Hi, This is incorrect if the packet is transmitted over IPv4. All packets are subject to fragmentation over IPv4 and governed by smallest MTU in the route. Note that if the DF bit is set the router will *not* fragment the packet and will instead send back an IMCP response containing the message "fragmentation needed and DF set". It would be correct to say that routers on an ipv6 network do not fragment and instead the MTU is honored at both receiving end points due to PMTUD. Best Wishes, -David Delaune