tailieunhanh - Introduction to VPNs, PKI, and PGP

Hello, in this module we continue our discussion of encryption and we look at some practical applications of it. We start off by looking at VPN’s or virtual private networks and see how you can use them to create secure communications using public networks such as the Internet. We than briefly look at the problem of key management and finish our discussion with a look at PGP or Pretty Good Privacy, which is an application that allows you to encrypt files and send encrypted email. | Introduction to VPNs PKI and PGP Security Essentials The SANS Institute Encryption and Exploits - SANS 2001 1 Hello in this module we continue our discussion of encryption and we look at some practical applications of it. We start off by looking at VPN s or virtual private networks and see how you can use them to create secure communications using public networks such as the Internet. We than briefly look at the problem of key management and finish our discussion with a look at PGP or Pretty Good Privacy which is an application that allows you to encrypt files and send encrypted email. 3 - 1 Foundations of a VPN VPNs use cryptography to communicate securely in the presence of adversaries - Encryption Scramble data into something difficult to read without a key. - Decryption the opposite process of encrypting. - Authentication How are you sure you re talking to the right person VPNs PKI and PGP - SANS 2001 2 To architect and deploy a VPN we need to understand how to apply these three tools. These concepts are easy to grasp at the conceptual level but the devil is in the details as they say. Crypto has evolved from an abstract playground for mathematicians to something with widespread public awareness those little solid gold keys in the browser have people asking the darndest questions . Likewise authentication is a discipline in its own right. We ll be discussing authentication systems and client-side web certificates. 3 -2 What is a VPN Dedicated leased lines are expensive Most locations have low-cost connectivity to the Internet Why not use the Internet as the communication media and use encryption for security So a VPN is a secure communication path that utilizes public networks VPNs PKI and PGP - SANS 2001 3 In its most basic sense VPN s or virtual private networks are a secure communication path that utilizes public networks. Having dedicated leased lines between locations provides for secure communications but can get very expensive. With most leased lines you