Category Archives: QoS

Class of Service : Classifiers

During my second JNCIE-SEC study and after another unfortunate failure, I stepped back a little bit. Sometimes I need to break for a while to recharge my battery. I am still not sure if I am fully re-charged though but I have to move on. As my little doughter already went to bed, 🙂 I can continue with Class of Service which I think I have never written about before. Feel free to correct my mistakes.

On this post, I will only write about how we can classify a packet and send it to an interface queue which can be a good start for anyone who doesn’t know CoS. You will find a basic setup below and branchK SRX device (which is actually a 12.1X47-D10 firefly VM) will handle the classification of an ICMP packet as an example. The purpose of this post is only about classification. I won’t talk about scheduling etc. Along the road, I will try to talk about more for each of these config items but first I would like to show a working example. Let’s get started.


Only configuration is done under [edit class-of-service] level and nowhere else in this post. Below you also see step by step the function of each config stanza.
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