[AFS3-std] Re: rxgk CombineTokens and enctypes

[Andrew Deason]

On Tue, 6 Nov 2012 20:39:08 -0500 (EST)
Benjamin Kaduk <kaduk@MIT.EDU> wrote:

> > [After the lifetime, byte-life, etc fields are specified]
> > + The identity in the new "combined" token is an application-specific
> > + combination of the identities of the input tokens; note that this
> > + combination may not be commutative.
> 
> In particular the combined identity need not represent either the
> union nor intersection of the privileges associated with the two
> identities.  (Right?  I had asked rougly this question earlier but I
> don't think I got a reply.)

Yes (as I understand it). At first I put in a couple of examples, but I
thought that might be too wordy and not necessary. I originally wrote
something like:

+ The identity in the new "combined" token is an application-specific
+ Combination of the identities of the input tokens. For example, an
+ Application may define the identity of the combined token to be the
+ Union of the identities of the input tokens. However, an application may
+ Instead define the combined token identity to represent the identity of
+ Token0 to be acting in an environment represented by the identity of
+ Token1, or some other complex or application-specific meaning. This
+ Combined identity may or may not be representable as a simple set or
+ List, and may or may not be commutative. An application may also
+ define application-specific variants of the CombineTokens RPC to utilize
+ multiple different token combinations, or to utilize additional
+ application-specific input and/or output parameters.

I don't know how much of that text is really necessary or even helpful,
but that's how I'm thinking about it.

-- 
Andrew Deason
adeason@sinenomine.net