View the exhibit.
Exhibit 1

Exhibit 2

A network that handles IPv6 multicasts and the hosts that have joined particular IPv6 multicast
groups is shown in Exhibit 1. Routing switch B is acting as the MLD querier, and routing switch A
implements MLD snooping, as shown in Exhibit 2.
An IPv6 multicast packet for FF14::1 arrives on routing switch A on port B1. On which ports does
the switch forward the packet?

A.
A1 Forwards – A2 Does not forward – B1 Does not forward – B2 Forwards

B.
A1 Does not forward – A2 Forwards – B1 Forwards – B2 Does not forward

C.
A1 Forwards – A2 Does not forward – B1 Forwards – B2 Does not forward

D.
A1 Does not forward – A2 Forwards – B1 Does not forward – B2 Forwards

Explanation:
A: There is a host on port A1 (of Switch A) that is in the FF14::1 group. So Switch A
will forward this packet on the A1 port.

D: Switch A learns through MLD snooping (see note below) that through port B2 and through
Switch C there is a host that is in the FF14::1 group. So Switch A will forward this packet on the B2
port.
Note: Multicast Listener Discovery (MLD) snooping constrains the flooding of IPv6 multicast traffic
on VLANs on a switch. When MLD snooping is enabled on a VLAN, a Switch examines MLD
messages between hosts and multicast routers and learns which hosts are interested in receiving
traffic for a multicast group. Based on what it learns, the switch then forwards multicast traffic only
to those interfaces in the VLAN that are connected to interested receivers instead of flooding the
traffic to all interfaces.