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ONFIGURING

VLAN S

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Configuring VLAN Swapping
QinQ tunneling uses double tagging to preserve the customer’s VLAN
tags on traffic crossing the service provider’s network. However, if any
switch in the path crossing the service provider’s network does not
support this feature, then the local switches connected directly to the
customer can be manually configured to swap the customer’s VLAN ID
with the service provider’s VLAN ID.
General Configuration Guidelines for VLAN Swapping
1. Configure the switch to VLAN-swap mode
(see “Selecting the VLAN Operation Mode” on page 13-1).
2. For traffic entering the switch through a downlink port attached to a
customer (i.e., inbound port and VLAN) and exiting through an uplink
port attached to a service provider (i.e., outbound port and VLAN),
map the inbound to outbound port, and inbound to outbound VLAN.
3. For traffic entering the switch through an uplink port attached to a
service provider (i.e., inbound port and VLAN) and exiting through an
downlink port (i.e., outbound port and VLAN), map the inbound to
outbound port, and inbound to outbound VLAN.
Command Usage
• VLAN swapping only supports one-to-one mapping of VLAN IDs
between a VDSL port and an uplink port.
• VLAN IDs must be mapped for both the upstream and downstream
direction.
• The maximum number of VLAN swap entries is 64 per port groups 1-8,
9-16, 17, and 18. However, note that configuring a large number of
entries may degrade the performance of other processes that also use the
Fast Forwarding Processor (FFP) table, such as access lists, rate limiting,
and IP filtering.