3 Replies Latest reply: Jan 4, 2011 8:56 AM by marc.garcia
fredz85 Level 1 Level 1 (0 points)
Is there a reason why a PPTP VPN is so slow on an iPad or iPhone (4)? When using the Speed Test app, I only get 2 to 3 Mbps (maximum), while the same VPN, using the same connection and wifi (on a Mac or a PC) gives me 16 to 20 Mbps. My VPN is not using encryption, so that can't be the problem. Is iOS to "weak" to have faster speeds than this using a VPN? When I don't us the VPN on the iPad/iPhone 4, Speed Test reports 18 Mbps, so my connection surely isn't the problem. Have other users experienced this? What are your speeds on PPTP VPN networks?

iPad
  • Smith Comma John Level 1 Level 1 (0 points)
    I'm new to VPNs, but I've read that Some protocols use two layers of TCP protocols to tunnel the data through, causing 2 layers of redundancy. It's supposed to be better to use UDP protocols, where no quality checks are informed. hopefully this helps point you in the right direction.
  • Asatoran Level 4 Level 4 (2,535 points)
    I'm using PPtP and my tests have similar speeds. In fact, the VPN connection is slightly faster than the non VPN. (1.57M down/321k up on VPN versus 1.24M down/298 up on non-VPN.)

    Many VPNs have set by default to send all traffic over the VPN tunnel. In my case, the figures could be the result of my remote being a DSL and the VPN being on cable modem. (Cable modem speeds in my area are much faster than most "basic" DSL connections.) That feature is usually desired for security purposes, but if you don't need it, then see if you can disable it.

    And you mention that you don't have encryption enabled. Which VPN endpoint are you using? Most have encryption enabled by default and some don't have the option of disabling it. (BTW, my PPtP endpoint is on a Cisco Linksys RV042 over cable modem. My iPad is connecting to a Dlink BWLG730 802.11g access point through a Cisco PIX 501 firewall over DSL. The RV042 doesn't give me the option to disable PPtP encryption, as far as I can tell.)

    (edit: BTW, the A4 CPU in the iPad & iPhone4 is basically an ARM CPU that does have much less horsepower than current model Core2 or Corei CPU. The additional overhead may be too much for the A4. But if my results are any indication, then it might not be the VPN and just a limit of the networking stack in the iOS devices.)
  • marc.garcia Level 1 Level 1 (5 points)
    Asatoran,

    would you mind sharing your PPTP VPN configuration with me? I've set up a IPSec VPN and I can successfully access my resorces using the vpn client from Shrew. I've tried a couple of times to configure a PPTP VPN in order to connect to my LAN using my iPhone 4 with no success.

    I changed my Netgear VPN Firewall because it didn't enable iPhone VPN access and bought a Cisco endpoint only to find out that it only works with a bunch of Cisco devices... how annoying.

    I would be grateful if you could help me.

    Thanks a lot in advance,

    Marc