Which Restriction Prevents a Designer from Using a GDOI-Based VPN

Multiple Choice

Which restriction prevents a designer from using a GDOI-based VPN to secure traffic that traverses the Internet?

A) Enterprise host IP addresses are typically not routable.
B) GDOI is less secure than traditional IPsec.
C) Network address translation functions interfere with tunnel header preservation.
D) The use of public addresses is not supported with GDOI.