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

How to perform host discovery


One of the basic techniques of identifying a running host is by sending an ICMP ping packet and analyzing the response to draw a conclusion. What if the host or the network is blocking ICMP packets at the network level or the host level? As per the ICMP technique, the host or the network will not pop up in the live host list. Host discovery is one of the core components of a network penetration test or vulnerability scan. A half-done host discovery can ignore hosts or networks from the scope and perform any further operation, thus leaving the network vulnerable.

Nmap provides various options and techniques to identify the live host by sending customized packets to satisfy specific network conditions. If no such options are provided, Nmap by default sends an ICMP echo to identify the live hosts. The provided probe options can be combined to increase the odds of identifying further ports. Once Nmap probes for the live hosts and obtains a list of live hosts, it...