3Com 3C16476CS User Manual page 10

10 C 1: I
HAPTER NTRODUCING THE
(half-duplex or full-duplex) are automatically
determined by the capabilities of the connected
device.
Each port also supports automatic MDI/MDI-X
detection and can be connected to either a 10BASE-T,
or a 100BASE-TX device.
CAUTION: The Switch supports full-duplex
autonegotiation. If the connected device does not
support autonegotiation, the Switch will operate in
half-duplex mode (even if the attached device is
operating in full-duplex mode).
In such a configuration, you may notice some
degradation of network performance. 3Com
recommends that you use devices that are capable of
autonegotiation (and that you ensure that
autonegotiation is enabled, if it is a configurable
option). (see "Troubleshooting"
(2) 10/100/1000BASE-T/SFP Ports
Ports 49 and 50 are combination Gigabit RJ-45 ports
with shared Small Form Factor Pluggable (SFP) trans-
ceiver slots. If an SFP transceiver (purchased sepa-
rately) is installed in a slot and is active, the associated
RJ-45 port of the same number is disabled.
The 1000BASE-T RJ-45 ports support automatic
MDI/MDI-X operation, so you can use
straight-through or crossover cables for all network
connections to workstations or servers, or to other
switches or hubs.
B S
ASELINE WITCH
on page 59).
The two SFP ports support fiber Gigabit Ethernet
short-wave (SX) and long-wave (LX) SFP transceivers
in any combination. This offers you the flexibility of
using SFP transceivers to provide connectivity
between the Switch and remote 1000 Mbps
workgroups or to create a high-capacity aggregated
link backbone connection.
SFP ports are numbered 49 and 50 on the Switch.
When an SFP port is active, it has priority over the
10/100/1000 port of the same number. The
corresponding 10/100/1000 port is disabled when an
SFP transceiver is plugged in.
(3) Link/Activity LEDs
The following tables describe the LEDs visible on the
front of the Switch, and how to read their status
according to color.
Table 4 10BASE-T/100BASE-TX Ports
Status Meaning
Green Link established, operating at 100 Mbps
Yellow Link established, operating at 10 Mbps
Flashing Green Packets are being received or
transmitted on the port at 100 Mbps