Netgear XCM8806 Chassis User Manual - Page 391

Disadvantages of Web-Based Authentication

Page 391 highlights

NETGEAR 8800 User Manual The DHCP allocation for network login has a short time duration of 10 seconds and is intended to perform web-based network login only. As soon as the client is authenticated, it is deprived of this address. The client must obtain an operational address from another DHCP server in the network. DHCP is not required for 802.1x, because 802.1x uses only Layer 2 frames (EAPOL) or MAC-based network login. URL redirection (applicable to web-based mode only) is a mechanism to redirect any HTTP request to the base URL of the authenticator when the port is in unauthenticated mode. In other words, when the user tries to log in to the network using the browser, the user is first redirected to the network login page. Only after a successful login is the user connected to the network. URL redirection requires that the switch is configured with a DNS client. Web-based, MAC-based, and 802.1x authentication each have advantages and disadvantages, as summarized next. Advantages of Web-Based Authentication: • Works with any operating system that is capable of obtaining an IP address using DHCP. There is no need for special client side software; only a web browser is needed. Disadvantages of Web-Based Authentication: • The login process involves manipulation of IP addresses and must be done outside the scope of a normal computer login process. It is not tied to a Windows login. The client must bring up a login page and initiate a login. • Supplicants cannot be re-authenticated transparently. They cannot be re-authenticated from the authenticator side. • This method is not as effective in maintaining privacy protection. Advantages of MAC-Based Authentication: • Works with any operating system or network enabled device. • Works silently. The user, client, or device does not know that it gets authenticated. • Ease of management. A set of devices can easily be grouped by the vendor part of the MAC address. Disadvantages of MAC-Based Authentication: • There is no re-authentication mechanism. The FDB aging timer determines the logout. • Security is based on the MAC address of the client, so the network is more vulnerable to spoofing attacks. Advantages of 802.1x Authentication: • In cases where the 802.1x is natively supported, login and authentication happens transparently. • Authentication happens at Layer 2. It does not involve getting a temporary IP address and subsequent release of the address to obtain a permanent IP address. • Allows for periodic, transparent re-authentication of supplicants. Chapter 16. Network Login | 391

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Chapter 16.
Network Login
|
391
NETGEAR 8800 User Manual
The DHCP allocation for network login has a short time duration of 10 seconds and is
intended to perform web-based network login only. As soon as the client is authenticated, it is
deprived of this address. The client must obtain an operational address from another DHCP
server in the network. DHCP is not required for 802.1x, because 802.1x uses only Layer 2
frames (EAPOL) or MAC-based network login.
URL redirection (applicable to web-based mode only) is a mechanism to redirect any HTTP
request to the base URL of the authenticator when the port is in unauthenticated mode. In
other words, when the user tries to log in to the network using the browser, the user is first
redirected to the network login page. Only after a successful login is the user connected to
the network. URL redirection requires that the switch is configured with a DNS client.
Web-based, MAC-based, and 802.1x authentication each have advantages and
disadvantages, as summarized next.
Advantages of Web-Based Authentication:
Works with any operating system that is capable of obtaining an IP address using DHCP.
There is no need for special client side software; only a web browser is needed.
Disadvantages of Web-Based Authentication:
The login process involves manipulation of IP addresses and must be done outside the
scope of a normal computer login process. It is not tied to a Windows login. The client
must bring up a login page and initiate a login.
Supplicants cannot be re-authenticated transparently. They cannot be re-authenticated
from the authenticator side.
This method is not as effective in maintaining privacy protection.
Advantages of MAC-Based Authentication:
Works with any operating system or network enabled device.
Works silently. The user, client, or device does not know that it gets authenticated.
Ease of management. A set of devices can easily be grouped by the vendor part of the
MAC address.
Disadvantages of MAC-Based Authentication:
There is no re-authentication mechanism. The FDB aging timer determines the logout.
Security is based on the MAC address of the client, so the network is more vulnerable to
spoofing attacks.
Advantages of 802.1x Authentication:
In cases where the 802.1x is natively supported, login and authentication happens
transparently.
Authentication happens at Layer 2. It does not involve getting a temporary IP address
and subsequent release of the address to obtain a permanent IP address.
Allows for periodic, transparent re-authentication of supplicants.