Ping is one of the oldest and also most commonly used utilities for network testing and troubleshooting. We’ve talked about ping before and we’ve also talked about similar utilities such as nping and hping3. Ping Output What ping does (sending ICMP echo requests and measuring latency by reading the ICMP reply)…
If you google something like “find my public IP,” you will probably find dozens of websites that as soon as you open them display your public IP such as this one: It may also give you the geographical location of your IP, but even if they don’t, it’s as easy…
Traceroute gives you the hop-by-hop information of a route from a source host to a destination. In most cases getting the IP and maybe its DNS lookup (when available) is enough for troubleshooting purposes. Nmap is another tool that I’ve been using a lot lately. It’s very well known in…
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,…
