What results if a Catalyst 3550 switch drops the tagged frames or blocks tagged traffic?
The Catalyst 3550 switch does not normally accept 802.1Q tagged frames on access ports. You have to enable features that require these frames to be forwarded, such as QinQ (IEEE 802.1ad or VLAN double tagging or IEEE 802.1q tunneling) or a voice VLAN. The Catalyst 3750/3560/2970/2960 switches are also normally configured to drop priority tagged frames that are received on access ports unless the QinQ or voice VLAN is configured.
