Networking For Hackers! (Common Network Protocols)

Summary

本视频深入探讨了网络协议的基础知识，强调了理解网络协议对于使用工具如Wireshark和进行黑客活动的重要性。视频首先介绍了IP地址的概念，解释了公有和私有IP地址的区别以及NAT的作用。随后，介绍了DHCP协议如何动态分配IP地址，以及IP、TCP、UDP、ARP、DNS、FTP、SMB、SMTP、SNMP、TELNET和HTTP等协议的功能和重要性。通过这些协议的概述，视频旨在帮助观众理解网络通信的基本原理，并为进一步学习网络工具打下坚实的基础。

Takeaways

• 🌐 IP地址是数字世界的基础，允许设备进行通信和连接。
• 🔄 私有IP地址在局域网内重复使用，通过NAT设备转换为公有IP地址以访问互联网。
• 📦 DHCP协议动态分配IP地址，有助于管理和优化网络中的IP地址使用。
• 🚀 IP协议作为数据包在互联网上的旅行指南，定义了数据传输的目的地和来源。
• 🔑 TCP协议通过三次握手建立可靠的连接，确保数据包的正确顺序和交付。
• 🏎 UDP协议不建立正式连接，适用于对速度要求高而对数据包丢失不敏感的应用。
• 🔍 ARP协议将IP地址映射到物理MAC地址，对网络设备正确路由流量至关重要。
• 🌐 DNS协议将人类易于记忆的域名转换为计算机使用的IP地址，简化了互联网导航。
• 📁 FTP协议用于网络间文件的传输，遵循客户端-服务器架构。
• 🖇️ SMB协议允许在局域网内共享文件、打印机和其他资源。
• ✉️ SMTP协议是电子邮件传输的基础，负责将邮件从一个用户发送到另一个用户。
• 🔄 SNMP协议用于管理和监控网络设备，但若被攻击者利用，可能导致严重后果。
• 🔗 Telnet协议允许远程会话，但由于安全性不足，已被SSH等更安全的协议取代。
• 🌐 HTTP协议是互联网上的主要通信协议，用于网页、数据和多媒体内容的传输。

Q & A

IP地址在数字世界中扮演着怎样的角色？

IP地址是数字世界的基础，它们允许设备进行通信和连接，是进行电子邮件、视频聊天、观看YouTube视频、发送推文和浏览网页等功能的关键。没有IP地址，设备就无法在网络上被找到和通信。

为什么需要区分公共IP地址和私有IP地址？

由于IPv4系统只有43亿个IP地址，不足以覆盖所有需要连接到互联网的设备，因此开发了私有IP地址系统以在局域网（LAN）内重用一组IP地址，这些地址在互联网上不可直接访问。

网络地址转换（NAT）设备是如何帮助局域网内的设备访问互联网的？

NAT设备将局域网内的私有IP地址转换为公共IP地址，使得使用共享的公共IP地址的设备可以访问互联网。当内部设备想要进行互联网通信时，它向NAT设备发送请求，NAT设备记录内部IP地址并将其转换为路由器的外部IP地址。

DHCP协议是如何动态分配IP地址的？

DHCP（动态主机配置协议）动态地为设备分配IP地址。当设备连接到使用私有IP地址的局域网时，它会向DHCP服务器请求IP地址，DHCP服务器随后为该设备分配一个在特定租期内使用的IP地址。

IP协议如何帮助数据包在互联网上导航？

IP（互联网协议）像是一个旅行指南，帮助数据包知道它们要去哪里，即目的地和它们的来源。它通常与TCP协议配对使用，形成TCP/IP协议，确保数据包能够正确地从源头传输到目的地。

TCP协议中的三次握手过程是什么？

三次握手是TCP连接开始时的一个过程，确保客户端和服务器准备好开始交换数据。它包括SYN（同步序列编号）包来启动连接，SYN-ACK（同步-确认）包作为响应，以及ACK（确认）包来确认连接的开始。

