Choosing A High Speed Flow Control Mode - Nortel BayStack 410 24T Using Manual

Using the BayStack 410-24T 10BASE-T Switch
Table 3-20. High Speed Flow Control Configuration Screen Fields
Field
Flow Control
Preferred Phy
Active Phy

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 BayStack 410-24T switch 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 gigabit MDA port and its link partner to send
flow-control pause frames to each other. When a pause frame is received (by
either the gigabit MDA port or its link partner), the port suspends transmission of
frames for a number of slot times specified in the control frame or until a
pause-release control frame is received. Both devices on the link must support this
mode when it is selected.
3-56
Description
Allows you to control traffic and avoid congestion on the gigabit MDA port. Two
modes are available (see
page 3-56 for details about the two modes). Autonegotiation must be disabled
for this port when using this feature.
Default Value Disabled
Range Disabled, Symmetric, Asymmetric
Note:
The following two fields only appear when a (single MAC) MDA with a
separate redundant Phy port is installed.
Allows you to choose the preferred Phy port; the other Phy port reverts to
backup.
Default Value Right
Range Right, Left
Indicates the operational Phy port.
Default Value: None
Range: None, Right, Left
"Choosing a High Speed Flow Control
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