Nomadix Access Gateway User Manual page 77

A G
CCESS ATEWAY
1. Select the External Web Server
After enabling the External Web Server you must enter a Secret Key. The Secret Key
ensures that the response the Access Gateway gets from the EWS is valid.
Enter the
2. Secret Key
the same secret key).
DNS must be configured if you want to enter meaningful URLs instead of numeric
IP addresses into any of the Access Gateway's configuration screens (for
example, the External login page URL in the following step).
Enter a valid
3.
Configure the
4.
See
signing.
Click on the
5.
to reset all the values to their previous state (making changes to the EWS settings does not
require a system reboot).
Redirection Parameter Signing
External Web Server (EWS) and Internal Web Server (IWS) Portal Page Parameters can be
digitally signed, preventing malicious subscribers from intercepting, forging and replaying
URL redirection strings used by the NSE and EWS or IWS Portal Page to validate subscriber
access. This capability eliminates a vulnerability that was previously exploited to gain
unauthorized Internet access at charge-for-use sites.
The signing feature can create a cryptographically strong signature that protects the sensitive
portions of a URL redirection string (i.e., NSE ID, MAC address of the subscriber, etc), while
letting the EWS/Portal Page verify that the URL string has not been tampered or forged by the
subscriber.
System Administration
.
(The Access Gateway and the external authorization server must use
External login page URL
Parameter Signing
Redirection Parameter Signing
button to save your changes, or click on the
Submit
.
options.
for more information about parameter
button if you want
Reset
65