Re: [nvo3] NVO3 WG Adoption of draft-quinn-vxlan-gpe-04

["Larry Kreeger (kreeger)" <[e-mail]>]

Regarding Joe Touch's comment about explicitly NOT indicating IPv4 vs IPv6
in the Next Protocol (only indicating IP), I don't see what the advantages
of doing this are.  It seems more philosophical.

By indicating IPv4/IPv6 in the next protocol, it allows implementations to
only make one decision before parsing the IP header.  By doing two steps
NP->IP->IPv4/v6, it adds one more parsing step to the implementation, for
no gain that I can think of.

As Diego pointed out earlier, there is already a precedent in Ethernet for
indicating the IP version in the next protocol from the layer below it.

 - Larry

On 4/29/15 11:36 AM, "Behcet Sarikaya" <[e-mail]> wrote:

>On Wed, Apr 29, 2015 at 1:13 PM, Paul Quinn (paulq) <[e-mail]>
>wrote:
>>
>>> On Apr 29, 2015, at 12:01 PM, Behcet Sarikaya <[e-mail]>
>>>wrote:
>>>
>>> On Tue, Apr 28, 2015 at 5:03 PM, Behcet Sarikaya
>>><[e-mail]> wrote:
>>>> Hi Benson,
>>>>
>>>> Joe Touch wrote this on intarea list:
>>>>
>>>> There is no reason for having the GUE header differentiate between
>>>> payload=IPv4 and payload=IPv6. The IP version is addressed by the
>>>> version field of the IP header. If GUE encapsulates both type of IP
>>>>the
>>>> same way (and it should), it should NOT differentiate between them in
>>>> its (GUE) header.
>>>>
>>>>
>>>> I think the same applies to gpe header.
>>>>
>>>> Plus the issues on the "NSH" protocol.
>>>
>>> Curiously if you look at the nsh draft, Section 3.2,
>>>
>>> NSH Base Header
>>>
>>> also has a next protocol field with the same encoding.
>>>
>>> Anybody understands what is going on?
>>
>> Yes, the concept is that you don't know what you want to carry via GPE.
>> Today it might be v4, v6, ethernet, NSH or something else.  Tomorrow,
>>who knows?  But more importantly, we need to enable that stacking to
>>occur.
>>
>
>
>Please convince not me but Joe Touch on v4 and v6 thing.
>
>> The format of NSH is orthogonal -- as is the format of Ethernet for
>>that matter.  From an outer header (i.e. VXLAN-GPE or other) you need to
>>be able to identify the inner protocol.
>>
>
>Are we talking about VM-to-VM communication? I think that is what
>VXLAN was designed for.
>
>Regards,
>
>Behcet
>> Paul
>>