Alcatel-Lucent 6850-48 参照ガイド
IP Commands
page 32-20
OmniSwitch CLI Reference Guide
September 2009
ip directed-broadcast
Enables or disables IP directed broadcasts routed through the switch. An IP directed broadcast is an IP
datagram that has all zeros or all 1’s in the host portion of the destination address. The packet is sent to the
broadcast address of a subnet to which the sender is not directly attached.
datagram that has all zeros or all 1’s in the host portion of the destination address. The packet is sent to the
broadcast address of a subnet to which the sender is not directly attached.
ip directed-broadcast {on | off}
Syntax Definitions
N/A
Defaults
The default value is off.
Platforms Supported
OmniSwitch 6400, 6850, 6855, 9000, 9000E
Usage Guidelines
Directed broadcasts are used in denial-of-service “smurf” attacks. In a smurf attack, a continuous stream of
ping requests are sent from a falsified source address to a directed broadcast address, resulting in a large
stream of replies, which can overload the host of the source address. By default, the switch drops directed
broadcasts. Typically, directed broadcasts should not be enabled.
ping requests are sent from a falsified source address to a directed broadcast address, resulting in a large
stream of replies, which can overload the host of the source address. By default, the switch drops directed
broadcasts. Typically, directed broadcasts should not be enabled.
Examples
-> ip directed-broadcast off
Release History
Release 6.1; command was introduced.
Related Commands
MIB Objects
alaIpDirectedBroadcast
Displays the status and configuration of IP interfaces.
Displays the IP Forwarding table.
Displays IP configuration parameters.