Split tunneling vs. controlling through ACL on ASA

[John Blakley]

All,

Probably stupid question, but, doesn't the "Allow Local LAN Access" option under the VPN client have to work in conjunction with the policy on the ASA? Also, what is the real difference between split tunneling and me just controlling what networks are allowed over the tunnel?

Thanks,

John

[Ricardo Prado Rueda]

Hi,

   The "allow local LAN access" option is used when you want to encrypt all the traffic from the VPN Client except for the Client's local LAN access. Normally, a VPN session without Split Tunneling will encrypt all traffic from the client, isolating it from the rest of the network (you could not print locally while the VPN session is established). This option will let the VPN Client know that it needs to allocate a static route for its directly connected network in order to avoid this situation, everything else will get encrypted, so this option is independent from the Split tunneling option. Regarding your second question, the most important difference I can think about is that with split-tunneling the VPN Client knows which networks require encryption, thus you are not consuming local resources (CPU utilization for encryption/decryption on both the client and the VPN server and bandwidth on both ends) for traffic that would eventually just be dropped (filtered) by the ASA if you just filter the networks on the ASA.

   Regards,

Rick.