Re: [Pppext] Comment related to draft-ietf-pppext-trill-protocol-01.txt

[James Carlson <[e-mail]>]

Donald Eastlake wrote:
>>> In particular, does it cover the PPP Header, in which case I
>>> think it should be labeled "PPP FCS"? Or should the convention in PPP
>>> be to have an FCS just covering the encapsulated Ethernet frame?
>>>
>>> In any case, I think a few words about this are needed in the
>>> pppext-trill draft...
>> We don't normally do that for PPP documents -- it's assumed that the NCP
>> document just covers the bits that are particular to that NCP, and not
>> all of the common PPP bits all the way down to the bare metal -- but I
>> guess I can do that if it'll help with alignment with the other TRILL
>> documents.
> 
> Well, I would assume the RFC resulting from
> draft-ietf-pppext-trill-protocol will in some cases be read by people
> familiar with TRILL but not familiar with PPP. So, while it certainly
> doesn't need much, making it clear that there is no Ethernet FCS in
> the encapsulated material and having references pointing at the PPP
> Trailer info seem like a good idea to me.

I've made the updates for both -- making it clear that the Ethernet FCS
is not present and that the PPP FCS (if any) is used.  I'll send you a
draft to look over.

(I think that if they're reading this and don't know much about PPP, I
think they're probably in a world of hurt.  Or at least their customers
are going to be.  I'm not about to turn this simple draft into a road
map for implementation of PPP.)

>> (For what it's worth, I don't think the TRILL document should mention
>> the Ethernet FCS, either.  TRILL isn't defining Ethernet encapsulation,
>> and including those bits seems like duplication.  But I suppose that's
>> just me ...)
> 
> More than once I've gotten specific questions about whether or not the
> "encapsulated Ethernet frame" inside a TRILL Data frame includes an
> Ethernet FCS just covering the encapsulated material. So I think it is
> better that this sort of thing be mentioned.

Same planet, different universes, I guess.  ;-}

-- 
James Carlson         42.703N 71.076W         <[e-mail]>