User`s guide
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File Transfer Protocol (FTP)
A standard Internet protocol that specifies the simplest way to exchange files between computers 
on the Internet. 
HyperText Transfer Protocol (HTTP)
An application protocol in the TCP/IP suite that defines the rules for transferring files (text, 
graphic images, sound, video, and other multimedia files) on the World Wide web (WWW).
HyperText Transfer Protocol over Secure Socket Layer (HTTPS)
A secure message-oriented communications protocol designed for use in conjunction with 
HTTP. HTTPS encrypts and decrypts user page requests as well as the pages that are returned 
by the web server. HTTPS uses the Secure Socket Layer (SSL) as a sublayer.
Internet Control Message Protocol (ICMP)
A message control and error-reporting protocol between a host server and a gateway to the 
Internet. ICMP uses Internet Protocol (IP) datagrams, but the messages are processed by the IP 
software and are not directly apparent to the application user.
Internet Group Management Protocol (IGMP)
Internet Group Management Protocol (IGMP) provides a way for an Internet computer to report 
its multicast group membership to adjacent routers. Multicasting allows one computer on the 
Internet to send content to multiple other computers that have identified themselves as interested 
in receiving the originating computer's content. Multicasting can be used for such applications 
as updating the address books of mobile computer users in the field, sending out company 
newsletters to a distribution list, and “broadcasting” high-bandwidth programs of streaming 
media to an audience that has “tuned in” by setting up a multicast group membership.
IP filtering
A network configuration that can be enabled to establish rules allowing devices to permit or deny 
specific IP addresses, networks, or devices from connection access. Also known as access 
control list.
Java applet interface
An optional Java-applet based web interface for configuring, monitoring, and administering Digi 
Connect products.
MAC address
A unique network identifier. All network devices are required to have their own unique MAC 
address. The MAC address is on a sticker on your Digi device. The number is displayed as 12 
hexadecimal digits, usually starting with 00:40:9D. 
Management Information Base (MIB)
A formal description of a set of network objects that can be managed using the Simple Network 
Management Protocol (SNMP). 
modem emulation
A serial port configuration where the port acts as a modem. The Digi device emulates modem 
responses to a serial device and seamlessly sends and receives data over an Ethernet network 
instead of a Public Switched Telephone Network (PSTN). The advantage for a user is the ability 
to retain legacy software applications without modification and use a less expensive Ethernet 
network in place of public telephone lines. Also known as pseudo-modem or pmodem.










