Re: [sfc] is current SFC architecture supporting different types of SFC header formats?

[Georgios Karagiannis <[e-mail]>]

Hi Carlos, Hi Joel,

Thanks for the clarifications! 

This means that some selection steps for choosing the candidate SFC encapsulation 
have been already taken.

Best regards,
Georgios




> -----Original Message-----
> From: Carlos Pignataro (cpignata) [mailto:[e-mail]]
> Sent: Thursday, December 04, 2014 5:10 PM
> To: Georgios Karagiannis
> Cc: [e-mail]
> Subject: Re: [sfc] is current SFC architecture supporting different types of
> SFC header formats?
> 
> Georgios,
> 
> > On Dec 4, 2014, at 10:33 AM, Georgios Karagiannis
> <[e-mail]> wrote:
> >
> > Hi Carlos,
> >
> > Thank you very much for the clarification!
> >
> >> I see — this is a question for draft-boucadair-sfc-design-analysis
> >> and not for draft-ietf-sfc-architecture. Meaning, it would be up to
> >> the proposed encapsulation to show how they realize the functions of the
> architecture.
> >>
> >> That said, I do not see an “SF Map Index” in the architecture
> >> document, for example.
> >
> > Georgios: Thanks, I see, so additional functions need to be added to the SFC
> architecture if one would like to support the Single Marking Code Point - like
> format.
> >
> 
> No — it’s actually the other way around. The architecture does not retrofit a
> format proposal.
> 
> As Joel said, it’s not just “any” SFC encap proposal. The architecture made
> choices, and encap proposals realize the architecture with different encodings.
> 
> > What about the Explicit Route List. Section 5.6 of the SFC architecture
> draft mentions that "This architecture prescribes additional information being
> added to packets to identify service function paths and often to represent
> metadata.
> > Can such an Explicit Route List being considered as metadata?
> >
> 
> The architecture describes what is necessary in the SFC encapsulation, what is
> metadata, and what the SFC encapsulation is not.
> 
> Thanks,
> 
> Carlos.
> 
> > Best regards,
> > Georgios
> >
> >
> >
> >
> >
> >> -----Original Message-----
> >> From: Carlos Pignataro (cpignata) [mailto:[e-mail]]
> >> Sent: Thursday, December 04, 2014 4:18 PM
> >> To: Georgios Karagiannis
> >> Cc: [e-mail]
> >> Subject: Re: [sfc] is current SFC architecture supporting different
> >> types of SFC header formats?
> >>
> >> Hi Georgios,
> >>
> >> Please see inline.
> >>
> >>> On Dec 4, 2014, at 9:40 AM, Georgios Karagiannis
> >> <[e-mail]> wrote:
> >>>
> >>> Hi Carlos,
> >>>
> >>> Please note that I do not mean to use different SFC encapsulations
> >> simultaneously.
> >>>
> >>
> >> Thanks for the clarification.
> >>
> >>> From what I understood from IETF'91 meeting discussions, the Generic
> >>> SFC
> >> encapsulation technique has not yet been selected by the SFC WG.
> >>>
> >>> I think that this means that the SFC architecture draft cannot be in
> >>> favor for one specific SFC encapsulation technique and at the same
> >>> time
> >> excluding other techniques.
> >>>
> >>
> >> Yes. Again, the SFC architecture document does not concern itself or
> >> take any position on any specifics for any encapsulation format. It
> >> does specify the functions that the SFC encapsulation need to fulfill.
> >>
> >>> My question is:
> >>>
> >>> Can the following two SFC encapsulation techniques be supported by
> >>> the
> >> functions described in the SFC architecture draft?:
> >>>
> >>> o) Single Marking Code Point, like format, see section 5.1 on
> >>> boucadair
> >> draft, see below.
> >>>
> >>> o) Explicit Route List, like format, see section 5.3 on boucadair
> >>> draft, see
> >> below.
> >>>
> >>
