Configuring Ethernet Parameters; Auto-Negotiation; Full-Duplex/Half-Duplex; Speed - Avaya C360 Installation And Configuration Manual

Configuring Ethernet Parameters

Auto-Negotiation

Auto-Negotiation is a protocol that runs between two stations, two switches or a station and a
switch. When enabled, Auto-Negotiation negotiates port speed and duplex mode by detecting
the highest common denominator port connection for the endstations. For example, if one
workstation supports both 10 Mbps and 100 Mbps speed ports, while the other workstation only
supports 10 Mbps, then Auto-Negotiation sets the port speed to 10 Mbps.
For Gigabit ports, Auto-Negotiation determines the Flow Control configuration of the port.

Full-Duplex/Half-Duplex

Devices that support Full-Duplex can transmit and receive data simultaneously, as opposed to
half-duplex transmission where each device can only communicate in turn.
Full-Duplex provides higher throughput than half-duplex.

Speed

The IEEE defines three standard speeds for Ethernet: 10, 100 and 1000 Mbps (also known as
Ethernet, Fast Ethernet and Gigabit Ethernet respectively).

MDI/MDI-X Detection

Auto MDI/MDI-X (cross-over cable) detection allows use of both straight and crossover cables
without the need to configure ports individually.

Flow Control

The process of adjusting the flow of data from one device to another to ensure that the receiving
device can handle all of the incoming data. This is particularly important where the sending
device is capable of sending data much faster than the receiving device can receive it.
There are many flow control mechanisms. One of the most common flow control protocols,
used in Ethernet full-duplex, is called xon-xoff. In this case, the receiving device sends a an xoff
message to the sending device when its buffer is full. The sending device then stops sending
data. When the receiving device is ready to receive more data, it sends an xon signal.
Ethernet
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