Hi there, I have read and learned a lot concerning QoS. What is still unclear to me is the prioritisation mechanism. From what I understood is that there is a schedular servicing the queues. Depending on the switch model IOS, XE-OS, NX-OS there is a different algorithm running. Like DWRR, or WFQ, ... What I don't understand is how do you tell which queue should be served first. Normally you classify the interesting traffic, mark it with CoS, DSCP or qos-group, ... In the policy you assign a given bandwidth per queue. But how do you say this queue needs to be served before other queues? In most switches you have a maximum of 8 queues, so why should you have like 56possibilities with DSCP if you can only map it to 8queueus? Same with qos-groups you have more than 100 posibilities but how do you match these possibilities with your queues? Thanks for the clarification. David ... View more