I was forced to change broadband technology from POTS ADSL (slowband) to 2 way satellite. I am still getting used to the latter but it works fine.

I am now digging in to detail, specifically DHCP and IP address assignment -

On my ADSL my Netgear router acted as my private network DHCP server, assigning IP addresses on the private network using 192.168.0.x. So, each of my PCs was given an address like - 192.168.0. 2 or 3 or 4 or 5. The color network laser I forced to a private network IP address of 192.168.0.7.

The new modem for the 2 way satellite I thought works the same way, only the private network address is 192.168.100.x.

When I look at each of the PC network connections (Win XP32 bit) I see the assigned DHCP IP address is the same and is the external address I have been assigned for Internet access.

Has anyone else seen this type of IP addressing before?

Just curious, as everything seems to work as before, only faster. The only two issues I see is (1) My network laser will not work because of an Internet IP address; and, (2) any UK media content I want to download (legitimately) will be blocked as my external IP address is outside Truino in Italy, where the satellite base station is.

I have been given a UK proxy site for the last issue but I am finding it difficult to get it to work.

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It's good to be back amongst friends and colleagues

IP adresses are defined in RFC 1918. NB - we're talking IPv4 only here, IPv6 is a whole new issue altogether.

In brief, and relating it to your situation:

192.168.xxx.zzz is one of the 'private' address spaces reserved for local use. These addresses are 'non-routable' - they won't be passed through the internet backbone routers. Any address you might use internally will be translated to your single public IP address - the one which appears to be in Italy - before it is sent over the internet, and any reply will be translated back to the local address of the originating computer. That's the job of the "NAT" function within your router - and incidentally, confirms that your satellite device is a router, not just a modem.

192.168 is usually used for "Class C" addresses - blocks of 256 (maybe 255 usable) addresses which are visible to each other, but kept private from each other. You can recognise this by the associated "subnet mask" - you'll see this alongside every IP address, but you usually don't have to worry about it, because it's assigned and maintained automatically through DHCP. In your case I'm pretty certain that it will be 255.255.255.0 for both address ranges (before and after the switchover).

This means that 192.168.xxx.zzz is treated as being completely separate from 192.168.yyy.zzz - they can't speak to (are kept private from) each other. Useful when differnt households or different companies are sharing a common internet access facility - say if you did a deal with your neighbours to share the satellite.

In practical terms, just give your printer a new fixed IP address anywhere in the 192.168.100.ppp range. It would be 'best practice', if your new satellite router allows this degree of control, to -

either: look at the DHCP 'scope' defined in the router - usually, it won't allocate the full 255 possible addresses, but have a limited range with a starting number (perhaps 10) and an ending number (perhaps 200). Give the printer an address in one of those blank, unused, areas.

or: if the router thinks it's free to assign any of the 255 possible addresses, it should be possible to 'reserve' one of them for a specific device to use - usually by entering the 'MAC' address of the device (think of it as a hardware serial number - it should be printed on a sticker round the back of the printer). Looks for a format like 01:23:34:56:78:9A - six goups of two hex digits each. Sometimes the separator is '-' instead of ':'. If you 'reserve' the address, you can save yourself grief in the future - if you get a new device in the future, and the router DHCP tries to assign it the same address as you've chosen for the printer, everything goes pear-shaped.

HTH.

I was forced to change broadband technology from POTS ADSL (slowband) to 2 way satellite. I am still getting used to the latter but it works fine.

... The new modem for the 2 way satellite I thought works the same way, only the private network address is 192.168.100.x.

When I look at each of the PC network connections (Win XP32 bit) I see the assigned DHCP IP address is the same and is the external address I have been assigned for Internet access.

Has anyone else seen this type of IP addressing before? ...

Yep.

That is typical of using a modem as opposed to a "modem/router". You'll likely get very confused results if you try connecting multiple devices to it!

