Configuring Q-in-Q Tunneling on ACX Series
SUMMARY
Q-in-Q Tunneling on ACX Series Overview
Q-in-Q tunneling allows service providers to create a Layer 2 Ethernet connection between two customer sites. Providers can segregate different customers’ VLAN traffic on a link (for example, if the customers use overlapping VLAN IDs) or bundle different customer VLANs into a single service VLAN. Service providers can use Q-in-Q tunneling to isolate customer traffic within a single site or to enable customer traffic flows across geographic locations.
Q-in-Q tunneling adds a service VLAN tag before the customer’s 802.1Q VLAN tags. The Juniper Networks Junos operating system implementation of Q-in-Q tunneling supports the IEEE 802.1ad standard.
In Q-in-Q tunneling, as a packet travels from a customer VLAN (C-VLAN) to a service provider's VLAN (S-VLAN), another 802.1Q tag for the appropriate S-VLAN is added before the C-VLAN tag. The C-VLAN tag remains and is transmitted through the network. As the packet exits from the S-VLAN space, in the downstream direction, the S-VLAN 802.1Q tag is removed.
In ACX Series routers, you can configure Q-in-Q tunneling by
explicitly configuring an input VLAN map with push function
on customer facing interfaces in a bridge domain.
You can configure Q-in-Q tunneling on aggregated Ethernet interface by configuring input and output VLAN map.
Configuring Q-in-Q Tunneling on ACX Series
To configure Q-in-Q tunneling, you need to configure the logical interface connected to the customer network (user-to-network interfaces (UNI)) and the logical interface connected to the service provider network (network-to-network interface (NNI)).
The following is an example to configure a logical interface connected to a customer network:
[edit]
interface ge-1/0/1 {
flexible-vlan-tagging;
encapsulation flexible-ethernet-services;
unit 0 {
encapsulation vlan-bridge;
vlan-id-list 10-20;
input-vlan-map {
push;
vlan-id 500;
}
output-vlan-map pop;
}
}
The following is an example to configure a logical interface connected to a service provider network:
[edit] interface ge-1/0/2; { flexible-vlan-tagging; encapsulation flexible-ethernet-services; unit 0 { encapsulation vlan-bridge; vlan-id 500; } }
The following is an example to configure the bridge domain:
[edit] bridge-domains { qnq-stag-500{ interface ge-1/0/1; interface ge-1/0/2; } }
You can configure Q-in-Q tunneling on aggregated Ethernet interface connected to the customer network (UNI) and the logical interface connected to the service provider network (NNI).