UDP协议与TCP协议相比有什么不同？

UDP（用户数据报协议）与TCP（传输控制协议）相比，不关心每个数据包的确认交付，因此它更轻量级、更快，适合对速度要求高而不必确保每个数据包都完美传输的应用，如流媒体音乐或视频。

ARP协议在网络中有什么作用？

ARP（地址解析协议）在以太网中充当翻译器，它的工作是将逻辑的IP地址与物理的MAC地址匹配起来，确保网络设备如路由器、网关和交换机能够正确地将流量路由到目的地。

DNS协议如何帮助我们浏览互联网？

DNS（域名系统）通过将人类容易记忆的域名转换为互联网路由使用的语言——IP地址，帮助我们导航互联网。这样，用户只需记住域名，而不需要记住复杂的IP地址。

FTP协议是如何工作的？

FTP（文件传输协议）遵循客户端-服务器架构，允许客户端从服务器请求文件，服务器则提供所请求的文件。FTP通过TCP/IP协议套件运行，确保网络间可靠的数据传输。

SMB协议允许哪些类型的资源共享？

SMB（服务器消息块）协议允许计算机在局域网上共享文件、打印机和其他资源。客户端计算机通过TCP/IP或NetBIOS连接到服务器，一旦连接，客户端可以发送命令来访问共享文件夹、读取或写入文件，甚至使用共享打印机。

SMTP协议在电子邮件传输中扮演什么角色？

SMTP（简单邮件传输协议）是电子邮件传输的基础协议，负责将电子邮件从一个用户移动到另一个用户。尽管SMTP最初在1983年被标准化，但它仍然是今天用于发送电子邮件的主要协议。

SNMP协议的主要功能是什么？

SNMP（简单网络管理协议）是互联网协议套件的一部分，专门设计用于管理计算机和网络设备。SNMP允许计算机和网络设备相互通信和共享信息，以确保网络的顺畅运行。

为什么TELNET协议不再广泛使用？

TELNET协议由于缺乏适合当代技术和通信的强大的安全特性，不再广泛使用。它以明文传输数据，包括登录凭证，容易受到恶意行为者的拦截，因此现代安全的远程访问协议如SSH（安全外壳协议）已经取代了TELNET。

HTTP协议如何支持现代网络应用？

HTTP（超文本传输协议）是互联网的核心技术，作为网络应用的主要通信协议。最初设计用于检索静态网页，HTTP已经演变以支持我们今天常用的复杂网络应用。它基于消息模型，客户端发送请求到服务器，服务器响应相应的响应。

Outlines

00:00

🌐 网络协议基础与IP地址

本段介绍了网络协议的重要性，特别是IP地址，它们是数字世界的基础，允许设备进行电子邮件、视频聊天、观看YouTube视频、发送推文和浏览网页等活动。讨论了公网和私网IP地址的区别以及NAT（网络地址转换）设备如何使本地网络中的设备通过共享的公网IP地址访问互联网。此外，还介绍了DHCP（动态主机配置协议），它动态地为设备分配IP地址，以及IP数据包的结构和TCP/IP协议的工作原理。

05:00

📦 IP数据包结构与TCP协议

这一段深入探讨了IP数据包的头部信息，包括版本、互联网头部长度、类型服务、总长度、标识、IP标志和片偏移等字段。接着，详细解释了TCP（传输控制协议）头部的关键字段，如源端口和目的端口、序列号、确认号、TCP标志、窗口大小、校验和以及紧急指针。此外，还讨论了TCP的三次握手过程以及UDP（用户数据报协议）与TCP的不同之处，强调了UDP在不需要确保每个数据包都可靠传输的应用中的高效性。

