Advanced Networking - #7 TCP/IP & UDP/IP [EN]

Summary

This video in the advanced networking series explores TCP and UDP, two transport layer protocols essential for data communication between systems. TCP ensures reliable, ordered data transfer with error correction, while UDP prioritizes speed without guaranteeing order or reliability, making it ideal for applications like gaming where speed is crucial. The video also touches on socket programming, allowing multiple services to run on a single system, and highlights the importance of selecting the right protocol for different network communication needs.

Takeaways

• 🌐 The video discusses the communication between two computers using ICMP and the need to understand how connections are routed and secured.
• 🔗 The script introduces TCP and UDP as the primary transport layer protocols used for data communication between systems.
• 📦 TCP and UDP provide end-to-end communication, allowing multiple applications on a single system to communicate with their respective endpoints.
• 💻 The concept of socket programming is explained, which involves creating servers and clients to handle communication on specific ports.
• 🔒 TCP is characterized by its reliability, ensuring packets are received in order and without errors, with mechanisms to resend data if necessary.
• 🚀 UDP is highlighted for its speed, without the overhead of TCP's reliability checks, making it suitable for applications where speed is more critical than order or reliability.
• 🛑 TCP includes control mechanisms that can slow down the connection due to its need to wait for acknowledgment of packet receipt before sending the next one.
• 🔄 UDP, on the other hand, does not guarantee packet order or reliability but allows for faster transmission without waiting for acknowledgments.
• 🎮 Examples of TCP applications include MySQL, HTTP, HTTPS, and Minecraft, while UDP is used for DNS, SNMP, and online multiplayer games.
• 📊 The script contrasts TCP and UDP by highlighting TCP's ordered communication and error correction against UDP's lack of order and error acknowledgment.
• 🎥 The video includes an animation from the North VPN blog to visually demonstrate the differences between TCP and UDP packet handling.
• 🔨 The video concludes with a teaser for upcoming content focusing on networking hardware, hinting at the excitement of owning advanced networking equipment.

Q & A

What are the main focus areas of the video script?

The video script focuses on explaining the concepts of TCP and UDP, their differences, and how they are used in networking for communication between systems.

What is the purpose of ICMP discussed in the previous video?

ICMP was discussed in the previous video to diagnose the connection between two computers, which is a part of understanding how systems communicate over a network.

What does TCP stand for and what are its key elements?

TCP stands for Transmission Control Protocol. Its key elements are ensuring that packets are received in the same order they were sent and that each packet is error-free and reliable.

What does UDP stand for and how does it differ from TCP?

UDP stands for User Datagram Protocol. It differs from TCP in that it does not guarantee the order of packet delivery or reliability. It is faster but does not have the same control mechanisms as TCP.

What is the significance of port-based communication in TCP and UDP?

Port-based communication allows multiple services to run on the same system and be accessible over the network. Each service listens on a different port number, enabling the system to route incoming data to the correct application.

Can you provide an example of how a Minecraft server uses TCP?

A Minecraft server uses TCP on port 25565. When a client connects to this port, the data is routed to the Minecraft application, allowing the client to interact with the server.

What is socket programming and how does it relate to TCP and UDP?

Socket programming is a method of building applications that communicate over a network using TCP or UDP. It involves creating a 'socket' that acts as an endpoint for sending and receiving data between applications.

How does TCP ensure reliability in data transmission?

TCP ensures reliability by implementing control mechanisms that check the order and integrity of packets. If a packet is lost or corrupted, TCP will resend it until it is successfully received.

What are some examples of applications that use TCP?

Examples of applications that use TCP include MySQL, HTTP, HTTPS, and Minecraft, which require reliable connections to function correctly.

Why might UDP be preferred over TCP in certain scenarios?

UDP might be preferred when speed is more critical than reliability, such as in real-time applications like online gaming or VoIP, where minor packet loss or out-of-order delivery is acceptable.

