A collector at an exchange is fed over one IPv6 session that carries
both families, with ADD-PATH for both and IPv4 routes with IPv6 next
hops (RFC 8950). The integration test for that has the collector on
IPv6 loopback with those capabilities and two feeders sending 20,000
IPv4 and 1,000 IPv6 prefixes each, and checks that every route of both
families arrives with its identifier. The test helper now reads the
prefixes that come and go in the multiprotocol attributes too.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>