An easy fix should be for you to connect a (wireless) router/firewall to the satellite modem and then connect all your home machines to the router:

\
+|.....Modem.....Router..... PC1
/                   ||..... PC2
                    |..... Laser printer

.... And so on.

I'm surprised you didn't get a diagram for that with your new install.


Also note that you cannot connect to both your satellite and your adsl at the same time, not unless your satellite kit does that for you, or you already know the low-level workings about packet routing.


Let us know how you get on with it.

Then tell Ofcom how unusable ADSL is!

Good luck,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Re-reading, I'm slightly confused now. The 192.168.100.x addressing suggested an active DCHP server somewhere on the network - Windows autocinfig addresses would be different (169... somewhere).

But I agree with Martin - if the XP machines are all showing the same IP, and it's an external one, then maybe the box they're connecting to is a modem only. There's a bit of a contradiction there - I think we need more info, John.

I think I confused readers by quoting the private network, and DHCP assignment, for my ADSL Netgear router. My apologies, but it was to try and illustrate my expectations.

Now to add more detail, and try and clarify Richard's confusion.

The satellite equipment installer (Avonline/Tooway) only mentioned the connector as a modem, but he did say it had DHCP capability.

As a result I expected to be able to see that all my attached devices had been assigned an private network IP address.

Back to the Netgear ADSL router first. When I accessed the Netgear ADSL router's browser address (at 192.168.0.1) I was able to see in the menu options all the IP addresses of the attached devices, including the network laser.

And now the satellite modem.I entered the satellite modem's browser window (192.168.100.1) expecting to see a similar range of menu options. But, this is restricted only to the modem itself and the satellite dish (technical performance elements). There is no menu options for assigned private network IP addresses to any of my PCs, the SamKnows performance trial modified router or the network laser.

ATM I have only 2 of my PCs running, and the Local Area Connection windows shows the external IP address as the PCs one (each individual PC).

As a result of this I am assuming the DHCP side of the satellite modem actually passes the Internet IPv4 address through to all attached devices.

NOTE: The satellite modem has the following connectors at the back - (a) a power on/off line; (b) a satellite dish connector (coaxial) for the down and up satellite links; and finally, (c) a single 100Mbps Ethernet link, which I have attached to a multi-port 10/100Mbps switcher.

New Question:

Following ML1's diagram -

Satellite dish ... satellite modem ... router ... PC1/PC2/etc

I presume I could use the Netgear router as the DHCP address assignment device?

As the router will not be connected to the ADSL/Internet, I presume I can plug the Ethernet out from the satellite modem in to, say, port 1 of the Netgear router. This would then provide the Ethernet links.

Further, I can then take another Ethernet link, from the Netgear router using any one of the 3 remaining empty Ethernet ports, and attach it to my multi-port switcher (with all the attached devices).

I assume the DHCP capability of the Netgear router would then assign appropriate private network IP addresses (in the 192.168.0.x series) to each of the attached devices?

Hope this doesn't seem too complex???

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It's good to be back amongst friends and colleagues

I *think* I understand a little.
I would:
Come out of the satellite modem and into the 'Internet port', not a LAN port, on the Netgear router. Then out of the router to the various PCs and switch from the LAN ports.

Leave DHCP enabled on the Netgear router, and select "Get IP Dynamically from ISP" which will be the DHCP server in the satellite modem. The satellite modem will give the Netgear router a 192.168.100.x address, the router will give everything connected on the LAN ports a 192.168.0.x address. You might have to select "Get DNS automatically from ISP" if it don't select itself.

Not sure about switches though, I've never had to use one. Will the router continue to give separate addresses to things plugged into the switch? If it does you should be good to go. You should be able to see everything connected to the router from the router control panel.

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</Tazz>

This seems odd.

You say that the satellite modem's control interface has the IP address 192.168.100.1

Using standard RFC 1918 conventions, I would expect that address only to be visible to a computer with an assigned (or manually entered) IP address in the range 192.168.100.xyz and subnet mask 255.255.255.0 (sometimes written 192.168.100.xyz/24 for compactness).

