[j-nsp] Use cases for IntServ in MPLS backbones

[James Bensley]

On Tue, 2 Oct 2018 at 10:57, Mark Tinka <mark.tinka at seacom.mu> wrote:
> I've never quite understood it when customers ask for 8 or even 16 classes. When it comes down to it, I've not been able to distill the queues to more than 3. Simply put, High, Medium and Low. The 4th queue is for the network itself.

I'm not saying I agree with this 8 classes - just stating what it was
:) I also agree that most people genuinely don't need more than 3-4.
We often "helped" (nudged) customers to design their traffic into just
a few classes.

Here in the land of Her Majesty and cups of tea, if you want to
operate as part of the Public Services Network (a national effort to
provide unified services to the public sector across multiple
providers to stamp out any monopoly) you must comply with their 6
class model [1]:
https://www.gov.uk/government/publications/psn-quality-of-service-qos-specification/psn-quality-of-service-qos-specification

So this 6 classes, we split voice signalling and media into two, with
the media being an LLQ, and had a separate class to guarantee traffic
for control and MGMT plane traffic (e.g. we can still SSH to our
routers with a customer DoS is filling the pipes) we ended up with 8.
Yay :(

Cheers,
James.

[1] As is customary with any tech savvy government, they've since
sacked off various PSN standards without providing any replacement so
everyone is just sticking to the same expired standards for now
<facepalm.gif>