all right I got a couple questions for

you guys uh when we last met we're

talking about the OSI model can anybody

tell me

what organization is responsible for

developing this model

is that you are you guys want to start

easier questions Monday morning what's

that ISO yes yes ISL

now what's nice about that is the

letters are still in the OSI right

they're just flipped over so it's nice

way to remember that and why would the

international standards organization

develop this model I mean they create

other models they cut other standards

for us to follow why would they develop

the OSI model

yeah the idea is that we can foster

competition but yet still keep

compatibility

so we have the difference between

proprietary protocols and open protocols

correct

and so you can still have proprietary

protocols but what that means is that

the corporation owns them and they're

only ones allowed to change them and if

you want to use them you have to license

them

but open protocols is

we're going to create the standard

you're allowed to look at them

you can modify them but you have to

create a variation of it like the

802.11n or the 80211 B

they're still using the core standard

right

but then somebody has enhanced it so

they went to end

so Fosters competition but more

importantly allows me to know when I go

shopping

what to look for to make sure they're

compliant like when I buy a USB hard

drive I should expect on my home

computer that there is a port

that accepts that USB hard drive

back in the day it was always a

nightmare because we had different ports

on the back of our computer and it was

like okay this one plugged and this one

this goes to that one and somebody said

this is just stupid why don't we have

one universal Port that accepts

everything

and once again where that's starting to

grow again we got Thunderbolt we have

firewire we have USB so it's like why

can't we just have one that rules them

all

so standards allow me to know that when

I go shopping the devices I buy are

going to be compliant

right I threw out the 802.11

that's an example of another standard

but it's a wireless standard yes but

what organizations responsible for that

they're also responsible for this one

now it's always interchangeable because

you guys know this 802.11 as

Wi-Fi right

and you know this one as

probably faster than that's what I

should put in there what's that

IEEE

for some reason

Cisco in this curriculum is all gung-ho

about you guys knowing these

organizations

I don't understand why other than when

you become a network engineer

now you're getting down to nitty-gritty

you might be developing new interface

cards

that you'll have to look at what we call

rfcs

anybody tell me what RFC is short for

yes request for comments and it's not

read the you know you guys rfc's request

for comments and what how does that

system work

remember we're talking about open

platform right

so you guys can go to the IEEE site

read over the 802

3 or the 802.11

and start publishing your own

variation

or maybe fix a bug

and add your post from the rfcs and so

you're looking at the rfcs as ways to

see what's going on in Industry so I

guess that's the only kind of BS excuse

I can give you why Cisco is jamming down

into organizations down your throat

what's the other one that sort of

Fosters the open platform for the

internet

it's more of a society thing give you a

hint

eye soccer eye social the internet

Society

and their old big deal is to try to keep

things open and keep the internet

growing and people sharing

and

so we have the OSI model that's

developed by the iso and what is the

whole purpose of this well we said it's

too Foster competition but it also helps

delegate responsibilities

and it also can be used to understand

the communication process and that's

where we were at last week right

dissecting the communication process

from the sender to the receiver what's

the first layer the upper layer of the

OSI model

application this is also known as layer

what

what happens here what's the

responsibilities if you were to a

designate you have a big Corporation

you're designating some people jobs

and you say Okay I want X number of

people to do layer seven what kind of

skills are you looking for a later seven

job description you have

okay so you're looking at programming

skills these are people that develop

applications design web pages and

nowadays we're just calling them web

apps right but in any case we're just

trying to say that these are our

software engineers

these are people that write code

and what does applications do for us

they give our computers purpose

you go with that so the application

layer acts as an interface

to the network

if you are writing code or developing

software that uses a network connection

like for instance if you are developing

a web browser it's always good to have

these examples if you're designing a web

browser not a web page but a web browser

what protocol do you need to agree to so

that your application understands

this process

what's that

http

so HTTP is an example of an application

layer protocol

and a list of others like DNS FTP pop

SMTP and we'll get into those as the

semester progresses like I said lab for

