Configure Port Type for VLAN Trunking on Cisco ME 3400 Series Ethernet Access Switches

B.

In this scenario, the service provider is using Cisco ME 3400 series Ethernet Access switches on the access edge of their Metro Ethernet POP. The customer requires the ability to trunk VLANs on the uplink port into the provider network while maintaining a secure access edge implementation.

First, let's define the terms:

• UNI (User Network Interface) is the interface between the service provider's network and the customer's network. This is typically used for customer-facing ports.
• ENI (External Network-to-Network Interface) is the interface between two service provider networks.
• NNI (Network-to-Network Interface) is the interface between two switches in the service provider network.
• Access port is a port that carries traffic for only one VLAN.

In this case, the customer requires the ability to trunk VLANs on the uplink port into the provider network. Therefore, we can eliminate the access port option (D) as it is not capable of carrying traffic for multiple VLANs.

The UNI port (A) is typically used for customer-facing ports and is not recommended for trunking VLANs into the provider network. The ENI port (B) is used for connecting two different service provider networks and is not applicable to this scenario.

Therefore, the correct answer is C - NNI. The NNI port is used for connecting two switches in the service provider network and is capable of carrying traffic for multiple VLANs. Additionally, the NNI port can be configured to maintain a secure access edge implementation by using techniques such as VLAN access control lists (VACLs) or private VLANs (PVLANs).

In summary, the correct port type to configure on the switch to meet the customer's requirements while maintaining a secure access edge implementation is an NNI port.