[radext] Eric Rescorla's No Objection on draft-ietf-radext-coa-proxy-05: (with COMMENT)

[Eric Rescorla <[e-mail]>]

Eric Rescorla has entered the following ballot position for
draft-ietf-radext-coa-proxy-05: No Objection

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COMMENT:
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Rich version of this review at:
https://mozphab-ietf.devsvcdev.mozaws.net/D5085


I concur with Adam's DISCUSS (but marking no-objection to let him
manage this). Specifically, you need to describe what the security
expectations are for the Operator-NAS-Identifier. Need it be
unguessable? Should separate identifiers that refer to the same NAS be
unlinkable? "Cryptographically strong" is not a sufficiently specific
term to determine what the requirements are here.

COMMENTS
S 6.
>      issues.
>   
>      The Operator-NAS-Identifier SHOULD be created by the Visited Network
>      such that its contents are opaque to all other parties.  This ensures
>      that anyone observing unencrypted RADIUS traffic gains no information
>      about the internals of the Visited Network.

See above about the requirements here. Does there need to be an
unlinkable identifier each time?