Network Virtualization using Extreme Fabric Connect

Network Virtualization Using Extreme Fabric Connect
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Caution
Transparent UNIs should not be assigned to the same I-SID as CVLAN or Switched UNI.
Figure 32 Transparent UNI
E-TREE / L2 VSNs with Private-VLAN UNI
An E-TREE service type is an enhanced version of an E-LAN L2 VSN that uses a CVLAN UNI where the
VLAN used is a Private-VLAN. A Private-VLAN is a special VLAN construct where port members can be
assigned one of three possible roles:
• Promiscuous role: Devices connected to these ports are able to communicate with every other
device in the same L2 segment. Promiscuous ports are usually untagged ports that are only
members of the Private-VLAN.
• Isolated role: Devices connected to these ports are only able to communicate with devices hanging
off Promiscuous ports. Isolated ports are usually untagged ports that are only members of the
Private-VLAN.
• Trunk role: These ports must be used to q-tag extend a Private-VLAN between two switches. A
Trunk port is always q-tagged and can carry one or more Private-VLANs as well as other regular
VLAN ids.
When a Private-VLAN is created, it is necessary to provide two VLAN-IDs: a Primary VID and a Secondary
VID. In general, a Promiscuous port will always transmit traffic on the primary VID but will receive traffic
from both the primary and secondary VIDs. An Isolated port will transmit traffic into the secondary VID and
will only receive traffic from the primary VID. Both VIDs share the same MAC table and are both q-tagged
on Trunk ports. This is the industry standard IEEE 802.1Q implementation of Private-VLANs used by many
networking vendors as well as server hypervisor vendors such as VMware with ESX.
Extreme Networks Fabric Connect conforms to this implementation and enhances it to seamlessly operate
over the SPB Fabric by being able to assign an L2 VSN I-SID to a Private-VLAN with end-point provisioning.