Hardware Internet Sharing

Hi there,

Homechoice is driving me insane.

The problem I am having is that I have only one IP address to connect
to the Internet with. The setup at the moment is as follows:

Adsl modem (provided by Homechoice) connected to telephone socket at
one end, and to router via ethernet. The router then connects the
other pcs in the house.

The issue is in DHCP. If DHCP is turned on in the router, the network
works fine, but I have no access to the internet. I am assuming it is
because the router tries to assign an IP address to the modem as well,
which it can't do, meaning that the modem isn't seen on the network.

If DHCP is turned off, then I only have one IP address, assigned by
the ISP through the modem, to share between all my computers.

How do I get around this?

Unfortunately the ISP assigns dynamic IP addresses, meaning I can't
fix the IPs on my machines to access the internet.

Anyone got a clue?

Should I just forget about the internet and move to Cuba?


NickC

NickC <(E-Mail Removed)> wrote:
> Hi there,
>
> Homechoice is driving me insane.
>
> The problem I am having is that I have only one IP address to connect
> to the Internet with. The setup at the moment is as follows:
>
That's entirely normal.

> Adsl modem (provided by Homechoice) connected to telephone socket at
> one end, and to router via ethernet. The router then connects the
> other pcs in the house.
>
> The issue is in DHCP. If DHCP is turned on in the router, the network
> works fine, but I have no access to the internet. I am assuming it is
> because the router tries to assign an IP address to the modem as well,
> which it can't do, meaning that the modem isn't seen on the network.
>
I don't think it does assign an address to the router, at least not to
the 'outside world' side of the router. I think your problem lies
elsewhere, probably in the router configuration/set-up.


> If DHCP is turned off, then I only have one IP address, assigned by
> the ISP through the modem, to share between all my computers.
>
> How do I get around this?
>
> Unfortunately the ISP assigns dynamic IP addresses, meaning I can't
> fix the IPs on my machines to access the internet.
>
> Anyone got a clue?
>
What should be happening is NAT - Network Address Translation in the
router. On the 'internet' side of the router all your machines look
as if they have one IP address, the one assigned by your ISP when you
connect. On your ('intranet') side of the router each machine has its
own IP address which, almost always, will be one of the ranges of
'private' IP addresses. The most commonly used range is
192.168.1.xxx, these can be static (i.e. each machine has a fixed IP
address) or can be assigned by the router using DHCP. The router
'translates' the addresses on all packets that pass through it so that
all your machines feel as if they have their own personal access to
the Internet.

What range of addresses is the router using when assigning addresses
by DHCP?

Is NAT turned on in the router? (possibly called IP masquerading)

--
Chris Green

In article <(E-Mail Removed)>, NickC
<(E-Mail Removed)> writes
>If DHCP is turned off, then I only have one IP address, assigned by the
>ISP through the modem, to share between all my computers.

Is your modem perhaps also a router? If that is the case, then perhaps
what you need is a plain LAN switch and not a combined router/switch.

You might be able to simulate that by plugging the modem into one of the
LAN ports on the router/switch. Or I might be talking out of the back
of my head.

--
John Blundell

On Mon, 07 Feb 2005 10:31:48 +0000, NickC
<(E-Mail Removed)> strung together this:

>The problem I am having is that I have only one IP address to connect
>to the Internet with.

Not a problem, most people in the UK have only one IP address with
more than one machine behind it.

>The setup at the moment is as follows:
>
>Adsl modem (provided by Homechoice) connected to telephone socket at
>one end, and to router via ethernet. The router then connects the
>other pcs in the house.
>
>The issue is in DHCP. If DHCP is turned on in the router, the network
>works fine, but I have no access to the internet. I am assuming it is
>because the router tries to assign an IP address to the modem as well,
>which it can't do, meaning that the modem isn't seen on the network.
>
No, the LAN and WAN side of the router are totally independent of each
other. The WAN side of the nmodem picks up the IP address from your
ISP. The LAN side of the modem then either picks up a DHCP IP address
from the router or it can be fixed. This should be in a private
address range such as 192.168.1.*.
The WAN side of the router should have an IP address in the same
subnet as the modem LAN side, i.e. 192.168.1.*.
The LAN side of the router then needs a IP address range seperate from
the WAN side, such as 192.168.0.* and the PC's all connect to the
router in this range, either statically or by DHCP.

