Control Connection; Data Connection; Ftp Login - HP Jetdirect 250M User Manual

Once an FTP session is opened, it remains active until either
the client closes the connection or the data and control
connections are idle for a time that exceeds the idle timeout
period (default is 270 seconds). The idle timeout can be set
through various TCP/IP configuration tools, such as
BOOTP/TFTP, Telnet, printer's control panel (see
Configuration), the embedded web server (see
Embedded Web Server), or management software.

Control Connection

Using standard FTP, a control connection is opened by the
client to the FTP server on the HP Jetdirect print server. FTP
control connections are used to exchange commands between
the client and the FTP server. The HP Jetdirect print server
supports up to four control connections (or FTP sessions)
simultaneously. If the number of allowed connections is
exceeded, a message indicating that service is not available will
be displayed.
FTP control connections use TCP port 21.

Data Connection

A second connection, a data connection, is created each time a
file is transferred between the client and the FTP server. The
client controls the creation of a data connection by issuing the
commands that require a data connection (such as FTP ls,
dir or put commands).
Although the ls and dir commands are always accepted, the
HP Jetdirect FTP server supports a single data connection for
printing at a time.
The transmission mode for an FTP data connection with the
HP Jetdirect print server is always in stream mode, which
marks the end-of-file by closing the data connection.
Once a data connection is established, the file transfer type
(ASCII or binary) can be specified. Clients may attempt to
autonegotiate a transfer type, and the default transfer type
depends on the client system (for example, Windows NT may
default to ASCII, while UNIX may default to binary). To
specify the transfer type, enter the bin or ascii command at
the FTP prompt.

FTP Login

To start an FTP session, enter the following command from a
MS-DOS or UNIX command prompt:
ftp <IP address>
where <IP address> is the valid IP address or node name
configured for the HP Jetdirect print server. See
Example
TCP/IP
Using the
FTP Login