networking - How are IP packets reassembled -


let's have ip packet total size of 12000 bytes , send packet station station b on data-link layer. single ethernet frame can carry 1500 bytes of payload data, in total, need 8 ethernet frames transmit 12000 bytes ip packet, correct?

let's assume first ethernet frame (carrying ip header) gets garbled during transmission , totallength field of ip header no longer contains actual length nonsense value. if station b realizes header checksum no longer valid , discards frame, how can station b know next ip packet starts in incoming data stream? not know how many bytes of payload first ip packet had, right?

or size of ip packet limited maximum length of payload underlying data-link frame can handle?

okay after doing more researching, case maximum size of ip packet determined maximum transmission unit (mtu) of data-link.

for care, website breaks down pretty well: http://aa.net.uk/kb-broadband-mtu.html


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