Part 3 - The Preservation Phase of Investigation

Video Activity

This lesson covers the preservation phase of investigation. This must take place quickly to make sure evidence of preserved accurately. Investigators must take careful and accurate notes and record information such as times and actions taken and be sure to initial and sign off on everything.

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Time
7 hours 56 minutes
Difficulty
Advanced
CEU/CPE
7
Video Description

This lesson covers the preservation phase of investigation. This must take place quickly to make sure evidence of preserved accurately. Investigators must take careful and accurate notes and record information such as times and actions taken and be sure to initial and sign off on everything.

Video Transcription
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>> Moving on from the preparation phase,
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we go into the preservation phase.
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The first part of the preservation phase
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is that when encountering system,
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investigators must perform a rapid assessment of
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activity to ensure the preservation of any evidence.
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What that means is being able to
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look at a system and being able to
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determine if something is
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happening on that machine that is essentially
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going to change its state and damage
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any type of evidence that's going to hurt,
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and not just on the system,
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but maybe in the room where you find the system.
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Having that situational awareness
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of not just the machine,
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but your entire surroundings is going to aid
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you and being able to preserve all of that evidence.
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One of the first things that
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the investigator is going to want to do
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>> as part of that preservation process is to take notes.
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>> The note-taking essentially relates to
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what happened during the investigation.
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Notes are going to be very important,
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especially if you have to be in court.
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Oftentimes, a defense attorney
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will not necessarily attack the evidence per say,
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and they're going to attack the investigator,
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which would be you.
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Any little thing that they can find that you did
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wrong during your investigation,
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they're going to try and pick that
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apart and destroy your case.
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That's why it is of great importance that
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you record in detail every action that
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you take from the time that you
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become aware of the incident to the time you
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complete your central investigation on your notes.
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Here are some key note-taking points.
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The first thing that you're going to
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want to do is write in ink.
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Obviously, writing in pencil
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would subject your notes to change,
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writing in ink essentially makes them permanent.
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Then you would want to put your name and
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organization on the first line on the top of the page.
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The location of where the incident
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occurred to the smallest details.
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Not just the address of 123 main street,
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but if you have a suite number and office number,
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a desk number, down to that very small granular detail.
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You'll want to list any individuals
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who were present at the time of you
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acquiring that data or responding to the incident.
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Law enforcement investigations,
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they generally have a crime scene tape up,
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and anyone who comes in and out of the crime scene,
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their name must be written down on that log.
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On from that, we have the initialing
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each page and putting a number on each page.
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Then we want to cross out any mistakes that
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we make on our notes and all initial above them.
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We must include any diagrams and photographs that we
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make in our notes or reference
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them and make them available.
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At the end of the notes,
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we would include the statement,
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"nothing follows," and then we
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detail any and all actions that we take.
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Something as simple as arriving on
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the scene and securing the scene,
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that should appear in your notes.
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Then, very granular details about
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the operating system to include
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any information that we return from the OS,
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from any commands that we enter.
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If we find any media laying around per say,
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we find a thumb drive which we are going to get
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into later in the hands-on portion,
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we have to write the granular detail.
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If I found a gray SanDisk cruzer or 2.0
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gigabyte thumb drive
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>> with serial number 1234 on the back.
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>> Lastly, we're going to want to include
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a known good local time
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and annotate the source of where we obtained that.
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That known good local time will help us to normalize
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all the times that we find
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throughout our investigation to that one time.
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Often, systems may not be set to the appropriate time.
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If you have a suspect who was particularly savvy,
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they may cry and finagle the settings of
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the clock in order to help
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obfuscate some of their activities.
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So including a known good local time and
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annotating that on your notes is of key importance.
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Here's an example of the notes.
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As you can see,
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at the top of the page,
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I have the title of investigator notes.
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We have our Case 1234.
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If you are working,
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particularly in an incident response office,
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you may have an incident response number so that
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the case number may replace
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that incident response number.
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The investigator's names,
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I put my name there.
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Your organization that you're
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doing this forensic investigation for,
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and then the section headings,
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date and time, the
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actions that were taken, and the results.
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Essentially, if we respond
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to the incident on 1st of August 2016,
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we arrived at the scene of 123 main street,
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Anytown, Maryland 12345 zip code.
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Then from there, we obtain a known good local time.
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You can use an Internet
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restore such as time and date.com.
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You can also use your cell phone,
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just as long as you annotate where that time came from.
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Then the next thing that we see in our notes is that we
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secured the same and then
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any individuals that were present,
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we can attach a roster of who was there.
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Hopefully, the third step,
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you've already completed before you
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got to the incident scene.
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But in case you did not,
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you can wipe the media and then
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annotate that in your notes,
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and we'll show you how to wipe media using the in case,
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forensic imager and the hands-on section.
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Then down at the bottom,
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you can see the title of nothing follows,
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followed by an investigator signature,
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and page 1 of 1.
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In conjunction with the notes,
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photography will help build
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credence to your investigation and
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help keep track of what was
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done during your investigation.
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It is often the best way to
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record information of the scene.
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You can sit and write
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a lot and essentially write the novel War and Peace,
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or I can take a photograph of
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it and write some cursory notes of what happened.
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I'm not in favor of writing War and Peace,
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I would just rather take a photograph of
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the scene and record that in my notes section.
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Considerations though when using photography is
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that a flash can cause reflection onto the screen,
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which can distort your image and make it not usable.
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Also, screen refresh rates
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>> can obscure your photography.
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>> So you're going to want to use a slow shutter speed,
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usually about 1/60 of a second,
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and that's about the refresh rate of
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most screens in the United States.
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I think overseas they use a
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1/50 of a second refresh rate.
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However, the slower the shutter speed you can use,
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the better it's going to be.
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However, if you get a lot slower than 1/60
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because the shutter speed is so slow,
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it's going to require a lot of balance and steadiness
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>> in your hands and you're probably not going to be
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>> able to do that without the use of a tripod.
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So 1/60 of a second is generally the recommended speed,
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especially for hand photography.
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That being said, it's very
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important to know your equipment.
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The time to figure out how your camera works
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is before you respond to the incident, not during.
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If you get one of these very expensive DSLR cameras,
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figure out how it works before you get there.
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Then, the old mantra of two is one and one is none.
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Even if you have this very nice expensive DSLR camera,
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if it's the only one you have,
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it's going to break when you need it the most.
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So having something as a backup,
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even an iPhone is better than nothing.
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Never alter the photographs
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because any evidence that you take,
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especially if you're going to go to court,
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it needs to be miscible
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and you have to qualify that evidence.
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Altering the evidence after you take a picture
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essentially makes those photographs
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unusable in a court process.
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Then after you take the photographs,
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you're going to want to hash those photographs.
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Then we go into some detail on
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the hands-on portion of how to use MD5 hash.
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We're going to hash a memory file that we
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>> are going to create from vault memory from the system.
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>> The same process of running MD5 hash on
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a vault memory file is applicable to any type of file.
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So you can hash one file,
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you can hash in five.
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But we'll show you how to do the MD5 hashes.
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