Why won't my wife's computer connect to the internet?

Factual Questions
1

My wife and I are in the process of moving. We hired Mediacom to install high speed internet. When the guy came to install it, I handed him my computer (a Macintosh) and he configured the system and was on his way. Later, I tried to set up a wireless network with my new DIR-615 wireless router. I had no problem connecting my computer to the router, but the router wouldn’t admit that an internet connection existed. I spent several hours on the phone trying to sort it out to no avail.

Then my wife decided she wanted to connect one of her PC’s to the internet. Since we hadn’t gotten the wireless connection set up yet, we just connected it to the modem with an ethernet cable. Neither of her PC’s will connect to the internet this way. I just plug my Mac in and I’m fine. Both of her laptops say that they are connected, but when you try to open a web page it says the server can’t be found. She has no problems connecting her PC to other networks with an ethernet cable.

This is really frustrating, because when I called Mediacom to tell them there was a problem they insisted that the problem was mine. As long as one My Macintosh can connect to the internet, the network is fine the problem must be the three things that cannot connect to it, despite the fact that both of my wife’s PC’s can connect to the ethernet at school without a problem.

2

When in doubt, power everything off and then back on.
My IP uses a satellite. The satellite modem worked great on the PC, but wouldn’t talk to a router. Powering the modem off, and back on to “see” a new piece of equipment, the router, caused all to work well.

3

If the mac connects, the tech support folks are probably right. For starters, what version of windows is on the PC? All should connect, but advice to you will be version specific…I can’t help much with Vista fer example, as I know just enough to know that nothing is where I am used to finding it in XP. Also, when Wifey connects at work, is that via a wired or a wireless connection?

4

I think that some cable modems associate themselves with only one MAC address. So you may need to power-cycle it to clear the association. Or you can configure the router to spoof the MAC address of the Macintosh.

5

[QUOTE=Dewey Finn]
I think that some cable modems associate themselves with only one MAC address.
[/QUOTE]

That is true of the satellite modem I described above.

6

I did the power off, power on thing. It will be a while before I can get back to the connection to try it again. One of my wife’s computers is Windows XP, I don’t know about her newer one.

7

Hey, I just wanted to tell people my ultimate solution in case someone can explain it to me. I understand now that you can’t just switch computers at the modem. Apparently it has something to do with the MAC address or whatever. (Explanaition of what the MAC address is, is welcome.) We were always told by Mediacom that once we got a router the problem would go away.

We bought a wireless router. We tried everything. We powered down the modem, we plugged the router in then powered up the mkodem, then powered up the router. We downloaded the upgrades. We followed the instructions explicitly. We returned the router and bought another one. We followed the installation instructions explicitly. Everytime it got to the point where it was going to establish the connection it would hang there until twenty minutes later it would say “We could not establish an internet connection, are you sure you are connected properly?”. Of course we were connected properly so there was nothing to do.

Then, this weekend my wife and I went to a garage sale. They were selling this old junky wireless router for ten bucks, so we figured “What the hell?”. We plugged it in and instantly it was working. It is working exactly as we expected.

Here is my theory. Mediacom gave us a seriously outdated, ghetto modem. It really looks old. I was talking with the guy at Bestbuy about it and he said it sounded nothing like the modem he got. This thing is giant as far as modems go. Its definitely not new. New routers just couldn’t deal with it for some reason. That is why when we bought the old router it connected perfectly.

Thoughts?

8

[QUOTE=Christopher]
Hey, I just wanted to tell people my ultimate solution in case someone can explain it to me. I understand now that you can’t just switch computers at the modem. Apparently it has something to do with the MAC address or whatever. (Explanaition of what the MAC address is, is welcome.) We were always told by Mediacom that once we got a router the problem would go away.

We bought a wireless router. We tried everything. We powered down the modem, we plugged the router in then powered up the mkodem, then powered up the router. We downloaded the upgrades. We followed the instructions explicitly. We returned the router and bought another one. We followed the installation instructions explicitly. Everytime it got to the point where it was going to establish the connection it would hang there until twenty minutes later it would say “We could not establish an internet connection, are you sure you are connected properly?”. Of course we were connected properly so there was nothing to do.

Then, this weekend my wife and I went to a garage sale. They were selling this old junky wireless router for ten bucks, so we figured “What the hell?”. We plugged it in and instantly it was working. It is working exactly as we expected.

Here is my theory. Mediacom gave us a seriously outdated, ghetto modem. It really looks old. I was talking with the guy at Bestbuy about it and he said it sounded nothing like the modem he got. This thing is giant as far as modems go. Its definitely not new. New routers just couldn’t deal with it for some reason. That is why when we bought the old router it connected perfectly.

Thoughts?
[/QUOTE]

Simplistic version.

Connect one machine to modem.
Once working, D/C from modem, shut off modem, setup router with only that one machine.
key point, look for “clone MAC address” making sure you clone the mac address from the machine that was working. Apply settings.

Turn on modem.

