4.5 Implement QoS Services 350-501 Practice Questions (Page 2)

Questions 6–10

1. 6application · medium

   A service provider is connecting a customer site to the network via a 10 Mbps access link. The customer's traffic is bursty, and the provider wants to smooth out the traffic to avoid overwhelming the downstream provider edge router. The provider also wants to ensure that the customer's traffic never exceeds 8 Mbps on average, but can burst up to 10 Mbps for short periods. Which QoS mechanism should be used on the PE router's egress interface?

   • AWRED with a maximum threshold of 8 Mbps
   • BTail drop with a queue limit of 8 Mbps
   • CTraffic policing with a committed information rate (CIR) of 8 Mbps and a burst size of 10 Mbps
   • DClass-based shaping with a committed information rate (CIR) of 8 Mbps and a burst size of 10 Mbps
   Reveal Solution Discussion Select an answer first
2. 7foundation · easy

   What problem does WRED help to avoid that is associated with traditional tail drop?

   • AMPLS label mismatch
   • BPacket reordering
   • CTCP global synchronization
   • DExcessive buffering delay
   Reveal Solution Discussion Select an answer first
4. 8foundation · easy

   Which statement correctly compares the effect of policing and shaping on traffic?

   • APolicing buffers traffic, while shaping drops traffic
   • BPolicing can cause more packet drops, while shaping can introduce additional delay
   • CShaping and policing have identical effects on traffic
   • DPolicing is always preferred over shaping because it does not add delay
   Reveal Solution Discussion Select an answer first
5. 9foundation · easy

   Which QoS mechanism is used to buffer and delay excess traffic to conform to a configured rate?

   • AWRED
   • BPriority queuing
   • CTraffic policing
   • DTraffic shaping
   Reveal Solution Discussion Select an answer first
6. 10application · medium

   A network engineer is configuring QoS on a service provider core router to manage congestion on a high-speed link. The engineer wants to ensure that voice traffic (DSCP EF) is rarely dropped, while best-effort traffic (DSCP 0) is dropped more aggressively as the queue fills. The engineer also wants to avoid the synchronization effect where multiple TCP flows ramp up and down together. Which mechanism should be configured?

   • APolicing with a rate limit applied to DSCP 0 traffic only
   • BTail drop with a single queue threshold for all traffic
   • CWRED with a lower drop threshold for DSCP 0 and a higher threshold for DSCP EF
   • DShaping with a rate limit applied to the entire queue
   Reveal Solution Discussion Select an answer first