So, you will have

Modem WAN = DHCP (address picked up from ISP).
Modem LAN = IP address 192.168.1.1.
Router WAN = 192.168.1.2, gateway 192.168.1.1.
Router LAN = 192.168.0.1.
PC's on network = 192.168.0.2-254 with the gateway set as 192.168.0.1.
All the above, except the modem WAN, should have a 255.255.255.0
subnet.
--

SJW
Please reply to group or use 'usenet' in email subject

Thank you all for your answers.

Let me clarify a few points.

NAT is turned on in the router. The DHCP address range is 192.168.0.x,
where the router is 192.168.0.1.

I should also point out that the router has an integrated modem.

Now, when all the settings on the pcs are set to "automatically
detect", each pc is assigned an IP address in the 192.168.0.x range,
and the internet is to accessible. At this point, the modem, connected
to a LAN port, is not assigned an IP address. If I check the router's
attached devices, only the pcs are displayed.

If however I set, on one of the pcs, my ISP DNS servers, that PC is
assigned the ISP IP address (81.1.10x.x), and is therefore connected
to the internet. It is however not anymore connected to the intranet,
meaning I can't access the router settings and I can't see the other
pcs.

I'm getting really fed up with this. Is all of this happening because
of the integrated modem?

Thank you all very much for your help.



On Mon, 07 Feb 2005 16:17:33 +0000, Lurch
<(E-Mail Removed)> wrote:

>On Mon, 07 Feb 2005 10:31:48 +0000, NickC
><(E-Mail Removed)> strung together this:
>
>>The problem I am having is that I have only one IP address to connect
>>to the Internet with.
>
>Not a problem, most people in the UK have only one IP address with
>more than one machine behind it.
>
>>The setup at the moment is as follows:
>>
>>Adsl modem (provided by Homechoice) connected to telephone socket at
>>one end, and to router via ethernet. The router then connects the
>>other pcs in the house.
>>
>>The issue is in DHCP. If DHCP is turned on in the router, the network
>>works fine, but I have no access to the internet. I am assuming it is
>>because the router tries to assign an IP address to the modem as well,
>>which it can't do, meaning that the modem isn't seen on the network.
>>
>No, the LAN and WAN side of the router are totally independent of each
>other. The WAN side of the nmodem picks up the IP address from your
>ISP. The LAN side of the modem then either picks up a DHCP IP address
>from the router or it can be fixed. This should be in a private
>address range such as 192.168.1.*.
>The WAN side of the router should have an IP address in the same
>subnet as the modem LAN side, i.e. 192.168.1.*.
>The LAN side of the router then needs a IP address range seperate from
>the WAN side, such as 192.168.0.* and the PC's all connect to the
>router in this range, either statically or by DHCP.
>
>So, you will have
>
>Modem WAN = DHCP (address picked up from ISP).
>Modem LAN = IP address 192.168.1.1.
>Router WAN = 192.168.1.2, gateway 192.168.1.1.
>Router LAN = 192.168.0.1.
>PC's on network = 192.168.0.2-254 with the gateway set as 192.168.0.1.
>All the above, except the modem WAN, should have a 255.255.255.0
>subnet.

On Tue, 08 Feb 2005 16:32:38 +0000, NickC
<(E-Mail Removed)> wrote:

