O2 Hotspot VPN access

iwb

I hope someone has already figured this one out. I hate it when i'm the first:D
I was at the Burlington this evening trying to establish a VPN over their O2 wireless network. I thought I was in luck, as it did everything it normally does on my home DSL (Eircom solo). It seemed to establish the connection and I assumed I was ready to go but I tried to open my email (exchange on Outlook) to no avail. I then tried to ping internal addresses and nothing either.
I then discovered that I couldn't do ordinary browsing until I killed the VPN. Browsing worked fine after that.
I had tried this previously at the Alexander using Eircoms service and got the same results, exactly. I would love to be able to VPN from these locations as it would save me a bunch on phonecalls. I can use a softphone if I can tunnel.
If anyone has any experience I would appreciate it.
Also, the connection seemed fairly flaky with wildly varying ping times and one online speed test gave me a result after repeated trys of between 65 and 88 kbps. Little better than dialup!

Mutant_Fruit

i'm not sure if this is relevant, but running a VPN inside a VPN is only supported by Win 2000/XP. That could be why you can't connect. Most wireless networks are a VPN, so either get windows 2000/XP or give up.

If you have win 2000/XP, then i don't know why you can't.

EDIT: after further thinking i'm about 75% certain this is you're problem

crowbar

it's definitely not a vpn within a vpn. how do you come to that conclusion?

you can try reducing the mtu on your wlan adapter, that tends to get vpns working over dsl though i didn't have to do that with the wireless lan. i've used checkpoint fw-1 ng and cisco's vpn client over the o2 network and they both worked for me. iwb, which client are you using (if you are allowed to say)?

with some vpn clients, when you connect to a vpn, everything gets sent down through the vpn so the rest of the internet is only accessible if the vpn/firewall at the other end allows it. the most noticeable effect of this is the window with your online time stops working, though if you disconnect your vpn and refresh that window then it usually comes back.

iwb

Thanks for the speedy replies guys. I am using the Cisco VPN Client. I will try to reduce the mtu figure on the adaptor.
For the record, I am using XP and my laptop works just fine on my home DSL connection but not on O2, so I am assuming it is just the connection, not an issue with all traffic going over the VPN.
I am going in there again today so I will screw around with it.
Someone told me that if O2 is using port address translation I won't be able to do it at all. NAT will be fine though. I have no way of knowing until tomorrow, if they will tell me at all, as they are on holiday.
Thanks again for the help.

crowbar

t-mobile's network in the us definitely does pat/nat as i got a 10.x.x.x address when attaching - consequently i couldn't get my vpn client to work on it at all as we use 10.x.x.x too and the vpn client thought i was already inside my network so did nothing. the o2 wlan network does not nat or pat as you get a public ip address when you attach so there's really no need to.

iwb

OK, my IP address here is 62.40.47.27. Is this a routable, public IP address?

crowbar

yep, that's public all right. any luck with the vpn client?

iwb

Got it yesterday. I played around with it and in truth, I cannot say exactly what I did. One thing that seemed to interfere was the XP firewall. When I took that down, I got further.