Iv security measures and enforcement an overview a

IV. Security Measures and Enforcement: An Overview
A comprehensive security system should include biometric security measures, nonbiometric
In-Class Activity
Ask students to gather information about two famous security threats that the world has
witnessed. Were these threats intentional or unintentional? Have students discuss how these
threats were controlled.
Discussion Question
In the context of computer network security, identify some measures that can protect against
data theft and data loss. Do technological advancements act as a boon or bane in protecting
data?

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security measures, physical security measures, access controls, virtual private networks, data
encryption, e-commerce transaction security measures, and Computer Emergency Response
Team.
A. Biometric Security Measures
Biometric security measures use a physiological element that is unique to a person and
cannot be stolen lost, copied, or passed on to others. The following list describes some
biometric devices:
 Facial recognition
 Fingerprints
 Hand geometry
 Iris analysis
 Palm prints
 Retinal scanning
 Signature analysis
 Vein analysis
 Voice recognition
Some drawbacks of biometrics are high cost, users’ reluctance, and complex installation.
However, with improvements being made to address these drawbacks, biometrics can be a
viable alternative to traditional security measures.
B. Nonbiometric Security Measures
The three main biometric measures are called back modems, firewalls, and intrusion detection
systems.
Callback Modems
A callback modem verifies whether a user’s access is valid by logging the user off (after
he or she attempts to connect to the network) and then calling the user back at a
predetermined number.
Firewalls
A firewall is a combination of hardware and software that acts as a filter or barrier between
a private network and external computers or networks, including the Internet. An effective
firewall should protect data going from the network as well as data coming into the
network. Information being transmitted is stored in what’s called a packet , and after

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examining a packet, a firewall can take one of the following actions:
 Reject the incoming packet
 Send a warning to the network administrator
 Send a message to the packet’s sender that the attempt failed
 Allow the packet to enter (or leave) the private network
The main types of firewalls are packet-filtering firewalls, application-filtering firewalls,
and proxy servers. Packet-filtering firewalls control data traffic by configuring a router to
examine packets passing into and out of the network. These firewalls record all incoming
connections, and packets that are rejected might be a warning sign of an unauthorized
attempt. Packet-filtering firewalls are somewhat inefficient, however, because they have to
examine packets one by one, and they might be difficult to install.