VPN support is now expanded to include IPSec based VPN with UDP transport as well as plain L2TP without IPSec. The VPN deployment must be capable of NAT traversal.
The expanded VPN support is available with the TetherBridge-Mobile v1.2.0 / TetherBridge-PC v1.1.0.0 software bundle or later.
The newer versions of Cisco VPN client are capable of automatically recognizing the local MTU and setting it for the VPN interface. If you have an older version of Cisco VPN client which is not capable of doing so, you should set the MTU to the default of 1300 using the Cisco VPN SetMTU utility.
Unlike the Cisco VPN client, a Nortel VPN deployment does not reflect or adapt to the local MTU on the client side well. The MTU is set at the VPN server side on Nortel Contivity. Contivity relies on ICMP messages to determine the path MTU from the server to the client. This methodology is not guaranteed to work as some routers on the way may be configured not to send ICMP packets. This is particularly true for some switches in the cellular networks. Nortel Contivity has a default interface MTU of 1500 which will not work with TetherBridge. With consideration of the native IP tunneling within the cellular network, TetherBridge has a MTU of 1460 to allow it to be compatible with more cellular networks. As a result, the interface MTU on Nortel Contivity should be set to no larger than 1460. You need to request your IT administrator to reconfigure it if it is not configured as such. The Nortel Contivity should also be configured with the DF (Don't Fragement) flag enabled. If you require your IT admin to make configuration changes and if you expect it to take time, we recommend you postpone your TetherBridge trial so that you would not waste your TetherBridge trial period.
The TetherBridge-Mobile v.1.2.0/TetherBridge-PC v1.1.0.0 (or later) software bundle provides expanded VPN support for corporate users who need access to coporate VPNs. IPSec based VPN with UDP transport, as well as L2TP without IPSec, is supported in addition to SSL/TLS based VPN.
This TetherBridge-Mobile v.1.2.0/TetherBridge-PC v1.1.0.0 software bundle gives you a 5-day trial period. If you have tried earlier versions of TetherBridge software before, this test software will restart the trial period and give you another 5 days to try.
Because VPN deployment can vary in many ways, you are encouraged to contact us for technical support if you run into any issue. You may also find the following notes handy.