GE GFK-1852 - Manual (Page 22)

3-2 VersaMax Serial to Ethernet Adapter User's Manual – July 2000 GFK-1852
3
Port Number
Every TCP connection and every UDP datagram are defined by a destination IP
address and a port number. An IP address is necessary to address a device (host) on
the network. A port number is necessary to address an application or a channel on a
network host. The port number can be compared to an extension on a PBX
(telephone) system.
A Telnet application (login to a host with an ASCII terminal) is commonly assigned
TCP port number 23. More than one Telnet connection can be established to one host
using the Telnet port; however, the other peer IP address/port number combination
must be different.
In the VMSE (PassThru Firmware), a port number can be configured on the channel
(port). The VMSE uses this port number for outgoing messages and incoming
connections or UDP datagrams, which are addressed to its port number. Port 9999
(decimal) is used for remote configuration.