this week you guys are going to be

getting into HTTP and

DNS

now when I say their application layer

protocols

I'm saying their responsibility is to

work with the user to prepare the data

to be ready for the network

and so the OSI models interconnected

layers

it's going to encapsulate things as it

goes down

so here I am at the application layer

I'm using a web browser and that's stuff

that I'm asking for or I'm sending via

my web browser it's passed down to the

layer six what is the name of this layer

what are the three responsibilities for

this layer what's it going to do with

that HTTP stuff

it's going to encode it we might use

ASCII

to accomplish that

encrypted which it might use what

SSL or TCL the list goes on and on in

fact this is a huge dwelling field

if you guys are looking to make a lot of

money with a very little bit of

Education you want to go on the security

try to give number security courses you

possibly can get and if you're really

good at it you're really fascinating

about and have great math skills in

cryptography or cryptography is the area

to go

trying to create code that can't be

cracked and right now the NSA is

bragging that they can crack every

encryption method out there in a couple

seconds

now what does that mean they're going to

hire more photographers the correct

credit card that they can't crack

because they can't crack it to make it

feel it's safe it's safe communication

all right the big growing area what's

the third

compression yeah they want to make this

stuff

smaller so it takes

less bandwidth to deliver it if you will

all right and so an example of

compression I believe I gave you guys

was like gzip but this stuff goes on and

on and on

what's the next layer and don't get cute

and say layer five

now eventually I will get lazy and I'll

say that stuff happens at the layer

three and then you need to say oh that's

the all right so here I am layer five

and uh we called it the session layer

if I had to uh roll that all up in one

word it's just going to be management

dialogue management to keep your

connections alive that's it

all right so I'm saying keeping

connections alive

see the application layer you're the

user

they could be using multiple

applications all at once

that require the internet

you can have an email program going on

you can have your torrent stuff going on

you can have your web browser going on

and it would gets really interesting is

with even those applications there could

be other connections like for instance

if you're browsing the web and you're

watching a video

and you could also be using email

which we call webmail

and you could also be using DNS

ironically

so just within one connection we can

have multiple other connections

I mean we talk about HTTP we're only

talking about HTML and a generic web

page but that has evolved we're on web2o

so we have plugins which are going to be

at the presentation layer that's

designed to sort of work with the

browser and the content provider does

that make sense

and the way we do that is by

establishing separate connections to

each of those services

and as for this layer comes in

anybody tell me what the layer for

transport layer

do not think transport as being this

the bottle

and you move it over here to its final

destination that's not what we're

referring to at the transport layer

it's your job it's responsibility

you get the segment

to the right application or service now

when I say application you guys need to

think client when I say service you need

to think server

is the symbiotic relationship between

client and service clients make the

request service try to fulfill their

requests so clients use applications

servers use services

are applications

they just are designed to run in the

background if you're a Linux person what

do you call services

demons

got its name because they're running in

the background taking over the server

right

fulfilling a role so if you are running

a Linux web server you might have Tomcat

or Apache web service running in the

background

and it's listening

it's listening to a particular port

now I said Apache I said web server

right web services what port is This

Server going to be listening to what

number or what address is it going to be

listening to

or an 80.

480 is the default port for web delivery

so on my server

obviously if it's going to be accessed

from the public it's going to have a

connection to it but inside This Server

I could have different Services running

so this server needs some kind of

mechanism

to identify

what the communication is

so when a message comes in here

this server's transport layer

you're going to be looking for

the destination port address

and if that port address is 80 and this

service is configured to listen to Port

80 the transport layer will now deliver

or

transport the message to the right

service okay see where the name came

from

not about picking it up from one source

and sending it to the receiver that's

another layer

what it's about is when the message gets

to the server

what service on the server needs it

so think about it as software delivery

okay

how does it accomplish that

how does the server know to look for

Port 80.

