[Coco] Fwd: IP packets on my coco

[Barry Nelson]

 The problem with that approach is that an 8 bit CRC requires a 256 byte lookup table or 2^8 bytes. A 32 bit CRC would need a 2^32 byte table or 4294967296 bytes, that is a 4Gb lookup table.

> Dave Philipsen dave at davebiz.com 
> Wed Jun 8 01:27:51 EDT 2016
> I remember from the CRC calculation in X/Ymodem that there is an easy 
> and faster way to get the CRC using lookup tables.  That's how I did it 
> with Supercomm.  I believe the CRC for the networking packets is a 
> 32-bit CRC so I don't know if lookup tables are still practical or not 
> with that size CRC.  What is amazing is that I was able to find that 
> information without the internet back then.  I just now did a few 
> cursory searches on calculating CRCs and I'm guessing that there is a 
> fairly easy method that doesn't require so much overhead.
> 
> 
> Dave