Installation manual

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SIGNAMAX LLC • www.signamax.eu
CLI – This example sets port 3 to accept only tagged frames, assigns PVID 3 as the
native VLAN ID, enables GVRP, sets the GARP timers, and then sets the switchport
mode to hybrid.
Configuring IEEE 802.1Q Tunneling
IEEE 802.1Q Tunneling (QinQ) is designed for service providers carrying traffic for
multiple customers across their networks. QinQ tunneling is used to maintain
customer-specific VLAN and Layer 2 protocol configurations even when different
customers use the same internal VLAN IDs. This is accomplished by inserting Service
Provider VLAN (SPVLAN) tags into the customer’s frames when they enter the service
provider’s network, and then stripping the tags when the frames leave the network.
A service provider’s customers may have specific requirements for their internal VLAN
IDs and number of VLANs supported. VLAN ranges required by different customers in the
same service-provider network might easily overlap, and traffic passing through the
infrastructure might be mixed. Assigning a unique range of VLAN IDs to each customer
would restrict customer configurations, require intensive processing of VLAN mapping
tables, and could easily exceed the maximum VLAN limit of 4096.
QinQ tunneling uses a single Service Provider VLAN (SPVLAN) for customers who have
multiple VLANs. Customer VLAN IDs are preserved and traffic from different customers is
segregated within the service provider’s network even when they use the same
customer-specific VLAN IDs. QinQ tunneling expands VLAN space by using a
VLAN-in-VLAN hierarchy, preserving the customer’s original tagged packets, and adding
SPVLAN tags to each frame (also called double tagging).
A port configured to support QinQ tunneling must be set to tunnel port mode. The Service
Provider VLAN (SPVLAN) ID for the specific customer must be assigned to the QinQ
tunnel access port on the edge switch where the customer traffic enters the service
provider’s network. Each customer requires a separate SPVLAN, but this VLAN supports
all of the customer's internal VLANs. The QinQ tunnel uplink port that passes traffic from
the edge switch into the service provider’s metro network must also be added to this
SPVLAN. The uplink port can be added to multiple SPVLANs to carry inbound traffic for
different customers onto the service provider’s network.
When a double-tagged packet enters another trunk port in an intermediate or core switch
in the service provider’s network, the outer tag is stripped for packet processing. When
the packet exits another trunk port on the same core switch, the same SPVLAN tag is
again added to the packet.
Console(config)#interface ethernet 1/3 4-186
Console(config-if)#switchport acceptable-frame-types tagged 4-245
Console(config-if)#switchport ingress-filtering 4-245
Console(config-if)#switchport native vlan 3 4-246
Console(config-if)#switchport gvrp 4-239
Console(config-if)#garp timer join 20 4-240
Console(config-if)#garp timer leave 90
Console(config-if)#garp timer leaveall 2000
Console(config-if)#switchport mode hybrid 4-244
Console(config-if)#