Modem/router for use on VM cable?

[labougie]

Questions from a dummy, sorry about this! I'm on VM cable "M" with a Motorola Surfboard - only one ethernet port. I've just acquired a Siemens C460IP VOIP phone which also requires an ethernet connection. What's a good (cheap) hardware route to connect all this up? Am I right in thinking I'm going to need a router? Will the router need to have the QOS voice priority implemented? Does VM know or care what kind of router sits behind the modem? Is a modem/router a possibility? Any input greatly appreciated.

[Aragorn]

If you will never need wireless you could get a Linksys BEFSR41, which is a 4 port cable router, at around £30. For only another £4/5 you could get a WRT54GS wireless router for future proofing. Other cheaper makes are available but I've always used Linksys myself.
Note - anything you buy must be a 'Cable/DSL' or 'Broadband' router - ADSL modem/routers will NOT work on VM.
Unless you are doing heavy downloads on the PC, eg filesharing, then you are unlikely to need QOS. VM normally has no interest in what network devices sit behind the modem.
HTH (& )

[ceedee]

Yes, you'll need a router.
There are hundreds of models available but make sure you get one that's for cable (ethernet) rather than ADSL (RJ11) such as those listed here on BroadbandStuff.
For £40 even VM will supply (and more importantly, offer support for) a decent Netgear wireless router.

In my experience of using a similar setup, QOS isn't necessary but should help improve the quality of calls while you are downloading on your pc.

There are combined cable modem/routers but they are not supplied or supported by VM.

Oh and don't worry about asking what seems like 'dummy' questions: we all have to start learning from somewhere! And every 'expert' here, was a n00b at some point.

hth

[labougie]

Brilliant, thanks guys.

[PtolemyIV]

I've just joined virgin and am trying to hook up my wrt54gs to the cable modem to relay internet access wirelessly around my flat.

i want to use the wrt54gs as the dhcp server for my local lan (192.168.1.x)

however i am finding that: (all being tested using wired ethernet to router)

a) if i connect pc to router with no modem connected then router assigns appropriate ip in range (e.g. 192.168.1.100). however, if i then connect the cable modem to the router i am unable to browse internet.

b) if i have modem connected to router and then connect pc to router then i get assigned a global ip address (e.g. 92.234.x.x) presumably by the cable modem. i can access internet but only one device connected to the router can access internet at once (only one valid ip gets assigned and no more devices are able to join network) - also can obviously not have my internal lan for connecting various devices together.

I have tried following the approach of:
1. turning off cable modem, router, and pc for 2+ mins
2. turning on cable modem and waiting 2 mins
3. connecting router to cable modem and turning on and waiting 2 mins
4. connecting pc to router and turning on pc

PC still gets assigned a global ip address!

It seems to me that i want to turn off the dhcp server in the cable modem but accessing the router page (192.168.100.0) yields no options to do this (status pages only)

Any suggestions on how I get my desired setup working?

Thanks for your help!

[Steve-o||[^]]

Originally Posted by PtolemyIV

a) if i connect pc to router with no modem connected then router assigns appropriate ip in range (e.g. 192.168.1.100). however, if i then connect the cable modem to the router i am unable to browse internet.

Are you able to ping, say..the BBC?
Are you using appropriate DNS servers? either using NTL/VM/OpenDNS/etc 'hardcoded' to the PC(s)..or by using the routers DNS relay to forward to NTL/VM/OpenDNS/etc DNS?

Originally Posted by PtolemyIV

b) if i have modem connected to router and then connect pc to router then i get assigned a global ip address (e.g. 92.234.x.x) presumably by the cable modem. i can access internet but only one device connected to the router can access internet at once (only one valid ip gets assigned and no more devices are able to join network) - also can obviously not have my internal lan for connecting various devices together.

Interesting...is that IP on the PC or the WAN interface of the router?

Originally Posted by PtolemyIV

It seems to me that i want to turn off the dhcp server in the cable modem but accessing the router page (192.168.100.0) yields no options to do this (status pages only)

the external IP is assigned to the MAC address of the modem by DHCP - this cannot be turned off AFAIK. Also, from your example, the default router IP should be 192.168.1.1, and the cable modem should be 192.168.100.1.

[PtolemyIV]

Originally Posted by Steve-o||[^]

Are you able to ping, say..the BBC?
Are you using appropriate DNS servers? either using NTL/VM/OpenDNS/etc 'hardcoded' to the PC(s)..or by using the routers DNS relay to forward to NTL/VM/OpenDNS/etc DNS?



Interesting...is that IP on the PC or the WAN interface of the router?



the external IP is assigned to the MAC address of the modem by DHCP - this cannot be turned off AFAIK. Also, from your example, the default router IP should be 192.168.1.1, and the cable modem should be 192.168.100.1.

No ping. Have not manually set DNS servers on PC. Don't really want to have to set these manually on each device that accesses the wireless network!


The 'global' IP (92.x.x.x) is the IP that gets assigned on the PC.


Yes, 192.168.1.1 was the router IP and cable modem 192.168.100.1

Should I change them to be on the same subnet mask -> i.e. make the router ip e.g. 192.168.100.2 - is that sensible or irrelevant?


Appreciate the help.. oddly I previously had an old ntl cable modem at a previous address and had no such issues connecting this same router

[whydoIneedatech]

Originally Posted by PtolemyIV

b) if i have modem connected to router and then connect pc to router then i get assigned a global ip address (e.g. 92.234.x.x) presumably by the cable modem. i can access internet but only one device connected to the router can access internet at once (only one valid ip gets assigned and no more devices are able to join network) - also can obviously not have my internal lan for connecting various devices together.

