Computer forensics or digital forensics is a term in computer science to acquire authorized proof found in digital media or computers storage. With digital forensic investigation, the investigator can discover what happened to the digital media such as emails, hard disk, logs, computer system, and the network itself. In many case, forensic investigation can produce how the crime may happened and the way we will defend ourselves in opposition to it subsequent time.
Some explanation why we have to conduct a forensic investigation: 1. To assemble evidences so that it may be used in courtroom to unravel authorized cases. 2. To analyze our network energy, and to fill the safety hole with patches and fixes. 3. To get better deleted information or any recordsdata within the occasion of hardware or software failure
In computer forensics, a very powerful things that must be remembered when conducting the investigation are:
1. The original proof should not be altered in anyways, and to do conduct the method, forensic investigator must make a bit-stream image. Bit-stream image is a bit by bit copy of the unique storage medium and actual copy of the unique media. The difference between a bit-stream image and regular copy of the unique storage is bit-stream image is the slack space within the storage. You’ll not discover any slack space information on a duplicate media.
2. All forensic processes should follow the authorized legal guidelines in corresponding nation where the crimes happened. Every country has totally different regulation suit in IT field. Some take IT guidelines very severely, for instance: United Kingdom, Australia.
3. All forensic processes can solely be performed after the investigator has the search warrant.
Forensic investigators would usually trying on the timeline of how the crimes occurred in well timed manner. With that, we are able to produce the crime scene about how, when, what and why crimes might happened. In a big company, it’s recommended to create a Digital Forensic Group or First Responder Group, in order that the corporate may still protect the evidence till the forensic investigator come to the crime scene.
First Response rules are: 1. Not at all ought to anyone, with the exception of Forensic Analyst, to make any makes an attempt to recover data from any computer system or machine that holds electronic information. 2. Any try to retrieve the info by particular person mentioned in number 1, needs to be avoided because it might compromise the integrity of the evidence, in which became inadmissible in authorized court.
Based on that guidelines, it has already explained the important roles of getting a First Responder Group in a company. The unqualified individual can solely secure the perimeter in order that nobody can touch the crime scene till Forensic Analyst has come (This can be executed by taking photo of the crime scene. They will additionally make notes in regards to the scene and ontario who have been present at that time.
Steps must be taken when a digital crimes happenred in a professional manner: 1. Safe the crime scene till the forensic analyst arrive.
2. Forensic Analyst should request for the search warrant from native authorities or company’s management.
3. Forensic Analyst make take a picture of the crime scene in case of if there isn’t a any images has been taken.
4. If the computer continues to be powered on, don’t turned off the computer. Instead, used a forensic instruments akin to Helix to get some information that can solely be found when the computer continues to be powered on, similar to knowledge on RAM, and registries. Such instruments has it’s particular perform as to not write something back to the system so the integrity keep intake.
5. As soon as all live evidence is collected, Forensic Analyst cant turned off the computer and take harddisk back to forensic lab.
6. All of the evidences have to be documented, through which chain of custody is used. Chain of Custody hold information on the evidence, akin to: who has the proof for the final time.
7. Securing the proof have to be accompanied by legal officer akin to police as a formality.
8. Back within the lab, Forensic Analyst take the evidence to create bit-stream image, as authentic evidence must not be used. Normally, Forensic Analyst will create 2-5 bit-stream image in case 1 image is corrupted. After all Chain of Custody nonetheless used on this state of affairs to keep data of the evidence.
9. Hash of the original evidence and bit-stream image is created. This acts as a proof that authentic proof and the bit-stream image is the precise copy. So any alteration on the bit image will lead to different hash, which makes the evidences found grow to be inadmissible in court.
10. Forensic Analyst begins to find evidence in the bit-stream image by rigorously trying on the corresponding location will depend on what sort of crime has happened. For instance: Momentary Internet Information, Slack Area, Deleted File, Steganography files.