I write the following istruction: #Attach CBQ to the root of the output device tc qdisc add dev eth0 root handle 1: cbq bandwidth 10Mbit cell 8 avpkt 1000 mpu 64 #Class for the real-time traffic. Avpkt here doesn't have the default value of 1000 because #realtime multimedia traffic is usually characterized by small packets \ tc class add dev eth0 parent 1:0 classid 1:1 cbq \ bandwidth 10Mbit rate 1Mbit avpkt 400 prio 1 bounded isolated \ allot 1514 weight 1 maxburst 2 #aggiungo il filtro guardando esempio howto Advanced Routing(2.4) pag 22 tc filter add dev eth0 parent 1:0 protocol ip prio 100 u32 match ip dst 192.168.1.2/32 flowid 1:1 Now i don't manage to del the filter.Someone can write me the command please. I wrote this istruction in the way that they were similar with the sample in the Avanced Howto 2.4. I don't understand why it's different from the way that someone can understand from the help of tc!! Thanks (and sorry for my english :-))