Microsoft Windows [Version 6.0.6001] (C) Copyright 2006 Microsoft Corp. c:\windows>netsh ras delete authtype ?
delete authtype [type = ] PAP|MD5CHAP|MSCHAP|MSCHAPv2|EAP
Deletes an authentication type from the list of types that the
Remote Access server will negotiate.
type - the type
PAP - Password Authentication Protocol (clear text).
MD5CHAP - Challenge Handshake Authentication Protocol using
Message Digest 5 hashing scheme to encrypt the response.
MSCHAP - Microsoft Challenge-Handshake Authentication Protocol.
MSCHAPv2 - Version 2 of MSCHAP.
EAP - Extensible Authentication Protocol.