BIC interactions reveal network structure

What the public implementation shows

Guevara models BicInteraction and BicStatistics and implements a BicStatisticsService with settlement BIC statistics queries.

The analytical service derives participant relationship views from governed transaction and settlement records. This is the implementation fact behind the note; the architectural reading begins from that visible boundary rather than from an assumed production story.

Operating principleA payment network is shaped by relationships between institutions, not only by their individual totals.

The decision behind the mechanism

Pairwise statistics expose direction and counterparty dependence hidden by per-participant totals.

Two participants with equal volume can have very different network roles when one is diversified and the other depends on one corridor. The mechanism matters because it gives that failure a named boundary, durable evidence, and a controlled response instead of leaving the outcome to timing or operator guesswork.

• Use canonical BIC and participant mappings.
• Reconcile pairwise totals to system totals.
• Keep incoming and outgoing direction explicit.
• Restrict sensitive counterparty detail by role.

How the control should be operated

Analysis should preserve period, direction, currency or rail context, count, value, net position, and suppression rules for sensitive small cells.

The operator can investigate concentration and ecosystem development with structural evidence. The reusable lesson is not to copy a class or endpoint in isolation, but to preserve the relationship between identity, state, authority, evidence, and operational ownership.