Why should field definitions be requested?¶

Field definitions should be requested because the label shown in a log does not always explain exactly what the value means.

A familiar heading can hide a vendor-specific or system-specific meaning.

Avoid this assumption: That terms such as user, source, destination, status or success mean the same thing in every system. They do not.

A field labelled “user” might contain the account being authenticated, the account running a process or the administrator who performed an action. “Source IP” might mean the end device, a proxy, a collector or the address visible after network translation.

A “success” value may mean a request was accepted, not that the wider action completed. A timestamp may represent event creation, receipt, processing or display time.

Without definitions, investigators may build a confident but incorrect narrative from technically accurate data.

Field definitions may come from vendor documentation, an administrator, a system owner, an export schema or specialist support. They should explain what created the field, its possible values, its format and any known limitations.

Investigators should request definitions for any field that materially affects identity, timing, sequence, action or outcome. Ask whether fields were renamed, normalised or enriched by another platform.

Where a field was derived rather than recorded directly, establish the rule or data source used to create it. Preserve the documentation or explanation relied upon so that another person can understand and review the interpretation.

Do not assume blank means none, zero means failure or a display name identifies a person. The system’s own definitions must come first.

Operational takeaway¶

Field definitions turn labels into evidence by establishing what each value actually represents, how it was created and what conclusions it can safely support.