Understanding network bridging in Windows XP

Have a wired network, Network A, using 10.x.y.z range, with a gateway to the
Internet.

Also have a totally separate wireless network, Network B, using 172.1.a.b
range

Have a notebook running WinXP Pro with 2 network interfaces, one for the
wired network,
the other wireless. I bridge the 2 interfaces.

From a PC on Network A, I cannot ping a computer on Network B (possibly due
to the gateway).
The PC on Network B has its firewall disabled, of course.

Before I go and make IP configuration changes (and re-set up my little
experimental network again),
is it possible for a host on either network to communicate with a 2nd host
on the other network
using the Bridge? (Yes, I know I can get it to work by setting up my
notebook as a router
and adding static routes if necessary).

Or is Bridging only meant for separate networks that use the same IP (but
non-overlapping) range?

wifi

In article <#>, "wifi"
<root@[127.0.0.1]> wrote:
>Have a wired network, Network A, using 10.x.y.z range, with a gateway to the
>Internet.
>
>Also have a totally separate wireless network, Network B, using 172.1.a.b
>range
>
>Have a notebook running WinXP Pro with 2 network interfaces, one for the
>wired network,
>the other wireless. I bridge the 2 interfaces.
>
>From a PC on Network A, I cannot ping a computer on Network B (possibly due
>to the gateway).
>The PC on Network B has its firewall disabled, of course.
>
>Before I go and make IP configuration changes (and re-set up my little
>experimental network again),
>is it possible for a host on either network to communicate with a 2nd host
>on the other network
>using the Bridge? (Yes, I know I can get it to work by setting up my
>notebook as a router
>and adding static routes if necessary).
>
>Or is Bridging only meant for separate networks that use the same IP (but
>non-overlapping) range?

Think of the network bridge as a virtual hub, and think of the bridged
network connections as ports on a virtual hub. Like a physical hub,
the network bridge has no routing capability. It simply repeats
incoming packets from each port on all of the other ports.

The network bridge was designed to combine two or more physically
separate networks into one virtual network with one IP subnet, one
DHCP server, etc.

By the way, 172.1.a.b is a public IP range. The private IP range is
172.16.0.0 - 172.31.255.255. Details here:

Address Allocation for Private Internets
http://www.ietf.org/rfc/rfc1918.txt

I hope that you're enjoying your experiments!
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

Steve Winograd [MVP]

"Steve Winograd [MVP]" <> wrote in message
news:...
> In article <#>, "wifi"
> <root@[127.0.0.1]> wrote:
> >Have a wired network, Network A, using 10.x.y.z range, with a gateway to
the
> >Internet.
> >
> >Also have a totally separate wireless network, Network B, using 172.1.a.b
> >range
> >
> >Have a notebook running WinXP Pro with 2 network interfaces, one for the
> >wired network,
> >the other wireless. I bridge the 2 interfaces.
> >
> >From a PC on Network A, I cannot ping a computer on Network B (possibly
due
> >to the gateway).
> >The PC on Network B has its firewall disabled, of course.
> >
> >Before I go and make IP configuration changes (and re-set up my little
> >experimental network again),
> >is it possible for a host on either network to communicate with a 2nd
host
> >on the other network
> >using the Bridge? (Yes, I know I can get it to work by setting up my
> >notebook as a router
> >and adding static routes if necessary).
> >
> >Or is Bridging only meant for separate networks that use the same IP (but
> >non-overlapping) range?
>
> Think of the network bridge as a virtual hub, and think of the bridged
> network connections as ports on a virtual hub. Like a physical hub,
> the network bridge has no routing capability. It simply repeats
> incoming packets from each port on all of the other ports.
>
> The network bridge was designed to combine two or more physically
> separate networks into one virtual network with one IP subnet, one
> DHCP server, etc.
>
> By the way, 172.1.a.b is a public IP range. The private IP range is
> 172.16.0.0 - 172.31.255.255. Details here:
>
> Address Allocation for Private Internets
> http://www.ietf.org/rfc/rfc1918.txt
>
> I hope that you're enjoying your experiments!
> --
> Best Wishes,
> Steve Winograd, MS-MVP (Windows Networking)
>
> Please post any reply as a follow-up message in the news group
> for everyone to see. I'm sorry, but I don't answer questions
> addressed directly to me in E-mail or news groups.
>
> Microsoft Most Valuable Professional Program
> http://mvp.support.microsoft.com

Thanks for the heads up Steve.
Much appreciated.

wifi