Internet & Network Attacks

• Personal data theft
• Ransomware
• Malicious links

What is Network ???

A network is defined as a group of two or more computer systems linked together. There are many types of computer networks, including the following:

• local-area networks (LANs): The computers are geographically close together (that is, in the same building).
• wide-area networks (WANs): The computers are farther apart and are connected by telephone lines or radio waves.
• campus-area networks (CANs): The computers are within a limited geographic area, such as a campus or military base.
• metropolitan-area networks ( MANs): A data network designed for a town or city.
• home-area networks (HANs): A network contained within a user's home that connects a person's digital devices.

What is network Management ???

• Network management is the process of administering and      managing  the computer networks of one or many organisations.
• Network management refers to the broad subject of managing computer networks.

IP Address(Internet Protocol address)

•  Internet Protocol address, an IP or IP address is a number used to indicate the location of a computer or other device on a network using TCP/IP.
• Example:- 172.16.166.10

      Type of IP address:-

• A class ( 0-127)           [n . h . h . h]
• B class (128-191)       [n . n . h . h]
• C class (192-223)       [n . n . h .h]
• D class (224-234)
• E class (240-255

network

Host

Network & Broad Cast address

• 172.16.166.10

                                                                                   Network address : 172.16.0.0

                                                                        Broad cast address : 172.16.255.255

                    

                                    Private IP Address:- 

                           1.  A class:- 10.*.*.*                 

                                          2.  B class :- 172.16.*.*   to 172.31.*.*

3. 192.168.*.*

Rest all IP address public

OSI Model

         ( Open Systems Interconnection )

       :: 7 layers in OSI model :-

        1. Application layer

        2. Presentation layer

        3. Session layer

        4. Transport layer

        5. Network layer

        6. Data link layer

        7. Physical layer

1. Physical layer:- This layer define the hardware equipment, cabling, wiring,  cabling,                                                        wiring, frequencies, pulse used to represent binary signals etc. physical                                                  layer provides its services to Data-link layer.

2. Data link layer:- This layer is the protocol layer that transfers data between adjacent                                                         network nodes in a wide area network (WAN) or between nodes on                                                        the same local area network (LAN) segment.

 

                           

 

 

 

Data link layer

                  LLC

(Logical link control )

                                        MAC

                                              (Media access control)

3. Network layer :-  Network layer that  provides data routing   paths for                                             network communication.

​ 4. Transport layer :- It  is responsible for end-to-end communication over a network.

​ 5. Session layer :- The session layer provides the mechanism for opening,                                      closing and managing a session between end-user                                              application processes.

 6. Presentation layer :- Presentation layer is serves as the data translator                                    for the network. It is sometimes called the syntax layer.

  7. Application :-It consists of protocols that focus on process-to-process communication                                               across an IP network and provides a  firm communication interface and                                                 end-user services.

SOME PORT NUMBERS

Introduction

•  Phishing is the act of attempting to acquire information such as    username, password and money card details as a trustworthy  entity in an electronic communication.

• Types :- Malware-based, DNS-based, Key-loggers, Screen-loggers etc.

• Gophish.                                                                                                              

Introduction

• Wireshark is an open source software project, and is released under the GNU General Public License.

• Wireshark is a network packet analyzer.                                              

• Its originally named Etheral.                                                                   

PURPOSE & FEATURES

• Capture live packet data from a network interface, Display packets with very detailed protocol information, Search for packets on many criteria.
• And many more…

 

 

 

 

 

 

• It is used for network troubleshooting, analysis, software and communication protocol development.
• A lot more…                                                 

Where we get, How installation & use ?

• WWW.WIRESHARK.ORG
• apt-get install Wireshark

 

 

 

Introduction

• Cryptography comes from Greek kryptós “hidden” + gráphein “write”.
• Cryptography is the practice and study of techniques for secure communication in the presence of third parties (called adversaries).

• Symmetric                                                                           

              •  Same key is used by both parties

• Key distribution problem

• Asymmetric                                                                        

                           •  Key pairs for encryption and decryption

                                      •  Public and Private Keys

 

 

 

 

TYPES

Examples and Questions

Decrypt it :- 4 6 7 11 2 9 3 2

Browser Security

"Our Best friend and worst enemy"

 Exploiting Browser
 

Malicious javacript can be used in different ways to
compromise user's data and privacy.

Stegosploit

Tips for secure browsing

• Enable phishing and malware protection
• Configure content settings
• Cookies
• JavaScript
• Pop-ups
• Location

Resources Link :

• https://en.wikipedia.org/
• https://ctftime.org/
• https://www.wireshark.org/
• https://haveibeenpwned.com/
• https://picoctf.com

Thank you