3com 2816 ユーザーガイド
Physical Features
9
supports automatic MDI/MDI-X detection and can be
connected to a 10BASE-T, 100BASE-TX, or a
1000BASE-T device.
connected to a 10BASE-T, 100BASE-TX, or a
1000BASE-T device.
Ports 1 to 16 (2816-SFP) or ports 1 to 24 (2824-SFP) are
auto-negotiating: their speed and duplex mode (half
duplex or full duplex for 10BASE-T and 100BASE-TX, full
duplex only for 1000BASE-T) are automatically
determined by the capabilities of the connected device.
auto-negotiating: their speed and duplex mode (half
duplex or full duplex for 10BASE-T and 100BASE-TX, full
duplex only for 1000BASE-T) are automatically
determined by the capabilities of the connected device.
CAUTION: The Switch supports full duplex
auto-negotiation. If auto-negotiation is disabled for
1000BASE-T, then the Switch uses the forced-mode
default of 100 full duplex mode. If the connected device
does not support auto-negotiation, 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 auto-negotiation (and that
you ensure that auto-negotiation is enabled, if it is a
configurable option).
auto-negotiation. If auto-negotiation is disabled for
1000BASE-T, then the Switch uses the forced-mode
default of 100 full duplex mode. If the connected device
does not support auto-negotiation, 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 auto-negotiation (and that
you ensure that auto-negotiation is enabled, if it is a
configurable option).
(2) SFP Ports
The Small Form Factor Pluggable (SFP) ports are
numbered 13 to 16. If an SFP transceiver (purchased
separately) is installed in a slot and is active, the
associated RJ-45 port of the same number is disabled.
numbered 13 to 16. If an SFP transceiver (purchased
separately) is installed in a slot and is active, the
associated RJ-45 port of the same number is disabled.
The four 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
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.
Switch and remote 1000 Mbps workgroups or to create
a high-capacity aggregated link backbone connection.
SFP ports are numbered 13 to 16 (2816-SFP) and 21 to
24 (2824-SFP) 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.
24 (2824-SFP) 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 Status LEDs
The following table lists LEDs visible on the front of the
Switch, and how to read their status according to color.
Switch, and how to read their status according to color.
Table 1 10BASE-T/100BASE-TX Ports
Status
Meaning
Green
The link is operating at 1000 Mbps.
Yellow
The link is operating at 10 or 100 Mbps.
Flashing
Green
Green
Packets are being received or transmitted on the
port at 1000 Mbps.
port at 1000 Mbps.
Flashing
Yellow
Yellow
Packets are being received or transmitted on the
port at 10 or 100 Mbps.
port at 10 or 100 Mbps.