Verify emulated device frame checksums before dispatch
Corrupted readings reach the dashboard because checksum failures are warnings only. Gate payload dispatch on verification.
- Focused work estimate
- 2h + prerequisites
- Priority in the scenario
- High
- Engineering practice
- Integrity · Protocol design
Estimated field mix
- Embedded and edge60%
- Networking40%
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Review it, then add it to your workspace.
The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.
Project context
Fictional environmental-display devices send synthetic noncritical readings to a local gateway. Implement a byte-stream emulator; no physical device, radio, credentials or safety-critical control is involved.
Setup prerequisites
- Specify a small frame format with length sequence payload and checksum.
- Generate local byte streams with fragmentation corruption and reconnects.
Preceding work
Complete these dependencies, or supply their agreed outputs before taking this ticket.
Acceptance criteria
- Valid frame dispatches once
- Bad checksum dispatches nothing
- Failure records a bounded category
Implementation constraints
- Checksum detects corruption and does not authenticate senders.
Verification to include
- Accept valid frame
- Flip payload byte without updating checksum
Deliverables
- Checksum gate and corruption cases
Rollout and recovery
Disable payload dispatch if verification is unavailable.
Value of the work
For the engineer: Practice incremental parsing, fixed resource limits and protocol recovery.
For the team: Inspect whether a device adapter survives malformed input without corrupting accepted readings.
Evidence boundaries
Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.
Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.