What are some differences between TCP and UDP in terms of communication characteristics?

TCP is reliable, ordered, and has error correction and acknowledgment of packet receipt. UDP, on the other hand, is faster, does not guarantee order or reliability, and has only basic error detection without acknowledgment.

Outlines

00:00

🔌 Understanding TCP and UDP Protocols

This paragraph introduces the topic of transport layer protocols, focusing on TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). It explains that these protocols are used for end-to-end communication between systems, allowing for data transfer via port-based endpoints. The paragraph clarifies that TCP ensures reliable, ordered data transmission, while UDP prioritizes speed over reliability. Examples of applications using these protocols, such as web servers, Minecraft, and MySQL for TCP, and DNS, SNMP, and online gaming for UDP, are provided. The concept of socket programming is also mentioned, which allows applications to communicate over these protocols by opening servers on specific ports.

05:02

🚀 Comparing TCP and UDP: Reliability vs. Speed

The second paragraph delves into the differences between TCP and UDP, emphasizing TCP's reliability and ordered delivery of packets, which is ideal for applications requiring data integrity, such as HTTP and HTTPS. In contrast, UDP is highlighted for its speed and lack of ordered delivery, making it suitable for real-time applications like online gaming where speed is crucial. The paragraph also discusses the lack of control mechanisms in UDP, which allows it to utilize the full capacity of the network connection without the overhead of ensuring packet order or reliability. Error detection is present in UDP, but there is no retransmission of lost or corrupted packets, unlike TCP, which has a mechanism for resending data to correct errors. The paragraph concludes with an animation reference to visually differentiate the operation of TCP and UDP.

Keywords

💡ICMP

ICMP stands for Internet Control Message Protocol, which is a network-layer protocol used by network devices to communicate error messages and operational information. In the video, ICMP is mentioned as a way to diagnose the connection between two computers, indicating its role in ensuring network communication integrity.

💡TCP

TCP, or Transmission Control Protocol, is a transport layer protocol that ensures reliable, ordered, and error-checked delivery of a stream of bytes between applications running on hosts communicating via an IP network. The video discusses TCP as a method for establishing a connection between two systems where the data packets are received in the same order they were sent and with confirmation of receipt.

💡UDP

UDP, or User Datagram Protocol, is another transport layer protocol but unlike TCP, it does not guarantee reliable, ordered, or error-checked delivery of packets. The script explains UDP as a faster alternative to TCP, used when speed is more critical than reliability, such as in online gaming or DNS queries.

💡End-to-end communication

End-to-end communication refers to the communication between two endpoints in a network, ensuring that data is transmitted from the source to the destination without the need for intermediate nodes to understand the data. The video uses this term to describe how TCP and UDP facilitate communication between applications on different systems.

💡Port-based communication

Port-based communication is a method where each application on a system listens on a specific port number to receive data. The video script mentions this as a way to allow multiple services, like a web server or a Minecraft server, to run on the same system and be distinguishable by their port numbers.

💡Socket programming

Socket programming is a method of programming where applications create a 'socket' to send and receive data across a network. The video explains that socket programming is built on top of end-to-end communication protocols like TCP and UDP, allowing applications to communicate with each other.

💡Reliable connection

A reliable connection in the context of the video refers to a network connection where data is guaranteed to be delivered in order and without errors. TCP provides this by ensuring that packets are received as they were sent, and if not, they are resent.

💡Control mechanisms

Control mechanisms in the video refer to the processes and protocols used by TCP to ensure reliable data transmission, such as waiting for acknowledgment of packet receipt before sending the next packet. These mechanisms can slow down the connection due to their need to confirm the successful delivery of each packet.

💡Error detection

Error detection in the video is mentioned in the context of UDP, where it has a basic checksum to determine if a packet has been corrupted in transit. Unlike TCP, UDP does not have mechanisms to correct errors or retransmit packets, it simply discards damaged packets.

