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foreign [Music]

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The topic coming up is
Internet Encryption Part One.

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and we'll go ahead and start
with the first question.

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This question involves blockchain.

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Which of the following statements are true about
blockchain technology? You are asked to choose all

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that apply; please take a moment read to the
choices and then let's see what you're thinking.

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We've got me responses coming into
the chat and let's see what people are thinking.

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C, let's see here; there we go B, B, D and C.


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It doesn't look like anybody's saying A. 
Let's talk about that. Bockchain is centralized.

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If you know anything about blockchain you
know it's not. We’ve got votes for B and C, D and B.

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Blockchain is recorded in a public Ledger and that is the correct answer.

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Third choice: Blockchain only deals with
financial transactions like cryptocurrencies.

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Is that true? Is blockchain only used for crypto?

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No, that is not true. 
No.
That leaves choice D, everyone has the equivalent ability

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to see every blockchain transaction,
which of course is a strong site.

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That is one of the strengths of blockchain. 
Blockchain’s also used for non-cryptocurrency

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Applications. Can anyone name an application
and something that's probably near and dear

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to all of our hearts. Non-crypto-based application of blockchain.

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Go ahead.

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Could you say that again please?

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You said one that's near and dear to
our hearts?
Yes, it’s been in the news a bit.

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How about voting?

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Right.

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Let's see another one could be the food sector.

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You could have blockchain acting like sort of
a trusted third party between brands and consumers.

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It does provide traceability; let's see what we have in the chat.

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NFTs, non-fungible tokens. 

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Traceability is an advantage.

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Does it would allow us for example
to understand and and follow the origin

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of a product and follow it through its path
through processing and even the distribution. 

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As we've mentioned voting, corporate social responsibility. I think pretty much

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anything that is easily verified and not easily distorted. Not just for crypto. 

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The next question: FTPS

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Which of the following scenarios would
an FTPS solution be best suited for?

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Take a moment and look at the responses

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We've got votes for D and B but
then a retraction on the D. 

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Let's say B the second one and
that is the correct answer. A group wants to

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improve confidentiality by using SSL or
TLS to encrypt data file transfers. 

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Choice two works

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in the question because FTPS
uses both SSL or TLS. Choice three

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a group wants to monitor
and manage firewall traffic

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Is that reasonable. No, it's not used to monitor
firewall traffic. 
Choice four: A group wants

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there to be a secure link between the client
and server using SSH to transfer data files.

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Now, at first glance it might
look right but it's not.  

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If I ask what is the difference
between FTPS and SFTP

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What do you think?
That's a good question.
I was going to ask if it was a typo.
No.

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SFTP builds on secure shell protocol and adds
on file transfer capabilities; FTPS builds on file

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transfer protocol and that's a
security and encryption layer.

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Let’s move on to the next question.

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Key entropy: For a cryptographic system
to better withstand brute force attacks,

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it is important that it exhibits high entropy. One element that plays a significant role in

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strengthening an encrypted keys entropy
is by adjusting which of the following?

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I think it's obvious that
you need to know what entropy is.

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So what is it?

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What would you say it does?

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or is involved with?

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We have a response - disorder.    
Let's see we have another response - randomness 

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Unpredictability, uncertainty - we could say that. Insecurity. It’s a measure of the amount of

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uncertainty and attacker faces to
determine the value of a secret

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and is usually stated in bits.  Key
entropy involves the size of a key space.

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Given that, what do you think
is the correct answer to this question?

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Key length. Yes, key length is correct. Let’s 
see what our choices are.
Yep, everybody’s got A.

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Key entropy is improved. Remember we're talking about uncertainty

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Is improved with a larger key space. The larger
the key space basically the better the encryption

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A larger key space has more possible values that would need to be calculated.

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If somebody's trying to crack the key and
of course  you can see where brute

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force attacks would bring into this, the
larger the space the domain if you will

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the tougher it is and the more
uncertainty faced by the attacker. 

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All right good

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The next question: regex

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You use the regex command on a Windows server
to configure security settings to the registry.

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50/50 here. This is true or false.
False. False.
Anybody think it's true

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What are they doing here?
The play on words with registry and regex.
Absolutely, regex

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regular expression - and reg edit - very
very close so kind of fooling around with

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the two words in the meaning saying
yes the answer is false  not to confuse

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regular expressions with registry editing. They just sound alike. I kind of think this

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is one of those really nice questions that the
kind you'd like to see.
False.

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SSH- A secured link is created
between the client and server

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using SSH over which standard TCP port?

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It looks like we have some well-known
port numbers here. 
Oh, no, 22. 
We've got a

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response and people coming in the
chat and it is in fact 22. 

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All right. 443 is what?
HTTPS
Yes, HTTPS

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23?
FTP
Telnet protocol

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All right, lesson learned. Know your well-known port numbers.

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Question

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Types of hardware

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Which type of hardware is needed if you decide to
store digital certificates and cryptographic keys?

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We’ve got some answers coming in the chat.

