Book Image

CCNA Security 210-260 Certification Guide

By : Glen D. Singh, Michael Vinod, Vijay Anandh
Book Image

CCNA Security 210-260 Certification Guide

By: Glen D. Singh, Michael Vinod, Vijay Anandh

Overview of this book

With CCNA Security certification, a network professional can demonstrate the skills required to develop security infrastructure, recognize threats and vulnerabilities to networks, and mitigate security threats. The CCNA Security 210-260 Certification Guide will help you grasp the fundamentals of network security and prepare you for the Cisco CCNA Security Certification exam. You’ll begin by getting a grip on the fundamentals of network security and exploring the different tools available. Then, you’ll see how to securely manage your network devices by implementing the AAA framework and configuring different management plane protocols. Next, you’ll learn about security on the data link layer by implementing various security toolkits. You’ll be introduced to various firewall technologies and will understand how to configure a zone-based firewall on a Cisco IOS device. You’ll configure a site-to-site VPN on a Cisco device and get familiar with different types of VPNs and configurations. Finally, you’ll delve into the concepts of IPS and endpoint security to secure your organization’s network infrastructure. By the end of this book, you’ll be ready to take the CCNA Security Exam (210-260).
Table of Contents (19 chapters)

Hashing algorithms

As mentioned previously, in the computing world it a bit challenging for us humans to prove the integrity of a message. We use hashing algorithms to assist us in determining the integrity of a message. In this section, we're going to take a look at the two main hashing algorithms being used today, which are MD5 and SHA:

Why do we need to validate the integrity of a message? Let's assume that there are two people, Bob and Alice. They would both like to communicate over a network. Alice wants to send Bob a message, but Bob is also concerned that the message may be altered before it arrives at his end. To help Bob determine if the message was altered during transmission or not, Alice would need to create a cryptographic hash of the message and send both the message and the hash values to Bob:

When Bob receives the message, Bob also creates a cryptographic...