How are queues serviced in Cisco IOS routers with the CBWFQ algorithm? 

Answer options:

A. first-in, first-out
B. weighted round robin based on assigned bandwidth
C. strict priority based on assigned priority
D. last-in, first-out
E. weighted round robin based on assigned priority

B

Class Based Weighted Fair queuing is an advanced form of WFQ that supports user defined traffic classes i.e. one can define traffic classes based on match criteria like protocols, access control lists (ACLs), and input interfaces. A flow satisfying the match criteria for a class contributes the traffic for that particular defined class. A queue is allocated for each class, and the traffic belonging to that class is directed to the queue for that class.