Components of PSF printing

The two main components of PSF printing are data streams and resources. PSF communicates with the printer to manage and control the data transmitted to the printers.

Data streams

The data streams placed on the JES spool are:

Line data

Application output prepared for printing that is not composed into pages. To print line data on page printers, a page definition is required to provide the data placement and presentation information. For information about printing line data, see Line data.

XML data

Data that is identified as using Extensible Markup Language (XML) standards from the World Wide Web Consortium. XML does not describe data placement or presentation information. For printing on page printers, a page definition is required to provide the data placement and presentation information. The XML data processed by PSF can be encoded in EBCDIC, ASCII, UTF-8 or UTF-16. For more information about printing XML data, see XML data.

MO:DCA-P

Data that is already composed into pages, including data placement and presentation information (such as which font to use). PSF supports MO:DCA Presentation Interchange Set (IS) data streams, including MO:DCA IS/3. For information about printing MO:DCA-P data, see MO:DCA-P data.

IPDS

Data sent to the printer that contains both the data to be printed and the controls defining how the data is to be presented. For more information about IPDS, see Communication between PSF and the printer.

Mixed-mode

A combination of line data and MO:DCA-P data. If MO:DCA-P data is already formatted into pages, it cannot be printed on the same logical page as line data. When PSF finds the beginning or the ending of a MO:DCA-P data page, it starts a new page.

Resources

PSF uses a combination of these resources to print AFP data:

Fonts

Graphic characters of a given style that are used to present text. AFP fonts that PSF supports can be one of these types:

FOCA

Fonts defined by the Font Object Content Architecture (FOCA). A FOCA font is a paired character set and code page that can be used together to print a string of text characters.

TrueType and OpenType

Unicode-enabled fonts not defined by FOCA. TrueType and OpenType fonts consist of tables that identify the formatting information used to support Unicode encoding.

Form definitions

Information that defines the presentation of the logical page on the physical medium, such as where the page is placed on the medium and whether the data is printed on one or both sides of the paper.

Object containers

Object envelopes that contain certain types of non-OCA data objects.

Overlays

Predefined data objects that can contain text, images, graphics, bar codes, object containers, and page segments and can be merged with application data for presentation. Overlays are often used as electronic forms.

Page definitions

Information used to format line data and XML data into AFP pages.

Page segments

Predefined data objects that can contain text, image, graphics, and bar code data objects that can be presented at any location on a page and are included during printing. Examples of items that can be page segments include logos, signatures, bar charts, and engineering drawings.

Bar codes, graphics, images, and text

BCOCA, GOCA, IOCA, and PTOCA objects stored as resources.

For more information about resources, see Using resources.

Communication between PSF and the printer

PSF converts MO:DCA-P, line data, and XML data from the JES spool into IPDS. IPDS contains information about a printer, such as the characteristics of the printer, its resolution, what resources it has, whether it has sufficient memory, and whether it receives and prints a job. PSF communicates back and forth with the printer through IPDS to successfully manage and control the data transmitted to the printers.