[dvdnet]

Folks,
I've had my netgear DSL 4 port modem and airport extreme for over a year now and I use an Asus laptop and a PB17 when i work from home. The problem is that I can no longer connect to my company office VPN via a wireless connection using the Cisco VPN software.

It has been working fine for a year then all of a sudden it just won't access the host at all. If I connect via wired to the netgear, it all works fine. Now I'm stuck in the corner of my house when I need to connect to the office as opposed to floating around wherever I please like I used to.

I can't attribute this to when i upgraded to panther or when I updated the airport extreme to 5.2.

Any recommendations, checks, tests, procedures you can recommend?

Thanks in advance,
Steve

[ghporter]

Unless you've changed the firmware or software of your AirPort Extreme base station, the problem is at the other end. It would appear that something in your company's VPN has changed, something that involves (probably) packet size or timing. I'd ask your IT people if there's been some sort of change in configuration or settings that you need to update your VPN client with, and explain exactly why.

VPNs typically use "encapsulated" data packets; packets with your private data are enclosed in standard packets for travel through the network. Your DSL system has a specific maximum packet size, based on how you connect. With a PPPoE connection, the maximum size is 1492 bytes per packet. VPNs have to fit their data and overhead into those packets, so the 'internal' packets have to be smaller. You could experiment with packet size in the Cisco client, but it would be much easier to get the 'standard' settings from your IT folks.

[dvdnet]

Originally posted by GHPorter:
Unless you've changed the firmware or software of your AirPort Extreme base station, the problem is at the other end.

Well the upgraded firmware is probably the likely culprit here. I'm speaking with the IT crew at the moment and they can't see any differences. I've spoken to others here at work with the same setup, airport, netgear DSL and PB17 and they are able to connect fine. They don't seem to have upgraded their firmware.

I think there may be an issue with NAT with the new firmware.

Is there anyway to downgrade the firmware on the airports?

Steve

[dvdnet]

Ok, i just reinstalled the 5.1.3 firmware and i can connect via VPN to the office through wireless.

I think I'm going to avoid updating the firmwares on the base station for a while, i had more problems with 5.2 than any other update, including dropped signal strength and total disconnections.

Cheers and thanks again Glenn,
Steve

[ghporter]

Glad to help. I make it a very solid rule to NEVER mess with firmware unless it fixes a real problem (not just an annoyance) that I'm really having, of provides a function I really, really NEED. So far, I haven't done much firmware upgrading, but I haven't had any snafus, either.

[dvdnet]

Originally posted by GHPorter:
Glad to help. I make it a very solid rule to NEVER mess with firmware unless it fixes a real problem (not just an annoyance) that I'm really having, of provides a function I really, really NEED. So far, I haven't done much firmware upgrading, but I haven't had any snafus, either.

Well, I spoke too soon as the issue has appeared yet again. I even went back to 5.0.1 and still an issue. Gonna take the equipment in to work on monday and get the IT crew to look into it themselves and debug.

Thanks again
Steve

[dvdnet]

Ok folks,
I stumbled across the cause of this problem a few weeks back so thought I'd mention it in here for record purposes. It seems the problem was caused by having 'Internet Connection Sharing' on. I dunno how I stumbled across it but that's what it ended up being in my situation. If I have it enabled, while I connected my other laptop to the PB17 via ether.

If it's enabled and then I try to connect via the Cisco client, it just gives me an 'ok' dialog. If I turn off the sharing and then try to connect, all works fine. I can then turn sharing back on and continue on my merry way.

Just to let you all know.

Thanks again for your responses.

Cheers,
Steve