Iperf3 OverviewCommon Used Parameters for both TCP and UDPTCP Network Performance TestingUDP Network Performance Testing Iperf3 Overview Iperf3 is a tool for performing network performance testing. It allows you to test the bandwidth, latency, and packet loss across network links by sending and receiving streams of data between two hosts. iperf3 operates in a client-server …
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wrk is a high-performance HTTP benchmarking tool that is designed to measure the performance of web applications and APIs. It is a flexible and customizable tool that allows users to simulate real-world scenarios and test the performance of their web servers under various loads. wrk is easy to use and can be run from the …
Useful Wireshark filter for analysis of SSL Traffic. Client Hello: ssl.handshake.type == 1 Server Hello: ssl.handshake.type == 2 NewSessionTicket: ssl.handshake.type == 4 Certificate: ssl.handshake.type == 11 CertificateRequest ssl.handshake.type == 13 ServerHelloDone: ssl.handshake.type == 14 Note: "ServerHellpDone" means full-handshake TLS session. Cipher Suites: ssl.handshake.ciphersuite I found the below from Wiki. All these SSL handshake message types …
Vyatta 5600 provides Tshark as the packet capture tool. To capture your interested traffic and remove unnessary nosiy traffic, you need to use the capture filter when you perform the packet capture. Here I show you a few real world example for tshark capture filter, which hope can save you a bit of time. Capture …
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Symptom: customer complains about slow response to SSH server running on one Centos box Method: perform packet capture on the SSH server. Finding: DNS query fails during establishing SSH session When folllow the TCP session for SSH login packet caoture, see the below: During packet 17 and 24, there is about 10 seconds gap. Go …
Continue reading Packet Analysis for Troubleshooting-SSH server slow response
Symptom: virtual desktop end users complain the performance issue: the end users can access their AD home directory quickly at the first time. After a little while, they have to wait for over 30 seconds before they can reach their home directory. Method: perform packet capture on one of end users and successfully capture the …
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Firstly, what's LFN? LFN means long fat network, often pronounced "elephan". In RFC 1072, a network is considered an LFN if its bandwidth-delay product is significantly larger than 105 bits (12500 bytes). Then you will possibly have another question: what bandwidth-delay product is? As Wiki suggested, bandwidth-delay product refers to the product of a data …
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