Network Virtualization using Extreme Fabric Connect

Network Virtualization Using Extreme Fabric Connect
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access to certain video surveillance multicast streams. As both VSNs ultimately operate on the same
Ethernet Fabric infrastructure, it would not make sense to duplicate the surveillance cameras IP Multicast
streams across both VSNs. This would be inefficient, as it would potentially result in the same IP Multicast
packets being transmitted twice over the Ethernet Fabric core. With IP multicast, the most efficient
approach is always to create a replication branch on the furthest node along the shortest path. This is what
Fabric Connect does in the core and this is what can also be achieved on the last Fabric Attach hop using
Multicast VLAN Registration (MVR).
Figure 49 Inter-VSN IP Multicast with MVR on FA Proxy
The MVR function operates on a standard L2 Ethernet switch, which in the Extreme Fabric architecture will
be operating as an FA Proxy, and designates one MVR source VLAN (MVR-S) and a number of MVR
Receiver VLANs. The MVR source VLAN only needs to be present on the FA Proxy uplinks while the MVR
Receiver VLANs are regular user CVLANs; both can be provisioned using Fabric Attach I-SID signalling. Any
IGMP request from users within the MVR Receiver VLANs can be made to trigger an IGMP Report (Join) on
the MVR Source VLAN. Once the requested IP multicast stream is received on the upstream MVR source
VLAN, it will also be IGMP snooped on the receiver ports of the relevant MVR receiver VLANs where the
end-users had IGMP signalled an interest in receiving the multicast stream.
Tip
Extreme Networks supports MVR on the ExtremeXOS and ERS 4900 and 5900 platforms.
The MVR global configuration on the access switch will define an IP Multicast Class D range of authorized IP
Multicast streams, which will thus be allowed to traverse the VSN domain to which they belong into any of
the local CVLANs designated as MVR Receiver VLANs.
Tip
An MVR Receiver VLAN can receive IP multicast via the MVR Source VLAN (if multicast
Group address requested falls into MVR range), as well as natively on the same VLAN (if
multicast Group address requested does not fall into MVR range). This means that the red
or blue or grey users in Figure 49 can receive IP multicast from the green VSN, but can
also receive other IP multicast streams from within their own VSNs.
In the example shown in Figure 49, notice that the intent is that the VSN, which naturally owns the IP
multicast source, is also able to have users and multicast receivers locally on the same VSN. MVR comes
with one limitation, namely that no IGMP receivers are allowed on the MVR source VLAN, so the correct
design approach to achieve the design goal is to designate a separate L2 segment (VLAN) for the MVR