ZyXEL Communications 56K manual Pstn, Quiet, Ram, Rfc, Rom

	User's Guide for ZyXEL Omni 56K USB Modem
Protocol	A “language” for communicating on a network. Protocols are sets of standards or rules used
	to define, format, and transmit data across a network. There are many different protocols
	used on networks. For example, most web pages are transmitted using the HTTP protocol.
Proxy Server	A server that performs network operations in lieu of other systems on the network. Proxy
	Servers are most often used as part of a firewall to mask the identity of users inside a
	corporate network yet still provide access to the Internet. When a user connects to a proxy
	server, via a web browser or other networked application, he submits commands to the
	proxy server. The server then submits those same commands to the Internet, yet without
	revealing any information about the system that originally requested the information. Proxy
	servers are an ideal way to also have all users on a corporate network channel through one
	point for all external communications. Proxy servers can be configured to block certain
	kinds of connections and stop some hacks.
PSTN	Public Switched Telephone Network was put into place many years ago as a voice
	telephone call-switching system. The system transmits voice calls as analog signals across
	copper twisted cables from homes and businesses to neighborhood COs (central offices);
	this is often called the local loop. The PSTN is a circuit-switched system, meaning that an
	end-to-end private circuit is established between caller and called.
Public Domain	A special form of distributing software. Public domain software authors make no claim to
	commercialize their rights.
Public Key	System of encrypting electronic files using a key pair. The key pair contains a public key
Encryption	used during encryption, and a corresponding private key used during decryption.
QUIET	A state in the voice mode of ZyXEL modems. Quiet is detected after a long pause in voice
	data.
RAM	Random Access Memory – working memory. The modem uses it among many other uses
	to store information on sent, but not yet acknowledged data.
Redundancy	Extra data that does not generate additional information.
Remote Location	The modem at the other end of the line (the one you are calling or that is calling).
Reset	Return a device into a defined base status.
Retrain	The re-initialization process a modem is doing with the remote modem when the receiving
	condition becomes bad.
RFC	An RFC (Request for Comments) is an Internet formal document or standard that is the
	result of committee drafting and subsequent review by interested parties. Some RFCs are
	informational in nature. Of those that are intended to become Internet standards, the final
	version of the RFC becomes the standard and no further comments or changes are
	permitted. Change can occur, however, through subsequent RFCs.
ROM	Read Only Memory. The ROM holds the system software and the profiles and settings of
	the modem (refer to EEPROM).
Router	A device that connects two networks together. Routers monitor, direct, and filter
	information that passes between these networks. Because of their location, routers are a
	good place to install traffic or mail filters. Routers are also prone to attacks because they
	contain a great deal of information about a network.
RS	Abbreviation of recommended standard.

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