T.37
The ITU-T recommendation T.37 with the English title Procedures for the transfer of facsimile data via store-and-forward on the Internet (in German procedure for the transmission of fax data via store-and-forward on the Internet ) specifies a network protocol for the transmission of fax messages in a store-and-forward mode. The fax is transmitted in a TIFF file via email .
The recommendation was drawn up in 1998 and contains the status achieved at that time, so that not all performance features of fax machines in groups 3 and 4 that use the PSTN or ISDN instead of the Internet are taken into account. Together with Recommendation T.38, it is a basic recommendation for the transmission of faxes over the Internet. ITU-T is currently working on improvements, with the work program including:
- new modulation methods ,
- new coding methods like JPEG 2000 ,
- Color faxes.
Quality aspects are also an essential point of the work .
Use of the different TIFF formats in practice
TIFF-S or TIFF-F can be used for black and white documents and TIFF-J, TIFF-C, TIFF-L or TIFF-M for color documents. The majority of fax machines with T.37 had a black and white scanner. Since the majority of T.37-compatible fax machines are still equipped with a black and white printer, TIFF-S or TIFF-F is preferred for reasons of compatibility. These formats can be printed out by almost all T.37 fax machines.
Color TIFF plays a subordinate role, since implementation and support are costly. Furthermore, color Tiff could not establish itself on the market, as only a few manufacturers offer or have offered color TIFF in combination with T.37.
See also
Web links
Individual evidence
- ↑ http://www.itu.int/ITU-T/2001-2004/com16/sg16-q14.html work program of the ITU-T for the expansion of T.37 and T.38