RE: Flow label and its uses

["Bora Akyol" <bora@broadcom.com>]

From a switching hardware perspective, it would be nice
to either define the use of this field as --endpoint only--
or label it "Reserved."

There has been significant time since RFC3697 and the lack
of applications may indicate that this field (with
the exception of NIMROD) may not have a use at all.

Regards

Bora


> -----Original Message-----
> From: Brian E Carpenter [mailto:brc@zurich.ibm.com] 
> Sent: Wednesday, January 18, 2006 5:03 AM
> To: Fred Baker
> Cc: Bora Akyol; v6ops@ops.ietf.org
> Subject: Re: Flow label and its uses
> 
> Fred Baker wrote:
> > personally, I would label it reserved. I think the authors of RFC  
> > 3697 see it as something akin to a 20 bit DSCP, and if 
> someone wants  
> > to see it that way it's fine by me. In any event, that is 
> an ipv6wg  
> > question more than a v6ops question.
> 
> Indeed. And it isn't "reserved"; it *is* part of the header 
> with the semantics defined to the extent of RFC 3697. My 
> point is that people who want to use it, e.g. for load 
> balancing, ought to be writing drafts.
> 
>     Brian
> 
> > 
> > On Jan 17, 2006, at 3:50 PM, Bora Akyol wrote:
> > 
> >> A pointer to some reference material on NIMROD:
> >>
> >> http://ana-3.lcs.mit.edu/~jnc/nimrod/nimsl.html
> >>
> >> http://ana-3.lcs.mit.edu/~jnc/nimrod/docs.html
> >>
> >> http://www.ir.bbn.com/projects/nimrod
> >>
> >> Is there any use in keeping flow label as is, or should be 
> relabeled 
> >> as "Reserved"?
> >>
> >> I think there is some agreement that
> >> the label in
> >> (Label, IP Source Address, IP Destination Address) triplet 
> does not 
> >> add a whole lot of value.
> >>
> >> Regards,
> >>
> >> Bora
> >>
> >>
> >>> -----Original Message-----
> >>> From: Fred Baker [mailto:fred@cisco.com]
> >>> Sent: Tuesday, January 17, 2006 3:33 PM
> >>> To: Bora Akyol
> >>> Cc: Vishwas Manral; v6ops@ops.ietf.org
> >>> Subject: Re: Flow label and its uses
> >>>
> >>> I'd encourage you to look at the big-internet archives (if they
> >>> exist) from about 1993. The flow label was proposed to 
> support the 
> >>> nimrod architecture, and in essence *was* what we later 
> described as 
> >>> "MPLS", but in the IPv6 header. That's one of the reasons 
> that the 
> >>> flow label isn't covered by the IPSEC checksum - so it could be 
> >>> managed appropriately at ingress and egress to the 
> various "flows" 
> >>> or "LSPs".
> >>>
> >>> Yes, there has been a lot of water under that bridge. Between 
> >>> requiring the flow label to pass unchanged and making the address 
> >>> fixed length and of the same construction as the IPv4 address, 
> >>> Nimrod became very difficult to implement in IPv6, and Noel still 
> >>> isn't very happy with the IPv6 community.
> >>>
> >>> On Jan 17, 2006, at 3:11 PM, Bora Akyol wrote:
> >>>
> >>>>
> >>>>
> >>>>> -----Original Message-----
> >>>>> From: Vishwas Manral [mailto:Vishwas@sinett.com]
> >>>>
> >>>>
> >>>>> And a more recent draft
> >>>>> http://www.faqs.org/ftp/pub/internet-drafts/draft-chakravorty-
> >>>>> bcc-flowla
> >>>>> bel-00.txt
> >>>>
> >>>>
> >>>> This last one looks a lot like MPLS in IPv6 ;-)
> >>>>
> >>>> Bora
> >>>
> >>>
> >>>
> > 
> 
> 
>