DSCP to CoS mapping

[RaphaelL]

Hi ,

I'm just curious , what do you guys have configured in your MS QoS settings for the DSCP to CoS mapping ?

Default or a long list of mappings ?

[jimmyt234]

99.9% of the time we are simply enabling 'Trust incoming DSCP' and that's it.

[RaphaelL]

What about your DSCP to Cos mapping list

[jimmyt234]

Never changed it...

[RWelch]

Interesting question and one not well articulated in the documentation (shocker).

The MS Switch Quality of Service Defined documentation appears to be the "default" dashboard settings for all MS devices in the dashboard.

But when looking for the practical application scenarios, such as the Hybrid Campus LAN Design Guide (CVD) however the authors adjusted the DSCP to Class-of-Service queue mappings as follows:  

I currently run the top (default) mapping but have tinkered with the Hybrid Campus LAN mappings.  

[KarstenI]

To my understanding, the traffic is now just spread among 5 queues instead of 4 as in the default. In default AF41 and EF end up in one queue with the highest relative priority, while the other model places AF21 and AF31 in the same queue and separates EF even further. Looks even better.

[RaphaelL]

And from what I do understand anything not included in the mapping will go into the default queue. 

CS1,CS3,CS5 would be an example.

[pdeleuw]

I try to avoid the term priority when talking about Meraki and QoS. There are not any priority queues. It is a bandwidth management, no prioritization.

[KarstenI]

Oh, yes. If someone is used to terms like priority queueing, then it may not be very clear. I tried to explain that higher queues have a higher weight than lower queues. But I would still say that a queue that is served with a higher weight is still prioritized over the other queue. 

[KarstenI]

I also keep them default when possible. But I make sure that all the different flows end up in the right queue based on the DSCP.

And always remember: QoS is for poor people who can't afford bandwidth. 😂

[PhilipDAth]

Default on every customer.

[Brash]

Default everywhere.

A bit over 'over-spec', good design and getting rid of traditional VOIP goes a long way to making everyone's life just a little easier 😆