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Lots of votes for TPM, trusted platform module. Key locker, not correct; Thumb drive, not a

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good choice. That leaves us with Hardware security
modules and TPMs, trusted platform modules.

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How does this relate? How do
the two relate to each other?

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We have a response.

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Again is for software. That's interesting - HSMS are

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hardened tamper-resistant hardware devices that
strengthen encryption practices by generating keys,

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encrypting and decrypting data and creating and
verifying digital signatures a TPM is a computer

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chip like a microcontroller that can securely
store artifacts used to authenticate a platform.

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  The correct answer
here is TPM.

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CISO: The CISO of an organization has
encrypted their company's VM hard drives.

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Which of the following is the CISO protecting?

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We're using encryption; we have responses.

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Great, very good. Everybody - confidentiality

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good? It’s really important to understand the
differences between confidentiality and integrity.

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There are lots of different ways
the question can be asked  I would

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be pretty confident in telling you that 
the most typical is to prevent the present

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excuse me to present a scenario like what
we have here and then ask you which of the

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tenants is being described. I'd say this is
a very common way to ask this question. 

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EAP-TLS: EAP-TLS protocol
requires that both the server side

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and client side are configured with what?

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 Looks like we have me responses coming in

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 let's see what we've got so far.

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 We have a vote for A

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and some more responses, C

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New factor C 

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Anyone else?

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The correct answer here is
a public key certificate.

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Private keys typically
belong to the owner of data.

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Choice three - two-factor authentication.
What do you think about that?
I think

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several people said C

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Extensible Authentication Protocol uses TLS security for

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secure authentication on wireless networks

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This solution typically involves the use of
client certificates to perform Authentication 

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It's not exactly having anything to do with
two-factor authentication or generic token cards

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That particular method permits the
transfer of unencrypted usernames

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and passwords from the client to the server.

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Public key certificate is the
correct answer for this question.

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Next question

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IPSec

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How did the IPSec tunnel mode and
transport mode relates to each other

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 everyone proceed?

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Let's see what else we have here.

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Any other responses?

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And transport encrypts the data  
C is what we're looking for tunnel mode

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Encapsulates the original LP packets and
transport mode encrypts payload data 

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 for the most part knowledge
based type of questions

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excuse me

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 let's go to the next one

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have a look at that we have two identically named

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IPSec. Well we'll try this one too which
of the following is true regarding IPSec
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Take a moment look this over
and I'm going to take me responses

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 We have D, a couple of choices for D

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Is there anything that stands
out it's obviously incorrect?


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More responses too - C D and C. 
All right, obviously incorrect.

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YE stands for internet provider security obviously wrong how about the first one

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Is this close to correct, layer five of The OSI model?

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transport there ye  all right
 that leaves us with ifset cannot

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be implemented unless you configure specific
application supports  really I don't think 

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I think it's designed to encrypt all IP
traffic regardless of the application 

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that really leaves us with Choice D is the correct
answer IPSec is commonly used when running a VPN.

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All right.

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Listening port

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You are tasked with setting up a web
application load balancer to handle all

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incoming client connections and serve web
content to all clients via TLS certificate

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The web app sessions are all TLS
terminated at the load balancer

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and farmed out to the back end web
app web head servers over port 8080.

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What is the main listening port your
load balancer needs to be listing on

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and  we have some responses coming in.

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We have a vote for 443, one for 445 any other responses

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443 is the correct answer. Port 443 uses SSL and TLS

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Port 80. and 81 I'd say would probably be the
most likely obvious and correct answers; 445 is

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used by Microsoft directory services for active
directory and for servers server message block.

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Port 81 used by specialized web servers that are
avoiding Port 80 for reasons like testing websites

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 443 is the correct answer here.

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This question involves salting. How
would adding assault to a stored password

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frustrate an attacker who's
trying to crack your password?

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Let's take a moment and look over the
responses and see what you're thinking.

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We have some responses.

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and the response is …
the second one B 
the second one  and that's that's pretty 

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much everybody's consensus and that is correct
by adding a random value to the plain text

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input of a hashing algorithm  the attacker
cannot use pre-computed tables of hashes 

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The first answer, by slowing them down when you
when you put an initial key that's generated

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from the user password to thousands of rounds
of hasing. Yeah? No.

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Three - The third choice by combining the
password hash with a shared secret to strengthen

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the password Integrity making it impossible to
Decrypt…
Hmmmm, no, and by including signs and warnings

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of legal penalties against password cracking and
I don't think that's going to be a really big

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deterrent that one's obviously wrong
as well. All right very good everybody in this

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case it's just it's one of the ones like the other
ones where it just it's a knowledge-based question.

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So pretty much you have to understand what
salting is and how hashing works and then 

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adding the salt value definitely
takes it to a new level of difficulty.

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 I also would note that I tend to shy away from
things or saying things like impossible to decrypt

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 mostly it's a game of resources, computing power, and time.

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The one that stuck out and this one for me was
none of the other ones used the word value and

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I know that it had something to do with adding
values and random values

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you really do have to look at the language
in the both the question but also in the responses.

