Hey guys, This is a BIG deal. This advisory is explicit regarding only tunnel mode being exploited. Since L2TP/IPSec uses IPSec *transport mode* in the L2TP tunnel, its time for you to get that Cisco gear on eBay and ramp up your ISA firewalls as VPN servers and gateways NISCC Vulnerability Advisory IPSEC - 004033: http://www.niscc.gov.uk/niscc/docs/al-20050509-00386.html?lang=en HTH, Tom www.isaserver.org/shinder Tom and Deb Shinder's Configuring ISA Server 2004 http://tinyurl.com/3xqb7 MVP -- ISA Firewalls