VPN Client vs VPN Concentrator 3005 using GPRS Internet Dial-up Connection

[ovieira]

Hi!

I'm having some trouble using a GPRS Internet Connection. I installed a VPN Client to connect to our VPN 3005 and it works fine but only using a regular V.90 Internet Dial-up connection. When i use GPRS i have Internet access, my VPN Client connects to the VPN3005 successfuly but i don't get any access to the remote LAN (not even the ping test!). Can the overhead of 3DES have anything to do with this subject?

Regards,

Olindo

[bwalchez]

I've never attempted IPsec 3des accross GTP/GPRS but I would think that you are running into a packet header issue. By the time the packet is encapsulated for IPSEC it's pretty large, let alone encapsulating that for the tunnel. You'll probably need some expert advice or troublshooting on this one. Come back and let me know what you learn. Anyone else out therehave any thoughts?

[benjamin]

HI!

Could be the GPRS network not allowing certain traffic. I know for a fact that 02 in the UK only allows popular apps such as http, smtp etc. Therfore you non VPN traffic possible. Vodafone and Orange in the UK are fine with VPN over GPRS whether it be Cisco, Checkpoint or whatever. I have personnaly tested all three. Ask your GPRS provider if the GPRS service is a true "open all ports" service.

[ovieira]

Hi!

I solved this problem. The GPRS provider was giving us private IPs and i had to activate "Transparent Tunneling".

Thanks for your answer.

[chphua · Accepted solution]

I have also enabled the udp encapsulation mode, however i notice that the sucess rate for the full vpn IKE establishment (complete exchange of Keys and connection) is only abt 50% of the no. of trys . Wonder if you have such experience.... Not sure is it because of the latency in GPRS.

[ovieira]

Hi!

I'm not having any problems regarding that subject. Probabily you are having some problems with your GPRS provider network. Did you question them about it?

Olindo