The birthday-attack tag has no wiki summary.
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Is the likelihood of a birthday collision linear (evenly distributed) for all ciphers? When are they not?
When discussing the Birthday Principal, in combination with the pigeon hole principal, it was argued that an uneven distribution of birthdays (bias for September and any Tuesday of the year) made ...
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How does a birthday attack on a hashing algorithm work?
A "normal", brute-force attack on a cryptographic hashing algorithm $H$ should have a complexity of about $2^{n}$ for a hash algorithm with an output length of $n$ bits.
That means it takes about ...
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Why would you expect to find a collision in a hash function after approximately $\sqrt{n}$ hashes?
I can't get an intuitive understanding of why it's $2^{(\frac{n}{2})}$ and not $2^n$, where $n$ is the number of bits of which the key consists.
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Security of N bit HMAC
Lets say that I am using 128 bit HMAC. How many operations are needed to find "non secure" message. Is birthday attack possible?
