Users Guide

Table Of Contents
352 Authentication, Authorization, and Accounting
Figure 9-14. Customized Captive Portal Welcome Screen
How Does Captive Portal Work?
When a port is enabled for CP, all the traffic coming onto the port from the
unverified clients is dropped except for the ARP, DHCP, NetBIOS, and DNS
packets. These packets are forwarded by the switch so that the unverified
clients can get an IP address and are able to resolve host or domain names. If
an unverified client opens a web browser and tries to connect to the network,
CP redirects all the HTTP/HTTPS traffic from the unverified client to the
authenticating server on the switch. If the network administrator has
configured an additional web server port, packets with this destination TCP
port number are also forwarded to the authenticating server. A CP web page is
sent back to the unverified client. If the verification mode for the CP
associated with the port is Guest, the client can be verified without providing
authentication information. If the verification mode is Local or RADIUS, the
client must provide credentials that are compared against the information in
the Local or RADIUS client database. After the user successfully provides the
required information, the CP feature grants access to the network.
What Captive Portal Pages Can Be Customized?
The following three CP pages can be customized:
Authentication Page —This page displays when a client attempts to
connect to the network. The images, text, and colors that display on this
page can be customized.