Zultys MX250, Руководство по оборудованию

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A p p e n d i x B
Glossary
10/100Base-T.
A physical media that can operate as 10Base-T or 100Base-T.
10Base-T.
A physical media specified by the IEEE 802.3 standard for supporting Ethernet with a
maximum transmission rate of 10 Mb/s. 10BaseT consists of copper twisted-pair cable normally
used for wiring ordinary telephones. Ethernet is a common technology used for connecting
computers into a local area network (LAN).
100Base-T.
A local area network transmission standard that supports a data rate of 100 Mbps. Also
known as Fast Ethernet ; similar in function to 10BaseT.
Authorization.
The process of verifying the identity of a person or device. Authentication is
commonly performed through logon passwords; knowledge of the password is assumed to
guarantee that the user authenticity. Internet business and many other transactions may require
a more stringent authentication process, such as the use of digital certificates issued and verified
by a Certificate Authority as part of a public key infrastructure. Logically, authentication precedes
authorization, although they may often seem to be combined.
Bridge.
A device that connects network segments that use the same protocol, such as Ethernet. A
bridge forwards traffic between network segments on the basis of datalink layer information;
these segments would require a common network layer address.
Ethernet.
The most widely-installed local area network (LAN) technology. Originally developed
at the Xerox Corporation Palo Alto Research Center, Ethernet is specified in the IEEE 802.3
standard. Ethernet is a best-effort delivery system that uses CSMA/CD technology. Ethernet can
be run over a variety of physical media, including coaxial, twisted pair, and fiber optics.
Firewall.
A device, located at a network gateway server, that protects the resources of a private
network from external entities. Typically comprises a set of related programs or a dedicated
computer equipped with such security features as logging, reporting, alarms, and a control
mechanism.
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.
Frame Relay. A telecommunication service designed for cost-efficient data transmission of
intermittent traffic between local area networks (LANs) and between end-points in a wide area
network (WAN). Frame relay places data into in variable-size units called frames and speeds up
the overall data transmission by leaving all necessary error correction (data retransmission) up to
the end-points.