3Com 1000, Руководство пользователя

Страница: 58 / 152

4-14 C
HAPTER
4: M
ANAGING
T
HE
S
WITCH
1000
Duplex Mode Half Duplex / Full Duplex / Unit
Default This field allows you to specify the duplex
mode of the port:
■
Full Duplex — Full duplex allows frames to be
transmitted and received simultaneously and, in
effect, doubles the potential throughput of a link.
In addition, full duplex also supports
100BASE-FX cable runs of up to 2km. You should
only enable full duplex on a point to point link
between the Switch and another device with full
duplex support.
Full duplex is not supported on the Transceiver
Module port.
■
Half Duplex — You should use half duplex if the
port connects to a shared Ethernet or Fast Ether-
net LAN segment, or if the device at the other
end of a point-to-point link does not support full
duplex.
■
Unit Default — The duplex mode of the port is
defined by the Duplex Mode field in the Unit
Setup screen. This is the default setting.
VLAN Configuration Mode Port / AutoSelect /
Unit Default This field allows you to specify how the
port is placed in a VLAN:
■
Port
— The port uses Port VLAN Mode, which
means that the port is manually placed in the
required VLAN.
■
AutoSelect — The port uses AutoSelect VLAN
Mode, which means that the port is automatically
placed in the required VLAN by referring to a
VLAN Server database in 3Com’s Transcend Enter-
prise Manager software.
■
Unit Default — The port uses Port VLAN Mode or
AutoSelect VLAN Mode depending on the con-
tents of the VLAN Configuration Mode field in
the Unit Setup screen. This is the default setting.
For more information, refer to “Using AutoSelect
VLAN Mode” on page 5-3 .
Broadcast Storm Control The Switch automati-
cally creates an alarm on each of its ports to moni-
tor the level of broadcast traffic on each port. The
Broadcast Storm Control fields allow you to specify
thresholds for the level of broadcast traffic on a
port, and specify an action to take place if the
threshold is exceeded.
Rising Threshold% This field allows you to specify
the percentage of broadcast traffic on the current
port which triggers the alarm for the port. The
default is 20%.
Falling Threshold% This field allows you to specify
the percentage of broadcast traffic on the current
port required to reset the alarm for the port. The
falling threshold prevents the rising threshold
events being triggered continuously. The default is
10%.