Dell PowerConnect 6248 User's Guide - Page 195

Table 6-37. Denial of Service Configuration Commands CLI Command dos-control sipdip dos-control tcpflag dos-control tcpfrag ip icmp echo-reply ip icmp error-interval ip icmp unreachables ip icmp redirects ipv6 icmp error-internal ipv6 unreachables show dos-control Description Enables Source IP Address = Destination IP Address (SIP=DIP) Denial of Service protection. Enables TCP Flag Denial of Service protections. Enables TCP Fragment Denial of Service protection. Enables or disables the generation of ICMP Echo Reply messages. Limits the rate at which IPv4 ICMP error messages are sent. Enables the generation of ICMP Destination Unreachable messages. Enables the generation of ICMP Redirect messages. Limits the rate at which ICMPv6 error messages are sent. Enables the generation of ICMPv6 Destination Unreachable messages. Displays Denial of Service configuration information. Captive Portal The Captive Portal (CP) feature allows you to block clients directly connected to the switch from accessing the network until user verification has been established. You can configure CP verification to allow access for both guest and authenticated users. Authenticated users must be validated against a database of authorized Captive Portal users before access is granted. The database can be stored locally on the switch or on a RADIUS server. When a port is enabled for Captive Portal, all the traffic coming onto the port from the unauthenticated clients are dropped except for the ARP, DHCP, DNS and NETBIOS packets. These packets are allowed to be forwarded by the switch so that the unauthenticated clients can get an IP address and be able to resolve the hostname or domain names. Data traffic from authenticated clients goes through as expected. If an unauthenticated client opens a web browser and tries to connect to network, the Captive Portal redirects all the HTTP/HTTPS traffic from unauthenticated clients to the authenticating server on the switch. A Captive portal web page is sent back to the unauthenticated client and the client can authenticate and based upon the authentication the client is given access to the port. NOTE: For information about the CLI commands you use to view and configure Captive Portal settings, refer to the Captive Portal Commands chapter in the CLI Reference Guide. The Captive Portal folder contains links to the following pages that help you view and configure system Captive Portal settings: • CP Global Configuration • CP Configuration • CP Web Customization • Local User Configuring System Information 195