Book Image

SSL VPN : Understanding, evaluating and planning secure, web-based remote access

Book Image

SSL VPN : Understanding, evaluating and planning secure, web-based remote access

Overview of this book

Virtual Private Networks (VPNs) provide remote workers with secure access to their company network via the internet by encrypting all data sent between the company network and the user?s machine (the client). Before SSL VPN this typically required the client machine to have special software installed, or at least be specially configured for the purpose. Clientless SSL VPNs avoid the need for client machines to be specially configured. Any computer with a Web browser can access SSL VPN systems. This has several benefits: Low admin costs, no remote configuration Users can safely access the company network from any machine, be that a public workstation, a palmtop or mobile phone By pass ISP restrictions on custom VPNs by using standard technologies SSL VPN is usually provided by a hardware appliance that forms part of the company network. These appliances act as gateways, providing internal services such as file shares, email servers, and applications in a web based format encrypted using SSL. Existing players and new entrants, such as Nokia, Netilla, Symantec, Whale Communications, and NetScreen technologies, are rushing our SSL VPN products to meet growing demand. This book provides a detailed technical and business introduction to SSL VPN. It explains how SSL VPN devices work along with their benefits and pitfalls. As well as covering SSL VPN technologies, the book also looks at how to authenticate and educate users ? a vital element in ensuring that the security of remote locations is not compromised. The book also looks at strategies for making legacy applications accessible via the SSL VPN.
Table of Contents (14 chapters)
SSL VPN
Credits
About the Authors
Introduction
A Review of TCP, IP, and Ports

Authentication and Authorization


As discussed in Chapter 3, SSL VPNs typically require that users identify themselves and prove their identities before granting access to internal resources.

Authentication

Authentication is usually achieved using one or more of the following factors:

  • Something only the user knows

  • Something only the user has

  • Something only the user is (i.e., a physical property of the user's person)

SSL VPN products support a variety of authentication schemes and leverage all three of the aforementioned methods of proving one's identity. Most commonly, users identify themselves using a username and authenticate using one of these several techniques:

Passwords

The user is supplied a secret password known only to the user and which is associated with the user's identification information (username). The SSL VPN compares this password to a copy of the password stored in a database or preferably performs a hash on the password and compares it to a previously hashed value of the correct...