Application Guide

[182]
Software User's
Manual
–
Version 3.0
Setting Description
Mode
The port mode (default is Access) determines the fundamental behavior of the
port in question. A port can be in one of three modes as described below.
Whenever a particular mode is selected, the remaining fields in that row will be
either grayed out or made changeable depending on the mode in question.
Grayed out fields show the value that the port will get when the mode is
applied.
Access:
Access ports are normally used to connect to end stations. Dynamic features
like Voice VLAN may add the port to more VLANs behind the scenes. Access
ports have the following characteristics:
 Member of exactly one VLAN, the Port VLAN (a.k.a. Access VLAN),
which by default is 1
 Accepts untagged and C-tagged frames
 Discards all frames not classified to the Access VLAN
 On egress all frames are transmitted untagged
Trunk:
Trunk ports can carry traffic on multiple VLANs simultaneously and are
normally used to connect to other switches. Trunk ports have the following
characteristics:
 By default, a trunk port is a member of all VLANs (1-4095)
 The VLANs that a trunk port is a member of may be limited by the use of
Allowed VLANs
 Frames classified to a VLAN that the port is not a member of are
discarded
 By default, all frames but frames classified to the Port VLAN (a.k.a.
Native VLAN) get tagged on egress. Frames classified to the Port VLAN
do not get C-tagged on egress
 Egress tagging can be changed to tag all frames, in which case only
tagged frames are accepted on ingress
Hybrid:
Hybrid ports resemble trunk ports in many ways, but adds additional port
configuration features. In addition to the characteristics described for trunk
ports, hybrid ports have these abilities:
 Can be configured to be VLAN tag unaware, C-tag aware, S-tag aware,
or S-custom-tag aware
 Ingress filtering can be controlled
 Ingress acceptance of frames and configuration of egress tagging can
be configured independently