# Protecting Data at Risk of Unintentional Electromagnetic Emanation: TEMPEST Profiling
## 3 Sources of Electromagnetic Leakage
### Scanners  
Scanners transfer information by scanning documents into searchable PDF, BMP, GIF, or JPEG formats and sending the scanned image to pre-programmed destinations such as a printer, editing software application, or email. A scanner uses a light-sensitive sensor to read the content of a document. The document is placed, scanning begins, a light source illuminates the document, a sensor detects the reflected light, and the light pattern is converted into digital information. The scanning function is based on the quantum nature of light and the photoelectric effect on the metals it hits. When light with energy above the threshold hits the metal, the number of emitted electrons is proportional to the intensity of the light beam, and the kinetic energy of the emitted electrons is proportional to the frequency of the light [35].  
There are different types of document scanners on the market. Drum scanners are primarily used in the publishing industry because they print high-resolution images; flatbed scanners scan documents placed on a flat glass surface; portable scanners scan text-based documents; handheld scanners are designed to scan text documents by swiping the scanner over the text or images; and paper scanners scan text and images by simply holding and dragging the scanner across the page. All-in-one scanners are usually designed to combine multiple functions (printing, copying, and scanning) into one device. The market also offers different types of scanners protected against unwanted EM emanations. Europetemest offers eight Modulus TEMPEST scanners based on EPSON, HP, and Avision scanners [68]. OSPL [65] produces four scanners based on the HP Scanjet Pro 2500. All OSPL scanners are equipped with a high-speed DB9 cable and a TEMPEST filtered AC input with 100-230 VAC, 50/60 Hz operation, and a C/w 1.8 m shielded power cable with country-specific plug. Siltec provides SDIP Level A scanners based on A4, A3, and A0 Avision scanners [67]. C2 offers two Modulus T-scanners: a Flatbed/ADF scanner and a Flatbed/ADF network scanner [69] (Table 4.).  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Manufacturer** & **Scanner** & **Description** \\ \hline \multirow{4}{*}{C2} & Modulus T Scanner-N & TEMPEST network flatbed/ADF scanner. \\  & & Fulfills Level A, B, and C requirements. \\ \cline{2-3}  & Modulus T Scanner & TEMPEST flatbed/ADF scanner. \\  & & Fulfills Level A, B, and C requirements. \\ \hline \multirow{4}{*}{Eurotempest} & DS50000N-A & Based on Epson Workforce DS-50000N A3 scanner. \\  & & Fulfills Level B requirements. \\ \cline{2-3}  & DS60000n-A & Based on the Epson Workforce DS-60000N A3 scanner. \\ \cline{2-3}  & DS60000n-A & Fullfills Level A requirements. \\ \cline{2-3}  & DS6500-A & Based on the Epson Workforce DS-6500 A3 scanner. \\ \cline{2-3}  & & Fulfills Level A requirements. \\ \hline \hline \end{tabular}
\end{table}
Table 4: TEMPEST scanners.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Manufacturer** & **Printer** & **Description** \\ \hline \multirow{4}{*}{OSPL} & TP 454n-A and -B & Color A4 laser printers. Based on HP Laser Jet M454n. \\  & & Fulfills Level A and B requirements. \\ \cline{2-3}  & TP 150a-A and -B & Color A4 laser printer engines. Based on HP Laser Jet \\  & & 150a. Fulfills Level A and B requirements. \\ \hline \multirow{2}{*}{Siltec} & TEMPEST HP & HP-based A4, A3, and A0 printers. \\  & & Fulfills Level A, B, and C requirements. \\ \hline \hline \end{tabular}
\end{table}
Table 3: _Cont._