Network & Infrastructure / Segmentation, TLS & Secure Connectivity
Microsegmentation rules derived from observed dependencies
A team proposes blocking all east-west traffic except flows seen in one day's capture. Rare backup, recovery and authentication dependencies may be absent from that sample.
Environment and inputs: Stateful network boundaries, TLS endpoints and IPsec gateways; use the deployed security policy and implementation manual. Diagnostic/design example; not tested on production equipment.
Collect the evidence
Combine observed flows with application ownership, scheduled jobs, recovery procedures and documented management paths. Label each permitted dependency with purpose, direction and identity rather than only a port number.
Explain the result
An observation window shows what happened during that period, not everything required during failure or maintenance. Blindly converting it to policy can turn an ordinary recovery into an outage.
Plan the fix
Build a reviewed dependency model and stage enforcement with meaningful deny telemetry. Keep explicit emergency access and its ownership within the approved operational design.
Check the result and rollback
Exercise normal operation, backup, restore and authentication failover before broad enforcement. Revert the affected rule set if essential recovery traffic is blocked, then add the justified dependency with evidence.