RE: Dropping the Local Overbooking Multiplier (LOM) method from DS-TE specs?

["Choudhury, Sanjaya" <Sanjaya.Choudhury@marconi.com>]

Hi! DSTE-REQ already states that the per-CT overbooking
is an optional feature and does not require the vendors
to implement it.

We already discussed the overbooking/underbooking issues
quite some time back. I don't think we, should change
requirement [DSTE-REQ] at this stage (past last call),
unless there is a real problem or limitation.

If we are trying to change the requirement because the 
LOM concept is difficult, let's take steps to clarify
the concept by necessary editorial changes (and examples).

Thanks,
sanjay

> -----Original Message-----
> From: Francois Le Faucheur (flefauch) [mailto:flefauch@cisco.com]
> Sent: Monday, May 26, 2003 9:05 AM
> To: te-wg@ops.ietf.org
> Subject: RE: Dropping the Local Overbooking Multiplier (LOM) 
> method from
> DS-TE specs?
> 
> 
> All TEWGers,
> 
> Thoughts on dropping/keeping LOM in base DS-TE specs?
> 
> Thanks
> 
> Francois
> 
> >> -----Original Message-----
> >> From: Francois Le Faucheur (flefauch) 
> >> Sent: 26 May 2003 14:59
> >> To: Kireeti Kompella; te-wg@ops.ietf.org
> >> Subject: Dropping the Local Overbooking Multiplier (LOM) 
> >> method from DS-TE specs?
> >> 
> >> 
> >> Kireeti,
> >> 
> >> Once upon a time, we merged 3 technical proposals for DS-TE (one of
> >> which was yours) into a common one. One of the 
> capabilities that was
> >> unique to your proposal was the ability to support 
> overbooking ratios
> >> which are different on a per CT AND per link basis (while the other
> >> methods supported different ratios on different links and different
> >> ratios on a per CT basis, not not on a per CT and per-link 
> >> basis). Back
> >> then you made a argument that there was some value in 
> allowing this.
> >> This resulted in the addition of the optional Local Overbooking
> >> Multiplier (LOM) method in the DS-TE specs.
> >> 
> >> A number of people commented that considering the ratio of 
> >> complexity vs
> >> functionality for this particular capability, we may be better off
> >> issueing the base DS-TE specs without this for now and 
> then add this
> >> capability later or in a separate document. I personnally 
> also favors
> >> such an approach.
> >> 
> >> What is your take on this?
> >> 
> >> Cheers
> >> 
> >> Francois
> >> 
> >> >> -----Original Message-----
> >> >> From: Jim Boyle [mailto:jboyle@pdnets.com] 
> >> >> Sent: 24 May 2003 02:31
> >> >> To: Francois Le Faucheur (flefauch)
> >> >> Cc: te-wg@ops.ietf.org; Lai, Wai S , ALABS
> >> >> Subject: RE: Reflecting new-MAM/SAM definition in 
> diff-te drafts 
> >> >> 
> >> >> 
> >> <clip>
> >> >> 
> >> >> btw... I also think LOMs are lots of complexity for 
> little gain :)
> >> >> 
> >> >> 
> >> >> 
> >> >> On Tue, 20 May 2003, Francois Le Faucheur (flefauch) wrote:
> >> >> 
> >> >> > Jerry,
> >> >> > 
> >> >> > >> -----Original Message-----
> >> >> > >> From: Ash, Gerald R (Jerry), ALABS [mailto:gash@att.com] 
> >> >> > >> Sent: 20 May 2003 17:35
> >> >> > >> To: Dimitry Haskin; Francois Le Faucheur (flefauch)
> >> >> > >> Cc: Ash, Gerald R (Jerry), ALABS; te-wg@ops.ietf.org; Lai, 
> >> >> > >> Wai S (Waisum), ALABS
> >> >> > >> Subject: RE: Reflecting new-MAM/SAM definition in 
> >> diff-te drafts
> >> >> > >> 
> >> >> > >> 
> >> >> > >> Dimitry, Francois,
> >> >> > >> 
> >> >> > >> > >     o SUM (Reserved (CTc)) <= Max Reservable 
> Bandwidth, 
> >> >> > >> > >         for all "c" in the range 0 <= c <= (MaxCT-1)
> >> >> > >> > > 
> >> >> > >> > > However, this formula is incorrect for DS-TE 
> when per-CT 
> >> >> > >> > > LOM's are used, since the above formula only 
> >> >> reflects the Max 
> >> >> > >> > > Reservable Bandwidth for the entire link, and does not 
> >> >> > >> > > reflect the per-CT local overbooking factors.  So what 
> >> >> > >> > > formula do you suggest when per-CT LOM's are used?
> >> >> > >> 
> >> >> > >> > Wouldn't 'Reserved (CTc)' it the above formula already 
> >> >> > >> accounts for the
> >> >> > >> > overbooking multiplier at CTc?  I don't see how this 
> >> >> > >> formula precludes
> >> >> > >> > per-CT LOM's to be used. Please explain.
> >> >> > >> 
> >> >> > >> Are you then proposing these formulas:
> >> >> > >> 
> >> >> > >> 1. When per-CT LOMs are not used:
> >> >> > >> 
> >> >> > >>      o SUM (Reserved(CTc)) <= Max Reservable Bandwidth, 
> >> >> > >>          for all "c" in the range 0 <= c <= (MaxCT-1)
> >> >> > >> 
> >> >> > >> 2. When per-CT LOMs are used:
> >> >> > >> 
> >> >> > >>      o SUM (Normalized(CTc)) <= Max Reservable Bandwidth, 
> >> >> > >>          for all "c" in the range 0 <= c <= (MaxCT-1)
> >> >> > >> 
> >> >> > >> Is that correct?  Please confirm, and/or give the formulas 
> >> >> > >> you propose.
> >> >> > 
> >> >> > Yes, this is exactly what I propose.
> >> >> > I think this is similar to what you were proposing, only 
> >> >> using "Max Res
> >> >> > Bw" instead of "Max Link Bw". 
> >> >> > 
> >> >> > Sorry I didn't make that very clear before.
> >> >> > 
> >> >> > Cheers
> >> >> > 
> >> >> > FRancois
> >> >> > 
> >> >> > >> 
> >> >> > >> Thanks,
> >> >> > >> Jerry
> >> >> > >> 
> >> >> > 
> >> >> > 
> >> >> > 
> >> >> > 
> >> >> 
> >> >> 
> >> 
> >> 
>