Book Image

Securing Network Infrastructure

By : Sairam Jetty, Sagar Rahalkar
Book Image

Securing Network Infrastructure

By: Sairam Jetty, Sagar Rahalkar

Overview of this book

Digitization drives technology today, which is why it’s so important for organizations to design security mechanisms for their network infrastructures. Analyzing vulnerabilities is one of the best ways to secure your network infrastructure. This Learning Path begins by introducing you to the various concepts of network security assessment, workflows, and architectures. You will learn to employ open source tools to perform both active and passive network scanning and use these results to analyze and design a threat model for network security. With a firm understanding of the basics, you will then explore how to use Nessus and Nmap to scan your network for vulnerabilities and open ports and gain back door entry into a network. As you progress through the chapters, you will gain insights into how to carry out various key scanning tasks, including firewall detection, OS detection, and access management to detect vulnerabilities in your network. By the end of this Learning Path, you will be familiar with the tools you need for network scanning and techniques for vulnerability scanning and network protection. This Learning Path includes content from the following Packt books: •Network Scanning Cookbook by Sairam Jetty •Network Vulnerability Assessment by Sagar Rahalkar
Table of Contents (28 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Passive information gathering


Passive information gathering is a technique where no direct contact with the target is made for gathering the information. All the information is obtained through an intermediate source which may be publicly available. The internet has many useful resources that can help us with passive information gathering. Some such techniques are discussed next.

The following diagram describes how passive information gathering works:

Here is how it works:

  1. The client system first sends a request to an intermediate system
  2. The intermediate system probes the target system
  3. The target system sends the result back to the intermediate system
  4. The intermediate system forwards it back to the client

So, there's no direct contact between the client and the target system. Hence, the client is partially anonymous to the target system.

Reverse IP lookup

Reverse IP lookup is a technique that is used to probe any given IP address for all the domains it hosts. So all you need to do is feed the target...