>Thank you all for your answers.
>
>Let me clarify a few points.
>
>NAT is turned on in the router. The DHCP address range is 192.168.0.x,
>where the router is 192.168.0.1.
>
>I should also point out that the router has an integrated modem.
>
>Now, when all the settings on the pcs are set to "automatically
>detect", each pc is assigned an IP address in the 192.168.0.x range,
>and the internet is to accessible. At this point, the modem, connected
>to a LAN port, is not assigned an IP address. If I check the router's
>attached devices, only the pcs are displayed.
>
>If however I set, on one of the pcs, my ISP DNS servers, that PC is
>assigned the ISP IP address (81.1.10x.x), and is therefore connected
>to the internet. It is however not anymore connected to the intranet,
>meaning I can't access the router settings and I can't see the other
>pcs.
>
>I'm getting really fed up with this. Is all of this happening because
>of the integrated modem?
>
>Thank you all very much for your help.
>
>
<snip>
>>Modem WAN = DHCP (address picked up from ISP).
>>Modem LAN = IP address 192.168.1.1.
>>Router WAN = 192.168.1.2, gateway 192.168.1.1.
>>Router LAN = 192.168.0.1.
>>PC's on network = 192.168.0.2-254 with the gateway set as 192.168.0.1.
>>All the above, except the modem WAN, should have a 255.255.255.0
>>subnet.

I think Lurch's response (after snip) agrees with what I thought, but
your post changes that slightly.

Am I correct in thinking you have a modem/router connected to a modem?

If so, why not connect the modem/router to the line and dispose of the
modem?

Alternatively, you will only be able to use the router as a switch (no
NAT etc), which is why only one PC connects to the internet when you
turn the router DHCP off. With a dynamic IP address from the ISP, the
option to use one system as a proxy for the others is not available
through one connection (as you would have to use the ISP's address
range). In this case, the only option would be to add a second card to
one system to use as a proxy and then connect that to the modem and
the router (switch) on seperate interfaces using a fixed address for
the proxy system.

HTH


PeeGee
--
The reply address is a spam trap. If you need to reply directly, put the UK where it should be - first.

>Am I correct in thinking you have a modem/router connected to a modem?
>
>If so, why not connect the modem/router to the line and dispose of the
>modem?

That's Homechoice for you!

They send TV signals down the telephone line, and everything has to go
through the box. There's not other way.

I'll probably get rid of the router/modem and get a broadband router.

Thanks for your help.

In message <(E-Mail Removed)>, NickC
<(E-Mail Removed)> writes
>Hi there,
>
>Homechoice is driving me insane.
>
>The problem I am having is that I have only one IP address to connect
>to the Internet with. The setup at the moment is as follows:
Provide model numbers for the router and modem, it makes life easier to
understand if we know what the kit is and how it is likely to have been
configured, we might even be able to tell you exactly how to reconfigure
it.
--
Clint Sharp

On Tue, 08 Feb 2005 16:32:38 +0000, NickC
<(E-Mail Removed)> strung together this:

>I'm getting really fed up with this. Is all of this happening because
>of the integrated modem?
>
I'd have thought so. Why do you want to use another modem other than
the one built into the router? Either use a router and seperate modem,
or use a router\modem combo jobby.

A router will have WAN and LAN ports, the WAN port will connect to the
modem and the router will direct trafic between the WAN and LAN.

A router\modem has WAN and LAN ports, the WAN port will connect
directly to the inernet and the router\modem will direct traffic
between the WAN and LAN ports.

With your setup the router\modem receives a request from the LAN to go
out to the internet, it will then try and forward that request to the
WAN port, which obviously isn't connected to the internet.

When you connect directly to the internet by telling your PC to
connect through the modem as there is no router it is picking up the
WAN IP address and shutting off access to all the other PC's, and
because it's in a completely different, more secure subnet, then it
can't integrate all theat well with the network.

If you could please give more detail about what you're trying to do,
and why, and preferably *ALL* of the information then we might bwe
able to offer some more specific advice.
--

SJW
Please reply to group or use 'usenet' in email subject

On Tue, 08 Feb 2005 19:07:54 +0000, NickC
<(E-Mail Removed)> strung together this:

>
>>Am I correct in thinking you have a modem/router connected to a modem?
>>
>>If so, why not connect the modem/router to the line and dispose of the
>>modem?
>
>That's Homechoice for you!
>
Ah, some more facts creeping out then.

>I'll probably get rid of the router/modem and get a broadband router.
>
You want a cable router, i.e. one with no modem.
--

SJW
Please reply to group or use 'usenet' in email subject