070-649 Free Dumps Study Materials
Question 10: You deploy a Windows Server 2008 R2 VPN server behind a firewall. Remote users connect to
the VPN by using portable computers that run Windows 7.
The firewall is configured to allow only secured Web communications.
You need to enable remote users to connect as securely as possible. You must achieve this goal
without opening any additional ports on the firewall.
What should you do?
A. Create an SSTP VPN connection.
B. Creates a PPTP VPN connection.
C. Create an L2TP VPN connection.
D. Create an IPsec tunnel.
Correct Answer: A
Explanation:
Secure Socket Tunneling Protocol (SSTP) is a tunneling protocol that uses the HTTPS protocol over
TCP port 443 to pass traffic through firewalls and Web proxies that might block PPTP and L2TP/IPsec
traffic. SSTP provides a mechanism to encapsulate PPP traffic over the Secure Sockets Layer (SSL)
channel of the HTTPS protocol. The use of PPP allows support for strong authentication methods,
such as EAP-TLS. SSL provides transport-level security with enhanced key negotiation, encryption, and
integrity checking. Although it is closely related to SSL, a direct comparison can not be made between
SSL and SSTP as SSTP is only a tunneling protocol unlike SSL. Many reasons exist for choosing SSL and
not IPSec as the basis for SSTP. IPSec is directed at supporting site- to-site VPN connectivity and thus
SSL was a better base for SSTP development, as it supports roaming.
http://technet.microsoft.com/en-us/library/dd469817(v=ws.10).aspx