Re: Cryptographic Hash function

"SecBoy" <secboy@xxxxxxxxxxxxxx> writes:

Newbie at crypto & security. So excuse me if my question
is naive.

As per what I have read, a cryptographic hash function
always produces a fixed length string as output. Does this
Usually. That is of course not a requirement but is the norm.

mean that the output string will always be longer than the

No. The output string is almost always shorter than the input.

input string? Because if not, then there will be collisions -
am I wrong?

Yes. There will be collisions. A hash is NOT an encryption. The whole
question is whether or not those collisions are easy to find or not. making
them hard to find is what makes a hash "cryptographic" or not.




If this the wrong forum for this kind of question, can someone
direct me to the right forum. Also I have other questions about
CA's & digital certificates for web servers.


.

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