Zultys MX250, Руководство по оборудованию

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MX250 Hardware Manual
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 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 Protocol (IP). A network layer protocol that sends datagram packets between Internet
nodes. IP is a connectionless protocol, implying that there is no continuing connection between
communicating endpoints. IP provides addressing, type-of-service (ToS) specification, security,
fragmentation and reassembly features. The most widely used IP version is Internet Protocol
Version 4 (IPv4). The ZIP 4x4 phone supports IP as defined in RFC 791.
Internet Protocol Version 6 (IPv6). The latest level of the IP that is included in many projects,
including the major computer operating systems. The most obvious improvement in IPv6 over
IPv4 is the lengthening of IP addresses from 32 bits to 128 bits. All servers that support IPv6 will
also support Internet Protocol Version 4.
Intranet. A restricted-access network that works like the Web, but isn't on it. Usually owned and
managed by a corporation, an intranet enables a company to share its resources with its
employees without making available confidential information to everyone with Internet access.
IP Address (version 4). A 32-bit number that identifies each sender or receiver of information sent
across the internet. An IP address has two parts: the network identifier and the identifier of a
specific device on the network. On the Internet itself – between the router that moves packets
between points along the route – only the network part of the address is examined.
IP Security (IPSec). Security standard produced by the Internet Engineering Task Force (IETF); a
protocol suite that provides all necessary elements for secure communications-authentication,
integrity, and confidentiality-and makes key exchange practical even in larger networks.
Jitter. Jitter is the deviation in some aspect of the pulses in a high-frequency digital signal or the
period frequency displacement of the signal from its ideal location. The MX250 utilizes Jitter
Buffers to compensate for jitter.