10:01

🔍 ARP协议与DNS的作用

ARP（地址解析协议）负责将IP地址映射到MAC地址，这对于以太网上的设备通信至关重要。DNS（域名系统）作为互联网导航的关键部分，负责将人类易于记忆的域名转换为计算机使用的IP地址。DNS使得我们能够通过域名而非复杂的IP地址来访问网站。同时，段落还提到了DNS的安全性问题，包括DNS扫描和DNS欺骗攻击，以及FTP（文件传输协议）的基本工作原理和SMB（服务器消息块）在文件共享和打印服务中的应用。

15:01

📬 SMTP与SNMP协议

SMTP（简单邮件传输协议）是处理电子邮件传输的核心协议，自1983年标准化以来，至今仍在使用。SNMP（简单网络管理协议）是网络设备管理的关键部分，允许设备互相通信并共享信息。然而，SNMP的安全性问题使其成为攻击者的目标，攻击者可能会利用SNMP获取网络信息，甚至控制关键网络设备。

20:03

🔗 Telnet、HTTP与网络协议概述

Telnet是一种远程连接协议，允许用户在远程端点和主机机器之间建立连接。但由于其安全性不足，目前已被更安全的SSH（安全外壳协议）所取代。HTTP（超文本传输协议）是互联网上用于网页应用的主要通信协议，支持复杂web应用的数据传输。视频最后概述了这些协议的重要性，并鼓励观众在评论中提出对特定协议的兴趣，以便制作更多相关内容。

Keywords

💡网络协议

网络协议是计算机网络中数据交换的规则和标准。在视频中，网络协议是核心主题，涵盖了从IP地址到HTTP等多个协议，它们共同构成了数字世界通信的基础。例如，IP地址允许设备互相通信和连接，类似于家庭地址，而TCP/IP协议则确保数据包在源和目的地之间可靠传输。

💡IP地址

IP地址是分配给网络中每个设备的独一无二的标识符，类似于家庭地址，使得设备能够相互通信。视频中提到，每个数字设备，无论是电脑、笔记本、手机还是平板电脑，都会被分配一个IP地址。IP地址分为公网IP和私网IP，私网IP在局域网内使用，而公网IP则用于互联网上的通信。

💡NAT（网络地址转换）

NAT是一种将私网IP地址转换为公网IP地址的技术，允许局域网内多个设备共享一个公网IP地址来访问互联网。视频中解释了NAT设备如何记录内部IP地址，并将其转换为路由器的外部IP地址，以便设备能够进行互联网通信。

💡DHCP（动态主机配置协议）

DHCP是一种网络协议，能够动态地为网络中的设备分配IP地址。视频中提到，DHCP常用于局域网，其中私网IP地址被使用。当设备加入局域网时，它会向DHCP服务器请求IP地址，服务器则为设备分配一个在特定租约期内使用的IP地址。

💡TCP（传输控制协议）

TCP是一种面向连接的、可靠的、基于字节流的传输层通信协议。视频中解释了TCP如何通过三次握手建立连接，并确保数据包的顺序和完整性。TCP协议通过序列号、确认号和标志位等关键字段来管理数据传输，对于网络安全和数据完整性至关重要。

💡UDP（用户数据报协议）

UDP是一种无连接的传输层协议，它允许应用程序发送数据而不需要建立专门的连接。与TCP不同，UDP不保证数据包的顺序或完整性，因此它更快但不那么可靠。视频中提到，UDP适用于对速度要求高而对数据包丢失不太敏感的应用，如流媒体服务。

💡ARP（地址解析协议）

ARP用于将网络层的IP地址解析为数据链路层的MAC地址。视频中描述了ARP如何在局域网内工作，通过广播询问来匹配IP地址和MAC地址，以确保数据能够被正确地路由到目的地。ARP是网络设备如路由器、网关和交换机正确路由流量的关键。

💡DNS（域名系统）

DNS是互联网上用于将域名转换为IP地址的系统。视频中强调了DNS的重要性，它使得用户不必记忆复杂的IP地址，而是可以通过易于记忆的域名来访问网站。DNS是互联网导航的基础，它将人类可读的域名转换为计算机可以理解的IP地址。

