Snom ONE IP, Техническое руководство

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by the Internet’s DNS system like traditional Web site domains. The goal of the
ENUM standard is to provide a single number to replace the multiple numbers
and addresses for an individual’s home phone, business phone, fax, cell phone,
and e-mail.
FTP (File Transfer Protocol)
A standard Internet protocol used to upload and download files between com-
puters that are connected to the Internet. FTP uses the Internet’s TCP/IP proto-
cols as does HTTP, which transfers displayable Web pages and related files, and
SMTP, which transfers e-mail.
FQDN (fully-qualified domain name)
The complete domain name for a specific computer, or host, on the Internet. The
FQDN consists of three parts: the hostname, the domain name, and the top-level
domain (e.g., www.webopedia.com and sip.itsp.com).
FxO (Foreign exchange Office) interface
A device usually found on the customer end (e.g., a plug on a phone or fax
machine, or the plug on an analog phone system) that receives the analog line.
Because the FXO port is attached to a device, such as a fax or phone, the device is
often called an FXO device. FXO and FXS are always paired. See “FXS.”
FxS (Foreign exchange Subscriber) interface
A device usually located on the telephony company’s property that sends power
through a channel to a phone on the other end. It provides battery power, a dial
tone, and a ring. By necessity, it must connect to an FXO device. See “FXO.”
GSM (Global System for Mobile communication)
A wireless telephone standard in Europe and other parts of the world. GSM
uses a variation of time division multiple access (TDMA), which is the most
widely used of the three digital wireless telephony technologies (TDMA, GSM,
and CDMA). GSM digitizes and compresses data, then sends it down a channel
with two other streams of user data, each in its own time slot. It operates at either
the 900 MHz or 1800 MHz frequency band.