Ethernet uses a sliding window to resend lost frames (error correction). It uses a sequence number to account for unordered frames (error correction). It has a frame check sequence to discard corrupted frames (error detection). Does this makes it "reliable"?

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    Your information is wrong. Ethernet doesn't resend lost frames nor does it use sequence numbers. As such the basis for the question is invalid unless you would care to edit the question.
    – YLearn
    Jul 17 '14 at 15:13

Not even remotely. There are no mechanisms for signaling a dropped frame (or why it was dropped -- CRC error, too small ("runt"), too big, no buffer space), thus there is no means to know what needs to be resent. There are no sequence numbers in ethernet frames -- the payload may contain one.

The only time ethernet will resend a frame is when the transmitter knows a collision occurred. But with 99.99999% of gear being full duplex today, collisions never happen.

BTW, this is why iSCSI SANs use special switches with very large internal, per-port buffers. And why FCoE (fibre channel over ethernet) uses special hardware. Both require a reliable transport, and ethernet on it's own isn't.

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