Also, my SonicWall VPN Client software can access my network through a SonicWall XPRS2 with no errors IF the PC running the client software is cabled directly into a cable modem. If, however, a SMC Barricade ABR Router is used between the PC and the cable modem, the VPN client cannot access the network. What would cause this and how would I correct it?
I don't know AS400 terminal emulation at all (so I'm really stretching to guess here on the first question) but it's likely the control and function keys are only being echoed locally by the emulation program and are not being transmitted across the wire. There may be a setting in the emulator to ensure that these are also transmitted, not just locally echoed.
Regarding the use of the SMC Barricade: When you're directly connected to the cable modem, you're assigned a publicly routable IP address from your ISP, so your VPN works fine. However, when you go through the Barricade, it is performing Internet connection sharing (ICS), so you are being a signed a private IP address that the Barricade NATs. This will break the IPSec client connection. In order for this to work, you need a solution that supports NAT-traversal. These are available from companies including NetScreen, Cisco, Nortel and OpenReach. I don't believe SonicWall supports this with the XPRS2, but you might contact them to ask if the support NAT-traversal.
Hope this helps,
This was first published in August 2002