[funkboy]

iChat and MSN keep losing connection every ten minutes (or less) with AirPort. The same card has produced this effect on both an iMac and an iBook (both new, white models) and in two separate physical locations hundreds of miles apart with two separate Airport Base Stations (both grey original ones). The AirPort card itself is an original card, too.

Any idea how to stop them from losing connection? Everything else downloads and works just fine, but messaging tools lose their connection with it. Could it be a faulty card? That's my only idea, but I'm hoping for a software/settings solution... that's preferably free

[funkboy]

Nobody has any idea for a fix at all?

[ghporter]

What are you doing (other than chatting) when you lose your connection? Are you at some certain distance when this happens?

Also, I've heard that MSN doesn't like some implementations of Network Address Translation. It's possible that this is the case.

Have you checked Apple's KnowledgeBase for this situation?

[funkboy]

Originally posted by GHPorter:
What are you doing (other than chatting) when you lose your connection? Are you at some certain distance when this happens?

Also, I've heard that MSN doesn't like some implementations of Network Address Translation. It's possible that this is the case.

Have you checked Apple's KnowledgeBase for this situation?

No certain distance, I'm getting four bars with Airport. The connection itself doesn't time out, only the iChat/MSN connection.

I've checked Apple's KB, but have turned up nothing.

Where would I check out Network Address Translation? Or fix it somehow?

I think it may be a problem with my whole network, now... the computer downstairs on wired ethernet usually didn't have that problem, but now it seems to be suffering it, as well.

So, how about just generally dropping iChat and MSN connections overall, on wired or wireless networks? How could I fix that?

[ghporter]

The "problem" is that your wireless network's NAT is doing its job just fine. There is no "fix," as such, just some work arounds. The first thing to look at is how much you depend on iChat and MSN. If you can't do without them, then you may have to look at purchasing a gateway router to put between your broadband connection and (I'm guessing here) your AirPort Base Station. (If you're already using a wireless router instead of an ABS, you'll figure out where I'm going pretty soon...)

Here's how NAT works. Your LAN computer issues a request for something on the Internet. The NAT section of the router (this includes an ABS) takes that request and alters the port portion of the packets to indicate (internally) which LAN address the request came from. When a reply comes in, it's aimed at the (WAN) IP address and port that requested it, so the NAT system "unalters" that port information to make it go to the real port from the correct LAN address. This process is how your ABS, gateway router, etc. allows many computers to share one Internet (or WAN) IP address. There's no guarantee that successive requests will be altered the same way, so port-sensitive connections like iChat and MSN Messenger, get lost.

Most gateway routers provide the capability to establish a "DMZ," basically set out one LAN address whose connection isn't translated by NAT. Different brands do this through different configuration settings, but the result is still the same. Most also give you the ability to forward certain ports to specific LAN addresses. This limits the target computer's exposure to the bad guys, but should still allow many connections that would otherwise be blocked or interrupted.

I hope this helped.

[funkboy]

Interesting, thanks for the info.

I'm on Qwest DSL behind a Cisco 675 modem/router. I guess I never had these problems before I added on the Airport to my LAN setup, so I bet you're right.

iChat and MSN are very important to me - especially because they barely stay connected (MSN especially) for three minutes and then they disconnect.

Are you saying I'd have to put a router between my Cisco 675 modem and between my ethernet hub? It seems like I should know more about networking, but I'm a little confused right now, being on vacation and all

Thanks much!

[ghporter]

I don't know a lot about Cisco's modems, but most of them seem to be modem/routers anyway. You may be able to set up port forwarding or a DMZ with the modem itself. However, if the modem has only one port (that's connected to your AirPort Base Station), you may have to buy an inexpensive router too.

You should also note that Microsoft has just released an update for the WindowsXP MSN Messenger client to address NAT problems-a Mac client update may be coming. Amazingly, somebody (MS of all companies!) has realized that a lot of customers like the security and flexibility of using NAT routers, and don't like having software break because the programmers didn't think about NAT in the first place.

[funkboy]

Originally posted by GHPorter:
I don't know a lot about Cisco's modems, but most of them seem to be modem/routers anyway. You may be able to set up port forwarding or a DMZ with the modem itself. However, if the modem has only one port (that's connected to your AirPort Base Station), you may have to buy an inexpensive router too.

The Cisco modem goes from the wall to the uplink port on my Ethernet hub. The Airport and my beige G3 are plugged into the hub as well, in regular ports.
I telnetted into my Cisco last night and set up a nat forward for the MSN port to go directly to this local ip, but it still isn't working. I also turned up the udp and icmp (I think that last one was the acronym) timeout to 3600 seconds. However, neither of these things helped.

You should also note that Microsoft has just released an update for the WindowsXP MSN Messenger client to address NAT problems-a Mac client update may be coming. Amazingly, somebody (MS of all companies!) has realized that a lot of customers like the security and flexibility of using NAT routers, and don't like having software break because the programmers didn't think about NAT in the first place.

I guess I'll just have to hope they release this for Mac soon, and that Apple realizes it, too. Time for some feedback to Apple.

If I get a router to go between my Cisco 675 (which I can telnet into and set up NAT tables, even though they don't seem to be properly forwarding the ports to the computer I told them to), that won't help the situation at all, will it? The Cisco should be able to do it if it's configured properly, I think. I don't know why it isn't working...

[ghporter]

Is the device you called an "ethernet hub" actually a hub or some sort of switch? If it's a switch, there may be configuration changes you'd need to make in it, as well. What's the brand and model-I'll see what I can dig up.