💡FTP（文件传输协议）

FTP是一种用于在网络上传输文件的协议。视频中提到，FTP遵循客户端-服务器架构，允许客户端请求文件，服务器提供文件。FTP使用命令和数据两个通道进行通信，支持下载、上传、编辑、复制和删除文件等操作。尽管FTP在私有和安全文件共享中仍然使用，但其在公共文件共享中的使用已因HTTP的崛起而减少。

💡SMB（服务器消息块）

SMB是一种用于在局域网上共享文件、打印机和其他资源的通信方法。视频中解释了SMB如何允许计算机之间通过TCP/IP或NetBIOS进行通信，以便客户端可以访问服务器上的共享文件夹、打印机等资源。SMB在Windows和Linux/Unix系统中非常重要，但也存在安全漏洞的风险。

💡SMTP（简单邮件传输协议）

SMTP是用于发送电子邮件的互联网标准。视频中指出，尽管SMTP在1983年就被标准化，但它仍然是今天发送电子邮件的基础协议。SMTP作为互联网的邮政服务，确保电子邮件能够从一位用户传送到另一位用户。SMTP是数字世界中处理电子邮件的关键协议。

Highlights

网络协议是数字世界的基础，对于使用Wireshark等工具至关重要。

IP地址是网络通信的核心，类似于家庭地址，使设备能够相互连接和通信。

IPv4系统有43亿个IP地址，不足以覆盖所有需要连接互联网的设备。

私有IP地址在局域网内重复使用，通过NAT设备转换为公共IP地址以访问互联网。

DHCP协议动态分配IP地址，有助于管理和优化网络中可用的IP地址。

IP协议帮助数据包在互联网上知道目的地和来源，常与TCP协议配对使用。

IP数据包头部包含版本、头部长度、服务类型等关键信息。

TCP协议通过三次握手建立稳定连接，确保数据包的顺序和可靠传输。

TCP头部包含源端口、目的端口、序列号等重要字段，对网络分析至关重要。

UDP协议与TCP不同，不建立正式连接，直接发送数据包，适用于对速度要求高的应用。

ARP协议将IP地址映射到MAC地址，对以太网设备正确路由流量至关重要。

DNS协议将人类易于记忆的域名转换为计算机友好的IP地址。

FTP协议用于网络间文件传输，遵循客户端-服务器架构。

SMB协议允许计算机在局域网内共享文件、打印机和其他资源。

SMTP协议是电子邮件传输的基础，负责将邮件从一个用户移动到另一个用户。

SNMP协议用于管理网络设备，允许设备间通信和信息共享。

Telnet协议允许远程连接，但由于其安全性不足，已逐渐被SSH等更安全的协议取代。

HTTP协议是互联网的基础技术，作为主要的网络应用通信协议。

Transcripts

hey everyone today we're talking about

common Network protocols some of you

asked for a full guide on wire shark but

I realized that to use wi shark well you

need to understand Network protocols

first in the hacking World knowing about

Network protocols is essential because

you can't do much without them that's

why I'm making this video to help you

grasp the basics of network protocols

which will set you up for Success when

using tools like wire shark and hacking

let's begin with IP addresses internet

protocol addresses are like the backbone

of the digital world there would allow

us to do things like email video chat on

Zoom watch YouTube send tweets and

browse the web you could say they're

almost as important as the world itself

spinning in fact you're able to watch

this video on YouTube because of IP

addresses every digital device we use

whether it's a computer laptop phone or

tablet gets assigned an IP address this

address enables devices to communicate

and connect with each other think an IP

address as similar to your house address

without it no one would be able to find

you and send you mail now let's discuss

public and private IP addresses our IP

address system has a limitation there

aren't enough IP addresses to cover all

devices that need to connect to the

internet the current ipv4 system has

only 4.3 billion IP addresses which

isn't sufficient considering there are

over 8 billion people on the planet each

with multiple devices to address this

scarcity a system was developed to reuse

a group of IP addresses within a local

area network or Lan which are not

accessible over the Internet these

addresses can be used repeatedly within

each local network helping conserve The

Limited number of IP addresses available

these private addresses typically start

with numbers like

192 168 10 point or

17216 you might have noticed these

private IP addresses such as

192 16 8 or 10 point something when

checking your network configuration for

example using IF config on a collie

system these addresses are only usable

within your local area network and

cannot be used to communicate over the

Internet directly for internet

communication your private IP address

needs to be translated into a public IP

address by a network address translation

ornat device this translation process

allows devices within your local network

to access the internet using a shared

public IP

address this is necessary because

private IP addresses within a local area

network cannot be directly used on the

internet since they are not unique many

lands use the same private IP addresses

internally when a machine inside the

land wants to communicate over the

Internet it sends a request to the natat

device the natat device then records the

internal IP address of the machine in a

table and converts it to the external IP

address of the router when the response

packet returns from its destination on

the the internet the natat device checks

its table and forwards the packet to the

internal IP address of the original

machine within the Lan this whole

process happens seamlessly and

individual systems or users within the

Lan typically don't realize that their

private IP addresses are being

translated to a public IP address by the

natat device to enable internet

communication the next protocol is DHCP

Dynamic host configuration protocol or

DHCP is a protocol that dynamically

assigns IP address add es this means

that instead of having a fixed IP

address all the time your device gets a

new IP address each time it connects to

a network DHCP is commonly used on local

