DT Etherlink IV
User Manual
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Figure 3.14 Internal Switch (ETH5 is not available for NTU devices)
For single-channel modems the DSL channel is strictly mapped to WAN1, while the E1 interface is
strictly mapped on WAN2.
Figure 3.15 Internal Switch for single-channel devices (SA-RC-2DSL_2E1-4Eth-RP)
A group of LANx Ports (Ethernet interface) means the LAN port connector on the front panel or
backplane that can serve as a
Trunk port
,
Access port
or
Mixed port
.
The
Trunk port
is a port where all present packets have the VLAN format, namely, the Ethernet
frame with a header, determining the number of the VLAN and QoS.
In Trunk mode, only tagged
frames pass into and out of LANx port, frames are allowed to pass on per-VLAN basis. This means
that special equipment supporting VLAN is connected to the Trunk port. A PC with a standard
network interface card cannot be connected to the Trunk port.
The
Access port
is a port where all present packets have a standard Ethernet format (without the
additional two bytes for the header). It means that
only untagged frames pass into (ingress) and out
of (egress) any LANx port. On ingress, frames are assigned with a default VLAN tag (configured by
VID and QoS commands). On egress, only frames with VLAN equal to the default VLAN of the port
are allowed, and this tag is removed. A PC with a standard network interface card can be connected
to the Access port.