This article was previously published under Q249278
Windows 2000 Virtual Private Network (VPN) connectivity has been tested with Cisco Internetwork Operating System (IOS) versions 12.0.5T and 12.0.6T. This article describes the supported scenarios for compatibility between these two programs.
The following scenarios are supported using IOS versions 12.0.5T and 12.0.6T.
Windows Client to IOS Gateway VPN Tunnel
A Windows client connects to a Cisco IOS VPN Gateway using Point-to-Point Tunneling Protocol (PPTP) or Layer Two Tunneling Protocol (L2TP). Windows 2000 currently supports L2TP.
Windows Routing and Remote Access (RRAS) Gateway to IOS Gateway VPN Tunnel
A PPTP or L2TP/IPSec VPN tunnel is established between a Windows server running RRAS and a Cisco IOS router.
RRAS to IOS Gateway-to-Gateway Pure IPSec Tunnel
A tunnel is established between Windows RRAS and Cisco IOS using just IPSec in tunnel mode (L2TP is not used).
Pure IPSec tunnels are supported in Windows 2000 only for Gateway-to-Gateway configurations (not supported for Client-to-Client or Client-to-Gateway tunnels). For Client-to-Client security, IPSec can be used in Transport Mode, where the Authentication Header (AH) and/or Encapsulating Security Payload (ESP) IPSec protocols are used to protect the TCP/IP packet.
For additional information, click the article numbers below to view the articles in the Microsoft Knowledge Base:
249067 How to Configure Cisco IOS for L2TP/IPSec in Windows 2000
249125 Using Certificates for Windows 2000 - Cisco IOS VPN Interoperation