[Q] Peer-to-peer with Windows XP + Internet Connection Sharing

[Wim VAN PAEPEGEM]

Dear all,

I have a home computer with Windows 2000 SP4 installed and an ADSL USB
modem to dial-up to the Internet. My laptop from work has Windows XP
Professional SP2 installed. If I bring home my office laptop, I would
like to share files between these two computers and share the ADSL
internet connection of my home computer.
I have no hub, but a crossover UTP cable between the Ethernet cards of
both computers.
I have several questions:
1) do you need a hub for this set-up, or can I manage with the crossover
cable ?
2) before, I used the NetBEUI protocol to share files between two
Windows 2000 computers, but this protocol is not supported anymore. If I
connect now my Windows 2000 home computer to my Windows XP office laptop
through the crossover UTP cable, my Windows XP laptop does not find my
home computer. I have switched off the Windows XP firewall.
At work, my office laptop is configured for DHCP.
How can I take the first step to share files ?
3) how do I setup the internet connection sharing ? The Internet
connection sharing between my home computer and my office laptop should
go through the LAN connection with the crossover UTP cable, but if my
ADSL modem is active, my "Network and dial-up connections" window in
Windows 2000 shows also a LAN connection "ATM connection" for my ADSL
line. Then there is the other "Local Area Connection". Which ones do I
need to share ?
Which TCP/IP settings do I need for my Windows XP office laptop ?

I already searched through the newsgroups and the website
practicallynetworked.com, but I am afraid I need a more
easy-to-understand description of the different steps I should take.
Can anybody give some suggestions or point me to a relevant website ?

Best regards,
Wim Van Paepegem
(e-mail address removed)

 

[Kurt]

1) do you need a hub for this set-up, or can I manage with the crossover

cable ?

If you just have to two computers, a crossover cable will do just fine.

2) before, I used the NetBEUI protocol to share files between two Windows
2000 computers, but this protocol is not supported anymore. If I connect
now my Windows 2000 home computer to my Windows XP office laptop through
the crossover UTP cable, my Windows XP laptop does not find my home
computer. I have switched off the Windows XP firewall.
At work, my office laptop is configured for DHCP.
How can I take the first step to share files ?

You can install NetBEUI if you like, but since you want Internet access,
you'll have to configure TCP/IP anyway, so may as well just bire the bullet
and forget about NetBEUI.

The first step since you want to share Internet, is to be sure your USB
Modem has not assigned you an IP address on the 192.168.0.0 network. To
check this, open a command prompt and type "ipconfig /all | more" at the
command line. You should be able to identify your USB connection because it
will have an IP address other than 169.254.something. As long as it is not
192.168.0.something, the rest is easier If it IS 192.168.0.something, it can
still be done, but it involves a few more steps. For now let's assume it's
something else (probably something starting with 192.168).

The next step is to enable ICS. Go to network settings (from control panel)
and right-click your USB connection - click "Properties" in the context
menu. When the properties page opens, select the advanced tab and check the
bos to enable ICS. DOn't worry about other settings for now. You should get
a message telling you that the LAN Network Interface will be gven the IP
address of 192.168.0.1. That's it for that end.

On the work machine, make sure the "Local Area Connection" is set to get
it's IP address and DNS server settings automagically (DHCP) and re-boot it.
When it comes back up, open a command prompt and type "ipconfig". You should
have an IP address of something like 192.168.0.2 subnet mask 255.255.255.0
and gateway of 192.168.0.1. If you do, yhou should be surfing.

3) how do I setup the internet connection sharing ? The Internet
connection sharing between my home computer and my office laptop should go
through the LAN connection with the crossover UTP cable, but if my ADSL
modem is active, my "Network and dial-up connections" window in Windows
2000 shows also a LAN connection "ATM connection" for my ADSL line. Then
there is the other "Local Area Connection". Which ones do I need to share
?

You only need to share the ATM connection.

Which TCP/IP settings do I need for my Windows XP office laptop ?

If ICS is set up correctly, just set the laptop to obtain settings
automatically.

This will also allow you th share files as long as you account for
permissions (file and share level).

....kurt

 

[Wim VAN PAEPEGEM]

Dear Kurt,

Thank you very much for your prompt response. I have followed your
instructions, but it does not work :-( (although there is progress !).

First I have checked the ADSL connection on my home computer (before
connecting my laptop through the crossover cable). It looked like this:

C:\>ipconfig /all

Windows 2000 IP Configuration

Host Name . . . . . . . . . . . . : wisi
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Broadcast
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Media State . . . . . . . . . . . : Cable Disconnected
Description . . . . . . . . . . . : SiS 900-Based PCI Fast
Ethernet Adap
ter
Physical Address. . . . . . . . . : 00-0C-6E-07-27-45

PPP adapter ADSL USB Modem Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 217.136.121.162
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 217.136.121.162
DNS Servers . . . . . . . . . . . : 195.238.2.21
195.238.2.22


Next, I have connected the crossover UTP cable and I have shared the ATM
connection. I have rebooted the ICS host and then the ipconfig output
looked like this:

C:\>ipconfig /all

Windows 2000 IP Configuration

Host Name . . . . . . . . . . . . : wisi
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Broadcast
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : SiS 900-Based PCI Fast
Ethernet Adap
ter
Physical Address. . . . . . . . . : 00-0C-6E-07-27-45
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.0.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
DNS Servers . . . . . . . . . . . :

PPP adapter ADSL USB Modem Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 80.201.233.50
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 80.201.233.50
DNS Servers . . . . . . . . . . . : 195.238.2.21
195.238.2.22

Next I have rebooted the laptop (Windows XP) and the LAN connection
indeed showed enabled. The ipconfig output on the laptop was as follows:

