B. Glossary
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File Transfer Protocol (FTP).
An application layer standard Internet protocol that uses the TCP/IP
protocols to exchange files between computers on the internet. Commonly used to transfer web
page files from the creator to a server or to download programs and other files from a computer
to other servers. Described by RFC 959.
Foreign Exchange Office (FXO).
An analog interface that connects to the Public Switched
Telephone Network (PSTN) central office and is the interface offered on a standard telephone.
Foreign Exchange Station (FXS).
An analog interface that connects directly to a standard
telephone and supplies ring, voltage, and dial tone.
FTP Account.
An SE system identifier that points to an FTP address.
Fully Qualified Domain Name (FQDN).
The portion of an Internet URL that identifies the server
program that an Internet request addresses. The FQDN includes the second-level domain name
(such as Zed-3.com) and any other levels (such as www.Zed-3.com).
Gateway.
A network point that serves as an entrance to another network. Computers that control
traffic within an enterprise’s network or at the local Internet Service Provider (ISP) are gateways.
IP datagrams are transferred from network to network through gateways until it reaches its final
destination. See Router.
Hub.
A hub network topology consists of a backbone (main circuit) to which a number of
outgoing lines can be attached, each providing at least one connection port for attaching devices.
As a network product, a hub may include a group of modem cards for dial-in users, a gateway
card for connections to a local area network, and a line connection.
Hypertext Transfer Protocol (HTTP).
An application layer protocol that defines a set of rules for
exchanging files (text, images, sound, video, and other multimedia files) on the Internet.
Described by RFC 2068.
Incoming call.
A call originated by a source that is external to the enterprise.
Internet.
A worldwide computer network system in which users at any one computer can, with
permission, exchange information from any other computer and sometimes talk directly to users
at other computers. also known as the “Net.” Originally designed by the Advanced Research
Projects Agency (ARPA) of the U.S. Defense Department in 1969 so that a communication signal
could withstand a nuclear war and serve military institutions worldwide. First known as the
ARPAnet, the internet has evolved into public, cooperative, and self-sustaining facility accessible
to billions of people worldwide.
Internet Control Message Protocol (ICMP).
A message control and error-reporting protocol
between a host server and an Internet gateway that enables hosts to send error or control
messages to other hosts. ICMP is an integral part of IP and must be implemented by every IP
module. Instances for sending an ICMP message include datagram processing errors, the
datagram cannot reach its destination, or when the gateway has insufficient buffering capacity to
forward a datagram. The ZIP 4x4 phone supports ICMP as documented in RFC 792.
Internet Engineering Task Force (IETF).
The organization that defines standard Internet operating
protocols such as TCP/IP. The IETF is supervised by the Internet Society Internet Architecture
Board (IAB). IETF members are drawn from the Internet Society's individual and organization
membership. Standards are expressed in the form of Requests for Comments (RFCs).
Internet Key Exchange (IKE).
The method for exchanging encryption and authentication keys
over an unsecured medium, such as the Internet.