is that the header

see at this point in time

we have generated data

and the transport layer is going to take

that data and break it up when we break

it up what do we call it

and that's what the pdu is

for the transport layer

that happens guys let me know if I

misspell something

so the transport layer is going to take

the data it's going to segment we call

the segmentation

why why take something

that makes sense

and rip it all into a bunch of pieces I

mean if I deliver this all crumbled up I

can do this

and I say to you guys

here it is see if this makes sense to

you

doesn't it take all this extra time it

doesn't seem like it's wasteful that I'm

just taking that message and ripping it

up into tiny pieces just so somebody can

have fun gluing it back together

why would you do a thing like that

you notice I broke it up and destroyed

it to different people in this classroom

but that's only one page I got a whole

bunch more I really have some fun

it seems like the segment later could do

something else with its time instead of

just ripping my data apart

that's one

we don't depend on one and only one way

out of the classroom

so if one piece gets lost we have the

other stuff to work with

now that can work

sometimes

but that might not work other times like

what if that piece that I lose

is the end of my file

am I going to open up my file

I'm going to get like an EOS problem and

defile

problem

ah but that would be wasteful we only

have bandwidth that's only so much so it

wouldn't make sense to be sending

multiple copies of them all over the

place

gotta have some kind of system of

checking

to see if things got there we call this

reliable delivery

in order to ensure that we have reliable

delivery

we need to also make sure that once

but I'm taking these pieces and throwing

them all over the place

it's quite possible that maybe the end

is going to get there before the

beginning

so what do I need to do about that

this layer if it's going to rip it apart

better glue it back together but also

better glue it back together in order

so it makes sense for the application

layer to be able to display it to me

otherwise it's like taking a jigsaw

puzzle and just jamming the pieces

together and say I put it together well

it looks like crap the objective is to

put it together so it still looks like

the picture that you're working with

you good

so we get sort of

efficiency in the fact that the messages

are dispersed over multiple connections

multiple pathways

why do I say sort of efficiency well we

lose some by breaking it up right

because we've got to add all this other

stuff to keep track of it but we gain it

because we're saying if I had multiple

ways out of this classroom and everybody

wants to get out here in a hurry

after you go there if you go there if

you go there correct

that's like the difference between 17

and what 352.

one's a four-lane highway the other

one's a two

the other thing is sort of security

how many people take the same way to

work or same way to class all the time

from home

if you guys have a stalker it has made

my life a lot easier foreign

so if we're not encrypting the data it's

like a big Corporation covering their

assets

let's ask NASA they're known for this

the person making the handle for the

door doesn't know what door belongs to

and what project is part of

they're making one little part

a piece to larger puzzle

so it sort of builds Security in there

because you don't know what the left

hand is doing

so you guys can't collaborate

and try to you know sell the ideas to

another company

likewise if we send our segments all

over the place it makes it harder for

one person to get the whole entire

message

but is that the intent for the server to

get the message

so now we need to identify who gets the

whole entire message

that's another layer that's another

responsibility

right now I'm talking about managing the

data so that it can get there

in its entirety

transport layer

there's all Communications need to be

reliable

thank you

that's saying reliable though

so it is all Communications process need

to be reliable

I really

like my job

could you fill in that blank

you could try

what if I said I'm on a phone with you

guys

and we're talking about meeting I don't

know about dinner or for a movie

and we say okay well I'll be available

at 6 30.

and all you hear is at 6 30.

we already made plans that we're gonna

go to the movies but we didn't know what

time

right because you heard well let's plan

on going to movies but what time would

you like to go to the movies

and then all of a sudden I'm answering

back to you I say I will be available at

6 30 but all you hear is at 6 30.

could you say oh I guess he's available

at 6 30.

