Advanced Configuration Options 45
Model 2160 Series Getting Started Guide 4 • Web configuration
•Tag Protocol Identifier (TPID) is a defined value of 8100 in hex. When a frame has the EtherType equal to
8100, this frame carries the tag IEEE 802.1Q / 802.1P.
•User Priority defines the priority level for different classes of traffic. There are 8 possible priority levels, with
0 being the lowest priority level and 7 being the highest level. IEEE 802.1P defines the operation for these
3 user priority bits.
•Canonical Format Indicator (CFI) is always set to zero for Ethernet switches. CFI is used for compatibility
reasons between an Ethernet-type network and Token Ring-type network. If a frame received at an Ethernet
port has a CFI set to 1, then that frame should not be forwarded as it is to an untagged port.
•VLAN ID (VID) is the unique identification number of the VLAN, which is used by the standard 802.1Q.
It has 12 bits and allows the identification of 4096 (212) VLANs. Of the 4096 possible VIDs, a VID of 0 is
used to identify priority frames and the value 4095 (FFF) is reserved, so the maximum possible VLAN con-
figurations are 4,094.
The Model 2160 initially configures one VLAN by default, VID=1. A port such as LAN1–4, line or sniffing
can have only one Port VID (PVID), but can have as many VID groups as the Model 2160 has memory in its
VLAN table to store them.
Ports in the same VLAN group share the same frame broadcast domin thus increase network performance
through reduced boardcast traffic. You can modify VLAN groups at any time by adding, moving or changing
ports without any re-cabling.
Figure 18. 802.1Q VLAN diagram
Configuring 802.1Q VLAN Tagging. Before enabling VLANs for the Model 2160, you must first assign each
port to the VLAN group(s) in which it will participate. By default all ports are assigned to VLAN1 as untagged
ports. Add a port as a tagged port if you want it to carry traffic for one or more VLANs, and any intermediate
network devices or the host at the other end of the connection supports VLANs. Then, assign ports on the
other VLAN-aware network devices along the path that will carry this traffic to the same VLAN(s), either man-
SERVER
CopperLink Model 2160
Extender connection
LAN1
LAN2
LAN3
LAN4
LAN1
LAN2
LAN3
LAN4
SERVER
VOIP VOIP
802.1Q VLAN
STU-C STU-R
PWRALM DIAG
WAN
LAN 100M
LINK/ACT
LINK
1 2 3 4
CopperLink™2160
Long Range Ethernet Extender
PWRALM DIAG
WAN
LAN 100M
LINK/ACT
LINK
1 2 3 4
CopperLink™2160
Long Range Ethernet Extender
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