Computer Forensics Basics Technology

What is Computer Forensics?
There a number of slightly varying definitions around. However, generally, computer forensics is considered to be the use of analytical and investigative techniques to identify, collect, examine and preserve evidence/information which is magnetically stored or encoded.

What is the objective of this?
Usually to provide digital evidence of a specific or general activity.

To what ends?
A forensic investigation can be initiated for a variety of reasons. The most high profile are usually with respect to criminal investigation, or civil litigation, but digital forensic techniques can be of value in a wide variety of situations, including perhaps, simply re-tracking steps taken when data has been lost.

What are the common scenarios?
Wide and varied! Examples include:
- Employee internet abuse (common, but decreasing)
- Unauthorized disclosure of corporate information and data (accidental and intentional)
- Industrial espionage
- Damage assessment (following an incident)
- Criminal fraud and deception cases
- More general criminal cases (many criminals simply store information on computers, intentionally or unwittingly)
- and countless others!

How is a computer forensic investigation approached?
It's a detailed science. However, very broadly, the main phases are sometimes considered to be: secure the subject system (from tampering during the operation); take a copy of hard drive (if applicable); identify and recovery all files (including those deleted); access/copy hidden, protected and temporary files; study 'special' areas on the drive (eg: residue from previously deleted files); investigate data/settings from installed applications/programs; assess the system as a whole, including its structure; consider general factors relating to the users activity; create detailed report. Throughout the investigation, it is important to stress that a full audit log of your activities should be maintained.

Is there anything that should NOT be done during an investigation?
Definitely. However, these tend to be related to the nature of the computer system being investigated. Typically though, it is important to avoid changing date/time stamps (of files for example) or changing data itself. The same applies to the overwriting of unallocated space (which can happen on re-boot for example). 'Study don't change' is a useful catch-phrase.

I am interested in a career in this field. Where do I start?
This is a common question, with many answers. Perhaps a good starting point however is to read the specific section of our Forum: "Digital Forensics: Getting Started". This includes hundreds of posts on this issue.

What about training?
Again, there is a specific area of the Forum dedicated to education and training. In addition, we are currently building an entire section comprising first party reviews of formal courses (see left hand panel). Finally, although designed largely for practitioners, the Computer Forensics Toolkit is increasingly being used as a training resource (see top right).

Source: www.computerforensicsworld.com