Where will the broadcast propagate?

Refer to the exhibit. VTP has been enabled on the trunk links between all switches within the
TEST domain. An administrator has recently enabled VTP pruning. Port 1 on Switch 1 and
port 2 on Switch 4 are assigned to VLAN 2. A broadcast is sent from the host connected to
Switch 1. Where will the broadcast propagate?

A.
Every switch in the network receives the broadcast and will forward it out all ports.

B.
Every switch in the network receives the broadcast, but only Switch 4 will forward it out
port 2.

C.
Switches 1, 2, and 4 will receive the broadcast, but only Switch 4 will forward it out port 2.

D.
Only Switch 4 will receive the broadcast and will forward it out port 2.

Explanation:
The default behavior of a switch is to propagate broadcast and unknown packets across the
network. This behavior results in a large amount of unnecessary traffic crossing the network.
VTP pruning increases bandwidth efficiency by reducing unnecessary flooding of traffic,
such as broadcast, multicast, unknown, and flooded unicast packets. VTP pruning increases

available bandwidth by restricting flooded traffic to those trunk links that the traffic must use
to access the appropriate network devices. By default, VTP pruning is disabled.
Enabling VTP pruning on a VTP server enables pruning for the entire management domain.
VTP pruning takes effect several seconds after it is enabled. By default, VLANs 2 through
1000 or 2 through 1001 are pruning eligible, depending upon the platform. VTP pruning does
not prune traffic from VLANs that are pruning ineligible. VLAN 1 is always pruning ineligible
and VLAN 1 cannot be removed from a trunk. However, the “VLAN 1 disable on trunk”
feature available on Catalyst 4000, 5000, and 6000 family switches enables the pruning of
user traffic, but not protocol traffic such as CDP and VTP, for VLAN 1 from a trunk. Use the
vtp pruning command to make VLANs pruning eligible on a Cisco IOS-based switch.
Switch(vlan)#vtp pruning
Once pruning is enabled, use the switchport trunk pruning command to make a specific
VLAN pruning ineligible.
Switch(config)#interface fastethernet 0/3
Switch(config-if)#switchport trunk pruning vlan remove vlan 5