💡Acknowledgment

In the video, acknowledgment refers to the process where the receiving system sends a message back to the sender to confirm that a packet has been received successfully. This is a key feature of TCP, ensuring reliable communication, whereas UDP does not have such a mechanism.

💡Network hardware

Network hardware in the video is hinted at towards the end, suggesting that future content will cover the physical components used in networking, such as routers, switches, and other devices that facilitate the transmission of data across networks.

Highlights

Introduction to a new video on advanced networking series.

Discussion on diagnosing the connection between two computers via ICMP.

Exploration of how connections are routed and secured.

Introduction to the need for communication data over established connections.

Explanation of TCP and UDP as transport layer protocols.

Clarification on the role of port-based end-to-end communication.

Description of how multiple services can run on one system using different endpoints.

Introduction to socket programming for application communication.

Detailed explanation of how TCP ensures reliable data transmission.

Discussion on the control mechanisms of TCP that can slow down the connection.

Examples of applications that use TCP for reliable connections.

Introduction to UDP and its lack of order and reliability in data transmission.

Advantages of UDP in terms of speed and lack of control mechanisms.

Examples of applications that use UDP for speed and efficiency.

Comparison between TCP and UDP in terms of reliability, speed, and communication order.

Use of an animation to visualize the difference between TCP and UDP.

Announcement of upcoming videos focusing on networking hardware.

Encouragement for viewers to like, subscribe, and engage with the content.

