Re: [RPRWG] Fairness Ad-Hoc Reminder

["Jon Schuringa" <jon.schuringa@xxxxxxxxxxxx>]

All,

Based on the latest discussions about shaperD and fairness , I believe
the basic question is: Can STQ's fill when unreservedRate < lineRate ?

If yes: we can have classA0 blockage (as DVJ pointed out), but fairness
works
If no: fairness doesn't work (see Wang Chao's mail), but classA0 works

Shaper D controls the amount of A1, B and C traffic to be added on the ring.
STQ traffic is not shaped by shaper D, but STQ traffic decrements shaper D's
credits. So, if there is a lot of traffic in the STQ, then this, together
with add
traffic, will consume all the credits and add traffic will be blocked. Add
traffic
remains blocked as long as the STQ is drained at lineRate.
Can the STQ depth grow in the first place? I think not.

For correct operation the STQ depth must be able to grow. But then
we run into classA0 problems in single transit queue stations, because
STQ traffic can produce an unshaped continues traffic stream at line rate.
These and other problems would be fixed by shaping STQ traffic.


A typo in DVJ's cls09_fairness, page 211, line 45:
 Stations S30-to-S31 simultaneously burst subclassA0+classB traffic at 3% of
link rate
Shouldn't that be:
 Stations S30-to-S60 simultaneously burst subclassA1+classB traffic at 3% of
link rate

Jon


----- Original Message ----- 
From: "David V James" <dvj@xxxxxxxxxxxx>
To: "David V. James" <dvj@xxxxxxxxxxxx>; "Dongmei Wang"
<mei@xxxxxxxxxxxxxxxx>; "John Lemon" <JLemon@xxxxxxxxxxxx>; "Jon Schuringa"
<jon.schuringa@xxxxxxxxxxxx>; "K. K. Ramakrishnan"
<kkrama@xxxxxxxxxxxxxxxx>; "Khaled Amer" <amer@xxxxxxxxxxx>; "Kshitij Kumar"
<kkumar@xxxxxxxxxxxxxx>; "Leon Bruckman" <leonb@xxxxxxxxxxxxx>; "Necdet
Uzun" <nuzun@xxxxxxxxx>; "Robert D Love" <rdlove@xxxxxxxxx>; "Stein
Gjessing" <steing@xxxxxxxxx>; "Yan Robichaud" <yan@xxxxxxxxxxxxxxx>
Cc: "Rpr GroupOf Ieee" <stds-802-17@xxxxxxxx>
Sent: Tuesday, June 24, 2003 1:57 AM
Subject: [RPRWG] Fairness Ad-Hoc Reminder


> All,
>
> A gentle reminder on the Fairness Ad-Hoc:
> In preparation, a document is provided for
> your preview; see attached.
>
> Next meeting:
> Date: Wednesday, June 25, 2003
> Start Time: 10:00:00 AM Pacific Daylight Time
> End Time: 12:55:00 PM Pacific Daylight Time
> Parties: 15
> Dial-in Number: 1-702-835-5000 (Las Vegas, Nevada)
> Participant Access Code: 8021725
>
>
> David V. James
> 3180 South Ct
> Palo Alto, CA 94306
> Home: +1.650.494.0926
>       +1.650.856.9801
> Cell: +1.650.954.6906
> Fax:  +1.360.242.5508
> Base: dvj@xxxxxxxxxxxx