2. Equipment console management
A lot of equipment, including routers, program controlled switches, UPS,
LAN switches and various network devices, provide consoles to allow
administrators more convenient management. Under usual circumstances,
administrators can do detailed configuration by connecting the consoles of these
equipment to the COM ports of the terminals or mainframes.
However, in many actual application environments, all the network
equipment is gathered in the company or even remote machine rooms.
Geographically restricted, administrators may feel inconvenient in managing this
equipment. Although some equipment may be managed through Telnet, many
non-network equipment usually does not provide remote configuration functions.
Serial port equip ment server is an ideal solution for all the difficult problems in
console management.
In actual applications, one serial port equipment server may be installed in
places where equipment is centralized for connection with the consoles of the
equipment. Serial port equipment servers can provide TCP/IP connection through
their own interfaces, identifying an independent TCP number for each of its serial
ports. Remote mainframes can visit all the equipment consoles connected to the
serial port equipment server through Telnet (through different TCP ports). By
establishing a transparent channel between the consoles of the equipment and the
application programs, the serial port equipment server can allow the
administrators to achieve the same effect of local equipment console operation
when operating remote equipment consoles, providing an ideal solution for the
above- mentioned challenge they face.
This application does not need any driving program in the mainframe. Only
the Telnet client program is necessary. It is also called Rtelnet, or Reverse Telnet.
3. Visiting equipment networks
In automatic industrial fields, there are thousands of sensors, detectors, PLC,
card readers and other devices, interconnecting into a control network as a tool of
inter-system data management. The most commonly used communication
protocols for the connection of this equipment are RS-232 and RS-422/485. More
and more extensively employed in the industry during the past several years,
network frameworks like Ethernet/Internet are replacing traditional serial port
communication to become the mainframe of the automatic system
communication. With this trend, highly mature open network technologies,
represented by TCP/IP, are gradually being used in various automatic systems for
the connection and control of all equipment. Each serial port device has the
requirement of networking through TCP/IP protocols. Therefore, the
administrators may visit this equipment just the way they visit common IP
equipment.
Serial port equipment server provides an ideal solution for the above problem.
Under this application mode, each device connected with the serial port
equipment server is assigned a TCP or UDP port number. TCP mode is similar to
equipment Console management in actual practice. Their difference lies in that
the equipment Console management mode connects through Telnet, while
equipment management mode through SOCKET written by clients themselves.
Due to its non-connectivity, the UDP mode can enable multiple mainframes to
control a single port to achieve the effect of multi- mainframe data backup.
