughput is bound by this formula: Note the with default MTUs of 1500, the impact of packet loss is even greater. The effect of packet loss on TCP throughput has been widely analyzed. TCP throughput = BDP / RTT = (Link Speed in Bytes/sec * RTT)/RTT = Link Speed in Bytes/sec This is correct only if the window size is configured to the optimal value. That formula is: Figure 1: Factors that Impact Throughput. Unstable throughput is typically caused by packet loss. 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