.. include:: /_include/need_improvement.txt IEEE 802.1ad_ was an Ethernet networking standard informally known as QinQ as an amendment to IEEE standard 802.1q VLAN interfaces as described above. 802.1ad was incorporated into the base 802.1q_ standard in 2011. The technique is also known as provider bridging, Stacked VLANs, or simply QinQ or Q-in-Q. "Q-in-Q" can for supported devices apply to C-tag stacking on C-tag (Ethernet Type = 0x8100). The original 802.1q_ specification allows a single Virtual Local Area Network (VLAN) header to be inserted into an Ethernet frame. QinQ allows multiple VLAN tags to be inserted into a single frame, an essential capability for implementing Metro Ethernet network topologies. Just as QinQ extends 802.1Q, QinQ itself is extended by other Metro Ethernet protocols. In a multiple VLAN header context, out of convenience the term "VLAN tag" or just "tag" for short is often used in place of "802.1q_ VLAN header". QinQ allows multiple VLAN tags in an Ethernet frame; together these tags constitute a tag stack. When used in the context of an Ethernet frame, a QinQ frame is a frame that has 2 VLAN 802.1q_ headers (double-tagged). In VyOS the terms ``vif-s`` and ``vif-c`` stand for the ethertype tags that are used. The inner tag is the tag which is closest to the payload portion of the frame. It is officially called C-TAG (customer tag, with ethertype 0x8100). The outer tag is the one closer/closest to the Ethernet header, its name is S-TAG (service tag with Ethernet Type = 0x88a8). .. cmdinclude:: /_include/interface-address-with-dhcp.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-description.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-disable.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-disable-link-detect.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-mac.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-mtu.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-ip.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-ipv6.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-vrf.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 **DHCP(v6)** .. cmdinclude:: /_include/interface-dhcp-options.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-dhcpv6-options.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. cmdinclude:: /_include/interface-dhcpv6-prefix-delegation.txt :var0: {{ var0 }} :var1: {{ var1 }} :var2: vif-s :var3: <vlan-id> :var4: 1000 :var5: vif-c :var6: <vlan-id> :var7: 20 .. include:: /_include/common-references.txt