3Com Switch 8800 Advanced Software V5 Configuration Guide

24
IP PERFORMANCE CONFIGURATION
When configuring IP performance, go to these sections for information you are
interested in:
■ “IP Performance Overview” on page 235
■ “Enabling Forwarding of Directed Broadcasts to a Directly Connected
Network” on page 235
■ “Configuring TCP Attributes” on page 237
■ “Configuring TCP MSS for the Interface” on page 238
■ “Configuring ICMP Error Packet Sending” on page 238
■ “Displaying and Maintaining IP Performance” on page 240
IP Performance
Overview
In some network environments, you need to adjust the IP parameters to achieve
best network performance. IP performance configuration includes:
■ Enabling forwarding of directed broadcasts
■ Configuring TCP timers
■ Configuring the TCP buffer size
■ Configuring TCP MSS for the interface
■ Enabling ICMP error packet sending
Enabling Forwarding
of Directed Broadcasts
to a Directly
Connected Network
Directed broadcasts refer to broadcast packets sent to a specific network. In the
destination IP address of a directed broadcast, the network ID is a network-specific
number and the host ID is all ones.
Enabling the device to receive and forward directed broadcasts to a directly
connected network will give hackers an opportunity to attack the network.
Therefore, this feature is disabled by default.
When this feature is required in some network applications, you can configure the
device to forward directed broadcasts in system view or interface view. If you
disable this feature in system view, the switch discards directed broadcasts directly;
otherwise, the system determines whether to discard directed broadcasts
according to the interface configuration.
n
Switch 8800s can still receive broadcasts from a designated UDP port even if they
are disabled from receiving directed broadcasts.