LevelOne GSW-4876 - Manual (Page 57)

C HAPTER 4 | Configuring the Switch
Configuring Port Connections
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N OTE :
The 1000BASE-T standard does not support forced mode. Auto-
negotiation should always be used to establish a connection over any
1000BASE-T port or trunk. If not used, the success of the link process
cannot be guaranteed when connecting to other types of switches.
◆ Flow Control – Flow control can eliminate frame loss by “blocking”
traffic from end stations or segments connected directly to the switch
when its buffers fill. When enabled, back pressure is used for half-
duplex operation and IEEE 802.3-2005 (formally IEEE 802.3x) for full-
duplex operation. (Default: Disabled)
When auto-negotiation is used, this parameter indicates the flow
control capability advertised to the link partner. When the speed and
duplex mode are manually set, the Current Rx field indicates whether
pause frames are obeyed by this port, and the Current Tx field indicates
if pause frames are transmitted from this port.
Avoid using flow control on a port connected to a hub unless it is
actually required to solve a problem. Otherwise back pressure jamming
signals may degrade overall performance for the segment attached to
the hub.
◆ Maximum Frame Size – Sets the maximum transfer unit for traffic
crossing the switch. Packets exceeding the maximum frame size are
dropped. (Range: 1518-10056 bytes; Default: 10056 bytes)
◆ Excessive Collision Mode – Sets the response to take when excessive
transmit collisions are detected on a port.
■
Discard - Discards a frame after 16 collisions (default).
■
Restart - Restarts the backoff algorithm after 16 collisions.
◆ Power Control – Adjusts the power provided to ports based on the
length of the cable used to connect to other devices. Only sufficient
power is used to maintain connection requirements.
IEEE 802.3 defines the Ethernet standard and subsequent power
requirements based on cable connections operating at 100 meters.
Enabling power saving mode can significantly reduce power used for
cable lengths of 20 meters or less, and continue to ensure signal
integrity.
The following options are supported:
■
Disabled – All power savings mechanisms disabled (default).
■
Enabled – Both link up and link down power savings enabled.
■
ActiPHY – Link down power savings enabled.
■
PerfectReach – Link up power savings enabled.
W EB I NTERFACE
To configure port connection settings:
1.
Click Configuration, Ports.