Layer 2 Traffic Tunneling (Q-in-Q, L2PT) JN0-650 Practice Questions (Page 2)

Questions 6–10

1. 6foundation · easy

   What is the primary purpose of Layer 2 Protocol Tunneling (L2PT) in a service provider network?

   • ATo route Layer 3 packets between customer networks
   • BTo carry Layer 2 control protocols such as STP and LLDP across the provider network
   • CTo encrypt Layer 2 data traffic between customer sites
   • DTo replace customer STP with the provider's STP
   Reveal Solution Discussion Select an answer first
2. 7foundation · easy

   How does L2PT prevent customer and provider Layer 2 control protocols from interacting?

   • ABy encapsulating customer protocol frames in a special MAC address that the provider ignores
   • BBy dropping all customer control protocol frames at the provider edge
   • CBy replacing the customer's protocol frames with provider-specific frames
   • DBy using a separate VLAN for control protocols
   Reveal Solution Discussion Select an answer first
4. 8application · easy

   A network engineer is analyzing a packet capture from a service provider edge interface that uses Q-in-Q. The capture shows an Ethernet frame with two 802.1Q tags. The customer's original frame had a VLAN ID of 100. The provider assigned an outer tag of 200. Which statement correctly describes the frame structure?

   • AThe frame has two tags of equal priority, and the switch uses both to make forwarding decisions.
   • BThe frame is invalid because Ethernet frames can only carry a single 802.1Q tag.
   • CThe outer tag (100) is the customer VLAN, and the inner tag (200) is the service-provider VLAN.
   • DThe outer tag (200) is the service-provider VLAN, and the inner tag (100) is the customer VLAN.
   Reveal Solution Discussion Select an answer first
5. 9expert · medium

   A service provider is offering a transparent LAN service to a customer that runs Rapid Spanning Tree Protocol (RSTP) and Link Layer Discovery Protocol (LLDP) at their sites. The provider's network uses its own STP and LLDP. The customer wants both RSTP and LLDP to be tunneled across the provider network. What should the provider configure?

   • AEnable L2PT for both RSTP and LLDP on the provider edge interfaces.
   • BUse Q-in-Q to tunnel both RSTP and LLDP frames.
   • CEnable L2PT for RSTP only, as LLDP is not a control protocol.
   • DDisable STP and LLDP on the provider edge interfaces to allow customer frames to pass through.
   Reveal Solution Discussion Select an answer first
6. 10foundation · easy

   In a Q-in-Q frame, what is the role of the inner customer tag?

   • AIt identifies the customer's VLAN and is preserved end-to-end
   • BIt is used by the service provider to forward the frame across the backbone
   • CIt is used to prioritize traffic within the provider network
   • DIt is replaced by the provider's tag at each hop
   Reveal Solution Discussion Select an answer first