Dell 3348 Switch User Manual


 
Configuring Switch Information 211
Disable—Disables auto negotiation on the port. This is the default value.
Current Auto Negotiation—Indicates the Auto Negotiation operational status.
Back Pressure—Enables Back Pressure mode on the device. Back Pressure mode is
used with Half Duplex mode to disable ports from receiving messages. When Back
Pressure is enabled, Head-of-Line blocking is not operational, even if it is set to enable.
The possible field values are:
Enable—Enables back pressure on the port.
Disable—Disable back pressure on the port. This is the default value.
Current Back Pressure—Indicates the back pressure operational status.
Flow Control—Indicates if Flow Control is enabled on the port. Flow control is
enabled if the device is in Duplex mode. In addition, when Flow Control is enabled,
Head-of-Line is disabled on the selected port. When Flow Control is enabled, Head-
of-Line blocking is not operational, even if it is set to enable. The possible field values
are:
Enable—Indicates that Flow Control is enabled on the device.
Disable—Indicates that Flow Control is disabled on the device. This is the
default value.
Current Flow Control—Indicates the Flow Control operational status.
Auto-negotiation—Enables auto negotiation of Flow Control on the port.
Tx Only—Enables auto negotiation for egress ports.
Rx Only —Enables auto negotiation for ingress ports.
MDI/MDIX—Allows the device to decipher between crossed and uncrossed cables.
Hubs and switches are deliberately wired the opposite way end stations are wired, so
that when a hub or switch is connected to an end station, a straight through Ethernet
cable can be used, and the pairs match up properly. When two hubs/switches are
connected to each other, or two end stations are connected to each other, a crossover
cable is used to make sure that the correct pairs are connected. The standard cable
wirings are:
Media Dependent Interface with Crossover (MDIX) for hubs and switches
Media Dependent Interface (MDI) for end stations
NOTE: Auto MDIX does not operate on FE ports when auto negotiation is disabled.