... (PPTP) or Layer 2 Tunneling Protocol (L2TP). PPTP: Point-to-Point Tunneling ProtocolPPTP is an industry standard tunneling protocol. It was in Windows NT4.0 and is also supported in Windows 20 00. ... instance, FTP). Windows 20 00 includes NAT editorsalready built-in for FTP, ICMP, and PPTP. Windows 20 00 doesn’tinclude editors to translate SNMP, LDAP, Microsoft COM, or RPC.91_tcpip_09.qx 2/ 25/00 ... 11:15 AM Page 5155 02 Chapter 9 • Troubleshooting Remote Access in a Windows 20 00 TCP/IP NetworkTroubleshooting VPN Connectivity ProblemsVirtual Private Networking (VPN) is a popular solution for...