3Com 3C17203 - SuperStack 3 Switch 4400, Руководство по внедрению

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18 C
HAPTER
1: S
WITCH
F
EATURES
O
VERVIEW
■
Disconnect Unauthorized Device (DUD) — disables a port if an
unauthorized device transmits data on it.
■
Switch Management Login — user name and password information is
stored in a database on a RADIUS server in your network. Log in
attempts to the Switch are remotely authenticated by the RADIUS
server.
For more information about how the port security features work, see
Chapter 11 “Making Your Network Secure” .
Power Management Power Management is the supply and control of power to connected
Ethernet devices. Power Management provides two benefits:
■
Cabling needs are reduced — Power over Ethernet (802.3af)
compliant devices need only an Ethernet cable.
■
Reliability is increased — As the power is supplied over the Ethernet
cable it can be backed up by redundant and uninterruptible power
supplies.
Power Management is only available on the Switch 4400 PWR
(3C17205).
For more information about power management, see Chapter 12
“Power Management and Control” .
Aggregated Links Aggregated links are connections that allow devices to communicate
using up to four links in parallel. Aggregated links provide two benefits:
■
They can potentially double, triple or quadruple the bandwidth of a
connection.
■
They can provide redundancy — if one link is broken, the other links
share the traffic for that link.
For more information about aggregated links, see Chapter 2
“Optimizing Bandwidth” .
Auto-negotiation Auto-negotiation allows ports to auto-negotiate port speed,
duplex-mode (only at 10 Mbps and 100 Mbps) and flow control. When
auto-negotiation is enabled (default), a port “advertises” its maximum