Description of problem:IEEE 802.1ad (Q-in-Q or VLAN Stacking)

Purpose: Allows multiple VLAN tags in a single Ethernet frame by stacking VLANs (customer VLAN inside provider VLAN).
Tag structure:
    •     Outer tag (S-VLAN): TPID = 0x88A8 (Service tag)
    •    Inner tag (C-VLAN): TPID = 0x8100 (Customer tag)
    •    VLAN range per tag: 4094 (S-VLAN) × 4094 (C-VLAN) → enables scaling to millions of customer VLANs
Use Case:
    •    Carrier Ethernet, OpenStack with multiple tenants across L2 boundaries, bridging isolated tenant VLANs across providers

https://bugzilla.redhat.com/show_bug.cgi?id=1846018
https://bugzilla.redhat.com/show_bug.cgi?id=1465393
https://bugzilla.redhat.com/show_bug.cgi?id=1846019

Where cu applied the hotfix for {}ovn vlan transparency{}, now this is the rew enhancement request --> where it is necessary to support 802.1ad as a workaround in case where the hardware(NIC) is not compatible with the double 802.1q.