area networks or lands where private IP

addresses are used when a device joins a

lan it sends a request to the DHCP

server asking for an IP address the DHCP

server then assigns an IP address to

that device for a specific period known

as a lease this lease defines how long

the device can use that particular IP

address the interesting part is that

each time you connect to the Lan you're

likely to receive a different Dynamic IP

address although usually within the same

range this Dynamic allocation of IP

addresses by DHCP helps manage and

optimize the use of available IP

addresses within the network all right

let's talk about the next protocol IP or

Internet Protocol in an easy to

understand way IP is like a travel guide

for data packets on the internet it

helps these packets know where to go the

destination and where they're coming

from the source it's often paired up

with other protocols like TCP to form

what's commonly known as TCP IP now

let's take a peek at what's inside an IP

packet header this header is like the

packets ID card carrying information

that can be super useful for someone

exploring hacking or doing forensic

investigations in the first row of this

ID card version it tells us which

version of Ip is being used either V4 or

V6 internet header length this is all

about the length of the header moving on

to the second row type of service or to

this part describes the packet service

type like if it's focused on speed

reliability or cost Effectiveness total

length this tells us the overall size of

the packet including its data in the

third row identification each packet

gets a unique ID helpful for putting

together fragmented packets IP Flags

this field helps us know if the packet

is split into smaller parts or not which

can be sneaky for bypassing security

measures fragment offset if a packet is

split this field tells us where it

starts in the sequence now on to row

four and five Source or destination

these are super important because they

show where the packet is coming from and

where it's headed finally in row six

options this is a flexible part of the

header and it's optional to use padding

if needed this part fills in any extra

space in the header understanding these

details helps in figuring out how data

travels across the internet and can even

give clues about the systems sending and

receiving the data the next protocol is

TCP in the TCP header there are several

important fields that are crucial for

both aspiring hackers and forensic

investigators to grasp starting with row

One Source Port destination Port these

fields are vital as they determine the

source and destination port showing

where the communication is coming from

and where it's headed moving on to row

two sequence number this number is

generated by the sender's TCP stack and

ensures that packets are arranged in the

correct order when they arrive it's also

crucial in preventing man in the middle

attacks next in row three

acknowledgement number this Echoes back

the sequence number confirming that the

packet has been received if no

acknowledgement is received within a set

time the sender resends the packet to

ensure successful delivery this

reliability distinguishes TCP from UDP

which doesn't guarantee packet delivery

skipping ahead to the flags in row four

sin initiates a new connection Finn

signals the normal closing of a

connection a acknowledges receipt of a

packet crucial after the three-way

handshake RSD indicates a hard close of

a connection often used to communicate

errors urg marks urgent data in the

packet PS sh directs the data past the

buffer to the application understanding

these flags is essential especially for

those familiar with Recon tools like

nmap or hping 3 as they're used to

create packets for specific purposes

such as evading detection or eliciting

responses from secure systems in row

four the window siiz field manages

packet buffering aiding in flow control

it's also useful for OS identification

as different operating systems have

varying window sizes allowing for OS

prediction with about 80% accuracy the

cheim in row five ensures data Integrity

while the urg pointer indicates urgent

data if the urg flag is set lastly row

six contains options and padding

allowing for additional information and

aligning the TCP header to a multiple of

32 bits understanding these TCP header

Fields is crucial for analyzing Network

traffic identifying potential security

threats and gaining insights into the

systems communicating over the Network

every TCP connection starts with a

three-way handshake imagine you're

trying to start a conversation with

someone let's say ordering a pizza over