what if they didn't come in there and

all you heard was I'll be available at

would that work

but it's the same communication right

we're talking about going to the movies

I can't switch between reliable delivery

and unreliable delivery

it's either going to be one or the other

either you want me to make sure

everything got there

or you don't

you want me to stay out of this

conversation so that the conversation is

lean and mean more efficient

so as a programmer I'm going to decide

what protocols

my communication my application are

going to use

if I'm developing a web browser I'm

going to require that I use the TCP

protocol of the transport layer

TCP is short for transmission control

protocol

in short same order delivery

reliable Communications

no no problem

so we said same order delivery reliable

communication and develops a mechanism

to detect when things fail and to regain

those we call this flow control remember

we're talking about flow control where

our server can get inundated with too

much information or a client can get

inundated so it starts dropping things

so TCP has a mechanism to control how

much segments it's going to be sending

out

so it doesn't overwhelm

the receiving person

but in order for TCP to do that what's

going to happen is it's going to take

part of that data

and it's going to slap a header on there

and that header is going to be pretty

massive sometimes it might even bigger

than the data that you send

and in that header they're going to have

what they call sequence numbers we call

these fields it's going to have

acknowledgment numbers

see the sequence numbers are like little

tags that we know okay you got part one

you got part two you got part three the

acknowledgment numbers are away for the

server to tell them which one it has

received or what it expects to receive

next

acknowledging what it's already came in

what else

well we need to be able to put these

things back together some sequence

numbers help but we also need to

identify

what service or what application

is using it

so there's going to be Port addresses in

this header and that's the only kind of

fields that we need to know at this

particular moment is going to be a

source port

and a destination port address

The Source Port is randomly assigned by

the client's operating system by

definition the client is the one sending

the data in this communication okay

so the sender's operating system

is going to randomly assign a port

address why would the operating system

be responsible for randomly assigning

Port addresses for the source and only

the source

well we talk about using a web browser

right in this example

is Internet Explorer the only web

browser out there thank God

so there are certain applications or

websites that require you to use that

awful web browser correct

so it could be possible you guys could

have multiple web browsers

on your computer running at the same

time

that understand Port 80 or http

but

when I click in Internet Explorer I

don't want that page to reappear in

Firefox

otherwise every time I click on things

I'm going to be wondering where the hell

to go in my computer

so the operating system will stamp some

identifier

to the application

that started the communication process

so web browser doesn't have to have Port

80 as the source address none of them

will

it's going to be any number over 1024.

