A dedicated circuit can be technically up while production traffic still fails. The difficult work is usually not ordering the link. It is agreeing on prefixes, route ownership, DNS behavior, test traffic, maintenance and the exact handoff between the carrier, cloud provider and internal network team.
Describe direction and purpose
Record source, destination, ports, expected volume and which side opens the session. The phrase bidirectional connectivity is too vague for firewall and return-route design.
Review advertised and return routes together
Filter permitted prefixes, cap route counts and validate the return path. A correct forward route with an asymmetric return can look like an application timeout.
Test DNS and large packets
Conditional forwarding, resolver failure and TTL behavior need explicit tests. Ping is not enough; send TLS and large payloads to expose MTU and path discovery failures.
Prove that redundancy is independent
Two circuits do not provide resilience when they share a building entry, device or carrier path. Run failure drills and document detection, escalation and ownership before go-live.