See below.

> Section 3.2
>
> You make reference to the proper "TACACS+ Session", but there is no reference 
> either in your terminology section or to the T+ RFC.  I feel a reference is 
> needed here.

This is defined in rfc8907 S3.5 and S2 of the draft refers to 8907 S3.  Is
this not an acceptable way to do this?

[JC] It struck me as warranting a 2.x sub-section.

> Section 4
>
> "The TACACS+ server or client receiving TACACS+ Packets MUST process
>    the packet as if TAC_PLUS_UNENCRYPTED_FLAG was set.  The actual value
>    of TAC_PLUS_UNENCRYPTED_FLAG flag in the TACACS+ header MUST be
>    ignored."
>
> But what if the flag isn’t set and obfuscation is used?  That’s an error, and 
> MUST result in the termination of the Session (at least that’s what I would 
> think).  This should be clarified,

The sections says that the flag MUST be ignored on receipt and SHOULD set
on transmission.  I will attempt to make it clearer.

This seems like a common way to deprecate a flag.  Do you still think that
the unset flag on receipt should be an error?

[JC] I personally do as it could be that obfuscation is being done and this 
will ultimately lead to the inability to process the PDU.  That said, I’m more 
in favor of a strong obsolescence of the obfuscation.

> Overall, I think this document warrants an Operators Considerations section 
> to describe interoperability with legacy T+.  That is, thoughts around 
> configuring a fallback legacy T+ server along side a tacacss server (or 
> servers); thoughts on migrating from a shared key to certificate-based 
> validation; etc.
>
> You address some of this in different parts of the document where you talk 
> about PSKs, mixing legacy and tacacss on a single server, and the need to 
> provide some port flexibility, but I think a centralized section might help 
> bring focus to those migrating to this.

Sure, completely reasonable.  But I don't want to expend that effort unless
this will be adopted.  Seems like that could lead to quite a bit of
rearrangement.

> Additionally, if there are working or PoC implementations of this, some 
> lessons learned (perhaps in an appendix) could be useful.

There are none that I know of.  I would not make that effort unless there is
adoption or at least a commitment to adopt the draft.

[JC] As chair, I will call for adoption of this work by the WG.  I read Alan’s 
recent reply and understand how he feels concerning this approach to more of a 
straight TLS encap around T+.  I would like to hear what others in the WG 
think.</chair>

Joe
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