Español
Deutsch
Since different network segments along a path can have different MTU limits, Path MTU Discovery automatically finds the smallest limit along the entire route.
How It Works
A sending device starts with an assumed packet size and reduces it based on feedback from routers along the path that reject packets exceeding their own limit, until it finds a size the whole path accepts.
When It Fails
Some firewalls block the diagnostic messages this process depends on, causing large transfers to fail mysteriously — a known, sometimes tricky networking issue to diagnose.