Transcripts

hello and welcome back to a new video on

my advanced networking series in the

last video we have talked about how we

can communicate or at least diagnose the

connection between two

computers via icmp and all the

networking stuff i mean we don't know

the parts that are in between that kind

of like revolver and how the connections

are

routed and how the connections are

secured and how we can prevent false

code for collections that are not

allowed we haven't talked about that but

basically we have

like made a connection between two

systems

now we need to also communicate data

over that connection

and for communicating between

two of these systems most of the time

tcp or udp is used and that's about it

in this video we're going to talk about

tcp and udpip

all right so let's first talk about what

tcp and udp is so both of them are

transport layer protocols so they

operate on the transport layer they also

provide an end-to-end communication as i

already told you we have the connection

and now we need a communication we have

an end-to-end communication which means

that we are port-based so we have an

endpoint on one system that connects

with an end point on another system

and by having this port based we can

have multiple endpoints so one system

could for example provide a web server a

minecraft server a mysql server

everything that you need within one

system and you'll be still able to

communicate with each of them because

each of these systems of these

applications like mysql http hdbs

minecraft dns snmp whatever you want to

have there

all of these protocols are listening to

a

different endpoint

number so for example my uh minecraft is

25565

is the end point for minecraft and in

this case because it's minecraft it is

tcp

and all of these applications basically

built

on top of this end-to-end communication

and this is called socket programming so

basically you can go in and with your c

plus plus application windows you can

basically just tell windows say hey

windows open up a tcp couldn't a tcp

server on port 5 for example and then if

any other computer would communicate

with your windows machine on tcp 5 that

data would be routed to your application

because you have made a server

and if you do a client so you say right

windows i want to connect to the

following server at port5 then basically

windows make sure that this is kind of

like sent to the rights or not the right

system but at least sent out of one

system with the right direction so go to

this system with that tcp port and then

it reaches some other system and then it

basically knows all right you have

requested tcp.5 they i have a server

running a tcp port five so i'm gonna

route this request internally on my

target system to that application so

basically you have two applications one

the client one the server

and with tcp and udp they can

communicate with each other

and making sure that you are actually

talking to the correct endpoint and to

the correct system

let's first talk about tcp which is the

short form for transmission control

protocol

the two key elements of

tcp is that a packet that you send is

received as it was sent this means in

order

and with assertion that each data is

correct so if you want to have a

reliable connection you go for tcp and

you basically

when you send something you are sure

that it is also received by the other

system it's not just send and forget

it's sent and okay done received or

system is not reachable error aborted

but basically if a communication is

possible tcp will guarantee that each

package is received as it was

sent the only issue that we have of tcp

is that it's control mechanisms that

make this

source assumption or this this control

mechanism that guarantees you that the

data is sent as

or received as you send these control

mechanisms will slow down because for

example if you send one packet and the

packet is delayed on its way we always

need to wait until this one single

packet is received until we can send the

next one if we

cannot just say okay maybe i sent

another packet first and then them no we

need to wait until it's there and if the

packet uh fails to be sent or if the

packet is kind of like dropped there was

an issue with the packet somehow on the

way uh the data got corrupted whatever

tcp will resend it and these control

mechanisms slow this connection quite

down

some examples are for tcp are mysql http

https minecraft and many many more

there's also a second player in the

market called udp or user dataframe

protocol and basically udp doesn't care

in what order packets are received and

if they are even received so udp is

basically the complete opposite thing

odp we just spell out packets and say

this is the data i want to send just

send it over i don't care if it's

received when it's received whatever

just do it

the

my thing on udp is that it can leverage

the full speed of the

connection full capacity because uh we

don't need any control mechanisms we

just spill our packages as packages as

fast as we can issue we cannot assert

that they are receiving in order we

cannot assert that they

receive ascent so in case basically

there's still an error detection in the

other piece so if a udp packet gets

damaged it's still kind of like rejected

from the target system but we don't like

we're not we're not gonna resend it

we're not gonna know that it got dropped

we don't have all that control

mechanisms some examples are dns snmp

and various games so by default if you

have a game

a a a online multiplayer game you want

to be as fast as possible to clock your

servers as fast as they can to make a

smooth gameplay we don't want to have 10

fps first person shooters online we want

to have it

desirable at 30 fps

or at least 6 30

60 fps we want to have

a fast server that can do fast decisions

and for that each connection to the

server must be fast we don't care if a

packet gets damaged on the way because

well if the user has a bad internet

connection and us packages are arriving

late or

damaged we don't care we

do not just just do it so if the user

shots but his connection was too bad for

really shooting well he hasn't shot

or

if a user's move event was too slow

because he has a bad internet connection

he might get hit by some other some

other people because he had a bad

connection so we kind of like need this

assertion for games

all right so let's uh take tcp and udp

side by side so first of all tcp very

reliable while udp is not on the other

hand udp is fast while tcp is not

tcp allows ordered communication so

everything that we send will arrive in

the same order uh udp does not do this

it's not ordered uh odp on the other

hand has just error detection so there's

just a a checksum so if there is an

error in the packet i'm not gonna allow

it on the other hand tcp if there is an

error in the packet we ask to resend it

so we can correct the error

tcp has a receive acknowledge so as soon

as the other system

receives a packet it tells oh i got your

packet

while udp does not have such mechanism

we just build packets out

and to visualize this a bit better here

is a nice animation that i have found on

the north vpn block

it is a german article but in case you

understand german you can go to the

article and see full description of

these animations so basically just to

recap here we have a sender and the

sender sends the packet over the

connection and as soon as the receiver

gets it kind of like says check i got it

and then the sender sends the next

packet while on the other hand uh at udp

we just spill our packages over these

connections and we don't care if they

arrive if maybe some packets get dropped

we don't care about this we just spell

out packets

don't care

all right thank you for watching we're

going to see us in the next video where

we're going to go a bit more hardware

sided we have now had many videos of

theory and now we are basically at a

point where we can understand

how basic communication over the network

is

working

and we now can start on learning the

networking hardware this is why we are

all here because we want to have fancy

and expensive hardware that we can show

off to our friends and say look i have

the 7000 dollar networking equipment in

my home to

make sure that you log in over a captive

portal all right so yeah but we're gonna

talk about all of this stuff in the

future

so thank you for watching make sure to

like and subscribe and have a nice day

bye

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