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Network Security Overview

In this guide, we present a list of the possible attack types that can occur in communication between two parties, as well as the two possible network security models.

Types of Attacks

  • We can divide possible attacks into two types:

Passive Attacks​

  • Listen attack (information disclosure):


Fig.1: Example of an information disclosure listen attack

  • Listen attack (traffic analysis):


Fig.2: Example of a traffic analysis listen attack

Active attacks​

  • Tampering attack:


Fig.3: Example of a tampering attack

  • Impersonation attack:


Fig.4: Example of an impersonation attack

  • Replay attacks:


Fig.5: Example of a replay attack

  • DDOS (denial of service attacks):


Fig.6: Example of a denial of service attack (Bob and other legitimate users cannot access the web server)

Network Security Models

  • There are two network security models:

1. Gateway​

  • E.g.: Firewall


Fig.7: Example of a security model using a firewall

2. Secure Channel​

  • E.g.: TLS/SSL


Fig.8: Diagram of how a secure channel works