Book Image

Practical Network Scanning

By : Ajay Singh Chauhan
Book Image

Practical Network Scanning

By: Ajay Singh Chauhan

Overview of this book

Network scanning is the process of assessing a network to identify an active host network; same methods can be used by an attacker or network administrator for security assessment. This procedure plays a vital role in risk assessment programs or while preparing a security plan for your organization. Practical Network Scanning starts with the concept of network scanning and how organizations can benefit from it. Then, going forward, we delve into the different scanning steps, such as service detection, firewall detection, TCP/IP port detection, and OS detection. We also implement these concepts using a few of the most prominent tools on the market, such as Nessus and Nmap. In the concluding chapters, we prepare a complete vulnerability assessment plan for your organization. By the end of this book, you will have hands-on experience in performing network scanning using different tools and in choosing the best tools for your system.
Table of Contents (19 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Firewall and design considerations


Security is the most important consideration for any secure network design. There are many ways to secure the network, and firewall techniques are one of the most important ways to implement network security.

The term firewall was in use as early as 1764 to describe walls that isolate the parts of a building most likely to have a fire (for example, a kitchen) from the rest of a structure. There are two types of firewalls: one is based on hardware, and the second is based on software. Hardware-based firewalls are dedicated hardware units used to protect a piece of network or segment, while software-based firewalls run on top of the operating system to protect host machines.

A firewall protection strategy totally depends on the expertise of a firewall administrator and the efficiency of firewall hardware. Security rules and management policies are the most critical tasks for access control policies. IP communication is based on five basic tuples, and for each...