Guide to SSL VPNs
Secure Sockets Layer (SSL) virtual private networks (VPN) provide secure remote
access to an organization’s resources. A VPN is a virtual network, built on top of
existing physical networks, that can provide a secure communications mechanism for data
and other information transmitted between two endpoints. Because a VPN can be used over
existing networks such as the Internet, it can facilitate the secure transfer of
sensitive data across public networks. An SSL VPN consists of one or more VPN devices
to which users connect using their Web browsers. The traffic between the Web browser
and the SSL VPN device is encrypted with the SSL protocol or its successor, the
Transport Layer Security (TLS) protocol. This type of VPN may be referred to as either
an SSL VPN or a TLS VPN.
This guide uses the term SSL VPN. SSL VPNs provide remote users with access to Web
applications and client/server applications, and connectivity to internal networks.
Despite the popularity of SSL VPNs, they are not intended to replace Internet Protocol
Security (IPsec) VPNs.1 The two VPN technologies are complementary and address separate
network architectures and business needs. SSL VPNs offer versatility and ease of use
because they use the SSL protocol, which is included with all standard Web browsers, so
the client usually does not require configuration by the user. SSL VPNs offer granular
control for a range of users on a variety of computers, accessing resources from many
locations.
This publication discusses the fundamental technologies and features of SSL VPNs. It
describes SSL and how it fits within the context of layered network security. It
presents a phased approach to SSL VPN planning and implementation that can help in
achieving successful SSL VPN deployments. It also compares the SSL VPN technology with
IPsec VPNs and other VPN solutions. This information is particularly valuable for
helping organizations to determine how best to deploy SSL VPNs within their specific
network environments.
The attached Zip file includes:
Intro Page.doc
- Cover Sheet and Terms.doc
- Guide to SSL VPNs.pdf