QOS or more bandwidth

Ukyo Kuonji kawaii_iinazuke at hotmail.com
Tue May 29 13:54:32 UTC 2001

The problem is, while most vendors support tagging and priority queuing, non 
of the current vendors can support true end to end QoS.  Instead, we have 
taken to calling their options CoS.

The problem that I have seen is that while you can make certain that a good 
effort is made to ensure that your high proirity traffic is transmitted 
before your best effort traffic, you have no real way to ensure that the 
high priority arrives at the destination in the same manner that it was 
transmitted.  I'm talking about packet order, jitter, and latency.  Sure, it 
will probably get there, but will the data still be worth anything.

For Internet traffic, QoS/CoS is probably not worth it, as there is no way 
to realistically do either across two or more network providers.  The real 
need will be on single provider wishing to sell more than just Internet 
across their expensive backbone.  Such applications will be Toll-quality 
voice, production/broadcast-quality video, VPN, etc.

The way I have seen it, either IP QoS will have to become a reality, or the 
applications themselves will need to change to handle the poor CoS 
substitute that is offered now.


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---  Original Message  ---

Most competitive vendors now provide native and upgrade provisions for QoS 
in one form or another. The problems most often encountered revolve around 
multi-vendor cos/qos feature implementation incompatibilities. The "least 
common denominator features" that are needed for basic interworking usually 
do not extend to 'differentiating' features that vendors like to hold close 
to the vest, such as prioritization and cos/qos features. Not without much 
grief, in any event. It forces one to seriously consider single vendor 
solutions. fwiw.

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