Re: IP Layer 2 Transport over L2TPv3

Hi Carlos,

Please see in-line.

Carlos Pignataro wrote:
> Hi Prasad,
> 
> Please see inline.
> 
> Circa 9/20/2005 7:01 AM, Prasad Yadati said the following:
> 
>>Carlos,
>>
>>Please see in-line.
>>
>>Carlos Pignataro wrote:
>>
>>
>>>Prasad,
>>>
>>>Thanks. Please see a couple of comments inline.
>>>
>>>List,
>>>
>>>Any further comments on the request to accept this draft as a working
>>>group document?
>>>
>>>
>>>Circa 9/17/2005 5:50 AM, Prasad Yadati said the following:
>>>
>>>
>>>>Good one Carlos.
>>>>How about just specifying it as "IP transport over L2TPv3".
>>>>
>>>
>>>
>>>Thanks.
>>>
>>>The "IP Layer 2" was added there for 2 reasons:
>>>1. To somehow differentiate raw-IP from framed-IP being transported over
>>>   L2TPv3 while trying to reference the NSP function that interfaces the
>>>   L2 AC with the IP PW Termination.
>>>2. Symmetry/parity name with the already defined PW Type for MPLS PWE3.
>>>
>>
>>But as per this draft, no "IP layer 2" information is transported.
> 
> 
> Yes, only IP datagrams are transported, although there is a Layer 2
> attachment circuit, and hence "IP Layer 2". The NSP function "extracts

Attachment circuit layer 2 is already terminated. Isn't it ? L2TPv3 in this case 
does not aware of attachment circuit's layer 2. In fact it does not matter what 
kind of layer 2 IP was carried at the attachment circuit.
I am sorry Corlos, I am still not clear.

> IP datagrams from the Layer 2 frames" and that's the motivation for the
> name, make a distinction from framed-IP. See below as well.
> 
> 
>>Rather we are trying to prevent the same. For me, "IP layer 2" seems to
>>be mis-leading.
>>
>>
>>
>>>"IP transport" may possibly be too generic for the procedures defined.
>>
>>
>>Corlos, for me, "IP transport" seems more appropriate than current. In
>>this case as far as L2TPv3 is concerned, it is transporting IP rather
>>than layer 2 frame.
> 
> 
> IMHO, "IP transport" is too generic, and does not fully convey what's
> happening in the interface between the physical layer 2 interface and
> the pseudowire termination. Other PW Types transport IP (framed-IP) as
> well. I thought about "raw ip" and "native ip" but opted against them
> for a similar reason. Any other suggestions?

How about "Abstracted/Extracted IP over L2TPv3" ?
If this draft can be, really generic, I mean if it  can be used even for non-pw 
cases where L2TPv3 carries generic IP datagrams, we may have "IP transport over 
L2TPv3" ?

Kind Regards
Prasad



> 
> 
>>>
>>>>Wondering whether we can have a generic "Layer 3 transport over L2TPv3"
>>>>and specify transport of all layer 3 protocols (IP, IPX,....) in it
>>>>including IP.
>>>
>>>
>>>
>>>Do you mean multiple L3 protocols at the same time over the session? I'd
>>>think we can use existing L2 transports to accomplish that. OTOH, IP as
>>>L3 stands out in the applications of an "IP L2" session.
>>
>>Sorry I was not clear. I meant to combine specification of other layer 3
>>data packets over L2TPv3 in one draft. May be that is not needed. We may
>>have separate similar such of these drafts for other layer 3 protocols.
>>Please ignore this comment.
> 
> 
> OK. Thanks,
> 
> --Carlos.
> 
> 
>>Thanks
>>Prasad
>>
>>
>>>Thanks !
>>>
>>>--Carlos.
>>>
>>>
>>>
>>>>Regards
>>>>Prasad
>>>>
>>>>Carlos Pignataro wrote:
>>>>
>>>>
>>>>
>>>>>Hi All,
>>>>>
>>>>>We submitted the following `IP Layer 2 Transport over L2TPv3' draft:
>>>>>http://www1.ietf.org/mail-archive/web/i-d-announce/current/msg06623.html
>>>>>
>>>>>that details the tunneling of IP datagrams directly over an L2TPv3
>>>>>session, and defines the `CE IP Address AVP' as well.
>>>>>
>>>>>We would like it to become an l2tpext working group document, and seek
>>>>>review, feedback and comments from the WG.
>>>>>So we ask here for the draft to be accepted as work item for the group.
>>>>>Your feedback will be most appreciated.
>>>>>
>>>>>Thanks,
>>>>>
>>>>
>