Computer Forensics - How Volatile Data is Analyzed

Computer forensics plays an important role in fightingTheoretically, it would be possible to freeze computer
terrorism and criminal activity. The fact is that badmemory by liquid nitrogen and this would significantly
guys use computers, internet and other modernincrease chances to recover the data but this
communication tools to communicate and to store theirapproach is not practical. Analysis of live volatile data in
plans. We would be naive if we would think that theya computer is essential for any serious forensic
can barely open Word or Excel. They are aware of allanalysis.
the risks and they protect themselves with modernThere are many open source and professional
encryption algorithms and general protective measures.commercial forensic tools that can make a snapshot
Fighting criminal activities is very different fromof crucial volatile data for later analysis. Such tools can
discovering occasional violations on companydiscover open ports, virtual disk drives, VPN
computers.connections and other resources not visible to the
Many traces can be hidden if the software used fornormal user. In some cases also the whole disk drive
criminal activity or otherwise unwanted is not presentor individual partition can be encrypted so it is important
on the computer disk and runs in the memory of theto make an image of it before the system is shut
computer. It is very easy to start some process anddown. Once all the data is safely stored it can be
then successfully cover all traces that were left behind.analyzed regardless of the state of the computer.
In such case analyzing disk data makes no senseA logical question would be, for example, what can be
because nothing suspicious could be discovered. Thedone to successful hide some processes running in the
only solution to this problem are tools that can protectcomputer memory? Theoretically, it would be possible
volatile data like live memory.to eliminate traces from the memory when the
The static analysis of computer data (i.e. the analysisprocess is not active or when it waits for some input.
of a hard disk removed from the computer) is usuallyBut even for such approaches there are some
not enough because many advanced techniques cansolutions. It is possible to create memory snapshots at
be used to erase all traces from file systems and theperiodic intervals and sooner or later the secret
only relevant data remains only in memory.process will show itself.