VPN over Cell Network

[shadragon]

Good Afternoon,

I have an HTC Incredible S running 2.3.3 Android and HTC Sense 2.1 with Exchange Sync for my work emails. I am the system admin.

I have a wireless router both at work (on the trusted side of the firewall) and at home. When at work I can access the email server over wireless no problem (No VPN) and send/get mail fine. At home, I need to login to the VPN using wireless and once that link is up I can access my work emails fine.

However, if I am not on wireless, the VPN disconnects and when only on the cell network I cannot send/receive work email. So I have to keep signing into the VPN 8-9 times a day when I wander away from a wireless connection.

I tested the work firewall settings using the Microsoft Remote Connectivity Analyzer with my home PC and it passes. I can use OWA successfully. When I run the Exchange Sync setup on my phone at home with wireless turned off I do not see any activity on the firewall logs. Nothing denied or accepted, no traffic at all. I have to turn on the VPN before the Exchange Sync wizard will connect.

So couple of questions.

1) Can the VPN work over the cell network?

2) Shouldn't the Exchange Sync work without a VPN?

Thanks.

Shad

 

[zflamewing]

If you're not seeing your attempts on the firewall logs it sounds like your traffic is not making it to the firewall. Have you checked the other devices between the firewall and the edge of the companies network? If nothing on your companies network would be blocking that traffic then there's probably something outside The only thing I can think of keeping VPN over a cell network from working is if the provider has filters/rules in place to block that type of traffic. Does the desktop you were testing with at home have a vpn client that might have been running? I not able to provide a lot of insight on this but I hope this gives you somethings to consider on the road to your answer.

 

[vobguy]

Just to answer the question 1, yes it is possible to connect to a VPN over a cell network, I have done it with my Epic. I even established a VNC desktop session over the secure VPN connection - it was small but I could actually fix an issue that saved me two hours so it was worth it.

As far as your OWA, it should work. I use it myself without the VPN. I get email almost 24/7 from work. The only time I have problems is when I change my password and forget to change it on my phone.

However since (or if) yours works when VPN is active and doesn't when VPN is off, then you might examine the mail connection settings, especially the port settings and/or "use secure connection" checkboxes. Can't hurt, anyhow.

 

[shadragon]

UPDATE: I have been doing a lot of research on this issue and come up with some interesting info. My cell provider is filtering the GRE protocol and that is why I am unable to see any VPN traffic logged on my firewall. In order to have VPN work, I have to ask for them to move my IP to an unrestricted / unfiltered one so that all traffic to/from my phone can get through.

This is more common than I first thought and I found this article that assists in troubleshooting VPN connections.

An excellent chat thread on the topic can be found here.

Will let you know if this transition to an unrestricted IP does any good. I am yet to find someone who understands the technical aspects of this issue at my provider. I cannot get past the sales and marketing types who just keep apologizing for any inconvenience and trying to up-size my cell plan. ~sigh~

 

[Perrin]

I know it doesn't help your situation out much, but our company is actually rolling out a bunch of tablets and we needed some way to have them mobile and still connect back to our private servers. One of the carriers we are looking into has a solution to where they actually set a site-to-site vpn tunnel, so no vpn client needed, and tag traffic from the devices we tell them to go through that tunnel back to our secure network. Basically, configure the vpn on their router, tell us there configuration, and we match it on ours. That way any traffic going out the cell signal will be routed back to our network. Since these will all be company owned tablets that is great, but could cause a problem if they were personal as they will all go through our filtered firewall now as well.

Like I said, doesn't really help your situation out much, but you might try to get into contact with your provider's tech support (or demand to speak with a supervisor and then get tech support) to see if they have a similar solution. Their business accounts department might also be helpful.

 

[mrspeedmaster]

vpn tunnels work over 3G/4G . I have deployed over 400 ipads for a company and they connect through 3G. I have my touchpad rooted w/ openVPN and ICS working 70% of the time.

I connect to vpn using my mifi through both Verizon and AT&T.

You need to check the firewall logs as mentioned earlier. Also some devices only support certain VPN types. I can't get my Galaxy Nexus to work on my client's CISCO vpns but I can connect to my house because I use a low-grade L2TP.

Cisco now has Anyconnect which uses SSL 443 ports. This is the future because of the ease-of-use to configure. Anyconnect works great in coffee shop and hotels.