When using the factory-default configuration, which VLAN is assigned to all interfaces on an EX Series switch?

A.
vlan1

B.
native

C.
default

D.
unnumbered

Explanation:
Routed VLAN Interface

In a traditional network, broadcast domains consist of either physical ports connected to a single switch or logical ports connected to one or more switches through VLAN configurations. Switches send traffic to hosts that are part of the same broadcast domain, but routers are needed to route traffic from one broadcast domain to another and to perform other Layer 3 functions such as traffic engineering. EX-series switches use a routed VLAN interface (RVI) to perform these routing functions, using it to route data to other Layer 3 interfaces. This functionality eliminates the need for having both a switch and a router.

The RVI interface must be configured as part of a broadcast domain or VPLS routing instance in order for Layer 3 traffic to be routed out of it. The RVI interface supports IPv4, IPv6, MPLS, and ISIS traffic. At least one Layer 2 logical interface should be operationally up in order for the RVI interface to be operationally up. You must configure an RVI broadcast domain or VPLS routing instance just as you would configure a VLAN on a switch. Multicast data, broadcast data, or unicast data is switched between ports within the same RVI broadcast domain or VPLS routing instance. The RVI interface routes data that is destined for the routers media access control (MAC) address.