the phone you dial the pizza place and

say hey I'd like to order a pizza this

is like the sin packet where you're

initiating the connection and saying

hello I want to talk to you the pizza

place responds sure we're ready to take

your order this is like the sin act

packet where the server acknowledges

your request and says hi I'm here and

ready to chat let's get started you then

confirm great I'd like a large pepperoni

pizza please this is like the ACT packet

where you acknowledge the server's

response confirming that you're ready to

proceed with the conversation or in this

case the pizza order after this

three-way handshake the pizza place

knows you're ready to place your order

just like in TCP both the client and

server know they're ready to start

exchanging data it's a way of ensuring a

smooth and reliable connection before

diving into the main conversation or

data

transfer let's dive into UDP or user

datagram protocol UDP is a different

kind of Beast compared to TCP while TCP

is all about establishing a solid

connection like a handshake and ensuring

every piece of data gets delivered UDP

takes a more Carefree approach it's like

the difference between sending a formal

letter with tracking TCP versus tossing

a postcard in the male UDP here's what

makes UDP unique unlike TCP which

requires a Formal Connection setup like

the three-way handshake we talked about

earlier UDP doesn't bother with all that

it just sends packets out into the world

without worrying about getting a

confirmation of delivery because UDP

skips the whole connection Assurance

process it's lighter and faster than TCP

this makes it perfect for applications

where speed matters more than ensuring

every single packet gets through

perfectly UDP shines in scenarios where

efficiency is key and losing an

occasional packet isn't a big deal think

of streaming music or video missing a

few seconds here or there won't ruin

your experience but lagging behind

because of a slow connection would

definitely be a problem some of the key

protocols that use UDP include DNS SNMP

or ntp we'll dive deeper into these

protocols later on now let's talk about

the next protocol a RP or address

resolution protocol ARP is like a

translator for devices on an Ethernet

Network

its job is to match up IP addresses

which are logical with Mac addresses

which are physical this way when a new

device joins the network ARP assigns it

an IP address within the Network's range

and links it to its unique Mac address

this information is crucial for network

devices like routers gateways and

switches to correctly Route traffic to

the intended destination now here's how

the RP Works in simple terms imagine you

have two computers on the same ethernet

Network let's call them computer 1 and

computer 2 computer 1 wants to send a

message to computer 2 but it needs to

know computer 2's Mac address like a

home address computer one first checks

its ARP table which is a list of known

Mac addresses and their corresponding IP

addresses if it finds computer 2's Mac

address in the table great it can send

the message directly if computer 1

doesn't have computer 2's Mac address in

its ARP table it sends out a broadcast

message to all devices on the network

nwor asking hey who has IP address of

this computer 2 sees the broadcast

message and responds directly to

computer 1 saying I have IP address of

this and my Mac address is this now that

computer 1 knows computer 2's Mac

address it can send the message directly

to computer 2's Mac address and the

communication is successful ARP is

essential for smooth communication

within a network but it's also a

potential Target for attackers who might

try to manipulate Ark messages to

intercept or redirect Network traffic a

tactic known as a man in the- Middle

attack it's important to note that a RP

lacks authentication making it

vulnerable to exploitation by hackers

this feature can be used to discover all

the systems on a network easily this

becomes particularly useful when

attempting to hack into another system

within the local area network or when a

hacker compromises a single user on the

network and wants to Pivot to a more

valuable Target such as a database

server there are various tools available

to hackers for discovering systems on a

network these tools operate by sending

out gratuitous ARP requests prompting

systems on the network to respond with

their IP addresses and Mac addresses for

example in our Collie system we have a

tool called net discover that can be

used for this

purpose

now the next protocol is denas the

domain name system or DNS is a

fundamental protocol that plays a

crucial role in how we navigate the

