Subject: RE: CLS

From: "Naidu, Venkata" <[email-masked]>
Date: Tue, 16 Oct 2001 10:44:28 -0400

Hemant:

  Apart from what Eric has pointed out, there has been
  an extensive work done (in the past) to map service 
  classes between Internet and ATM technologies

  As per RFC2381 recommendations:
     Guaranteed Service    ->     CBR or rtVBR
     Controlled Load       ->     nrtVBR or ABR (with a minimum
                                  cell rate)
     Best Effort           ->     UBR or ABR

  But in my opinion ABR is the odd man out. You can't
  directly map ABR to either "Controlled Load" or "Best effort".
  There has been some research in ALS (Adaptive Load Service)
  which is an ABR-Like Service for the Internet.

     http://citeseer.nj.nec.com/271051.html

--Venkata Naidu

-> Hemant,
-> 
->     ABR is ATM specific, and somewhat more analogous to Guaranteed
-> Service rather than Controlled Load Service.  GS and CLS are 
-> Integrated
-> Services based - which means they (in theory at least) are 
-> supported by
-> more generalized IP forwarding devices (potentially including ATM).
-> 
-> You wrote:
-> 
-> > Hi !
-> > I need to ask few basic doubts.
-> >
-> > 1. How is Controlled load service (CLS) different from ABR ?
-> > 2. Which are the user applications of CLS ?
-> > 3. If CLS provides approximately the same QoS under heavy 
-> loads as under
-> > light loads,why isn't it referred in guaranteed service category ?
-> > 4. How does MPLS implement CLS ?
-> >
-> > Regards,
-> > Hemant
->