Glossary
8-34
8
Appendix
O
OS/2
A family of multitasking operating systems developed by IBM for Intel x86-based
computers. OS/2 provides a graphical user interface similar to Windows, as well as a
command line interface similar to DOS. Add-ons to OS/2 enable it to run DOS and
Windows applications.
P
Packet signature
Encrypted signatures used when exchanging data packets to guarantee that a packet
really came from the computer that it claims to have come from. Packet signature is
designed to prevent packet forgery and unauthorized Supervisor access to a
NetWare server.
PASV mode
Passive FTP mode. An alternative mode for initiating FTP connections. In this mode,
data transfer is initiated by the FTP client, rather than the FTP server. As corporate
firewalls generally reject external data requests from FTP servers, the PASV mode
may allow FTP to be used with NAT (Network Address Translation) and with clients
behind firewalls, depending on the environment. The PASV mode also ensures that
all data flow requests come from inside the network where the client is located.
Pause
You can insert a pause within a telephone number or at the end of a telephone
number. A pause is also sometimes required to connect to an outside line, or for
overseas fax transmissions to certain countries.
Pause Time
The default settings are two seconds if a pause is inserted within the telephone
number (may vary depending on your location), and 10 seconds if a pause is added
to the end of the telephone number. Only the length of pauses inside a telephone
number, and not those at the end, can be changed.
PBX
Private Branch eXchange. An in-house telephone switching system that
interconnects telephone extensions to each other, as well as to the external
telephone network. A PBX controls the flow of telephone traffic through instruments,
such as paging systems, and automatic callback and dialing.
PCL
Printer Control Language. A protocol originally designed by Hewlett-Packard,
enabling PCs to communicate with printers. PCL has become a standard for laser
and ink jet printers, and is now supported by most printer manufacturers.