LevelOne GEL-2870, Руководство по установке, Страница: 24 / 74

C
HAPTER
1
| Introduction
Description of Hardware
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S
WITCH
A
RCHITECTURE
The switch employs a wire-speed, non-blocking switching fabric. This permits
simultaneous wire-speed transport of multiple packets at low latency on all
ports. The switch also features full-duplex capability on all ports, which
effectively doubles the bandwidth of each connection.
This switch uses store-and-forward switching to ensure maximum data integrity.
With store-and-forward switching, the entire packet must be received into a
buffer and checked for validity before being forwarded. This prevents errors
from being propagated throughout the network.
N
ETWORK
M
ANAGEMENT
O
PTIONS
With a comprehensive array of LEDs, the switch provides “at a glance”
monitoring of network and port status. The switch can be managed over the
network with a web browser or Telnet application, or via a direct connection to
the console port. The switch includes a built-in network management agent that
allows it to be managed in-band using SNMP or RMON (Groups 1, 2, 3, 9)
protocols. It also has an RS-232 serial port (DB-9 connector) on the front panel
for out-of-band management. A PC may be connected to this port for
configuration and monitoring out-of-band via a null-modem serial cable.
For a detailed description of the management features, refer to the Management
Guide .
D
ESCRIPTION OF
H
ARDWARE
1000BASE-T P
ORTS
The switch contains 28 1000BASE-T RJ-45 ports. All RJ-45 ports support
automatic MDI/MDI-X operation, so you can use straight-through cables for all
network connections to PCs or servers, or to other switches or hubs. (See
“1000BASE-T Pin Assignments” on page 58 .)
Each of these ports support auto-negotiation, so the optimum transmission
mode (half or full duplex), and data rate (10, 100, or 1000 Mbps) can be
selected automatically
2 .
2. The 1000BASE-T standard does not support forced mode. Auto-negotiation must
always be used to establish a connection over any 1000BASE-T port or trunk.