# Coherent planning inputs

Keep exact operating modes, line-system conditions and optical measurements together before evaluating a coherent route.

Revision 2026-11-01. Planning inputs only; unresolved conditions are not approval.

## Endpoint and mode identity

A shared rate or media code does not prove equivalent modes. Record the exact model, revision and application at both ends.

- **Route ID / date / endpoint identities:**

- **A and Z module / firmware / source document revision:**

- **Host framing, multiplexing and electrical lane map:**

- **Line format, payload, modulation, baud rate and FEC:**

- **Channel frequency / grid / spacing / filter passband:**

## Line system and optical conditions

Record OSNR reference bandwidth, measurement point and receive power together. Receiver sensitivity, overload, monitor range and absolute maximum ratings are separate quantities.

- **Span losses / amplifier or ROADM stages / filter path:**

- **Transmit power setting and allowed range:**

- **Receive signal power and total power, per endpoint:**

- **Measured OSNR, reference bandwidth, method and location:**

- **Chromatic dispersion / PMD / mode compensation range:**

- **Amplifier gain, noise, loading and launch constraints:**

## Power, thermal and qualification record

Power can depend on host mapping, line mode and dispersion range. Missing test conditions remain unresolved.

- **Host power budget and documented mode-specific draw:**

- **Module case temperature, cold start and cooling conditions:**

- **Pre/post-FEC error record with time interval and units:**

- **Interoperability / soak evidence and unresolved limits:**