• Description: CCIE Pre-Qualification Test for Security
• Passing Score: 75%
• Practice Test - Number of questions: 391 questions
• Simulation Test - Number of questions: 391 questions
• Simulation Test Duration: 41 minutes
• Has explanations: No

How does QoS interact with VPN encapsulation?

Answer(s)

1. QoS cannot be used with VPN because the TOS bits in the IP header are not written to the outside IP header of an ESP packet therefore no increased performance is gained.
2. QoS is commonly used to prioritize the process switching of all VPN packets at both endpoints except when NAT is applied at either endpoint.
3. QoS IP header bits are copied between the original packet and the IP header encapsulating the VPN tunnel.
4. QoS cannot be used with VPN because the TOS bits in the IP header are not written when traversing a Router.

QoS IP header bits are copied between the original packet and the IP header encapsulating the VPN tunnel.