Moreover, a well-traveled VPN carries a considerable daily administrative burden that involves moving, adding, and changing users and creates the need for subadministrators in personnel, accounting, facilities, and IS departments. It takes special skills to meet the problems of security and reliability in Internet connections. We think that managing your own busy corporate VPN with a few hundred users can occupy one skilled person full time and require the assistance of other administrators. A large part of a VPN's complexity involves security. The tunneling method between end points is separate from but closely linked to security.
Tunneling protocols encapsulate data to handle addressing and improve the chances of delivery.
L2TP encapsulates AppleTalk, IP, and IPX packets. The products we tested use either PPTP or IPSec. Neither protocol designates a specific encryption scheme, but Microsoft includes RC-4 encryption in Windows NT, conforming to U.S. export laws. And more powerful 128-bit encryption is available for download in North America. IPSec isn't mature, but it's getting plenty of growth hormones.