Nokia IP60 - Security Appliance, Руководство пользователя

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Using NAT Rules
Chapter 12: Setting Your Security Policy 255
In this field… Do this…
My HotSpot is
password-
protected
Select this option to require users to enter their username and password
before accessing the Internet.
If this option is not selected, users will be required only to accept the terms of
use before accessing the network.
The
Allow a user to login from more than one computer at the same time
check box
appears.
Allow a user to
login from more
than one
computer at the
same time
Select this option to allow a single user to log on to My HotSpot from multiple
computers at the same time.
Use HTTPS Select this option to use HTTPS for Secure HotSpot.
After login,
redirect to URL
To redirect users to a specific URL after logging on to My HotSpot, select this
option and type the desired URL in the field provided.
For example, you can redirect authenticated
users to your company’s Web
site or a ―Welcome‖ page.
Using NAT Rules
Overview
In an IP network, each computer is assigned a unique IP address that defines both the host and the network.
A computer's IP address can be public and Internet-routable, or private and non-routable. Since IPv4, the
current version of IP, provides only 32 bits of address space, available public IP addresses are becoming
scarce, most having already been assigned. Internet Service Providers will usually allocate only one or a
few public IP addresses at a time, and while larger companies may purchase several such addresses for use,
purchasing addresses for every computer on the network is usually impossible.
Due to the lack of available public IP addresses, most computers in an organization are assigned private,
non-routable IP addresses. Even if more public IP addresses became available, changing the private IP
address of every machine in a large network to a public IP address would be an administrative nightmare,
being both labor intensive and time consuming. Therefore, organization's computers will most likely remain
with private, non-routable IP addresses, even though in most cases they require access to the Internet.
In addition to the issue of arranging Internet access for computers with non-routable IP addresses, IP
networks present a security challenge. Since making a network’s internal addresses public knowledge can