Latency and Reliability
How to design low-latency transaction screening clients and operate WatchTower safely under real traffic.
Low-latency path
Use server-to-server requests, compact payloads, and deterministic idempotency for real-time screening.
Reliable retries
Plan timeout behavior and duplicate protection before pushing live traffic.
Operational validation
Test decisions, alerts, cases, notifications, reporting, and audit logs during rollout.
What to expect
WatchTower is designed for low-latency transaction screening. The fastest path is a server-to-server request with a stable payload, a valid organization API key, and deterministic idempotency.
End-to-end latency still depends on the client network, source-system location, payload size, retries, and any middleware sitting between your system and WatchTower.
The most useful benchmark is from your own staging or production network, not only from a local laptop or browser console.
Inline decision path
For real-time integrations, the client sends a transaction event, WatchTower authenticates the organization, normalizes the payload, evaluates monitoring controls, and returns a decision response.
Any investigation workflow that follows, such as alerts, cases, notifications, reporting, or audit activity, should be treated as operational follow-through around the decision.
Design for
- short request timeouts
- stable idempotency keys
- small but complete payloads
- clear handling of allow, review, and block-style outcomes
- client-side logging of request and response metadata
Client timeout guidance
Financial systems should define a timeout and fallback policy before go-live. WatchTower will return structured responses for valid requests, but clients still need safe behavior for network failures, connection drops, and upstream timeout handling.
Plan for
- network timeout
- transient 5xx response
- duplicate retry
- malformed payload
- authentication failure
- delayed operational notification
Reliability controls
Use these controls during rollout
- idempotency keys for every transaction event
- separate sandbox and production API keys
- connection health checks before traffic ramp-up
- last-success and last-error monitoring
- audit review for sensitive settings and key changes
- alert and case workflow validation after ingestion tests
Load and spike testing
Before moving high-volume traffic, test both steady traffic and burst traffic. A good test should confirm response shape, decision handling, duplicate protection, alert creation, case creation, notification delivery, and reporting updates.
Test scenarios
- steady low-volume ingestion
- short burst traffic
- controlled suspicious transaction
- duplicate retry using the same idempotency key
- invalid API key
- malformed payload
- notification delivery after alert creation