Types of Threats

Threats to the network security are an emergent problem for the individual as well as organizations in the whole world, and the threats become worse and multiply day by day. Computer networks are necessary for everyday activities and both the Individuals and organizations depend on their computers and networks.

Intrusion to these computers by an illegal person can result in network breakdown and loss of data and works. Attacks on a network can be disturbing, which result in a loss of time and money due to damage or theft of significant information.

The Intruders can enter into the network through software vulnerabilities, through guess someone's username and password and hardware attacks. An intruder is an individual commonly called hacker or software that enters a computer without authorization. When intruder (hacker) successfully gains access to the network, four types of threats may happen:-

Loss of Data and manipulation

When hacker successfully enters to someone computer, he destroys or alters data records. Examples sending a virus that reformats a computer's hard drive and breaking into a records system to change information.

Information Theft

In this case when intruder gain access to the computer which obtains confidential information. The intruder used this Information for different purposes and he also sold this information.

Identity Theft

The individual usually obtains the personal document on their personal computer.  The intruder stole this personal information. Using this information, an intruder can get legal documents, make an unauthorized purchase and apply for credit.

Disruption of service

If the intruder can't get in, then he tries to ensure that no one else can, either. This is the Dos (denial-of-service attack). This kind of threat does not try to get information directly, depending on which service crashes under the load, their effect can expose other resources that were previously protected.

Physical Security Threats

The physical security is another important aspect of network security. The aspects of physical security must be dealt with in an organizational policy. The physical security has four classes of physical threats are:

• Hardware threats– hardware threat is physical damage network devices, servers, and workstations.


• Electrical threats– This threat is about the input voltage, the voltage may be insufficient, voltage spikes, unconditioned power, and complete power loss


• Maintenance threats– This threat is about poor handling of electrical components, poor cabling and labeling and lack of spare parts.


• Environmental threats– Environment threat also important, the temperature too hot or too cold and humidity too wet or too dry are the environmental threats.

To Limit the physical damage to equipment, make a security plan is as follow:-

• Lockup equipment


• Prevent unauthorized access


• Maintain electronic logs of entry and exits


• Use security cameras

The figure below illustrates a general floor plan for a secure computer room for a network.