inS_cnge2fe16MS_reV–
01/11/12 Page 71
INSTALLATION AND OPERATION MANUAL
CNGE2FE16MS
TECh SUPPORT: 1.888.678.9427
particular VLAN group, except it is on a Trunk/Hybrid Link.
The technique of 802.1Q tagging inserts a 4-byte tag, including VLAN ID of the destination port—
PVID, in the frame. With the combination of Access/Trunk/Hybrid Links, the communication across
switches also can make the packet sent through tagged and untagged ports.
This switch supports IEEE 802.1Q-in-Q or IEEE 802.1ad standard developed to break through the
limitation of 802.1Q for multi-VLAN environments where the amount of VLAN may exceeds 4096.
Q-in-Q allows a given Ethernet frame with two VLAN headers inserted, known as doubled-tagged
or stacked VLANs. And therefore, a double-tagged frame is sufficient to accommodate the
amount of VLANs up to 4096 x 4096 = 16777216.