The Modulation Coding Scheme (MCS) index is a metric based on several parameters of a WiFi connection between two stations. Namely, for 802.11ac, it depends on the modulation type, the coding rate, the number of spatial streams, the channel width, and the guard interval. Here is what each one of…
We’ve talked about several testing utilities in the past such as ping, traceroute, iperf, and others. And every so often a new one pops into my radar, and I keep repeating “How come I didn’t know about this already?” In this case, the utility in question is nping. There are…
Telecommute The current work-from-home reality due to COVID-19 got me thinking about the history of the remote work trend. I believe most of us remember that two decades ago this used to be called “telecommute.” The combination of a reliable and widespread Internet with the SaaS tools revolution, such as…
We’ve talked about Linux tools that enable you to manipulate kernel networking parameters such as TCP window size and packet loss or latency. These kinds of tools are used when trying to optimize or troubleshoot network traffic either at the application or kernel level. When it comes to measuring the…
COVID-19 forced an overnight shift upon us which facilitated a world-wide “work from home” for as many employees as deemed necessary and feasible. The initial hurdle for each IT department was to set up the basics to enable employees to get their work done – VPN tunneling was among them. …
There are a few open-source and free tools out there that can help visualize the path traversed between two hosts. We’ve talked about mtr and traceroute, and recently I came across Dublin traceroute. Actually, the inventor of Dublin traceroute maintains his own blog here, and there you can find many…
We have talked about how to use nmap to detect the OS of a remote host. Nmap does that by sending probing packets and depending on the responses may or may not be able to identify the remote OS with a certain accuracy. That can work well in many cases,…
There are multiple ways to get a file from a remote Linux host. To name a few: scp, sftp, tftp, http/https… And you could probably add more in the list. Depending on your requirements in terms of security, ease of use, availability, and set-up effort you have to decide what…
mtr stands for “My Traceroute” and, in a nutshell, it’s traceroute on steroids. They both work the same way: a host sends probing packets to routers, measures and reports latency and packet loss. mtr takes that to the next level by giving you the ability to run the probe packets…
We have talked about the differences between iPerf2 and iPerf3 in terms of their reverse options. I recently noticed that the latest iPerf3 version 3.7 released on 06/21/2019 has an additional option to handle reverse testing, and I wanted to talk about it. Installation It takes a while for a…
