Multitech MultiVOIP MVPGK1 Gatekeepers, Руководство пользователя по оборудованию

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MultiVOIP Gatekeeper User Guide
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Chapter 4 - PCI NIC Board
suitable for the quality of the telephone line linkage between them. The parameters to be settled
between the two modems include best baud rate, compression method, and error correction method.
When the two modems have tested the phoneline quality and settled on the combination of shared
options and parameters which will provide the best data communication over the connecting phone
line, then you are given the “Connect” message which signals the end of the intermodem negotiation
and the beginning of your intended communication with the remote computer.
Auto-negotiation between devices within an Ethernet LAN is similar in concept, but much briefer. The
two devices involved in the auto-negotiation will be the EN10100PCI Adapter serving your station and
the hub through which it is connected into the LAN. The options to be negotiated between the
EN10100PCI and its supporting hub include Ethernet type (100BASE-TX Fast Ethernet or 10BASE-T
Ethernet) and duplex mode (half-duplex, being one-way-at-a-time, or full duplex, being simultaneous
transmit-and-receive). Startup communication between the two devices occurs when both devices are
power-on, the cable connection between them is good, and the Network Operating System software is
running. As soon as those conditions are satisfied, the preparatory process of auto-negotiation between
the EN10100PCI and its supporting hub proceeds automatically. If the hub has auto-negotiation
functionality, then it and the EN10100PCI exchange a series of messages in which each device signals
its capabilities and listens for corresponding information about the other. The auto-negotiation process
requires only a few milliseconds, and the two devices select the best communication parameters
supported by both devices. If the hub does not have auto-engotiation functionality, then its monotone
(single capability) message will be recognized by the EN10100PCI’s auto-negotiation facility, and the
EN10100PCI will simply switch to one of its own capabilities which matches that of the hub.
When the preparatory procedure of auto-negotiation is completed, then the line is ready and will
provide a data channel which is optimal for the two devices. The line will remain ready without further
auto-negotiation action until the linkage is broken. Auto-negotiation then reoccurs at any time that the
linkage is restored, again making the line ready for optimal data communications.
About PCI Bus
Your EN10100PCI Adapter delivers outstanding performance by fully exploiting the advanced features of
your computer’s PCI bus. EN10100PCI Adapters utilize the Bus Master Mode of the PCI bus, enableing
direct transfers of Ethernet packet content between computer memory and the adapter’s controller,
thus minimizing network demand on the CPU. The adapter’s controller function provides the additional
benefit of reduced command processing overhead. The working relationship between a EN10100PCI
adapter and main memory working in Bus Master mode is powered by the Bridge/Memory Controller of
the PCI bus. This reduces the CPU role in network operations, thus freeing the CPU to service other
tasks, with resulting improvement in overall computing (multitasking) performance. At the same time, it
produces superior network throughput by reducing latency (waiting for CPU service) during
transmissions and receptions.
Features
Designed for versatility and performance, the EN10100PCI Adapter provides the following features:
· Operates in a PCI Bus Master slot of a Pentium computer, independent of CPU speed.
· PCI Bus Master memory access, for high throughput and low CPU demand.
· 32-bit Intelligent Ethernet controller.
· Complies with IEEE 802.3 100Base-TX and 10Base-T Ethernet standards.
· Plug and Play installation.
· RJ-45 connector for network cable connection.
· 100Mbps Fast Ethernet or 10Mbps Ethernet data transfer, selected via auto-negotiation.