Address Range

An address range is a set of numerically contiguous IP addresses. Networks and subnetworks are typically identified by a name for the range of IP addresses. You use the beginning and ending addresses to identify an IP address range.

You can set up an address object to represent an address range in SunScreen. The figure below shows examples of ranges of addresses for the Corporate and Sales networks. For example, the Corporate address object is defined as a range of addresses from 172.16.3.2 to 172.16.3.255. You could then establish access or encryption rules for hosts on the Corporate network by indicating the rule applies to the Corporate address object.

SunScreen 3.2 supports four syntaxes for ranges:

• a.b.c.d e.f.g.h

• a.b.c.d - e.f.g.h (same as above, spaces optional around '-')

• a.b.c.d/m.n.o.p (m.n.o.p is the network+subnet mask)

• a.b.c.d/# (# is CIDR, number of network+subnet bits)

In the figure below, for example, the following are all the same:

• 172.16.3.0 172.16.3.255

• 172.16.3.0-172.16.3.255

• 172.16.3.0 - 172.16.3.255

• 172.16.3.0/255.255.255.0

• 172.16.3.0/24

The values in parentheses in the figure (255.255.255.0) represent a netmask.

Figure 4-2 Range of IP Addresses