How to make Ethernet over USB work with Win2K professional

Back to Neil's Zaurus page.


I've only used this with Windows 2000 Professional but it should work for any other windows OS.
You will need:
1) A Zaurus
2) A PC with an internet connection, dialup or broadband should be fine.
3) Some windows proxy software. I am using CCProxy but any half decent proxy will do the trick. Note that it will probably need to be able to proxy DNS requests, not all do.

Firstly the solution I haven't tried but that I suspect is the simplest solution and the one that most people will be able to use. It assumes that the PC that the Zaurus conencts to is your ICS gateway. i.e. It has a network connection (dialup or broadband) and the Internet Connection Sharing option has been ticked on the Sharing tab from the properties dialogue. Note: this is theory as my network is more complex, however as enabling ICS turns on IP forwarding any packets arring on any other net interface (Zaurus included) should be routed out of you internet connection.

My PC and what to do to yours
My network is more complex, My home LAN sits behind an SMB Barricade firewall/router. The PC therefore has its priomary NIC on the clean side LAN of the Barricade (192.168.2.0), you cannot enable ICS because this forces the interface to be 192.168.0.1 (stupid MS) and would therefore prevent connection to the Barricade! Win2K professional does not support proper routing (though Win2K server does) and as such the only way to get the packets from the Zaurus interface to the outside world is by a proxy (in theory the etherbridge solution will do the same thing, but I have not used it).

Install your proxy software and set it up according to the instructions that come with it. Note that the proxy server should be listening on the Zaurus subnet (192.168.129.1 by default) otherwise packets won't reach it!

On the Zaurus
go to the Settings select network/sync, I made sure that no services were available(I deleted any TCP/IP LAN entries that I had inadvertantly created during the learning process).

In the Services tab create a new service of type USB - TCP/IP.
Select Specify TCP/IP Information
click the TCP/IP tab
In IP Address: type the IP of your sync address (you can check this on the PC settings of your intellisync software)
leave the rest as they are.
In DNS I covered both possibilities by adding the DNS service of the Barricade firewall as primary and the IP address of the proxy as the secondary.

Click the proxies tab
select Set proxies
set the two entries to the settings of your proxy server.

All is now ready.

You should be able to browse the web (though the default UK homepage doesn't seem to display!) and even install packages from the net once you've setup the feed.

An Addendum:
In the interest of completeness I just did a hard reset and started from scratch. To my horror it didn't work. This is what happened.
After the reset a quick synch brought back all the address book entries etc. This showed that the basic connectivity was working. So I dutifully added in a USB network service as described in my instructions above. Uh Oh, it doesn't work. opera can't get out, I can't ping in and worse still it doesn't sync any more.

A little investigation identified the problem. There appears to be a bug in either the desktop or the Z sync default config because the two don't agree.
The desktop Intellisink software shows the IP of the USB based device as 192.168.129.201, a quick look at the ipconfig on the NT box will show that the PC end of the interface is 192.169.129.1
The Zaurus Sync settings show the IP as 192.168.129.1, now I simply assumed that this was identifying the remote side of the link and thus was correct, and indeed initially it works. However if you define a network connection using this knowledge as a basis (remote proxy 192.168.129.1 local Z IP 192.168.129.201) This upsets the config in some way and it will not work unless.......
You manually set the sync IP for USB to be 192.168.129.201 as well. If anyone knows why this is, please let me know.



Neil