Hi, In the GRED queueing discipline of linux traffic control, we can define around 16 Virtual Queues with different RED parameters for each one of these. As far as I think, while applying RED on each of the virtual queues, with the grio option set, quave(the average queue length) of a virtual queue with priority= n is given by the sum of the virtual queues with priority greater than n ... I have the following questions : 1. Is my understanding correct ? 2. What if I set the priority of two virtual queues as equal ? 3. If I want that the Average queue length being used before dropping a packet should be equal to the sum of the average queue length of all the virtual queues, where would i have to make changes in the source code ... ie, just making changes in sch_gred.c would suffice or I have to make changes to some other files also ... Rahul -- Rahul Hari Senior Under Grad. Student, Department of CSE, ITBHU, Varanasi. Ph: +91-9845347020