I am running an openvpn server with open key infrastructure at home that I connect to whenever I'm away. I am at the moment running this via the official openvpn client app, but found that there is a vpn setting in the system settings. Are there any advantages with one over the other, or could I just get rid of the extra app and go with the "native" option?
I am using cyanogenmod 10.1.3-RC2-I9300 4.2.2 on a Samsung Galaxy S3
I used to use PPTP, but switched to OpenVPN, which is now what I prefer.
As far as security, OpenVPN is known to be pretty bulletproof. PPTP is the only one with real issues, though it's still fine for protecting against your average dope using Firesheep at Starbucks.
Given the recent NSA revelations I personally wouldn't touch the ones by Cisco and/or Microsoft (PPTP, L2TP) with a 10 foot pole. The other ones supported by Android were designed in the open by committee (the IETF), which I know nothing about other than we now know the NSA tried to influence that kind of thing. But I think it's unlikely they seriously broke them if they tried so whether that bothers you depends on your level of paranoia about the NSA.
As far as the UI goes, the built in VPN configuration UI is a little clunky, and OpenVPN's is a little more clunky. But when you want to connect to the VPN, you have to go through a few layers of settings to get to the built in stuff, whereas you can have the OpenVPN icon right on your homescreen.
The built in VPN doesn't attempt to reconnect if you get disconnected. OpenVPN can be configured to retry a certain number of times. This was big for me.
You can't use the native option for OpenVPN as it's not compatible with IPSec, IKE, PPTP, or L2TP, which are the only types of VPNs supported by Android:
http://openvpn.net/index.php/open-source/341-openvpn-compatibility.html
All VPN protocols (PPTP L2TP, OpenVPN) have distinct advantages and disadvantages.
Here are some points that might be useful to consider:
OpenVPN is the protocols least likely to be blocked by servers or firewalls and generally thought to be the most secure. It's because both PPTP & L2TP uses fixed ports, if your service provider or firewall blocks certain communication ports used by PPTP or L2TP, they won’t work while openVPN can be configured to use any port (on the server side) and supports multiple protocols.
Most operating systems and devices have built-in support for PPTP and you simply need to fill in a server address, a username and password to configure and no additional software is needed while OpenVPN requires installing additional software. On some devices it can be complicated. Sometimes a user is required to deal with certificates, configuration files, etc.
In terms of speed, generally speaking, less encryption means greater speed but at the cost of less security. However, if your devices are of reasonable speed this should not be a major factor. Some people say openVPN on UDP is the fastest but according to my own experience on pureVPN, they are all more or less the same. Speed depends much more on your connection to the server and other factors.
In a nutshell, it's best to consider your security requirements and pick a protocol accordingly.
