Operation Manual – IP Addressing and IP PerformanceH3C S5500-EI Series Ethernet Switches Chapter 2 IP Performance Configuration2-1Chapter 2 IP Performance ConfigurationWhen configuring IP performance, go to these sections for information you areinterested in:z IP Performance Overviewz Enabling Reception and Forwarding of Directed Broadcasts to a DirectlyConnected Networkz Configuring TCP Attributesz Configuring ICMP to Send Error Packetsz Displaying and Maintaining IP Performance2.1 IP Performance OverviewIn some network environments, you need to adjust the IP parameters to achieve bestnetwork performance. IP performance configuration includes:z Enabling the device to receive and forward directed broadcastsz Configuring the maximum TCP segment size (MSS) of the interfacez Configuring TCP timersz Configuring the TCP buffer sizez Enabling ICMP error packets sending2.2 Enabling Reception and Forwarding of DirectedBroadcasts to a Directly Connected NetworkDirected broadcasts refer to broadcast packets sent to a specific network. In thedestination IP address of a directed broadcast, the network ID is a network-specificnumber and the host ID is all ones. Enabling the device to receive and forward directedbroadcasts to a directly connected network will give hackers an opportunity to attackthe network. Therefore, the device is disabled from receiving and forwarding directedbroadcasts by default. You should however enable the feature when:z Using the UDP Helper function to convert broadcasts to unicasts and forwardthem to a specified server.z Using the Wake on LAN function to forward directed broadcasts to a PC on theremote network.2.2.1 Enabling Reception of Directed Broadcasts to a Directly ConnectedNetworkIf a device is enabled to receive directed broadcasts, the device will determine whetherto forward them according to the configuration on the outgoing interface.
