What is the difference between cos and dscp

Most enterprise switches will. Speaking specifically of Cisco, which I'm most familiar with, you can configure the command " mls qos trust dscp " and that will honor the dscp value. Todd this is if the switch has no layer 3 functionality and no routing is happening on it? Ron, it really depends upon your configuration and hardware. It's much more common these days for lower cost switches to support DSCP in some automated fashion, with little or no configuration required.

If you're trunking switches it may not transport the DSCP values over trunks without some additional configuration.

Just be aware of these possibilities. I've been surprised at how "automatic" it is these days but still find new switches needing a bit of fine tuning occasionally. The difference between The trunk needs to use the If the It is called Layer 2 packet header:.

The tpid field indicates that the message is an The tci field has 3 bits for marking priority. If the priority is marked, it is called an The length of the type of sevice field of the ip packet header is 1 byte, and the upper 3 bits are used to mark the priority, so there are 8 ip preference levels from The middle 4bit of the type of service field is the tos subfield, and the lowest 1bit is unused but must be set to 0.

As you know there are 3 values you can trust. IPP is 3 bit value for layer 3 QoS marking and have less flexibility 8 different values only. If switch is layer 2 not capable of viewing IP header information option is to trust CoS. Again this depend on your choice what would you like to trust when packets get entered to your network.

First, we will see how things works when packets going from wireless client to wired client. But when WLC send packet to wired client, depending on the trust model this behavior is vary. Which is really great as you will preserve original DSCP value set by the wireless client.

Now we will see what happen to the return traffic wired to wireless. Which is great as no rewrite of DSCP. If you trust DSCP original values preserved. Understanding Wireless QoS — Part 1 2. Understanding Wireless QoS — Part 2 3. How quickly will I get my solution? We can't guarantee quick solutions - Experts Exchange isn't a help desk. We're a community of IT professionals committed to sharing knowledge. Our experts volunteer their time to help other people in the technology industry learn and succeed.

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