it's going to be randomly assigned up to

65 535 yes you will have to know these

addresses not all 65 000 of them but the

ranges we'll get into that we get the

transport layer all this is the grand

overview

so when I have multiple web browsers

I'll be randomly assigning The Source

port

what about the destination Port I cannot

randomly assign that if I'm using HTTP

I'll be putting in Port 80 here for

Destination so this way my server

nose

what to look for and what to grab from

their resources you've been there

all right

what if our communication process

doesn't want all this extra overhang

adding all these fields keeping track of

things controlling the flow what if I

throw it out there like I'm doing today

I didn't say David did you just get that

did you understand what I said

Tony did you get that do you understand

what I said

Dominic did you get that no you didn't

get it okay so let me say this again so

the destination Port is going to be port

80. do you see how long it would take me

to accomplish a lecture in this class if

I tried to verify every single one

of you making sure you understand that

would your education be improved yeah

because I'm not letting you guys go

I'm making sure that you get it and I

will drill it until you say acknowledged

and sometimes that might take me months

to do

and we only scraped the first chapter

you guys going to be experts in the

first chapter

do I do that in this class

no

I use unreliable delivery

unreliable

that's got to be awful

seems to be working for the last couple

of centuries

most of the time that we're lecturing

we're using unreliable delivery

most of the time people is like hearing

themselves talk they don't care whether

you guys get to each other or not

so an unreliable delivery

the transport layer uses another

protocol

called UDP

use your datagram protocol and in that

protocol we want to be really simple we

want to send as much of data as possible

we're still going to segment it okay

guys we're still going to segment it

but the size of my segments might be a

little bit bigger

than the TCP

we good there that allows me to send

more data

at a single time which would make the

process more effective

so I'm not wasting it by resending it

I'm not wasting it by creating all the

overhead

I'm just saying I'm going to send it to

you guys and if you don't get it what

are you supposed to do

raise your hand right

let me know

that's instructions I'm telling you guys

that's the application so if I choose to

use UDP

and I choose to say that this

conversation is either important or not

important if it is and I want as quick

as possible delivery method and I'm

going to build up in here way to

checking

the data myself

and that's what uTorrent does

I mean after all in order for you to

successfully download a file off a

uTorrent you need all the bits from

beginning to the end

but it would take uTorrent a very long

time every time they send five bits did

you guys get those last five bits yeah

send the next five all right send in the

next five

you guys get those next five yep and the

next five all right send the next five

the year before it's like you know what

send it send it out of order so when you

guys are watching your little progress

bar you might see certain areas filling

in it doesn't go from beginning to end

unlike when you download a file using a

web browser

you know like on blackboard you click on

a link like package here so you download

it doesn't it start at the beginning you

work its way to the end of progression

because HTTP uses TCP

and it takes it a lot longer

but ensures that every piece got there

nudity

so examples of UDP delivery is videos

and audio why are those two the prime

examples they don't have to do but they

are

the massiveness and you need it as close

to real time as possible

otherwise if I was having a conversation

or if I was watching with a video using

TCP every frame I get is going to want

to verify it

so I'm watching One frame and there's a

lag and another frame and then there's a

lag and then another frame

or I'm having a conversation with you

and it says I

my

name

is

and that's going to take a long time to

get there

so anything that's really time sensitive

the other thing is let's think about

videos and conversations vocal

conversations

you know ideally a video is about 30

frames per second that means every frame

is only about one-third of a second

and here I can detect that anything

beyond that your eye can

but

a whole length movie could have billions

of Franks

are you going to be too upset that you

lost one frame at the billion

no what if happens if you start losing

more of those things

yeah you just drag that you grab that

little status bar and drag it back and

let it rebuffer

and that's why we buffer

you ever also notice that certain parts

of the movie will load up faster when

you're streaming it over the internet in

other parts because remember we break it

out in segments the end could happen

before the beginning

but the application layer knows not to

play that just yet so it queues it up in

its buffer

until that time code is reached

so it's not like oh gee now everybody's

off the internet and it's going by fast

that could be possible but it could also

be it took that one message a long time

to get there and all the other messages

sound a shortcut

all right

so you're not you're only forced from

doing that by what the programmer so I

chose to use as a developer you have to

decide what you're going to give up with

reliability over performance

but if you're in a really questionable

area

you might choose liability just to make

sure that everything gets there

so we start the encapsulation process

excuse me by adding a header a UDP

header is going to be a lot smaller than

a TCP header hence

more efficient better performance

earlier I proposed oh before I get there

I got to tell you something else

remember I told you that we're going to

have multiple applications probably

running concurrently

and we're probably going to have

multiple computers on our network using

this uh using our connection

