Simultaneous PPTP OpenVPN

[Mike4560]

I'm trying to use an OpenVPN client and a PPTP server on one router, but I cannot connect to the PPTP server when the OpenVPN client is running. I can connect to the PPTP server and NAS storage when the OpenVPN client is off. I would like to have the OpenVPN client on 24/7 with a NAS storage device connected to the router accessible to PPTP clients simultaneously. I would like to eventually switch to using an OpenVPN server for the NAS. Would that work better anyway? thanks.

 

[bill001g]

To a point you have to be happy that your router even supports both protocols. It tends to be a little tricky to get multiple vpn services running even a linux based server. Mostly it is a routing thing but it can be done....the router manufacture may just have decided not to support both.

PPTP is based on gre protocol which works similar to UDP in that it does not do any data correction or recovery at the packet/segment level. Openvpn uses by default TCP similar to HTTPS to communicate. The disadvantage is your transfer rates can be limited by the tcp windowing and if you get errors the recovery in the tcp can cause added jitter to the enclosed data.

The main advantage is since it mostly appears as https it will easily pass though nat and firewall without special options or configurations. You can change openvpn to use UDP rather than TCP to get rid of the TCP penalty. It still passes though NAT a bit easier but it now a non standard thing that many firewalls will block. UDP is used to attack things so many firewall block it by default.

The other major difference is openvpn encryption is much more processor intensive than most other forms of encryption. PPTP does not even have to be encrypted if you choose

 

[Mike4560]

Thank you.