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To see if you can see something that
doesn't belong or which of these things is

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not like the others, all of these 
little tests that you can use to help you.

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I think it's equally important
to be able to do that because

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I think anybody can get rattled in an exam. I think back to

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some personal experiences I've had, I remember
when this was years ago but it was probably

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I guess the third time that I had to test to
re-up my CCNA and at this particular incident

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 I had gone to a Pearn VUE testing center and
it's funny and and I don’t really have a good

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reason for it but I just never expected that 
someone would be in there and perhaps not testing

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uh for an IT certification and I don't know maybe
I was just  focused on  recertifying my

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CCNA and  I was probably halfway through the
certification exam and  another person

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had come into the room and they were sitting not
close to me but within a very short amount of time.

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I couldn't help but hear them typing madly I would
describe it on the keyboard I'm also quite loudly

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like I guess they were striking the keys on the
keyboard pretty aggressively.

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and it was nearly non-stop and  I
I would catch myself  listening to

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it or maybe even getting a little annoyed
by it and I think once I even looked over

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and  from what I could tell just by a quick
glance this person was typing an essay and

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 I like I said it just didn't dawn on me
that you might have somebody coming in there to

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test out and maybe their test was to 
type up several pages of narrative and I really

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had to fight to get my focus back for for a
couple of minutes and I guess I was a little

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surprised at how much it kind of set me off
of my game and that it actually took me two

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to three minutes maybe two minutes probably no
more than that but that's still two minutes to

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 refocus on on what I was looking at and
it was more of a performance type of question

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and the lesson there obviously
is to  try not to be distracted and

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to try to to stay focused  when
you are negotiating questions that

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 perhaps don't require a lot of time to answer
maybe it's something like the true false question

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we saw I think in the last session  or maybe
a straight-up knowledge-based question if you

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can answer it and say 20 seconds maybe even less
if it's just like like I said like a true false

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that gives you perhaps another 45 seconds to put
back in the time bank  that when you do approach

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a question that maybe is performance related and
could take you a minute or maybe a little more

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you have that extra time and  I've learned and
trained myself to think about it in these terms.

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Just because  for me no matter how much
money I have into it it's still running out of my

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pocket and I have a little bit of a sense of pride
I've never failed a certification exam. I've always

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passed on the first attempt but I generally tend
to over prepare for them if there is such a thing

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 but that that particular experience really
 kind of threw me for a minute and 

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really made me  come to the understanding that
people are there for lots of different reasons

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and not just  reading questions like
we're doing and then choosing correct one

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or more correct answers from the list.
Now let's go to the next one.

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Types of Hardware II

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Which type of hardware is
needed if you must perform

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centralized public key infrastructure
management for a network of devices?

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What do you think?

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We've got responses coming in.

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It looks like everybody’s selecting A and that is the correct answer.

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Hardware security modules - something obviously
incorrect when the answer choice is shown.

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Blockchain? 
Blockchain. Yeah. Sniper is an automated scanner that can be

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used during the penetration test to
generate and scan for vulnerabilities.

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the password vaults or password manager or
password locker is a program that stores

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usernames and passwords for multiple applications
securely and in an encrypted format.
Yes, HSM.

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Next question

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Digital signature and decryption: Creating a digital signature and decrypting a message

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both utilize which of the following (and you're
instructed to choose the best single answer). 

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We have some responses coming in

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 We have votes for C

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Anything else?

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What would you say is obviously
or the most obvious incorrect answers here?

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Private keys.
Which? symmetric?

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Go ahead
I was thinking both 
So, with symmetric keys you have two disadvantages

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In using symmetric encryption and that is
how do you communicate the key to the party who

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needs it to decrypt the message. You must ensure
that whatever you whatever way you communicate

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it the key is sent in a secure manner and
that makes it tough. Both for C 

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Asymmetric encryption is used in key exchange
email security web security and other encryption

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systems that require key exchange over the public
Network. Two keys - public and private 

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cannot be derived to the public;  the public key
can be freely distributed without confidentially

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being compromised.
Anybody changing their answer ?
How about asymmetric private keys?

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All right, let’s see what we have here.

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C

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Why do you think C?

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Uh I I didn't quite get
the public and private part

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The public and private part, yeah, a asymmetric
private key not a public key because

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right the private keys held by the owner
of the data messages are encrypted

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with the recipient's public key the messages
encrypted by the recipient with their private key

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The correct answer is asymmetric
private keys.

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Next question

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Digital signature - What is a digital signature?

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What are you thinking?

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 Responses coming in.

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We have lots of people saying A,  a plain text string that is hashed

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using a private key

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Anything obviously

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 incorrect?

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Anything stating public key 
All right. 

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That leaves us then with a plain text
string that is hashed using a private key

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or a hash that is in that is then
encrypted using a private key

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Yeah it's B. 
It is the correct answer: B.
A hash that is then encrypted using a private key.

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okay okay oh we have some more Deans okay not a
few responses for B right B is the correct answer
 
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okay