L2VPN VPN Label Calculation

L2VPN VPN Label Calculation

L2VPN always advertise a block of labels Remote sites calculate the labe they should use based on their Site ID

Label Blocks Label Base Site ID Offset

root@PE> show configuration routing-instances my-customer-1
instance-type l2vpn;
interface ge-0/0/0.0;
route-distinguisher 192.168.1.1:100;
vrf-target target:64501:100;
protocols { 
    l2vpn {
         encapsulation-type ethernet;
         site customer-1-site-1 {
         				site-identifier 1;
         				interface ge-0/0/0.0; {
         				    remote-site-id 5;
         				}
         				
         }
    }
}

Label-base : 800000

Offset: 5

Connection-site : 5

Incoming Label: 800000

Outgoing Label: 800000X

VPN Label = Label Base + (Remote-site-identifier – offset)

=800000+(5-5)

=800000

We configured only site IDs, but not the label base and offset values;

Offset, default value is 32 that means, we can have maximum 32 sites (0 to 31)

Label base default value is 800000.

If we want more than 32 sites, we can configure another label base (multiple starting points)