> >> I see — this is a question for draft-boucadair-sfc-design-analysis
> >> and not for draft-ietf-sfc-architecture. Meaning, it would be up to
> >> the proposed encapsulation to show how they realize the functions of the
> architecture.
> >>
> >> That said, I do not see an “SF Map Index” in the architecture
> >> document, for example.
> >>
> >> Thanks,
> >>
> >> Carlos.
> >>
> >>> http://www.ietf.org/id/draft-boucadair-sfc-design-analysis-03.txt
> >>>
> >>> Best regards,
> >>> Georgios
> >>>
> >>>
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Carlos Pignataro (cpignata) [mailto:[e-mail]]
> >>>> Sent: Thursday, December 04, 2014 3:02 PM
> >>>> To: Georgios Karagiannis
> >>>> Cc: [e-mail]
> >>>> Subject: Re: [sfc] is current SFC architecture supporting different
> >>>> types of SFC header formats?
> >>>>
> >>>> Hi, Georgios,
> >>>>
> >>>> Do you mean different SFC Encapsulations simultaneously? The SFC
> >>>> charter
> >>>> says:
> >>>>
> >>>> <snip>
> >>>> 3. Generic SFC Encapsulation: This document will describe a single
> >>>> service-level data plane encapsulation format that:
> >>>>
> >>>> </snip>
> >>>>
> >>>> Because interoperability is the goal.
> >>>>
> >>>> Looking at that section, the terminology does not seem to align to
> >>>> the arch and problem-statement documents. Also, that section seems
> >>>> to describe a pseudo-format, not a format. The architecture
> >>>> describes the functions in Section 4.1 and other places.
> >>>>
> >>>> Thanks,
> >>>>
> >>>> Carlos.
> >>>>
> >>>> On 12/4/14, 8:55 AM, "Georgios Karagiannis"
> >>>> <[e-mail]> wrote:
> >>>>
> >>>>> Hi Carlos,
> >>>>>
> >>>>> Thanks for your answer!
> >>>>>
> >>>>> Does this mean that the SFC architecture is allowing the use of
> >>>>> different Service Function Chaining Header (SFC encapsulation) formats?
> >>>>>
> >>>>> I am referring to the different SFC encapsulation formats that are
> >>>>> discussed in section 5 of the following ID:
> >>>>> http://www.ietf.org/id/draft-boucadair-sfc-design-analysis-03.txt
> >>>>>
> >>>>> Best regards,
> >>>>> Georgios
> >>>>>
> >>>>>
> >>>>>> -----Original Message-----
> >>>>>> From: Carlos Pignataro (cpignata) [mailto:[e-mail]]
> >>>>>> Sent: Thursday, December 04, 2014 2:46 PM
> >>>>>> To: Georgios Karagiannis
> >>>>>> Cc: [e-mail]
> >>>>>> Subject: Re: [sfc] is current SFC architecture supporting
> >>>>>> different types of  SFC header formats?
> >>>>>>
> >>>>>> Hi, Georgios,
> >>>>>>
> >>>>>> The SFC architecture document concerns itself with the functions
> >>>>>> and not the  format.
> >>>>>>
> >>>>>> Thanks,
> >>>>>>
> >>>>>> Carlos.
> >>>>>>
> >>>>>>> On Dec 4, 2014, at 5:17 AM, Georgios Karagiannis
> >>>>>> <[e-mail]> wrote:
> >>>>>>>
> >>>>>>> Hi all,
> >>>>>>>
> >>>>>>> Please note that I was reviewing the SFC architecture draft, see
> >>>>>> below, and
> >>>>>> I have a question:
> >>>>>>> http://www.ietf.org/id/draft-ietf-sfc-architecture-02.txt
> >>>>>>>
> >>>>>>>
> >>>>>>> Can you please let me know if the current version of the SFC
> >>>>>>> architecture allows the use of different Service Function
> >>>>>>> Chaining
> >>>>>> Header
> >>>>>> formats?
> >>>>>>>
> >>>>>>> These formats and their analysis can be found in Section 5 of
> >>>>>>> the
> >>>>>> following
> >>>>>> draft:
> >>>>>>>
> >>>>>>> http://www.ietf.org/id/draft-boucadair-sfc-design-analysis-03.tx
> >>>>>>> t
> >>>>>>>
> >>>>>>>
> >>>>>>> If that is not the case, please elaborate why.
> >>>>>>>
> >>>>>>> Best regards,
> >>>>>>> Georgios
> >>>>>>>
> >>>>>>>
> >>>>>>> _______________________________________________
> >>>>>>> sfc mailing list
> >>>>>>> [e-mail]
> >>>>>>> https://www.ietf.org/mailman/listinfo/sfc
> >>>>>
> >>>
> >