Greg,

You seem to be confusing and mixing things up.

Please see inline.

> On Apr 12, 2019, at 2:50 AM, Greg Mirsky <[email protected]> wrote:
> 
> Dear Editors, et al.,
> I've read the latest -07 version and would like to share my comments and 
> questions with you:
>       • in the earlier version of the draft, the O-bit was introduced and 
> defined as:
> OAM Flag Bit (O bit):  The O bit is set to indicate that the packet is an OAM 
> packet.
> At the same time, in the latest version, the new Next Protocol value (0x81) 
> to identify iOAM Data was introduced. Hence are my questions:
>       • What must be the value of the O-bit when the value of the Next 
> Protocol field is iOAM?

The O bit “is set to indicate that the packet is an OAM packet”.
IAOM is not an OAM packet. Hence, O bit clear if VXLAN-GPE encapsulates a 
non-OAM packet and adds an IOAM shim.

>       • Do you plan to define the Next Protocol values for active OAM 
> protocols, e.g., Echo Request/Reply, BFD, Performance Monitoring?

I cannot speak to “plans” (replying as “et al.”, not as “editor”), but I expect 
OAM documents ought to have those requested, and you do not need necessarily 
all of those — the nex protocol IPv4 / IPv6 can encapsulate ICMP, UDP/BFD, 
etc., etc., etc., etc.

>       • How to interpret the situation when the O-bit value is 1 but the 
> value of the Next Protocol field is, for example, NSH, i.e.., not any of OAM 
> protocols?

I expect it means there’s OAM within that NSH (sometimes there’s no such things 
as “OAM Protocols”), or an unhandled OAM protocol.

>       • I believe that the use of the dedicated OAM flag and the Next 
> Protocol field for a fixed-size header that cannot include meta-data is 
> unwarranted and adds unnecessary complexity.

Disagree. 

See example where protocol is IP carrying an OAM packet.

> I suggest not to use O-bit in the VXLAN-GPE header and release it into the 
> Reserved field.  I don't see the apparent benefit of using the flag, as the 
> VXLA-GPE uses the fixed size header and the header cannot carry OAM data in 
> it. The only role the VXLAN-GPE header must perform, in my opinion, is to 
> unambiguously identify the payload type that immediately follows the header 
> as OAM (demultiplexing OAM protocols may be done in OAM Header shim).
> Much appreciate your consideration.
> 

Best,

—
Carlos Pignataro, [email protected]

“Sometimes I use big words that I do not fully understand, to make myself sound 
more photosynthesis."

> Regards,
> Greg
> _______________________________________________
> nvo3 mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/nvo3

_______________________________________________
nvo3 mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/nvo3

Reply via email to