MTU over 1500 on WLAN ?

Hi!

WLAN packets are supposedly about 2300 bytes long, but usually
the user data size is about 1500 bytes.
Is the difference 2300-1500 some kind of protocol overhead ?
Could MTU larger than 1500 be used ?

Thanks for any reply,
David Bala¾ic

PS: Sending this for the third time, hopefully it makes it to the list.

----------------------------------------------------------------
VOLJADSL Paketi po vasi meri. Hitri internet od 2.990 SIT in hitrosti do 20 Mb/s.
http://adsl.volja.net