Subnet Masks
A subnetwork, or subnet, is a logically visible, distinctly addressed part of a single Internet Protocol network. The process of subnetting is the division of a computer network into groups of computers that have a common,…
SI prefixes
An SI ⇒prefix is a name that precedes a basic unit of measure to indicate a ⇒decimal ⇒multiple or ⇒fraction of the unit. Each prefix has a unique symbol that is prepended to…
pcap filter
tcpdump and ngrep are both based on libpcap. Therefore both use the same filter expressions. Here is the manual page of the ⇒pcap filter expression. These filter expressions are also…
Network grep “ngrep” on macOS
Sometimes it is very practical to use grep, to find a specific regular expression in some files. It would also be very practical to have the grep functionality on the…
Delete Applications on a Mac
On a Mac, you basically pull your application, you do not want anymore, into your trash bin. That's it. But there are always some config files left in the ~/Library…
tcpdump TCP/IP packet sniffer
Sometimes you need a powerful sniffer on your system. Every Mac and every Linux system got it. You just have to use it. tcpdump The only thing you have to…