Re: [ippm] Quick comment on draft-ietf-ippm-ioam-data-11

[[e-mail]]

Hi Frank and Shwetha,

Thank you for the clear explanation.
Considering the IOAM-Data draft is the IOAM base document referenced by many other drafts, it would be nice if you can add some text to explain it, otherwise I suspect that the question shall be brought up again sometime.

Best Regards,
Xiao Min









原始邮件



发件人：FrankBrockners(fbrockne)
收件人：肖敏10093570;[e-mail];
抄送人：[e-mail];
日 期 ：2021年01月07日 01:14
主 题 ：RE: [ippm] Quick comment on draft-ietf-ippm-ioam-data-11






Hi Xiao Min,


 


the 7-bit wide registry for IOAM-Option-Types is because some protocols, like e.g. Geneve, only offer room for 7 bits.
 See https://tools.ietf.org/html/draft-brockners-ippm-ioam-geneve-05#section-3
 “   Type:  8-bit field defining the IOAM Option type, as defined in


      Section 7.2 of [I-D.ietf-ippm-ioam-data].  The 'C' bit MUST be set


      to zero.”


 


This requirement drove the change from 8 to 7 bits – back in March 2018, see:


https://github.com/inband-oam/ietf/commit/22b33b12863fa62dd80d47a00b859bce82b69e60
 “IOAM-Type code point reduced from 256 -> 128 to handle encaps like Geneve where top bit in type reserved.”


(Thanks to Shwetha for digging up the reference).


 


Cheers, Frank


 




From: ippm <[e-mail]> On Behalf Of [e-mail]
 Sent: Dienstag, 5. Januar 2021 03:34
 To: [e-mail]
 Subject: [ippm] Quick comment on draft-ietf-ippm-ioam-data-11




 

Hi authors,
 
 While updating "IOAM over BIER" draft, I noticed that in Section 8.1 of IOAM-Data draft 128 code points are defined for IOAM Option-Type Registry, nevertheless in whether draft-ietf-ippm-ioam-ipv6-options or draft-ietf-sfc-ioam-nsh, IOAM Type is an 8-bit field, could 256 code points instead of 128 code points be defined?
 
 Best Regards,
 Xiao Min