Zhone 2000 ユーザーガイド
G l o s s a r y
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MAC. Media Access Control. Lower of the two sub-layers of the data link
layer defined by the IEEE.
layer defined by the IEEE.
MAC address. Standardized data link layer address that is required for every
port or device that connects to a LAN. Other devices in the network use these
addresses to locate specific ports in the network and to create and update
routing tables and data structures. MAC addresses are six bytes long and are
IEEE-controlled. Also known as a hardware address, a MAC-layer address, or
a physical address.
port or device that connects to a LAN. Other devices in the network use these
addresses to locate specific ports in the network and to create and update
routing tables and data structures. MAC addresses are six bytes long and are
IEEE-controlled. Also known as a hardware address, a MAC-layer address, or
a physical address.
MPEG. Moving Pictures Expert Group.
Notified Entry. IP address of the MGCP Call Agent; controls the call setup
and teardown for all call features under MGCP.
and teardown for all call features under MGCP.
OSI Reference Model. Network architectural model developed by ISO and
ITU-T. The model consists of the following seven layers, each of which
specifies particular network functions.
ITU-T. The model consists of the following seven layers, each of which
specifies particular network functions.
The lowest layer is closest to the media technology and the highest layer is
closest to the user. The hardware and software implement the lower two
layers, while only the software implements the upper five layers.
closest to the user. The hardware and software implement the lower two
layers, while only the software implements the upper five layers.
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Physical layer
− the actual wires and connections in the network.
•
Data link layer
− responsible for physical addressing, network topology, error
notification and ordered delivery.
•
Network layer
− responsible for connectivity, path selection and routing.
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Transport layer
− responsible for network communication, virtual circuit
management, fault detection and flow control.
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Session layer
− manages sessions between applications.
•
Presentation layer
− responsible for data structures used by networked
applications.
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Application layer
− networked software applications such as e-mail, Telnet
and FTP.
Packet. Logical grouping of information that includes a header containing
control information and (usually) user data. Packets refer to network layer
units of data, with messages divided into several packets. Some networks use
fixed packet sizes; others use variable packet sizes. Packets typically have
standard header information that identifies the packet. In contrast, frames
contain only data; information about the frames transmits on the control plane.
control information and (usually) user data. Packets refer to network layer
units of data, with messages divided into several packets. Some networks use
fixed packet sizes; others use variable packet sizes. Packets typically have
standard header information that identifies the packet. In contrast, frames
contain only data; information about the frames transmits on the control plane.
The terms datagram, frame, message and segment describe logical information
groupings at various layers of the OSI reference model and in various
technology circles.
groupings at various layers of the OSI reference model and in various
technology circles.
PPP. Point-to-Point Protocol. a successor to SLIP that provides router-to-
router and host-to-network connections over synchronous and asynchronous
circuits.
router and host-to-network connections over synchronous and asynchronous
circuits.
Poisoned Reverse RIP. Feature to set routes learned on the same port as the
transmitted RIP message an infinite distance. Prevents the propagation of
routes from crashed routers through the network.
transmitted RIP message an infinite distance. Prevents the propagation of
routes from crashed routers through the network.