probably concurrently as well

so not only do we gain segmentation as a

way of disbursing our messages across

several connections

but we also allow multiple people to use

the same connection rather

simultaneously now I put the word rather

simultaneously it's just like time

sharing when it comes to your processor

it happens so fast it looks like your

computer is multitasking

which doesn't really do it at least the

old process is never really multicast it

did one task and the other task rather

extremely fast it looked like it did it

at the same time all right guys

so likewise when it comes to networks

most of our connections can't handle

parallel connections that is concurrent

connections at the same time so what we

do is we Multiplex the conversation that

is we take segments from different

conversations and interweave them

together so it looks like everybody's

using the same network connection at the

same time

clear about that so by segmentating the

data it also allows for multiple people

to use the same connection

so there's no monopolization happening

all right so earlier I posed a problem I

said that the transport layer is

designed to identify the application the

services that are receiving it but

because these packets sorry these

segments are going to be traveling all

over the internet

different Pathways we need some kind of

mechanism

that when that message gets to it it

knows what Pathway to send it down to

so all three gets to the Final

Destination

that's what this layer is all about this

is called the network layer it gets its

name because

when those messages or the segments are

being distributed across the network

this layer has got to be used by a

particular device

to Route it along its way

and that device is called a

router

so not only do we have protocols

to identify each layer we also have

devices

so when you get to about layer three

you're going to get into specialized

devices layer four and up probably going

to be internal on your computer into

your operating system into your end

device

in fact when you get into Windows you'll

see the transport layer there's a

protocol installed called TCP slash IP

and you can go in there and make some

settings like the flow control

like segment size

so here we are layer three it's going to

take that segment and once again

re-encapsulate it so now we have the

segment

we're going to add a header to it

that's for each segment by the way

we re-encapsulate it we're going to call

this

a packet

what's the difference between a packet

and a segment

a packet has information

used to identify end devices

the key is identifying end devices so

the sender

and the receiver

I before you accept after C is that the

rule

I hate the English protocol

that's just crazy I always misspell

receiver

so that is to say

in this header

there's got to be an addressing

mechanism

what addressing mechanism have we

learned so far

or at least explored I should say

exactly hence

the protocol used in layer three

is typically ipv4

but it's not the only and I gotta beat

this out of you guys because it took me

a lot of years myself to convince myself

all the protocols do exist

IP is one

we have apple talk is another we have

net value is another we have ipx is

another we have something called

connectionless Network Services

so they go on and on IP is the most

popular why why is the IP protocol the

most popular compared to uh let's just

throw apple on the bus so Apple talk why

is IP more profit than Apple talk

open

as an open protocol

and so more people more willing to adopt

that because it'll cost them any money

so when HP decided to make a network

connected printer

and decided to say oh I'm not going to

go buy Apple talk and at one time

especially in the 80s you would have to

buy several different interfaces for

your printer to get them to connect or

your end device

and so now it's like you look back out

of there the only thing you're going to

see is either a USB port or an ethernet

port that's it

nowadays you can buy these computer

documents I'm sorry these printers

without connecting wires to it as long

they agree to the 802.11. so this is the

nice thing about openness

if more people start to use it it starts

to become a standard

and if popularity dictates that's the

only thing we're going to learn

in this course but I will put that

little slime print it's not the only one

okay if I'm making this point expect to

see it on one of your exams one of my

exams that I make for you

question

they won't ever do it again they it cost

them too much financially they realize

they weren't as powerful as they thought

they were so they had to start

developing things that were more

accommodating yes because when you start

seeing the popularity of the internet

and by the way that's the only reason

why we got rid of all this well not all

of it but most of proprietary bullshit's

been gone because of the eye socket or

the isos the internet Society

hosting and making things open and free

for the market has caused other

companies Say Hey I want to use my

product well I'm only going to use a

product if I can get on Facebook

in fact isn't that the biggest complaint

about going from Android to iPhones

or the iOS

what's the biggest thing that Android

has going for itself right now

it still plays Flash

whereas the iOS says Apple's like

sticking it to uh Adobe saying nope

got security problems and you're too

battery hungry so we're not going to

allow any flash content through our

devices and it's annoying it's really

annoying and you're trying to go onto a

website in this open free platform and

it says oh you're using iPad sorry tough

luck

so people buy Android tablets

so this is that philosophy come into

effect so the network layer is going to

basically set a source IP address and a

destination IP address

The Source where it came from

destination where it's going the

important thing is in that address is

going to be a network address and that's

how routers know where to pass things

along

all right after we get done with the

network layer we go to Layer Two

