ENNI Ports

An ENNI port is also known as an “external network-to-network interface,” as defined in MEF 26.

ENNIs allows Q-in-Q tunneling, also known as IEEE 802.1ad or “stacked VLANs.” While carriers commonly use this to manage customer traffic, individuals might have various uses for Q-in-Q as well.

For more information on business use cases, see ENNI Support for Q-in-Q, Network Extension and Backbone Expansion.

Provision an ENNI port

Create a port as you normally would. On the Port Details step, you will be given the option to create an ENNI port:

Q-in-Q

With Q-in-Q tunneling, an Ethernet frame has two VLAN tags:

• C-VLAN - Also known as the “Customer VLAN.” This is the inner tag.
• S-VLAN - Also known as the “Service VLAN.” This is the outer tag.

You can use the S-VLAN to bundle and direct traffic, while still maintaining the C-VLAN identifier.

Technical notes

• The default TPID value is 0x8100.
• You cannot combine non-ENNI and ENNI ports together in a LAG.
• You can have multiple EPL virtual circuits on an ENNI port.
• To convert an ENNI port to a standard access port, you must contact support@packetfabric.com.

S-VLAN labels

Once you have an ENNI port provisioned, you can add labels to S-VLAN tags. For more information, see S-VLAN Labels.

Use case 1: ENNI to ENNI

This is essentially an EVPL connection.

Provider A has a customer who needs a virtual circuit between two locations on the provider’s network, and Provider A has NNIs with PacketFabric at those locations. Therefore, Provider A uses PacketFabric’s network to build the circuit.

Note the following:

• The S-VLAN is unique to the NNI termination and does not need to match between NNIs.
• If the customer wants different C-Tags to go on different EVCs then they must put the appropriate S-Tag on the frame. PacketFabric will not look at the C-Tag to steer traffic between two ENNI endpoints.

Click to expand:

Use case 2: ENNI to access port

Provider A has a customer who needs a virtual circuit between one of the provider locations and a location on the PacketFabric network. Provider A orders an access port for the customer and the cross connect is arranged.

Provider A then builds a virtual between their NNI and the access port. There are 3 combinations of delivery, shown top to bottom:

• EVC A - Untagged EPL access port to ENNI with an S-Tag and C-Tag, both of which must be removed at the ENNI.
• EVC B - Untagged EPL access port to ENNI with an S-Tag, which must be removed at the ENNI.
• EVC C - EVPL access port with C-Tag to ENNI with an S-Tag and a C-Tag. The S-Tag must be removed at the ENNI. C-Tag COS must be maintained.

Click to expand:

Use case 3: ENNI to cloud on-ramp

Provider A has a customer who needs a virtual circuit from one of the provider’s locations to one of PacketFabric’s cloud On Ramps. Provider A orders the cloud on-ramp virtual circuit.

Click to expand: