Posts Tagged ‘network’

Internal Threats: Employees

Saturday, November 29th, 2008

We tend to think the security threats to a business originate outside the organization. In fact, company insiders pose serious security problems. Employees have access to previleged information, and in the presence of sloppy internal security procedures, they are often able to roam throughout an organization’s systems without leaving a trace.

Studies have found that user lack of knowledge is the single greatest cause of network security breaches. Many employees forget their passwords to access computer systems or allow co-workers to use them, which compromises the system.

Malicious intruders seeking system access sometimes trick employees into revealing their passwords by pretending to be legitimate members of the company in need of information. This practice is called social engineering

Both end users and information systems specialists are also a major source of errors introduced into information systems. End users introduce errors by entering faulty data or by not following the proper instructions for processing data and using computer equipment. Information systems specialists may create software errors as they design and develop new software or maintain existing programs. 

Signals: Digital vs. Analog

Monday, November 24th, 2008

The most basic distinction in communication networks is that between analog and digital signals. There are 2 ways to communicate a message: either an analog signal or a digital signal.

  • An analog signal is represented by a continuous waveform that passes through a communications medium and has been used for voice communication. The most common analog devices are the telephone hand set, the speaker on your computer, or your iPod earphone, all of which create analog wave forms that your ear can hear. Oh yes, your ear is an analog device also.
  • A digital signal is a discrete binary waveform, rather than a continuous, waveform. Digital signals communicate information as strings of two discrete states: one bit and zero bits, which are represented as on-off electrical pulses.

Computers use digital signals, so if you want to use the analog telephone system to send digital data, a device called a modem is required to translate digital signals into analog form. Modem stands for modulation/demodulation.

Now, I guess all of us understand why the heck we need the streamyx modem, huh? :)