Advanced Features; Vlans; All Ports Untagged - Zhone zNID-GPON-2402 Configuration Manual

Advanced features

VLANS

The zNID 24xxs support VLAN-based services. This section describes the
types of VLANs that are supported on this device. When configured for
normal single-tagged mode, all ports are members of a VLAN. They can be
untagged or tagged members. Alternatively, ports can be double tagged
members of an S-VLAN.
Ethernet frames that are tagged have a VLAN ID and priority as part of the
Ethernet frame. In this product that is called the "C" tag or the Customer tag.
This family of products also supports the double tagging feature. The outer
tag is called the "S-Tag" or the Service Provider tag. This double tag
capability is an advanced feature that allows traffic from multiple clients to be
sent through the network in a common VLAN.
Once the S-Tag mode has been selected from the VLAN Mode page, traffic
leaving the port designated as the S-Tag port, will have the outer S-tag added
to the frame.
The S-Tag mode only works with ports that been defined as TLS members for
the S-LAN, where all tagged traffic on a port is accepted without having to
configure each individual VLAN. When this traffic leaves the system, it will
have the outer S-tag applied to the packets.

All ports untagged

In some configurations the Ethernet ports appear as untagged ports. The
traffic in and out of the ONU will be standard Ethernet frames. However,
internally, the Ethernet frames are VLAN tagged (C-1). This allows the ONU
to prioritize and forward traffic appropriately. The figure below shows the
traffic flow for ports that are untagged.
Figure 155: All ports untagged
This configuration is valid only when all ports are members of the same
VLAN. Otherwise, there is no way to separate traffic. This configuration
would not typically be used when the zNID 24xx is connected to an MXK.
The MXK expects the traffic to be tagged, as described in the next section.
Advanced features
zNID 24xx Series Configuration Guide
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