Choosing A High Speed Flow Control Mode; Symmetric Mode - Nortel 325-24T Configuration Manual

114 Chapter 2 Using the console interface
Table 18 High Speed Flow Control Configuration screen fields (continued)
Field
Autonegotiation
Speed/Duplex
Flow Control

Choosing a high speed flow control mode

The high speed flow control feature allows you to control traffic and avoid
congestion on the Gigabit full-duplex link. If the receive port buffer becomes full,
the Ethernet Switch 425-24T issues a flow-control signal to the device at the other
end of the link to suspend transmission. When the receive buffer is no longer full,
the switch issues a signal to resume the transmission. You can choose Symmetric
or Asymmetric flow control mode.

Symmetric mode

This mode allows both the GBIC port and its link partner to send flow control
pause frames to each other.
320985-A Rev 01
Description
Indicates if the Autonegotiation has been enabled on the port. When enabled,
the port only advertises support for 1000 Mb/s operation, in full-duplex mode.
Default Value Enabled
Range Enabled, Disabled
Displays if a port is configured to support an Ethernet speed of 10 Mb/s or 100
Mb/s, in half- or full-duplex mode. This field is set (by default) to 1000 Mb/s,
full-duplex for Gigabit ports only.
Default 100Mbs/Half (when Autonegotiation is Disabled)
Range 10Mbs/Half, 10Mbs/Full, 100Mbs/Half, 100Mbs/Full
Indicates if the switch or unit has been configured to control traffic and avoid
congestion on the Gigabit MDA port. Two modes are available (see
a high speed flow control
Flow Control field cannot be configured unless you set the Autonegotiation field
value to Disabled.
Default Value Disabled
Range Disabled, Symmetric, Asymmetric
Note: All fields (except the Unit field) described in
read-only fields.
mode"," next, for details about the two modes). The
"Choosing
Table 18 are