Ethernet frame size - incosistency in books

Todd Lamle - CCNA Deluxe edition, 2005 print - page 28:

"... the size can vary from 64 to 1500 bytes" ==> no matter how I turn this, I can't figure out how the data(!!!) portion minimum size could be

64 bytes - I thought that was 48 bytes?!?

J. Scott Haughdall - Network Analysis and Troubleshooting - page 83:

"For Ethernet, the MTU must be at least 64 bytes (now this is min data (48

- wrong above)+ dest_addr(6) + src_addr(6) + crc(4)), and the maximum is

1518 bytes" ==> this time I can't figure out the 1518 - I thought the max was: dest_addr+src_addr+max_data+crc = 6+6+1500+4 = 1516 (similar to 6+6+48+4=64)?!?

So - am I correct assuming:

- data portion = 48 - 1500

- MTU = 64 - 1516 thus none of the two books being correct, or am I missing something here?!?

TIA, Papi

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papi
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Ethernet frame size can vary from 64 bytes to 1518 bytes. Ethernet MTU size can vary from 46 bytes to 1500 bytes. The 18 bytes difference = 6-byte Destination MAC address + 6-byte Source MAC address + 2-byte Type + 4-byte CRC.

KPLAB

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kplab

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