Maybe (and I'm guessing here) it assigns compatible IP addresses using its own internal DHCP server when first powered up, to facilitate initial setting up and configuration. And then - once it has locked on to the satellite signal - it switches mode, turning off the internal DHCP and instead passing through the external IP address obtained from the DHCP server running in the satellite base station in Italy. I would expect that sort of thing to be covered by the installers or in a manual somewhere. Does this modem have a maker's name and model number - there might be a PDF version on a website somewhere we could pore over together.

As to using your existing Netgear device - probably not. I assume it's the standard sort of domestic/SoHo device with an ADSL modem/router/switch all housed in a single unit? Again, a model number would confirm.

Your problem is that you want to run multiple computers - each of which must have a unique IP address - over an external link with only one IP address. That can only happen if you have a NAT (Network Address Translation) device between the computers and the modem. An ADSL router provides NAT, but only between the LAN and the ADSL port, not between the ethernet (LAN-only) ports.

You may find that you need to equip yourself with the other sort of router like the RP614 - just an example from the Netgear range - designed to work with an external modem, typically on combined cable-TV-and-internet services.

I *think* I understand a little.
I would:
Come out of the satellite modem and into the 'Internet port', not a LAN port, on the Netgear router. Then out of the router to the various PCs and switch from the LAN ports.

Leave DHCP enabled on the Netgear router, and select "Get IP Dynamically from ISP" which will be the DHCP server in the satellite modem. The satellite modem will give the Netgear router a 192.168.100.x address, the router will give everything connected on the LAN ports a 192.168.0.x address. You might have to select "Get DNS automatically from ISP" if it don't select itself.

Not sure about switches though, I've never had to use one. Will the router continue to give separate addresses to things plugged into the switch? If it does you should be good to go. You should be able to see everything connected to the router from the router control panel.

Yes, I think we're saying the same thing here. The trouble is, he'll need to use, as you say, an 'internet' or 'WAN' port for an ethernet (RJ45) connection. See the back view of the RP614 I linked. But I expect John will have an RJ11 ADSL jack instead of the 'Connects to Broadband modem' jack in that view.

Adding a switch is the least complicated component. If the (typical) four LAN ports on the router aren't enough, simply patch one of them to an ethernet switch, and patch the computer to that. It simply expands the number of available ports, and - on this scale - will require no configuration, and very few pounds/dollars.

Yes Richard.

The Netgear router is a DG834PN wireless ADSL router with built in DHCP and hardware firewall. The wireless is switched off.

Also the 2 way satellite modem has only 1 Ethernet port, and a USB port.

What I was hoping, from ML1's suggestion and my ramble earlier, was the satellite modem would pass the external IP to the Netgear Router (or another Netgear device like the RP614. The Netgear router, or other device, would then assign private network IP addresses (of it's own designation not the modem's 192.168.100.xx) to the attached devices.

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It's good to be back amongst friends and colleagues

I agree with Richard and ML1. You'll most likely find that the
"wan" port that went to your old adsl modem will connect with your
satellite modem just fine. I have a linksys that is labeled as an adsl
router that I'm using with a cable modem.

Put it this way, it doesn't hurt to try! :)
Worst case, it doesn't work and you have to put things back the way they are
right now.


Good Luck!

Kevin

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"Two things are infinite: The universe and human stupidity; and I'm not sure about the universe." - Albert Einstein

I had a similar problem about 12yrs back when I use to live in Sydney and had a cable connection.

The cure in my case was to add a second nic to my PC so that the modem directly connected to my PC, then I enabled internet sharing, then connected the second nic to my network switch so that the other PC's could get out.

Cheers.

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I had looked around a bit, and it is for sure that this modem has a build in DHCP, so no need for an extra one.
So its easy installation line -> Sat-Dish->Modem->Hub/Switch-> many computers.