this is my favorite layer out of all of

them folks

data link layer

okay when I say the word link what are

you guys thinking

give me a basic Bare Bones generic

definition of a link

yeah it's going to connect two things

together right

all right

everything up to this point looks like

this

if you see that what's the generic term

for that

what would you guys call it and don't

call it binary

but it's what the machine uses to store

what

data

because what's the definition of a

computer

anything that receives

data processes it and converts it into

information right

so that means the machine sees it like

this this is data so this layer is

called the data link layer

it's taking that and linking it to what

the last layer layer one

which is known as the physical layer

this is Layer Two is the last layer that

the encapsulation process

occurs

in fact we get done day in the layer two

data link layer we produce a frame

what is a frame it is a packet

with a header

and a trailer

this is the only layer that we add a

trailer to the encapsulation process all

the other layers said a header is just

fine

why does this one have

a trailer

this is the last time in fact this layer

has two sub layers one's called The

Logical layer then the other one's

called oh we're blinking so I'll lose

this I hate that hopefully it's still

recording but whatever you guys are

watching this video it probably got cut

right here at this point which is almost

just in time but regardless

what this layer has two sub layers one's

called The Logical layer the other one's

called the Mac layer the media Access

Control layer and it's linking the

physical world with the logical world

how does it do that

with things called Mac addresses

see earlier we talked about IP addresses

as identifying the sender

and the receiver the source and

destination before that we talked about

Port addresses right and what were they

used to used for

to identify the application and the

service correct so these addresses are

used for identification

transport applications and Services

Network

Thunder receiver because that's there's

addresses here we call them physical

addresses what do you guys think they're

going to be used for

along this journey to get from here

to there

might be several different Pathways

several physical connections like for me

to get from here to my office I gotta go

out of that do a walk across this carpet

run go up these concrete steps or across

a tile floor back on the carpet rug and

in my office

now since it's Corning I really don't

care but if it's at home

you might want to take off my shoes

right

if I'm walking on tile at my house I

really don't care to take off my shoes

grab the mop clean it up gun

if I got muddy shoes and I walk on my

rug

somebody's gonna kick my ass

right you see these different physical

properties and how it affects Behavior

so somebody told me you see rug take off

your shoes you see tile walk on it

likewise this layer right here

there's rules protocol that we tend to

use in a wired based Network like the

one that you guys have right in front of

you is the ethernet protocol or the

ethernet standard

and in that protocol they are going to

tell me

when a frame begins and when a frame

ends and that's why it's important

that this layer produces a trailer

can you guys tell me this wire is

actually unplugged now

are there any zeros and ones on this

wire

why do you say that

does not plug in anything

well let me tell you this water is made

of Papa

what have we learned about copper

it conducts electricity it's also

susceptible to what we call EMS you guys

don't believe there's any zeros and ones

on there when you get home tonight and

you're bored go grab a metal pipe

yeah six feet ten feet will do

and take this wire strip the insulation

off because you need to get a charge out

of this exercise

and wrap it around that metal pipe

and then go find the 600 volt power

lines those big transmission power lines

and drop it underneath it

and hold it for a second

the longer the pipe The More Voltage

the more charge you'll get out of it

they call this induction you're starting

to see this with wireless chargers

we get in charge of batteries without

any wires

so once again are there zeros and ones

on this wire

absolutely

the tree falls in the forest and

nobody's around to hear it it does make

a sound does make noise

so

where is it coming from our atmosphere

David question

protect it yeah yeah exactly you're

using the same induction all right so

there are zeros and ones on this wire

all the time

how do I know those zeros and ones are

my data or they're just bogus signals

how do I know that this is just some

random mess

verse

I'm sending Morris code

this very rarely happens

in nature where it's very systematic it

has a beat it has a tone there's timing

involved and you guys could time in if

you want because you know

the intervals right

when I start seeing that I'm like wait a

minute that's pretty weird

that

I'm getting clap nothing clap nothing

clap

I might get

some random crap

but this seems like it's done

intentionally

so your interface card perks up

it says I know that pattern

this pattern

is telling me the beginning of a frame

now this pattern goes on for so many

seconds I don't necessarily know

when it began but I do know this

that should end the pattern

right

so anything after that is going to be my

data

now we need a trailer

and that might be something like this

and that ends the transmission

that's how I know to grab a frame

where the frame begins and where it ends

because once I know the beginning of my

frame I can remove the header

and what do I get when I remove the

header in the trailer

I get the packet I pass it up

now that I got the packet I remove the

header and what do I get

and I pass it up now I remove that

header and a way to build the data back

up to its entirety and I pass it back up

to the application there

and that's the communication process so

I ran over I will see you guys some of

you tomorrow other of you definitely on

Wednesday you guys take care watch those

videos

and uh

stay tuned

yeah