Why do I need a network bridge anyway

Discussion in 'Windows Desktop Systems' started by borked, Jun 29, 2002.

  1. borked

    borked Guest

    Ok let me start with a little background information. I have a small home network that includes 4 computers, and they all share a cable connection. The 4 computers are a Mac G4, a mac ibook on airport, and two AMD 1.7 machines running windows XP. Here is how my network is set up physically:

    NAT Router connects to Mac G4 and a hub up in the attic. The G4 "bridges" the ibook with the router for internet on the ibook, although macs don't have "network bridging" like windows xp. Its some kind of automatically configured port forwarding; I dont know exactly how it works because the computers set it up for me. The two XP machines plug into the hub in the attic, which you will recall is plugged into the NAT router.

    This seems to me like a direct connection from each of my XP computers to my router. Accordingly, the correct setup in the Windows XP Network Setup Wizard (e.g. the one that works), is "This Computer Connects To The Internet Through Another Computer On My Network Or Through A Residential Gateway". When I run it with that option, it sets up a bridge. *WHY* does it set up a bridge? I can unbridge all the network adaptors that are not the ones I use to connect to the hub in the attic (I don't use them at all) and I still have internet. But if I unbridge the card that connects to the hub, I loose internet.

    Here's my second question: Why do I need to have this card bridged? . After all, the whole point of a bridge is to bridge TWO OR MORE adaptors together. For instance, you have 3 computers, A, B, and C. A connects to B, and C connects to B, but A doesn't connect to C. So what do you do? You bridge the adaptors that connect to A and C on computer B and then A and C are connected. Right?

    So having ONE adaptor on a bridge serves no point. And bridges aren't a tool that should be used the way my network is set up. But in this case it is vital. I have a feeling that figuring this out will be a key to unraveling the mystery of my network, which is bothering me. Any illumination is helpful!
  2. borked

    borked Guest

    btw I made sure that the TCP/IP configuration is the same for the card when it isnt bridged as the bridge's TCP/IP configuration.
  3. Zedric

    Zedric NTFS Guru Folding Team

    If you don't use all your NIC:s pull them out. Easier with just one. Just set the NIC to automatic IP (if router is running a DHCP server) and you're off. It really should work. Run ipconfig to see if you get an IP. No need for bridging. Why XP wants to bridge, only Bill knows... ;)
  4. jcoria

    jcoria Guest

    do u have a firewire

    i had the same thing happen to me and i figured out it was confuguring my firewire port as a network adapter. look in device manager under you network adapters and if it says 1394, then it is the culprit of the bridging in case you want to share using it...just disable it

  5. borked

    borked Guest

    ya I know, 2 of the "network adaptors" are firewire ports...but the problem is that I don't know why XP wants to bridge my ONE NIC that is connected to the router. It won't work without the bridge so something is screwy... Zedric .. I know, I've done that, it just aint working. Its really weird.