Cell Relay Archive

["ronald h. davis" <ronaldd@lucent.com>]

albert.e.manfredi@boeing.com wrote:
> 
> In article <35446F67.2B7453E@intec.rug.ac.be>,
>   Mike Vogeleer <Mike.Vogeleer@intec.rug.ac.be> wrote:
> >
> > Hi,
> >
> > Can anyone explain me (in general + some simple examples) the difference
> > between QoS and CoS (class of service). Is the term 'CoS' ever really
> > used?
> 
> Class of service refers to CBR, VBR-rt, VBR-nrt, ABR, UBR. Whereas QoS is the
> more detailed requirement within each class, such as PCR, MCR, SCR, MBS, and
> so on, 
>

bert,

you're right in your explanation, but i'll just make a small nit about your
defintion of qos.  qos is based upon the following parameters:

	cell tranfer delay
	cell delay variation
	cell loss ratio
	cell error ratio
	severely error cell block ratio
	cell misinsertion ratio

pcr, mcr, &c. are parts of the traffic contract which are used to determine
if incoming traffic is compliant (and therefore worthy of qos guarantees).

-- 
  __  ______  __  / __/ | 	lucent technologies, naperville il, usa
_/ (_(_) / (_(_/_/_(_/  . 	ronald.h.davis@lucent.com
for there are many great deeds done in the small struggles of life.
life, misfortune, isolation, abandonment, poverty, are battlefields
which have their heros; obscure heroes, sometimes greater than the
illustrious heros.
				-victor hugo