With both wireless & ethernet connected, which connection does Windows use?

They are giving a routing metric. The one with the lowest metric is used.

Go to the command prompt and type Route Print

See the "route print" below. It's kind of hard to understand. There are multiple "25" metrics. Which one does it use? Lan or Wan?

Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp.

C:\>route print =========================================================================== Interface List

0x1 ........................... MS TCP Loopback interface 0x2 ...00 22 14 ac 03 28 ...... Broadcom 440x 10/100 Integrated Controller

- Pac ket Scheduler Miniport

0x3 ...00 6f 16 95 bc 9e ...... Intel(R) PRO/Wireless 2200BG Network Connection

- Packet Scheduler Miniport =========================================================================== =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 192.168.1.40 192.168.1.102 25 0.0.0.0 0.0.0.0 192.168.1.40 192.168.1.101 20 192.168.1.0 255.255.255.0 192.168.1.101 192.168.1.101 20 192.168.1.0 255.255.255.0 192.168.1.102 192.168.1.102 25 192.168.1.101 255.255.255.255 127.0.0.1 127.0.0.1 20 192.168.1.102 255.255.255.255 127.0.0.1 127.0.0.1 25 192.255.255.255 255.255.255.255 192.168.1.101 192.168.1.101 20 192.255.255.255 255.255.255.255 192.168.1.102 192.168.1.102 25 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1 224.0.0.0 240.0.0.0 192.168.1.101 192.168.1.101 20 224.0.0.0 240.0.0.0 192.168.1.102 192.168.1.102 25 255.255.255.255 255.255.255.255 192.168.1.101 192.168.1.101 1 255.255.255.255 255.255.255.255 192.168.1.102 192.168.1.102 1 Default Gateway: 192.168.1.40 =========================================================================== Persistent Routes: None

There aren't any duplicated routes with the same metric here, but rather, you have two almost identical routing options for any particular destination, one with a metric of 20 and the other with a metric of 25.

The only routes that aren't exactly duplicated are the 192.168.1.101 and

192.168.1.102 routes which are routed as loopback addresses.

Since 20 wins over 25, 192.168.1.101 will be the default interface.

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D

=A0 =A0 =A0 Interface

68.1.40 =A0 =A0192.168.1.102 =A025 68.1.40 =A0 =A0192.168.1.101 =A020

=A0192.168.1.101 =A020

=A0192.168.1.102 =A025

=A0 =A0 127.0.0.1 =A0 =A020

=A0 =A0 127.0.0.1 =A0 =A025

.168.1.101 =A020

.168.1.102 =A025

.0.1 =A0 =A0 =A0 127.0.0.1 =A0 =A01

1 =A0 =A0192.168.1.101 =A020 2 =A0 =A0192.168.1.102 =A025

.168.1.101 =A01

.168.1.102 =A01

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D

You can chose which interface to use:-

The only entries that are particularly relevant are the top four.

The top two determine which interfaces are used for traffic sent to your router, the next two are for local traffic to PCs on your local network. In both cases interface 192.168.1.101 is being used since the metric is 20 which is better than 25.

Just ignore the rest, it is only there to confuse you:)

I first ran an "ipconfig /all" which defined the LAN at 192.168.1.101 and the WAN at 192.168.1.102.

Then I ran a "route /print" which reported the 192.168.1.101 metric cost was 20 and the 192.168.1.102 metric cost was 25.

So, given your information, I can conclude the WinXP PC is using the LAN which has a lower metric cost than the WAN.

Is a "20" a "decent" metric cost?

The ipconfig command doesn't tell you that. It tells you the IP address assigned to each network interface, their respective subnet masks, gateways, and DNS servers.

What you found is that one of your network interfaces is assigned the IP address 192.168.1.101 and the other network interface is assigned the IP address 192.168.1.102.

LAN = local area network, the network on your side of the router. WAN = wide area network, everything on the other side of the router.

The command is simply "route print", not "route /print", but you got it right since you saw the metrics.

LAN and WAN are again misused here, but you're correct that one interface (with the lower metric) is given priority over the other interface (with the higher metric).

The actual metric values are unimportant. The important thing is their values relative to each other.

I was accidentally using WAN to mean the wireless area network and the LAN to be the wired network but I do see what you mean.

So this seems to work to tell which network interface card is being used when there are more than one network interface cards:

(1) Run "ipconfig /all" to figure out which network interface card is associated with each IP address

(2) Run "route print" to figure out which IP address has the lowest metric (the first two lines of the output).

(3) The IP address with the lowest metric is the one being used; the other IP address is not being used.

Did I get it right this time?

Good.

Good.

I'd rewrite that to say, "The network interface with the lowest metric is the one being used by default." Other network interface(s) would be used if specific route statements apply to them.

Very good.

• you can control what per-connection route metric is used in the adapter's Properties panel (TCP/IP properties ->

Advanced -> IP Settings -> Uncheck Automatic metric)

• you can also control this in the DHCP server for the clients, using option 43 ... the option is specified thus:

0x2b option 43 length of the remaining of the option

0x03 "MS default router metric base option subcode" 0x04 suboption length metric value as a series of 4 bytes

So to set the default router metric to 3, then set option 43 to

0304.0000.0003

Cheers,

Aaron