Robust FTP Path MTU Auto Discovery This setting is enabled by default. Enabling this setting causes TCP to attempt to discover the Maximum Transmission Unit (MTU or largest packet size) over the path to a remote host. Knowing the Path MTU and limiting the TCP segments to this specific size, the TCP protocol is supposed to be able to eliminate fragmentation of the packets at routers on the communication path that connects networks with different MTUs. In order for this to happen, the server side algorithm implementation has to be known, and also assumes all of the servers on the entire network only run MSFT server software with server- side optimization features accessible from MSFT web-browser client software. However; this is very unlikely. Accordingly; it is not recommended to disable this setting as it would then cause an MTU of 576 bytes to be used for all connections that are not to computers on the local subnet. Therefore; disabling this setting can cause severe performance degradation because fragmentation may not be compensated for.