Does Fragementation depend on IP or Ethernet MTU

Question

IP modules are not prepared to accept datagrams of more than 576 octects according to RFC791 and ethernet MTU is 1500 octets. Are packets fragmented according to Ethernet MTU or IP MTU.?

Answer 1

From what I'm reading, rfc791 requires 576 for an ip module as the "minimum" buffer size for an incoming ip packet/fragment.

    All hosts must be prepared to accept datagrams of up 
    to 576 octets (whether they arrive whole or in fragments).

IP Fragmentation in general is according to 1500 which is the default MTU of ethernet.

Beware that some vendors support ethernet jumbo frames which can go up to 64k in frame size.