Fax Header Bar
Definition
The line of text printed at the top of each received fax page under regulatory requirements (US FCC 47 CFR 68.318, UK Ofcom, EU Directive 2002/58/EC), carrying the sender CSID, transmission date-time, and page number.
- Contents
- Sender CSID, transmission date-time, page number
- US requirement
- FCC 47 CFR 68.318
- UK/EU basis
- Ofcom rules, EU Directive 2002/58/EC
- Location
- Top of each received fax page
Common questions
Why is the fax header bar useful as forensic evidence?+
Because the sender's fax machine automatically stamps its own identifier and the transmission time onto every page under regulatory requirement, the header bar can corroborate or contradict a claimed sender, date, or time independent of the document's actual content.
Can a fax header bar be forged or altered?+
Yes; because the CSID is configured by the machine's owner rather than independently verified by the network, it can be set to a false value, and the printed header can also be physically altered on paper, so examiners treat it as corroborating evidence rather than a self-authenticating record.
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