You can configure IS-IS traffic engineering to store IPv6 information in the traffic engineering database (TED) in addition to IPv4 addresses. BGP-LS distributes this information as routes from the TED to the lsdist.0 routing table using the TED import policies. These routes are advertised to BGP-TE peers as network layer reachability information (NLRI) with IPv6 router ID type, length, and value (TLV).
With this enhancement, you can benefit from obtaining the complete network topology in the TED.