Logical Objects; Address Book; Ip Address - D-Link DFL-1600 User Manual

8

Logical Objects

Logical objects are basic network elements defined in the firewall, referring
to the entities needed to be protected and also the untrusted resources and
applications that should be monitored by the security policies.
8.1

Address Book

Like the contacts book which records people's name with one's phone
number and email address, the address book in a Firewall is a list of
symbolic names associated with various types of addresses, including IP
addresses and ethernet MAC addresses. These items are fundamental
elements heavily used in the firewall's configuration, such as specifying
filtering fields for security policies. Therefore, choosing a descriptive and
easily remembered name for each address item will greatly ease
administration work. The administrator can use the names in each
configuration task instead of filling in addresses every time, and in case of
any modification to an address, only one point in the address book need to
be changed.
8.1.1

IP address

To enable every entity receiving and sending data from or to a TCP/IP
network, a network layer (OSI layer 3) IP address is required to associate
with each point between the network entity and the physical link, that is an
interface. In other words, each interface has a unique IP address in the
39