Be Excellent To Each Other

I wanted to put friend in the heading but it wouldn't fit... anyway...

Me and a friend both have Xbox live on Virgin Media's 10meg line. We can play online against other people fine with no problems. We can even join a party or a game hosted by another friend... BUT...

We can't play or party directly against each other!

This means that if I start a party, all my other friends can join apart from this one and vice versa. It's very weird. Xbox just comes up saying "Could not connect. There could be network problems"

Has anything else seen anything this absurd? It should just work shouldn't it?!? When we do play against each other it has to be on games hosted by another friend.. We're stuffed if we're the only two people playing online!

Yeah, I had it with Dave last week. Turned out to be port problems on my router.

I thought it could be this.. any idea how to fix it?

try http://www.portforward.com and find your router make in there to follow the instructions, I did that and it allowed me to connect again. Of course, it may be your mukka's connection instead.

Ah... I get ya! I have a feeling it's his then as all my ports are forwarded properly... I'll double check though! Cheers.

We had a similar thing the other week on Rock Band with Rodafowa and Mimi. I think their star signs must be incompatible or something.

Yes, it was really odd - I could join the band, he could join the band, but we couldn't BOTH join the band. I am using Virgin cable broadband and a Linksys router. It had never happened with anyone before. Does anyone know how to fix the problem?

Dimrill, had you played against 'Dave' online before?

Aye, he has, many, many times.

My routers not excellent, added to him having a new xbox different from what his router expects made it fail.

I don't know if this is still the case, but on the original xbox it was the NAT settings which caused this.

Oooooooh, MISTER Dave. Sorry, I didn't realise Dims meant you, MrDave

NAT settings? I fear I shall never understand what that means, but that's OK.

I didn't, I tried it all, and it still didn't work so I gave up and now I await the SKY router.

<sighs>

Are you on Sky Broadband? They apparently make it quite difficult for you to use anything but their own branded equipment

Not yet, no. I was trying to set it up ages back, but lost interest and gave up. It was something to do with NATS and uPNP and I had to "forward some ports" but it wasn't easy for me to do so I gave up and joined a band instead. After we sold 5 million copies of our first single, the adulation and the excesses just got too much for me, so I spent all the money on education, and now ride my bike in the sunshine. But I still think of the sight, for those five glorious moments, of BeeXing it up on GTA IV with a helicopter, and the fun we had. Those days I miss.

Yes, this is usually the culprit.

Set the Gnats free.

Is NAT settings anything to do with port forwarding then?

I've heard of NAT settings and I'm sure I'm seen an option in my routers menu but I'm clueless as to what it does.

NAT is what makes your internal addressing (192.168.X.X) addressable by machines on the internet. It's usually not relevant to port forwarding, because if you set up port forwarding you usually specify that communication on a particular port be forwarded to a particular local IP on your network. Which is a form of static NAT, I guess.

This kind of explains the problem and may help solve it:

http://www.noddegamra.co.uk/problems-wi ... ettings/3/

NAT enables multiple computers to share one connection. It works on outgoing connections - your computer asks the internet for Beex, the router quietly replaces the computer's address with the internet address. Beex comes into the router, and the router passes it back. That's all dandy for TCP connections.

When a scary computer on the scary internet tries to initiate a connection instead of just responding, the router doesn't know what to do with it. How can it guess which device on the local side to pass it to? So it doesn't.

The same thing is true for UDP connections, which don't have state - computer sends a packet out, the router does its Network Address Translation and passes it on... and that's it. When a response comes in, it doesn't know what to do with it.

That's where port forwarding comes in - you tell the router that ah, if scary computer tries to open a connection to a web server, it should forward that to your PC under the stairs. That will work for both types of connection.

There are ways and means to guess in some cases, but things like having multiple Xboxes sending the same sort of data to the same place gets nightmarish.

UPnP is supposed to help fix this by allowing computers (and xboxes) to dynamically configure port forwarding rules on the router - the first Xbox gets the default ports (because they're spare), then the second hits a conflict and starts trying other numbers until a full set is there.

It's certainly got my Xbox, multiple Live Messengers (even two on the same laptop, with Fast User Switching) and BitTorrent clients working.

I fixed the problem! We both forward ports using our router but noticed on this site...

http://www.xboxlivetheguide.co.uk/XBoxLiveTheGuide3.php?title=My%20NAT%20Setting%20is%20Strict/Moderate%20what%20can%20I%20do

That port forwarding doesn't work when UPnP is turned on, so we turned this off and now we can party! Excellent.. I think...

Does turning UPnP off cause any problems anywhere? Everything seems to be working but I would hate to leave my router wide open for attack or something.

Isn't UPnP very much optional anyway? I think you'll be fine without it. [citation needed from someone geekier]

uPnP is basically saying "I don't want to bother working out how port forwarding works, try and sort it out for me" - so you shouldn't really have trouble with anything else.

I'd never considered UDP as being "stateless" before, that's an interesting way of defining how it differs from TCP.

It's pretty much the definition of how it differs.

I'd never considered the flow control of TCP as being state before, really. For whatever reason it wasn't defined to me that way.

Was it defined as stllllgchchchggte?

Hah! You English crack me up. It's cwmrhyllgogochgochllllwyl.