3Com 1000 - Manual (Page 19)

Unit Overview — Front 1-11
10BASE-T Ports
The Switch has 12 or 24 10BASE-T RJ45 ports con-
figured as MDIX (cross-over), which provide a full
10Mbps bandwidth to attached endstations. The
maximum segment length is 100m (328ft) over cat-
egory 3, 4, or 5 UTP cable.
As these ports are configured as MDIX (cross-over),
you need to use a cross-over cable to connect to
devices whose ports are MDIX-only. Most of the
10BASE-T ports in 3Com devices are MDIX-only.
100BASE-TX Port
The Switch has a single Fast Ethernet 100BASE-TX
RJ45 port configured as MDIX (cross-over), which
provides a 100Mbps connection to, for example, a
local server. The maximum segment length is 100m
(328ft) over category 5 UTP or STP cable.
As this port is configured as MDIX (cross-over), you
need to use a cross-over cable to connect to devices
whose ports are MDIX-only. Most of the
100BASE-TX ports in 3Com devices are MDIX-only.
LEDs
The table below describes the LED behavior on the
Switch. For more details about corrective action in
the event of a problem, refer to
“LEDs” on page
C-1 .
LED Color Indicates
TCVR Yellow Port 1 is a Transceiver Module fitted to the
rear of the unit.
Port Status LEDs
Packet Yellow Frames are being transmitted/received on the
port.
Status Green Link is present; port is enabled.
Green flashing Link is present; port is disabled.
Off Link is not present.
Plug-in Module Status LEDs
Packet Yellow Frames are being transmitted/received on the
Plug-in Module port.
Status Green Link is present; port is enabled.
Green flashing Link is present; port is disabled.
Green flashing
(long on, short
off) Refer to the “SuperStack II Switch ATM
OC-3c Module User Guide”.
Yellow Plug-in Module has failed its Power On Self
Test (if the MGMT LED is flashing yellow), or
the agent software of the Plug-in Module is
not installed correctly.
Yellow flashing Plug-in Module is not recognized.
Off Link is not present or Plug-in Module is not
installed in the Switch.
Unit Status LEDs
Power Green Switch is powered-up.
MGMT Green Switch is operating normally.
Green flashing Switch or Plug-in Module is either down-
loading software or initializing (which
includes a Power On Self Test).
Yellow Switch has failed its Power On Self Test.
Yellow flashing Plug-in Module has failed its Power On Self
Test.