How to read, calculate and set MTU in Windows, Linux and OSX

After I released the MTU Optimizer, a small tool for determining the optimal MTU, some days ago, let’s look at how to determine the optimal MTU by hand, how to read the currently set MTU and how to set new MTU value now. Of course we will discuss the whole thing for the three major operating systems: Windows, OSX and Linux.
Before we look at the implementation within the individual operating systems, we first briefly clarify what the MTU is and how its optimal value can be calculated.
Theory – Identify ideal MTU
The MTU (Maximum Transfer Unit) describes the maximum packet size of a protocol. It therefore indicates the maximum size of a data packet, so that it can be transmitted via a protocol. If a data packet is larger, it becomes fragmented – i.e. divided into several packages.
For example, let’s assume that we (=PC) would have a factory for sugar packets and our packet […]

Tool: MTU-Optimizer – automatically find the best MTU

Today I would like to present you again a small tool from „own production“. The tool I’m talking about is called MTU-Optimizer. The name already gives an indication of what the tool can do for you: It determines the MTU (Maximum Transmission Unit) and can set it for any network card.
Like most of my tools, the MTU Optimizer is programmed in C# and designed as portable application. (This means: It does not require any installation and can be started, for example, from a USB flash drive.) The download link to the tool can be found at the end of this article. Beforehand, however, I would like to briefly discuss the capabilities of the tool. Therefore we should first have a look at what the MTU is all about.
What is MTU?
MTU is the abbreviation for Maximum Transmission Unit and is the maximum packet size within a protocol. If the data packetsize exceeds […]