Motorola MG7540 User Manual page 54

 Site-to-Site VPN via IPsec (the MG7540 can be configured to create a tunnel
for all devices on the MG7540's LAN side to connect to a corporate
network).
 The MG7540 will NOT support termination of client VPN connections via
IPsec.
A couple of notes about VPN options. IPsec uses encryption and provides the
strongest security. PPTP is considered to be the least secure VPN option. PPTP
connections are not required to include encryption or authentication. L2TP is
based on PPTP, and adds some level of compulsory authentication.
In the implementation of PPTP and L2TP on the MG7540, MPPE encryption is
optional. Both protocols require a login; L2TP requires a passkey for
authentication.