If u cant find the ip-adress of your printer, this might help: Network Scanner

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- Performance is not a simple linear function of the number of CPUs you throw at the problem. -

The satellite equipment installer (Avonline/Tooway) only mentioned the connector as a modem, but he did say it had DHCP capability.

It is a modem. Nothing more. It will forward DHCP requests, nothing more.

As a result of this I am assuming ... the satellite modem actually passes the Internet IPv4 address through to all attached devices.

Yes, everything.

NOTE: The satellite modem has the following connectors at the back - (a) a power on/off line; (b) a satellite dish connector (coaxial) for the down and up satellite links; and finally, (c) a single 100Mbps Ethernet link

Yep, it's a modem.

which I have attached to a multi-port 10/100Mbps switcher.

VERY BAD. Wrong. Don't do that.

Satellite dish ... satellite modem ... router ... PC1/PC2/etc

That's what you should do.

I presume I could use the Netgear router as the DHCP address assignment device?

ONLY IF, and ONLY IF, your whatever-modem/router explicitly has an ethernet port marked on it with the letters WAN. No other ports will work correctly for connecting to a WAN (the satellite modem).

As the router will not be connected to the ADSL/Internet, I presume I can plug the Ethernet out from the satellite modem in to, say, port 1 of the Netgear router. This would then provide the Ethernet links.

No, don't do that. It doesn't work as you might hope.

Further, I can then take another Ethernet link, from the Netgear router using any one of the 3 remaining empty Ethernet ports, and attach it to my multi-port switcher (with all the attached devices).

No, don't do that. Very bad.

I assume the DHCP capability of the Netgear router would then assign appropriate private network IP addresses (in the 192.168.0.x series) to each of the attached devices?

It will, but that will then also be transmitted to the entire internet. You'll generate lots of network errors that either the modem will block, or you'll get cut off.


As shown in the diagram, you need a dedicated router with an ethernet WAN port. You then connect all your LAN devices to the LAN ports.


As a stop-gap to get onto the internet, you can connect ONE PC (and ONLY ONE PC) directly to the satellite modem. That PC is then directly connected to the internet and it should pick up an internet IP assigned by DHCP from your satellite ISP.

If you want any more devices connecting to the internet, then you can either use a second connection on the PC and use "internet connection sharing", or you must get a router.

A network switch is NOT a router.

Routers usually include a network switch/hub to give you multiple LAN ports.

Sorry, but you need to have a router. An ADSL-only-modem/router is useless for that configuration.


Hope that helps,

Good luck,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Martin, I agree totally with what you've just posted.

But I've been chatting with John by PM, and he tells me that the two XP32 machines in his opening post have actually been assigned IP addresses which differ by one digit in the final octet - that suggests that his service contract allows multiple machines to be connected, although we don't know the exact limit yet. But it still seems that a local 'cable' router (with ethernet WAN port) would be a quick and easy - and these days cheap - solution. Personally, I'd much prefer that to the ICS alternative - if only because that would require the ICS machine to be active and reliable at all times, for any of the others to access the net. I prefer dedicated hardware for that role.

Edit - a local hardware router would also provide a firmware firewall covering all machines, whereas an ICS connection would expose the ICS machine directly to the internet, and require it to act as firewall to the others.

Good comment just come in:

i would only point to this article:
http://en.wikipedia.org/wiki/Tooway

"The IDU is a satellite modem providing a plug-and-play Ethernet interface[9] with DHCP. Current version is manufactured by ViaSat. A WiFi router may be connected to the satellite modem in order to deploy wireless Internet access in the home. No software is required on the computer"

cant say more to it, but it realy seems to be a "dual machine" modem + dhcp

Read the wording carefully. The "DHCP" bit is misleading even if it has it's own DHCP capability (makes sense to avoid chatter over the high latency expensive satellite link). The device still acts as a "simple modem". Hence the follow-on phrase: "A ... router may be connected to the satellite modem in order to deploy ... Internet access in the home."