Modem should now see the COMPUTER’s mac address not the routers default one.

If you leave the modem on, this will not work…how do I know this…

Dozens of time doing it over because I left the modem on…

9

[QUOTE=Christopher]
This is really frustrating, because when I called Mediacom to tell them there was a problem they insisted that the problem was mine. As long as one My Macintosh can connect to the internet, the network is fine the problem must be the three things that cannot connect to it, despite the fact that both of my wife’s PC’s can connect to the ethernet at school without a problem.
[/QUOTE]

They are correct, you have added additional hardware between them and your machine. Just because they do not charge for support calls does not mean they have to support other things you do.

10

I know that they are technically correct. If they want to legal their way out of providing me with the service I wanted they win. Whether or not I’m going to continue to pay them for a service that is not working properly is my choice. If I can’t get a router to succesfully hook up to my modem, I’m not interested in that service. I frankly don’t know of anyone that wants an internet service that is incompatible with a network. Until I picked up this piece of junk router that worked, I was going to tell Mediacom to shove their service up their asses. Seeing as I’m likely to be interested in a high speed network for most of my life that would have represented several thousand dollars of buisiness to them.

11

[QUOTE=Christopher]
I spent several hours on the phone trying to sort it out to no avail.

As long as one My Macintosh can connect to the internet, the network is fine the problem must be the three things that cannot connect to it, despite the fact that both of my wife’s PC’s can connect to the ethernet at school without a problem.
[/QUOTE]

I sympathize, but I tend to agree with your provider. I suppose they could provide tech support for every type of network configuration you decide to put on the end of your internet cable, but then you’d be paying 3-4 times as much for service. Even then, they’d have plenty of pissed-off customers.

Setting up a home network is not easy, even for me. Modern networking has some design flaws, to be sure, but it was not ever designed to be simple to operate. I could not even fully explain why here, but trust me, it’s complicated.

I venture to guess that your provider offers an option where you can lease or buy the modem and router from them, and they’ll set the whole thing up. Unless you’re a tech guru or have access to one, that’s the way you should go. Saves you time, money, and anxiety. This advice holds for everyone in SDMB-land, too.

A MAC address is the physical hard-wired address of a piece of networking hardware. Most often, the term is used in connection with a card or chip in your computer. MAC addresses are absolutely unique; no two pieces of hardware are allowed to have the same one. Manufacturers have to request a block of addresses and then dole them out.

It would take a whole book to explain everything, as I said. Just know that a MAC address is unique and permanent (except in very rare cases).

I don’t know what happened with your original setup, but probably your provider couldn’t establish a connection from its hardware to your router. Being able to communicate between your home computers proves nothing; your computers should be able to do that even if you disconnect the router from the internet cable. The key is going “outside”; to do that, you have to establish a route from your local network (LAN) to the internet itself.

Why you couldn’t do this with the original setup, and you can with the new one? Impossible to tell without looking at it.

12

[QUOTE=Christopher]
I know that they are technically correct. If they want to legal their way out of providing me with the service I wanted they win. Whether or not I’m going to continue to pay them for a service that is not working properly is my choice. If I can’t get a router to succesfully hook up to my modem, I’m not interested in that service. I frankly don’t know of anyone that wants an internet service that is incompatible with a network. Until I picked up this piece of junk router that worked, I was going to tell Mediacom to shove their service up their asses. Seeing as I’m likely to be interested in a high speed network for most of my life that would have represented several thousand dollars of buisiness to them.
[/QUOTE]

The problem is far more likely to be your router confguration than a problem with the ISP. I have seen people do the same thing, get pissed, switch providers, same proble, switch routers, same problem, because they were not setting up correctly.

A decent onsite tech can have this up and running inside an hour, I do it all the time. Might cost you $60-$80 but it beats the hell out of all the frustration and switching ISP’s

13

All I know, is I plugged this old POS router that I bought at a garage sale in, and it worked like a charm. I spent hours on the phone with technicians for two different brand new routers and got nowhere.

The only conclusion I can come to, is that the outdated modem Mediacom gave me is not compatible with new routers.

14

[QUOTE=Christopher]
The only conclusion I can come to, is that the outdated modem Mediacom gave me is not compatible with new routers.
[/QUOTE]

That seems odd.

15

I don’t know enough about it to think its odd. What I do know, is that if everytime this happened to a new customer, Mediacom blows it off as if it is the customers networking ignorance, they will continue redistributing outdated modems without realizing the problem is theirs.

16

[QUOTE=Christopher]
Mediacom blows it off as if it is the customers networking ignorance,
[/QUOTE]
We do tend to do that. :slight_smile:

17

[QUOTE=Christopher]
I don’t know enough about it to think its odd. What I do know, is that if everytime this happened to a new customer, Mediacom blows it off as if it is the customers networking ignorance, they will continue redistributing outdated modems without realizing the problem is theirs.
[/QUOTE]

[ignorance fighting helmet on]

Problem is you are basically saying the old modem does not speak things like TCP/IP, ethernet standards, http, etc.

