Traffic testing was performed across all nodes to ensure proper forwarding in a multi-vendor environment. This validation included verifying that each PE had routes installed with the next-hop set as an SRv6 SID. In addition, every PE was to have assigned SRv6 Locators and Function SIDs (End.DT4 with NEXT-CSID, End.DT6 with NEXT-CSID, End.DT46 with NEXT-CSID) for L3VPN services. With stable IS-IS adjacencies checked, SRv6 locators were also validated for proper advertisement and reachability. The presence of VPN prefixes in the RIB was confirmed, ensuring end-to-end connectivity.
As part of our interoperability validation, apart from uSID (NEXT-CSID compression flavor), we included as well G-SID (Generalized SID - REPLACE-CSID compression flavor) testing for the first time in an SRv6 L3VPN deployment.

To verify the control-plane behavior, we first checked that  IS-IS properly advertised SRv6 G-SIDs in TLVs, ensuring correct locator propagation across the network. We also examined  BGP VPNv4/VPNv6 routes, confirming that VPN prefixes were advertised with an  SRv6 G-SID as the next-hop .
Finally, we conducted end-to-end traffic testing between VPN endpoints, verifying that  traffic was correctly forwarded.