Looks very much like a modem still. It's even described as a modem. You MUST use a WAN -> LAN router (with it's own DHCP and NAT) if you want to run multiple devices on a local network (LAN).

Ethernet routers can be picked up for as little as £15 or so.


Hope that helps,

Good luck,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

... But I've been chatting with John by PM, and he tells me that the two XP32 machines in his opening post have actually been assigned IP addresses which differ by one digit in the final octet ...

Often, ISPs allow two MAC addresses to connect on one modem for a certain time window. That allows you to make one change to what device you connect yet stops you from running multiple machines grabbing multiple internet IPs.

Might be that he can get away with connecting two PCs directly to the internet. However, that is not normally done unless you're on a "business" type link. If you were able to do that, you explicitly get told how many IP addresses you can grab.

Edit - a local hardware router would also provide a firmware firewall covering all machines, whereas an ICS connection would expose the ICS machine directly to the internet, and require it to act as firewall to the others.

The dedicated router is the best way to go, for many reasons.


Good luck,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

... So its easy installation line -> Sat-Dish->Modem->Hub/Switch-> many computers. ...

Just to avoid confusing others: Sorry, that is wrong. Does not work as intended. Don't do it.


Check out the explanations already given earlier.

Good luck,
Martin

---

See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

Yes, I think we're saying the same thing here. The trouble is, he'll need to use, as you say, an 'internet' or 'WAN' port for an ethernet (RJ45) connection. See the back view of the RP614 I linked. But I expect John will have an RJ11 ADSL jack instead of the 'Connects to Broadband modem' jack in that view.

Adding a switch is the least complicated component. If the (typical) four LAN ports on the router aren't enough, simply patch one of them to an ethernet switch, and patch the computer to that. It simply expands the number of available ports, and - on this scale - will require no configuration, and very few pounds/dollars.

OK, I see, my bad. I ASSuMEd that the Netgear router was just a router and the modem was separate, like my Netgear WPN824 v1.

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</Tazz>

Satellite dish ... satellite modem ... router ... PC1/PC2/etc

That's what you should do.

It's also what they tell you to do in the (very minimized) Tooway FAQ:
Can I integrate Toowayâ„¢ into a network?
Yes, you simply need to connect an IP Router between the network in your home and the satellite modem.

Also:
Can I use a wireless home network with Toowayâ„¢?
Yes, a Wi-Fi home network is available with Toowayâ„¢ at a low additional cost. Alternatively, any Wi-Fi router can be connected to the Toowayâ„¢ modem, allowing you to enjoy wireless browsing.

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... But I've been chatting with John by PM, and he tells me that the two XP32 machines in his opening post have actually been assigned IP addresses which differ by one digit in the final octet ...

Often, ISPs allow two MAC addresses to connect on one modem for a certain time window. That allows you to make one change to what device you connect yet stops you from running multiple machines grabbing multiple internet IPs.

Might be that he can get away with connecting two PCs directly to the internet. However, that is not normally done unless you're on a "business" type link. If you were able to do that, you explicitly get told how many IP addresses you can grab.

Edit - a local hardware router would also provide a firmware firewall covering all machines, whereas an ICS connection would expose the ICS machine directly to the internet, and require it to act as firewall to the others.

The dedicated router is the best way to go, for many reasons.


Good luck,
Martin

Looking at the PDF for his ADSL modem, it does say it has a WAN port.

Physical Interfaces:
- LAN Ports: Four (4) 10/100 Mbps auto-sensing, Auto
Uplinkâ„¢ RJ-45 ports (one Cat 5 UTP cable included),
802.11g access point and Super G
-WAN Port: ADSL RJ-11, T1.413, G.DMT, G.Lite,
ITU Annex A; Annex B version is DG834PNB

So it should be able to handle the router duties.

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