The routers speak “older modem” fluently even if the old modem does not speak TCP/IPv6. I can plug machines running win95 into a new router and have them run just fine even with a 12+ year old operating system and ethernet cards.

You don’t know enough to know what you say sounds weird but you know more than enough to say its the ISP’s fault.

Read below carefully.

You

Are

Wrong

You are playing in a world where one misstep can disable a router for good barring a firmware reload or a $300/hr network engineer going hmmmm thats an odd configuration for a packet.

You have several extremely computer saavy dopers telling you the truth. I sometimes do dozens of these a month. We are not trying to jerk you around, we are trying to help you. If you want to rant about your ISP…go to the pit. If you want to ignore the assistance and reccomendations of probably 150 years of combined computer experience floating around GQ do so at your own peril.

[/ignorance fighting helmet off]

18

Wow, when I want to give a really patronizing response I will be sure to use that “ignorance fighting helmet” thing.

No matter, all I know is that the new routers I purchased could not hook up to the modem. I stumped several of the technicians. I bought an old router at a garage sale. When I plug in the old router, it hooks up immediately.

Until you can come up with an alternative explanaition,
I

am

right

:wink:

19

[QUOTE=Christopher]
Wow, when I want to give a really patronizing response I will be sure to use that “ignorance fighting helmet” thing.

No matter, all I know is that the new routers I purchased could not hook up to the modem. I stumped several of the technicians. I bought an old router at a garage sale. When I plug in the old router, it hooks up immediately.

Until you can come up with an alternative explanaition,
I

am

right

:wink:
[/QUOTE]

Maybe.
With the new routers did you get on the horn with the tech guys from the router company or the tech guys from the ISP? It matters. You should have been able to contact the service dept for the routers for free to get them set up. This may have been your mistake and the router tech could have helped you right off the bat rather than all the dicking around you did.

20

[QUOTE=Christopher]
Hey, I just wanted to tell people my ultimate solution in case someone can explain it to me. I understand now that you can’t just switch computers at the modem. Apparently it has something to do with the MAC address or whatever. (Explanaition of what the MAC address is, is welcome.)

[…]

Here is my theory. Mediacom gave us a seriously outdated, ghetto modem. It really looks old. I was talking with the guy at Bestbuy about it and he said it sounded nothing like the modem he got. This thing is giant as far as modems go. Its definitely not new. New routers just couldn’t deal with it for some reason. That is why when we bought the old router it connected perfectly.
Thoughts?
[/QUOTE]

A MAC address is a device-unique serial number that tells other network hardware what kind of hardware they’re communicating with. Every piece of network hardware has a unique MAC address: every network card or router has its own, so if you have a PC with a wireless card and an ethernet jack, your machine might have two MAC addresses. It consists of six groups of two hexadecimal digits (hexadecimal is base 16, so a “digit” can be anything from 0 to 9 or a to f). The first three pairs tell you the manufacturer (and potentially the model year or type of hardware) and the last three pairs are a unique serial number.

It’s possible that your older router automatically broadcasts (or “clones”) the MAC address of whatever machines are attached to it (instead of its own) and therefore the cable modem is willing to play nice with it. In this scenario the cable modem would be fooled into thinking that the router was actually one of your computers, and your network would be invisible to the cable modem.

It’s also possible that if Mediacom is a monopoly in your area, and they maintain a list of “valid” MAC addresses, that the router you bought used has a MAC address that a previous customer used with Mediacom. In this case, the cable modem has been instructed not to give IP addresses to your new router (it’s not on the list) but your old router is a long-lost friend to any hardware on the Mediacom network, and can have an IP address just by asking nicely.

New routers are more strict about this: they tend to transmit their own MAC address until explicitly ordered to do otherwise. Your cable modem is refusing to talk to them because they’re being honest about who they are. If you haven’t looked up your Macintosh’s MAC address and told your (new) router to emulate/clone/transmit that same code, then you haven’t exhausted the possibilities.

Try this:

(1) Connect your Macintosh directly to the cable modem and find out what IP address gets assigned to it.

(2) Connect a PC to the newer (non-functional) router, and connect that router to the cable modem. Open a browser window on the PC, type in the address for the router’s configuration page (probably 192.168.1.1) and go to the status tab. If you think the info displayed there is wrong click “renew” or “refresh”. Write down the IP address and MAC address shown. The IP address should be a garbage string - either all zeros or one of the reserved “broken” addresses.

(3) If the MAC address shown in the router maintenance begins with one of these strings then your router is still telling the world that it’s a router and You // were // wrong. If the MAC address starts with one of these, then you might be right.

(4) Plug in your old router, connect a Mac or PC to it, and go to its remote maintenance page, if it has one. See what MAC address it’s transmitting. Please let us know what it says – I’m curious about what MAC address it could broadcast that the cable modem would accept. My theory is that the MAC address will not be from the cable modem manufacturer, but rather from a third-party NIC.