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My guess as to why they still use SHA-1 is that they want to interoperate with some existing systems and browsers that do not support SHA-256 yet. … When the whole World has switched to SHA-256, and all firewalls have been updated, the path becomes clear for Google, and they can use SHA-256 for their new certificates. …

SHA-1), Pb is a permutation of the space of sequences of exactly n bits (n = 128 for MD5, n = 160 for SHA-1). … (In the case of MD5 and SHA-1, that addition is done on a 32-bit word basis, but the details do not matter here.) …

Hash functions are deterministic: same input yields the same output. Any implementation of a given hash function, regardless of the language it is implemented in, must act the same. However, note tha …

SHA-1, as a hash function, is known to be "slightly shaky". … However, the current fashion is to shoot SHA-1 on sight and insist on switching to one of the SHA-2 functions (e.g. SHA-256 or SHA-512) systematically. …

If you want to stick to PBKDF2, using SHA-512 would be a good idea, because SHA-512 uses a lot of 64-bit arithmetic operations, something which a modern PC is very good at, but which GPU suck at. … ASIC specialized in SHA-256 do not change that recommendation. …

PBKDF2 and bcrypt are configured with an "iteration count", which means that they can be made as slow as you want. Therefore, there cannot be a table which shows how fast they go. What you need to do, …

As others have responded, hash functions (all of them, including MD5, SHA-256, Whirlpool and the dozens of other functions) output bits. The output of MD5 is 128 bits. …

RSA-2048, ECDSA (on a 256-bit curve), SHA-1, SHA-256 and AES-256 are all "equally" uncrackable in that they are all in the wide category of "we don't know how to break them with existing or foreseeable … -1 (2160), then SHA-256 and AES-256 (2256). …

MD5 and SHA-1 have flaws with regards to collisions (in the case of SHA-1, these flaws are "theoretical" in that no actual collision has been produced yet). … Right now, nobody knows how to do that with a RSA/SHA-1 signature (or, for that matter, with a RSA/MD5 signature). …

"Believe" is the right word: we already know that MD5 (or SHA-1 or SHA-256) is not a random oracle (the length extension attack is enough to show it, and it can even be proven that it is not ultimately …

New protocols should rely on better hash functions (like SHA-256), but there is no use in breaking existing protocol by evicting a still serviceable MD5. …

This does not mean that SHA-1 should not be avoided. In fact you already should not use it in new systems, and strive to implement support for SHA-256 anywhere. But you should not panic. … The current fashion of placing an anathema on SHA-1 should be understood politically, not cryptographically. The situation on SHA-1 has not substantially changed in the last four years. …

There is no known property of the first/last/middle/whatev 60 bits of a SHA-256 output that would make them more/less "randomish" than the last/whatev/middle/first 60 bits. … Is is possible that the inherent UUID generation system of your local programming environment relies on a cryptographically secure PRNG (so hashing an UUID with SHA-256 would then be fine, even for unpredictability …

Thus, there can be no such thing as "one-way encryption", and SHA-1 is not encryption. … SHA-1 is hashing: no key, fixed-size output (160 bits for SHA-1), no reverse process (in particular, the input can be quite larger than the 160 output bits). …

No such attack is known for SHA-1 right now; if somebody wanted to compute such a second preimage, he would have to pay a cost of about 2160 hash function computations, which is way beyond that which is …