Difference between MTU (maximum transmission unit for a TCP/IP packet) versus the fragmentation threshold setting when using 802.11 networks?
They're mutually exclusive from each other. Fragment threshold is access-point centric (802.11), MTU is IP header based..... Difference between layer2 and layer3 in a nutshell. Yes, fragment threshold can be above MTU, and MTU can be above fragment threshold. A bit more detail below if you wish to read. Fragmentation threshold is between your access point and you. If your MTU is lower than your fragment threshold then YOU WILL NEVER see 802.11 fragments. If your MTU is higher than your frag threshold, AND the payload is large enough then your access-point will force a fragment and the frame will be split up between host and AP to be reassembled upon delivery. You generally want your MTU to be whatever the maximum MTU is of your AP/LAN/Internet connection. This is generally 1500 bytes, however in some cases where PPPOE/ATMOE/VPLSOE or other carrier-to-carrier encapsulation is used. Why would you want fragmentation? The only reason you would be interested in ...
