Industrial Software Integration & APIs worked example

Integration Downtime Exposure at 29% cascading failure allowance: a worked example

This scenario runs the integration downtime exposure calculation on the strong side: 29% cascading failure allowance, with every other input held at its documented default. Use this calculator when quantifying the risk of integration downtime for SLA planning, disaster recovery budgeting, or justifying redundancy investments in middleware or API gateways.

The inputs for this scenario

  • Expected integration outage events per year: 6 events (unchanged)
  • Average MTTR per outage: 4 hours / event (unchanged)
  • Cascading failure allowance: 29 % (raised for this scenario; the documented default is 25)

Working through the calculation

  • Applying the documented formula (Base downtime exposure = expected outage events x average MTTR) to the inputs above produces each figure below.
  • At this operating point the engine returns 1.94 hr for total annual downtime exposure (hours), the number this scenario is built around.
  • At this operating point the engine returns 1.5 hr for base downtime from direct outages.
  • At this operating point the engine returns 29 % for cascading failure hours added.
  • At this operating point the engine returns 4 pieces / min for average mttr (hours/event).

How this compares with the baseline

  • Against the tool's baseline example, where cascading failure allowance sits at 25% and the headline result is 1.88 hr, this scenario comes in 3.2% above the baseline at 1.94 hr.
  • Use it when setting integration SLAs, planning resilience investments, or quantifying the case for redundant middleware. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Total annual downtime exposure (hours): 1.94 hr (headline result)
  • Base downtime from direct outages: 1.5 hr
  • Cascading failure hours added: 29 %
  • Average MTTR (hours/event): 4 pieces / min

Run it with your numbers

  • Every input above is editable in the live Integration Downtime Exposure calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.