Certainly true, but doesn't necessarily invalidate my comment. The zip format is an interesting case and it would be of (academic) interest to know if Phil Katz used a 32 bit CRC after researching alternatives - or simply because CRCs are widely used.
On the other hand, if you get a bit error in compressed data then the Deflate algorithm will tend to replicate and magnify the error as it decompresses the message resulting in a very different outcome to the original message. Hence any half decent checksum whether CRC or otherwise should pick up the error. On 01/09/14 10:29, Michael Schnell wrote: > On 09/01/2014 10:12 AM, Tony Whyman wrote: >> CRCs only >> really have the edge with communications because the error pattern is >> typically known for a given communications medium and the CRC can be >> tuned to the media in order to give better performance. > Even in software-only applications, CRCs are used rather ubiquitously. > e.g. ZIP uses CRC 32. > > -Michael > _______________________________________________ > fpc-pascal maillist - [email protected] > http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal _______________________________________________ fpc-pascal maillist - [email protected] http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
