Chapter 6:
Virtual Private Networking Using SSL
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New Template Style Guide Reference Manual
takes precedence over a policy applied to all IP addresses. If two or more IP address ranges
are configured, then the smallest address range takes precedence. Hostnames are treated
the same as individual IP addresses.
Network resources are prioritized just like other address ranges. However, the prioritization is
based on the individual address or address range, not the entire network resource.
For example, let’s assume the following global policy configuration:
•
Policy 1: A Deny rule has been configured to block all services to the IP address range
10.0.0.0 – 10.0.0.255.
•
Policy 2: A Deny rule has been configured to block FTP access to 10.0.1.2 – 10.0.1.10.
•
Policy 3: A Permit rule has been configured to allow FTP access to the predefined
network resource, FTP Servers. The FTP Servers network resource includes the
following addresses: 10.0.0.5 – 10.0.0.20 and ftp.company.com, which resolves to
10.0.1.3.
Assuming that no conflicting user or group policies have been configured, if a user attempted
to access:
•
An FTP server at 10.0.0.1, the user would be blocked by Policy 1.
•
An FTP server at 10.0.1.5, the user would be blocked by Policy 2.
•
An FTP server at 10.0.0.10, the user would be granted access by Policy 3. The IP
address range 10.0.0.5 - 10.0.0.20 is more specific than the IP address range defined in
Policy 1.
•
An FTP server at ftp.company.com, the user would be granted access by Policy 3. A
single host name is more specific than the IP address range configured in Policy 2.
Note:
The user would not be able to access ftp.company.com using its IP
address 10.0.1.3. The <Product Name> policy engine does not
perform reverse DNS lookups.