Unformatted text preview: tected in the TLS Handshake Protocol, the detecting party sends an alert
message to the other party. The SSL Record layer supports alert messages that convey information
about the status of the connection. There are two types of alerts: Fatal and Warning. A Fatal alert
message indicates that the connection is so bad that it needs to be terminated immediately. A
Warning alert message indicates that there are some problems in the connection. Like other
messages, alert messages are enciphered and compressed, as specified by the current connection
state. 48 VPN, IPSec and TLS SSL VPN
SSL VPN Gateway
• File Transfer Internet
SSL (TLS) Secure Connection S
Address Translation Kiosk •
• Provides secure remote access to corporate applications.
Uses SSL & TTL as the underlying transport to establish a secure session
between any web browser and the proxy server in the SSL VPN Gateway.
Presents users with a web portal containing links to applications.
Functions as a proxy for both client (web browser) and server (web server) –
there is never a direct connection to the private network.
Ensures that authorized users have access only to specific resources as
allowed by the company security policy implemented by the proxy server and
integrated traffic management.
VPN IPsec IKE v2 TLS M. Mogollon – 01/08 - 49 • An SSL VPN uses SSL and proxy technology to provide authorized and secure access for endusers to HTTP, client/server, and file sharing resources. SSL VPNs use SSL & TTL as the
underlying transports to establish a secure session between any Web browser and the proxy server
in the SSL VPN Gateway. It functions as a proxy for both client (Web browser) and server (Web
server) – there is never a direct connection to the private network. The proxy technology in SSL
VPNs gives a Web browser access to applications that SSL alone doesn’t provide.
• In a SSL VPN (proxy server), two connections are established: one between the Web browser in