internet imagine a world without DNS we

would have to remember countless IP

addresses just to access our favorite

websites picture having to memorize the

lengthy ipv4 32-bit addresses for Google

Facebook YouTube and other essential

sites let alone dealing with even longer

IPv6 128bit addresses it would be quite

a daunting task thankfully DNS comes to

the Rescue by translating domain names

something humans are good at remembering

into IP addresses the language of

internet routing in simpler terms DNS is

like a translation service that converts

a domain name like wwwg googlec into the

computer friendly IP address that the

internet understands and uses to Route

data so when you type a domain name into

your browser such as www googlec DNS

steps in behind the scenes to quickly

translate it into the corresponding IP

address allowing your device to connect

to the desired website seamlessly DNS is

what makes navigating the internet so

much easier and userfriendly for all of

us the domain name system has come a

long way in terms of security but it

used to be quite fragile and susceptible

to attacks while improvements have been

made over the years attacks on DNS still

occur albeit less frequently one common

type of attack involves harvesting

information from DNS servers on the

target Network a technique known as DNS

scanning and DNS reconnaissance

attackers can gather valuable data from

DN servers such as domain names and

Associated IP addresses which can be

used for further

exploitation on local area networks

attackers May exploit DNS

vulnerabilities by spoofing DNS

responses using tools like DNS spoof

this allows them to redirect client

traffic to a malicious local system

controlled by the attacker for example

an attacker could redirect banking

traffic to their own fraudulent website

capturing sensitive credentials and

financial

information the next protocol is FTP or

file transfer protocol the FTP is a

client server protocol used for

transferring files over a network here's

an overview of how FTP works and its

current usage FTP follows a client

server architecture where a client such

as a computer or device requests files

from a server and the server provides

the requested files FTP operates over

the TC pip Suite of protocols ensuring

reliable data transmission across

networks FTP uses two channels for

communication command Channel used by

the client to send commands to the

server such as requesting files or

directories data Channel used for actual

file transfers when a client requests a

file the server opens a data channel to

transfer the file to the client clients

can perform various actions on files

using FTP including downloading

uploading editing copying and deleting

files on the server while FTP was widely

used in the past for file sharing and

management its popularity has decreased

with the rise of HTTP for file transfers

especially for public file sharing on

the web however FTP remains a common

protocol for private and secure file

sharing such as in banking system or

other environments where data security

and privacy are

Paramount the next protocol we'll talk

about is SMB which stands for Server

message Block it's a communication

method that computers use to share files

printers and other resources over a

local network think of it as a way for

computers to talk to each other and

share stuff when you use SMB one

computer acts as the server that has the

files or printers others want to access

while the other computers are the

clients that want to get those files or

use the printers here's how it works in

simple steps clients computers connect

to servers other computers using tcpip

or

netbios which are just ways for

computers to talk to each other over a

network once connected clients can send

commands to the server to access shared

folders where files are stored read or

write files or even use shared printers

basically SMB lets you do on your

computer what you normally do like

access ing files or printing but over

the network so you can share things with

others on the same network SMB in

Windows and Samba in Linux Unix systems

have historically been significant

sources of critical vulnerabilities and

this trend is likely to continue in the

future over the past decade there have

been several critical vulnerabilities

related to SMB and windows these

vulnerabilities have allowed attackers

to send specially crafted packets to SMB

Services exploiting weaknesses in the

protocol by exploiting these

vulnerabilities attackers could execute

remote code with system privileges on

the target system in simpler terms

attackers could take control of