C:\Documents and Settings\Administrator>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : leonardo
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Mixed
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Broadcom NetXtreme 57xx
Gigabit Controller
Physical Address. . . . . . . . . : 00-15-C5-15-9D-1F
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.0.69
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.0.1
DHCP Server . . . . . . . . . . . : 192.168.0.1
DNS Servers . . . . . . . . . . . : 192.168.0.1
Lease Obtained. . . . . . . . . . : Tuesday, August 08, 2006
7:04:13 PM
Lease Expires . . . . . . . . . . : Tuesday, August 15, 2006
7:04:13 PM

Ethernet adapter Wireless Network Connection:

Media State . . . . . . . . . . . : Media disconnected
Description . . . . . . . . . . . : Intel(R) PRO/Wireless
3945ABG Networ
k Connection
Physical Address. . . . . . . . . : 00-13-02-BC-7C-B2


If I searched for the other computer by IP-address in Windows Explorer,
I managed to browse files on the other computer (it didn't work first,
but my ZoneAlarm firewall had refused the connection).
So far, so good. However, when I start Internet Explorer on my laptop, I
cannot open any websites (although I switched off the Windows XP firewall).

So, sharing files is ok, but sharing the internet connection does not
work. I wonder if it has anything to do with the following:
The ICS host (the Windows 2000 machine) allows me to share the ATM
connection directly, but if I try to share the ADSL USB connection, it
does not work.
In the "Network and dial-up connections" dialogue, I see the following
lines:

Name Type Status
------------------------------------------------------------
ADSL USB modem connection Dial-up Connected
ATM Connection LAN Enabled
Local Area Connection LAN Enabled

So, the ATM connection is shared, but if I right-click on the ADSL USB
modem connection and I try to enable ICS for the local network "ATM
Connection", the message is:
"Internet Connection Sharing is currently enabled for connection "ATM
Connection". It will now be enabled for connection "ADSL USB Modem
Connection" instead".
If I click OK, I get the error message:
"Cannot enable shared access. Error 783: Internet Connection Sharing
cannot be enabled. The LAN connection selected as the private network is
either not present, or is disconnected from the network".

I also tried the other option: to share the ADSL USB modem connection
for the local network "Local Area Connection". Then there is no error
message, but accessing websites on the laptop, does not work either.

Another reason that I thought of, is that the "Local Area Connection" on
the Windows 2000 ICS host has no DNS servers defined. Therefore I tried
to access web servers on my laptop by their IP address, but that does
not work either.

Do you have any idea what could be the reason ?

By the way, if I want to share files and I search for the laptop, I
first have to check his IP-address, because one time it is 192.168.0.69,
and the other time it is 192.168.0.120.
Is there a way to address both computers by their names (wisi and
leonardo) instead of searching for their IP-address in Windows Explorer ?

Best regards,
Wim
(e-mail address removed)

 

[Kurt]

You might have to play around with that a bit. It appears you got ICS set up
and the DHCP server service is functioning. Try pinging 217.136.121.162.
What happens?

....kurt

 

[Wim VAN PAEPEGEM]

You might have to play around with that a bit. It appears you got ICS set up
and the DHCP server service is functioning. Try pinging 217.136.121.162.
What happens?

Dear Kurt,

Pinging the IP-address 217.136.121.162, works ok.
In the mean time, I have tried out some things, and now surfing websites
works, but I do not understand why.
Yesterday, I installed a Virtual Private Network on my office laptop to
connect to the server at work. When I tried out the Internet Connection
Sharing again this morning and I started Internet Explorer on my office
laptop, he asked me to dial-up the VPN connection. I agreed to do so,
and guess what, I could surf to any site I wanted to.
So, strangely enough, my office laptop needs the VPN connection to
"recognize" the Internet Connection Sharing. And the VPN connection is
definitively running through the crossover cable. If I disconnect the
cable, I loose my Internet connectivity.
I then tried to define a new VPN connection with the IP address of the
server being 192.168.0.1 (the IP-address of my home computer), but that
does not work.
Do you understand how this works, and can it give an indication how it
should work without the VPN connection ?
My ipconfig output on the office laptop now looks like:

C:\Documents and Settings\Administrator>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : leonardo
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Mixed
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Broadcom NetXtreme 57xx
Gigabit Controller
Physical Address. . . . . . . . . : 00-15-C5-15-9D-1F
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.0.120
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.0.1
DHCP Server . . . . . . . . . . . : 192.168.0.1
DNS Servers . . . . . . . . . . . : 192.168.0.1
Lease Obtained. . . . . . . . . . : Wednesday, August 09, 2006
09:48:03
Lease Expires . . . . . . . . . . : Wednesday, August 16, 2006
09:48:03

Ethernet adapter Wireless Network Connection:

Media State . . . . . . . . . . . : Media disconnected
Description . . . . . . . . . . . : Intel(R) PRO/Wireless
945ABG Network Connection
Physical Address. . . . . . . . . : 00-13-02-BC-7C-B2

PPP adapter UGent:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 157.193.1.53
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 157.193.1.53
DNS Servers . . . . . . . . . . . : 157.193.40.42
157.193.71.1

Best regards,
Wim

 

[Kurt]

Sorry, but that really doesn't add up. In order to have a VPN connection,
you first must have an Internet connection. I would suspect that you are
using the default gateway and DNS servers on the remote network (unless you
specifically configured the VPN connection to NOT use them). That would hint
at this being a DNS issue (When you hit the office, you're specifying an IP
address, but when you hit a web site, you need o resolve the IP address from
it's URL). Try specifying your DNS servers manually in your Network
properties on the laptop and see if that gets you surfing without having the
VPN connected.

....kurt