Subject: Quantitative PHBs

From: Shahram Davari <[email-masked]>
Date: Fri, 1 Oct 1999 10:44:47 -0700

Hi All,

I wanted to know, whether it is possible to define a quantitative PHB. For
example can a PHB be defined that guarantees a quantitative delay bound or a
quantitative loss ratio per hop. And is there a reason that so far only
qualitative PHBs have been defined?

Thanks,
                            _\\|//_
                            ( O-O )
   ~~~~~~~~~~~~~~~~~~~~~~o00~~(_)~~00o~~~~~~~~~~~~~~~~~~~~~~~~
          Shahram Davari
          Systems Engineer, Product Research
          PMC-Sierra Inc. 
          105-8555 Baxter Place
          Burnaby, BC V5A 4V7, Canada
          Phone: +1 (604) 415-6000, Ext. 2428
                         oooO
   ~~~~~~~~~~~~~~~~~~~~~~(   )~~ Oooo~~~~~~~~~~~~~~~~~~~~~~~~~
                          \ (    (   )
                           \_)    ) /
                                 (_/

---

From: Zoltan Richard Turanyi <[email-masked]>
Date: Mon, 04 Oct 1999 10:13:27 +0200

Shahram,

I do not think that a PHB can be quantitative in itself. 
No per hop mechanism can guarantee a certain (low) loss 
ratio when significantly more traffic arrives that can 
be served. Rather, a combination of per hop mechanisms and
traffic engineering (or admission control) can result in 
quantitative QoS. My understanding is that at present the 
first is standardised to some extent as PHBs, while the 
second is left to the operators.

Zoltan

--------------------------------------------
Zoltan Richard Turanyi  
Research Fellow, Ericsson Hungary
Traffic Ananysis and Network Performance Lab
Phone: +36-1-437-7636

---

From: Brian E Carpenter <[email-masked]>
Date: Mon, 04 Oct 1999 10:24:40 -0500

Zoltan,

In general that's true. EF is supposed to be an exception, but
it does depend on 100% provisioning and admission control.

  Brian

---

From: Zoltan Richard Turanyi <[email-masked]>
Date: Mon, 04 Oct 1999 17:50:59 +0200

> it does depend on 100% provisioning and admission control.
In that case it is no exception, is it?

Zoltan