ZyXEL Communications P-660HN-F1 User Manual

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Chapter 14 802.1Q/1P
P-660HN-F1 User’s Guide
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PVC
A virtual circuit is a logical point-to-point circuit between customer sites. Permanent means 
that the circuit is preprogrammed by the carrier as a path through the network. It does not need 
to be set up or torn down for each session. 
Forwarding Tagged and Untagged Frames
Each port on the device is capable of passing tagged or untagged frames. To forward a frame 
from an 802.1Q VLAN-aware device to an 802.1Q VLAN-unaware device, the ZyXEL 
Device first decides where to forward the frame and then strips off the VLAN tag. To forward 
a frame from an 802.1Q VLAN-unaware device to an 802.1Q VLAN-aware switch, the 
ZyXEL Device first decides where to forward the frame, and then inserts a VLAN tag 
reflecting the ingress port's default VID. The default PVID is VLAN 1 for all ports, but this 
can be changed.
Whether to tag an outgoing frame depends on the setting of the egress port on a per-VLAN, 
per-port basis (recall that a port can belong to multiple VLANs). If the tagging on the egress 
port is enabled for the VID of a frame, then the frame is transmitted as a tagged frame; 
otherwise, it is transmitted as an untagged frame.
14.1.3  802.1Q/1P Example
This example shows how to configure the 802.1Q/1P settings on the ZyXEL Device.
Figure 126   802.1Q/1P Example
LAN1 and LAN2 are connected to ATAs (Analogue Telephone Adapters) and used for VoIP 
traffic. You want to create high priority for this type of traffic, so you want to group these ports 
into one VLAN (VLAN2) and then to a PVC (PVC1) where the priority is set to high level of 
service.
You would start with the following steps.
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VoIP Network
Internet - (PPPoE)
Internet - (PPPoE)
P-660HN-F1