yikuang / wave-protocol

Automatically exported from code.google.com/p/wave-protocol
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document-id susceptible to collision issues #15

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago
Currently, document-ids do not include enough information to guarantee them 
to be unique.  This could (not likely, but could) result in collisions when 
document creating operations are submitted to the authoritative Federation 
Host from multiple sources.

Suggested solutions so far are:

1) Include the domain of the submitting host in the document-id.  This 
guarantees no collisions.

2) Require document-ids to be at least a certain length, to make collisions 
much less likely.

Original issue reported on code.google.com by mac...@gmail.com on 10 Jun 2009 at 4:16

GoogleCodeExporter commented 9 years ago
Personally, I'd prefer domains to be added to the document-id.  Both cases are 
going to 
make the id longer, why not go with the one that guarantees no collisions?

Original comment by mac...@gmail.com on 10 Jun 2009 at 4:17

GoogleCodeExporter commented 9 years ago

Original comment by so...@google.com on 11 Jun 2009 at 12:16

GoogleCodeExporter commented 9 years ago
Adding the domain doesn't help with collisions, since two users on the same 
domain 
could create new documents in the same remote wavelet. A solution might be to 
both 
expand the size of docids, and as an added helper, make the first part of the 
docid be 
based on part of the hash of user+domain.

Original comment by anthonybaxter@gmail.com on 16 Mar 2010 at 4:12

GoogleCodeExporter commented 9 years ago
As long as a domain is responsible for generating document-ids for documents 
created by 
its users and said domain is aware of all the document-ids it has generated 
within that 
wavelet, there will never be a collision.  There is the additional check of 
making sure 
the "random" part of the ID hasn't been used before, but all those IDs should 
be 
available to check because the domain only has to check the documents created 
by its 
users.

Original comment by mac...@gmail.com on 27 Apr 2010 at 10:16

GoogleCodeExporter commented 9 years ago
There are no explicit document-creating operations, and they don't "collide". 
OT just resolves everything so that both contributions are reflected. Of course 
this may not always be desired but it's merely an extension of the properties 
that apply within a document. Document creators are free to add a domain to the 
ids if desired.

I'm not convinced this is an issue we should fix.

Original comment by ano...@google.com on 14 Sep 2010 at 11:44

GoogleCodeExporter commented 9 years ago

Original comment by ano...@google.com on 14 Sep 2010 at 11:44