vulnerable systems and have full access

to everything on them the next protocol

we'll discuss is the simple male

transport protocol commonly abbreviated

as SMTP SMTP is a crucial protocol in

the digital world especially for

handling emails snp's main job is to

move emails from one user to another

even though SMTP was first standardized

back in 1983 it's still the fundamental

protocol used for sending emails today

albeit with some Modern upgrades and

improvements in simple terms SMTP acts

as the Postal Service of the internet

ensuring that your emails get delivered

the next protocol we'll look at is SNMP

which stands for simple Network

management protocol SNMP is a crucial

part of the Internet Protocol Suite

designed specifically for managing

computers and Network devices in simpler

terms SNMP allows computers and network

devices to communicate and share

information with each other it's like a

system of Administrators managers

keeping an eye on a group of computers

or devices agents to ensure everything

runs smoothly indeed the simple Network

management protocol SNMP is often

overlooked but plays a crucial role in

maintaining a smoothly functioning

Network however its importance also

makes it a prime target for attackers if

an attacker manages to breach SNMP they

gain access to a wealth of information

about your network they can potentially

decrypt encrypted VPN Communications

allowing them to eases drop on sensitive

data being transmitted additionally they

can view and potentially manipulate

every device connected to your network

SNMP operates on UDP ports 161 and 162

enabling network devices to communicate

with each other and allowing

administrators to manage and monitor

these devices however in the wrong hands

SNMP access can lead to disastrous

consequences attackers could Harvest

sensitive information disrupt network

operations or even take control of

critical devices like routers and

switches causing widespread Havoc the

next protocol is telnet telnet is a

protocol designed for remote

connectivity allowing a user to

establish connections between a remote

endpoint and a host machine to initiate

a remote session when a connection is

established tnet Pro prompts the user at

the remote endpoint to log in once

authenticated telnet grants the endpoint

access to network resources and data

located on the host computer originating

from the 1960s telnet can be considered

one of the earliest versions of remote

communication protocols used in the

development of the modern internet

however due to its lack of robust

security features suitable for

contemporary technology and

Communications telnet is no longer

widely used the main reason for Tel

Net's declining usage is its

vulnerability to security threats talet

transmits data including login

credentials in plain text making it

susceptible to interception by malicious

actors consequently modern secure

protocols such as SSH or secure shell

have largely replace telnet for remote

access due to their enhanced security

features such as encryption and stronger

authentication

mechanisms the next is HTTP protocol the

hypertext transfer protocol or http p is

a foundational technology of the

internet serving as the primary

communication protocol for web

applications originally designed for

retrieving static web pages HTTP has

evolved over time to support complex web

applications that we commonly use today

HTTP operates on a message-based Model

where a client sends a request to a

server and the server responds with a

corresponding response it's important to

note that HTTP is connectionless meaning

that a connection is established and

closed for each request response cycle

however it uses TCP transmission control

protocol as its underlying transport

mechanism for Reliable data transmission

in essence HTTP is the backbone that

enables seamless communication between

clients such as web browsers and servers

facilitating the transfer of web pages

data and multimedia content across the

internet hey everyone in this video we

covered some of the most used and

essential Network protocols while we

didn't dive deep into each protocol I

hope this overview helped you understand

their significance in networking if

you're interested in learning more about

any specific protocol feel free to drop

a comment below I'll consider your

requests for future videos and create

content that addresses your specific

interests and I am making video on wi

shark until then make sure to watch this

video and stay tuned for more

informative content on network protocols

and tools thanks for watching and I'll

see you in the next video

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