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Passkey when changing username
Posted: Thu Sep 29, 2011 6:18 pm
by Im_A_PC
Do I need to request a new passkey if I change my username, or can I continue to use the one I have been folding under?
Thanks!
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 7:16 pm
by PantherX
Welcome to the F@H Forum Im_A_PC,
You don't have to but you will need to re-qualify for the bonus points with the new combination of New username and same passkey. For more information, please read this
Quick Return Bonus (QRB) Plan Qualification
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 7:59 pm
by Im_A_PC
So if I understand correctly, even with a new passkey, I would have to re-qualify. So if I have already submitted more than 8 WU's under the QRB time, just stick with what I have?
Thanks for your quick reply!
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 8:10 pm
by Jesse_V
Im_A_PC wrote:So if I understand correctly, even with a new passkey, I would have to re-qualify. So if I have already submitted more than 8 WU's under the QRB time, just stick with what I have?
Thanks for your quick reply!
See this page
http://folding.stanford.edu/English/FAQ-passkey The passkey is tied to your username and email address. You cannot transfer credit or anything to your new username/passkey combo, so you will have to regain the QRB qualifications.
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 8:16 pm
by gwildperson
If you change EITHER your passkey or your UserName, you will have to complete 10 more units before you get a bonus. Since you said you were changing your user name, it doesn't really matter whether you change your passkey at the same time or not, at least in terms of QRB. When searching the official site for points, however, you can search by passkey and if it didn't change, you can get a summary of all of the points accumulated under all of your usernames. That might be a good reason to keep the old passkey.
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 10:28 pm
by Joe_H
Searching by passkey may also show you work done by a complete stranger. That is what I found when I did that. I have never shared mine, so have to assume they are not necessarily unique. The combination of username and passkey is supposed to be unique.
Re: Passkey when changing username
Posted: Thu Sep 29, 2011 11:37 pm
by PantherX
Joe_H wrote:Searching by passkey may also show you work done by a complete stranger. That is what I found when I did that. I have never shared mine, so have to assume they are not necessarily unique. The combination of username and passkey is supposed to be unique.
The passkey is generated by the email address provided. However, I have never heard of this indecent before so you could please provide more details via PM or posting it here (depending on your preference)? It might be possible that you mistyped the passkey and it matched someone else’s (rare but plausible). Did you try copy and pasting it directly from the email that you received?
Re: Passkey when changing username
Posted: Fri Sep 30, 2011 12:01 am
by 7im
A passkey is hashed on both the fah user name provided, and the email address provided when requesting the passkey. Passkeys are unique, even case sensitive to the name and email provided.
Re: Passkey when changing username
Posted: Fri Sep 30, 2011 3:41 am
by Joe_H
Details I will provide via PM, but yes the passkey was copy and pasted from the email. This was during my set up of the V7 Beta on my main folding Mac, so I am quite certain it was an exact copy. But having worked in computers for over 30 years, this is not the first time I have come across hashes that gave the same result to two different sets of input. Particularly nasty when that hash is part of a password store.
Re: Passkey when changing username
Posted: Fri Sep 30, 2011 5:40 pm
by 7im
I don't doubt that hashes used by other software programs in the past have had problems.
And I can't say for sure that this can't happen with fah, only because the complete hash method is not published for obvious reasons, but very unlikely with a 32 digit alphanumeric code made from dual inputs.
Re: Passkey when changing username
Posted: Fri Sep 30, 2011 6:44 pm
by Joe_H
Mathematically you would need something much longer than a 32 character code. Unlikely, yes, but the math behind hashing is such that it is a non-zero probability. Look up the "pigeonhole principle". So far there are no known hashing algorithms that prevent all collisions. Better algorithms reduce, but do not eliminate the possibility of a collision.
Re: Passkey when changing username
Posted: Fri Sep 30, 2011 8:07 pm
by 7im
And non-zero probablity does not guarantee a hash collision either. There are many ways to reduce or prevent collision, including salting, bit flipping, etc. Also note that since Pande Group is storing the hashes for use with the stats system, then can also avoid collisions by not generating any duplicates, however unlikely a duplicate may be.
Here is a fun little tool for people to play with...
http://www.fulcrum.com/Using_Computer_Hash.htm