IPSec in a Windows 2000 World

Explore the intricacies of IPSec in a Windows 2000 environment through this comprehensive Black Hat conference talk. Delve into client remote access VPN protocols, focusing on the Layer 2 Tunneling Protocol (L2TP) and its integration with IPSec. Learn about the L2TP Extensions working group, UDP usage for control and data packets, and the well-known port 1701. Discover how the L2TP/IPSec VPN Client enables migration from PPTP while maintaining functionality. Understand the automatic generation of IPSec security rules and the initiation of security when sending packets. Gain insights into the Windows 2000 L2TP/IPSec VPN Client and its automatic IPSec configuration for remote access.

Intro
Client Remote Access VPN Protocols
Layer 2 Tunneling Protocol • Designed in IETF PPP Extensions working group • Combination of Cisco LF & PPTP features, L2TP RFC
L2TP Extensions working group established Uses UDP for control and data packets, well kn port is 1701
L2TP/IPSec VPN Client • Enables migration from PPTP, same functionality, • L2TP Integrated with IPSec
L2TP/IPSec Client Automatically Generates IPSec Security Rule
Sending packets initiates security
Remote Access L2TP VPN Client - Automatic IPSec configuration
Windows 2000 L2TP/IPSec VPN Client