Network Basics
ITherm™ POSjet™ BANKjet™
Programmer's Guide
Ethernet Adapter
Page 32
Rev C
Apr-04
Protocols in the TCP/IP suite
Inside the TCP/IP protocol are additional standards that allow different types of devices to
interact. For example for file transfers, FTP or File Transfer Protocol is used. It has an
additional identification called the Port.
The following table identifies various protocols within the TCP/IP suite and the ports that they
use.
Protocol
Port
Description
DHCP
67
Used for automatic TCP/IP allocation
HTTP
80
Used on Internet WWW servers
TELNET
23
Used for terminal type access
FTP
21
Used to send or retrieve data
LPR
515
Used to send data to printers
Raw
9100
Used to send and receive data directly to a TCP/IP port
Automatic IP address allocation
It is possible to have the local network setup and have one device on the network assign an IP
address automatically. The TransAct print server supports DHCP (Dynamic Host Configuration
Protocol) for automatic IP address assignment. This requires that there be a DHCP server in the
local network to perform the assignment. This assignment process may have some
disadvantages in a POS network. It is difficult to assure that a given device is always assigned
the same address. For this reason, static IP addresses are generally manually assigned to devices.
Manual IP address allocation
Rather than allow DHCP to assign an IP address it is possible to assign an address manually. If
the IP address is assigned manually, it must follow the requirements of the rest of the network to
operate correctly.
The TransAct Ethernet adapter is easily configured to use manual address assignments. In the
POS environment, it is important to make sure that print data be sent to the correct printer. By
using manual IP address assignments, you can assure that the print data will always be sent to the
correct printer.
