Multicast is essential for multimedia, video surveillance, and other scenarios, such as airports and stock exchanges. In past test setups, PIM/EVPN Gateway (PEG) connected only a single PIM domain to a single EVPN domain. To address the need for interconnecting multiple EVPN domains, we tested EVPN-to-EVPN Gateways (EEG), as described in draft-rabnic-bess-evpn-mcast-eeg.

In this test case, we verified the EVPN Layer-3 interconnect scenario in the draft. The EEGs synchronize and redistribute multicast interests between EVPN domains using BGP EVPN RT-6 routes. The elected Supplementary Broadcast Domain – Designated Router (SBD-DR) ensures that traffic is transmitted across domains only when needed, minimizing unnecessary flooding and avoiding suboptimal routing. The external PIM domain had PIM-SSM enabled. The Interconnect Ethernet Segment (I-ES) links two VXLAN domains, while Domain Path (D-PATH) mechanisms prevent loops.

We used Keysight IxNetwork to send IGMPv3 joins and observed that EVPN RT-6 (SMET) were generated, and the source was updated to the EEG's route ID. We then sent bidirectional multicast flows and confirmed there was no packet loss or duplication.