Thanks for your help![/quote]

================================================== ======

What you call a Global IP address is the Virginmedia IP address your modem has requested from Virginmedia servers.

To receive an IP address you must have your modem switched on and connected to the PC either directly through an Ethernet cable or through a router.

You cannot access the Internet unless you have the IP address 92.*.*.* or any other Virginmedia IPs otherwise all you will have is an internal network without any Internet access.

[Vorthal]

An important consideration to take into account when purchasing a router is it's data routing speed.

I had been using a Linksys BEFSX41 for about a year on 10Mb with no problems. When my service was upgraded to 20Mb.. I could only receive 11Mb when using the router.. but 20Mb when the modem was plugged directly into the PC. The router couldn't process the data fast enough. So because of this, and because I'd already had 2 free upgrades from VM.. so more were possible in the future, I got a D-Link DGL-4300.. which is known to be one of the "fastest" routers.

This website illustrates the speeds of various popular routers: http://www.smallnetbuilder.com/compo...er/Itemid,156/

Note: Unfortunately, this site is currently down for maintenance, however you may be able to access it using Google cache here: http://64.233.183.104/search?q=cache...lnk&cd=1&gl=uk

Hope you find that useful.
Vorthal

[Aragorn]

Stoopid question here - is the enet cable from the modem plugged into the WAN (aka Internet) port on the WRT54GS? It has 4 local rj45 ports with the WAN port separate.
Your symptoms match what you would get if the PC and modem were both plugged into the local rj45 ports.
Otherwise, strange.
BTW - no need to change the default router or CM IP addresses.

[Steve-o||[^]]

Originally Posted by whydoIneedatech

To receive an IP address you must have your modem switched on and connected to the PC either directly through an Ethernet cable or through a router.

You cannot access the Internet unless you have the IP address 92.*.*.* or any other Virginmedia IPs otherwise all you will have is an internal network without any Internet access.

Not really. You could have a router sitting there with no other devices connected to it and VM would still issue you an IP*.


It's ok to have an internal IP on the PC/other devices connected (wired or wireless)....so long as a) your router has a VM IP b) has a default gateway and c) has a routing entry telling it "anything not on the local subnet should be routed out the WAN interface to the default gateway.". A and B are taken care of by VM and C is taken care of by the router.



+1 for the DGL-4300 all we need now is updated firmware with SNMP support!


* so long as the modem's MAC is registered to an account with a valid service subscription, and there's no other problems on the network.

[whydoIneedatech]

Originally Posted by Steve-o||[^]

Not really. You could have a router sitting there with no other devices connected to it and VM would still issue you an IP*.


It's ok to have an internal IP on the PC/other devices connected (wired or wireless)....so long as a) your router has a VM IP b) has a default gateway and c) has a routing entry telling it "anything not on the local subnet should be routed out the WAN interface to the default gateway.". A and B are taken care of by VM and C is taken care of by the router.



+1 for the DGL-4300


* so long as the modem's MAC is registered to an account with a valid service subscription, and there's no other problems on the network.

In the above case yes he needs a PC to be connected as he wants the Internet, read what he said about his home network, he thinks he can get onto the Internet without as he puts it a Global IP Address, in other words a Valid Virginmedia IP address.

But yes you can just connect an XBOX, PS3 or a Wii and get an IP and play online, a router will receive an IP but no one can use it unless they have a wireless device that can connect to the router in order to utilise that IP address.

[Vorthal]

Originally Posted by Steve-o||[^]

+1 for the DGL-4300 all we need now is updated firmware with SNMP support!

Exactly! The latest used to be 1.8, but that was pulled. I'm running 1.7 now.. which is like 2 years old. I think D-Link must have forgotten about us

[PtolemyIV]

Originally Posted by whydoIneedatech

In the above case yes he needs a PC to be connected as he wants the Internet, read what he said about his home network, he thinks he can get onto the Internet without as he puts it a Global IP Address, in other words a Valid Virginmedia IP address.

But yes you can just connect an XBOX, PS3 or a Wii and get an IP and play online, a router will receive an IP but no one can use it unless they have a wireless device that can connect to the router in order to utilise that IP address.

That's not what I'm saying - I know that the router needs to get assigned a virgin media ip.

The problem I am finding is that the only way I can use the internet via pc->router->cable modem is when the pc itself somehow gets assigned the VM IP. (despite router set to act as dhcp server)

If I do the standard practice of turning off all 3 devices, and connecting 1-by-1 so that the PC gets assigned a local IP by the router, then I am unable to access the internet on the PC. How can I check on the router (using DD-WRT) if it has successfully been assigned a VM IP?

Do I need to manually configure the DNS relay or such on DD-WRT? I have tried putting 192.168.100.1 (modem ip) as default gateway + local dns but to no avail.. (if I reset router they default to 0.0.0.0)

Thanks for any further help..

[Joxer]

It would appear that your router is behaving much like the old telewest wireless access points do - i.e. merely forwarding the ip it is given and thus allowing only one device to connect to it. It is not acting as a dhcp server in it's own right. Can you access the router config pages? I think you want to have a look there and probably make some changes. If everything looks ok there, try hitting it with a hammer. Or maybe see if it has a reset button on the back and configure it again from scratch, the settings it's showing you are not necesarily the ones it is using (probably safer than the hammer option but less fun).