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IPX over a single LAN?

PostPosted: Mon Aug 28, 2006 11:34 am
by daveybops
I have been searching for a program that can allow me to play IPX games over a simple home network without having to replace my switch (which doesn't support the IPX protocol). I thought I had found it in this program, but since it seems to be for use over the internet to create a single LAN (kinda like a VPN, but not quite), it seems to do the encapsulation fine, but won't send the packets where I want, ie internally.

The game in question is C&C Tiberian Sun.

Could this be a suggestion for the future development of GIT, or is it already possible with the correct settings?

PostPosted: Mon Aug 28, 2006 1:14 pm
by Ark
Switches typically segregate traffic on the data link layer, not the application layer. Also, given the similarities between the 802.3 data link level header typically used with IPX (directly, or via 802.2 or via SNAP) and the Ethernet II (DIX) data link level header typically used with IPv4 - nearly all switches simply look at the 6 byte machine address destination to route traffic to the correct hardware port on the switch.

The problem may lie in not having the IPX protocol installed on each machine trying to run the game, or in the IPX protocol being transmitted with different frame types. It is most advised to manually configure each machine to use 802.2 frames for IPX, but if this does not work because your switch really is odd and not sending those packets on, you could always try Ethernet II on each machine, which is the exact frame type IPv4 is always sent out on.

If your switch is still seriously blocking IPX traffic because it is looking at the network level headers and acting as a firewall as well, and you have no way to enable it to act like you want and send the IPX traffic across your network, and you can't return the switch for something that works like it should, then it should still be possible to use GIT to tunnel the IPX. As far as GIT is concerned, your switch separates two LANs, it doesn't matter if it is across the Internet or not. Just configure GIT to forward IPX, make sure the proper frame types are being looked at by GIT, and that you are forwarding the correct IPX socket numbers for the game you are using.

PostPosted: Mon Aug 28, 2006 2:27 pm
by daveybops
Thanks, I'll try changing the frame format.

A traditional switch doesn't seperate LANs, it seperates collision domains within the LAN. It's been a year since I read that stuff for my course, but it uses MAC addresses instead of IP addresses, so I can't figure out why it won't work. However, mine is an ADSL router with built in switch, so if the switch actually looks at the network address (unlike trad switches that look at the MAC address), then I'm screwed.

So because I have one LAN seperated into multiple collision domains and the switch is being an a*se and ignoring IPX packets, then GIT won't work because it uses seperate LANs.

But maybe it is just the frame format that needs fixing.

Fact is, I don't know enough about IPX and I don't know enough about any router not made by Cisco, and I need to do some revision anyway, because my CCNA3 is starting in a couple of weeks and all my knowledge has leaked out through my ears while sleeping.

PostPosted: Mon Aug 28, 2006 3:39 pm
by Ark
I'm saying that if IPX packets can't traverse your switch, than as far as IPX is concerned, you have two (or more) separate LANs (well, each LAN contains its own single computer at that point as well). As far as IPv4 is concerned, you have 1 single LAN.

You can easily run GIT on 1 computer per LAN (thus, GIT on every single computer you want to play the game on, unless you happen to have a hub behind the switch and more than 1 computer per switch port). As long as GIT can communicate to other GITs via UDP or TCP, it can easily tunnel your IPX traffic.