At first it looked like a screw-up on Roadrunner's part, which was easily fixed
Plugging a laptop directly into the cable modem (we have Roadrunner) verified that the the wireless access point wasn't the point of failure. Steve's laptop, plugged in directly into the cable modem (bypassing the wireless access point), was unable to get an IP address. So the problem was lack of service from Roadrunner. Steve's call to Roadrunner's tech support revealed that Roadrunner messed up switching our account from the old apartment to the new house. Interestingly, this happened a week after the move. At the beginning, they turned on the service at the house on the day of the move, and it worked with no problems. Then a week later they decided to finally cut the service off at the old apartment, and accidentally disabled both. Well, anyway: a short phone call later Roadrunner got it fixed. Their tech support had Steve plug his laptop into the cable modem again, and verified that the laptop was getting an IP address and was able to access the internet. So Roadrunner considered its end of the problem solved.
But the story didn't end here
But the story didn't end there. As we found out a few minutes after Steve hung up with Roadrunner, for all intents and purposes we still didn't have internet access. Despite the cable modem now working, the wireless router wasn't getting an IP address. Various rebootings and resettings didn't help. And we could not call Roadrunner back and ask for more help. Here's why. As I understand it, the type of service we signed up for with Roadrunner has a funny loophole. The contract does not allow more than one computer to use Roadrunner. If we wanted to use multiple computers, we would have to sign up for a more expensive type of service. And if you have a wireless access point at home, it's obvious that you are connecting multiple computers to it. Though in theory, even if you had only one computer, you might still want to have WiFi, so that you could to carry the computer around the house. So I guess Roadrunner can't automatically claim you are violating the contract if you have a wireless router... but still. So there is what I would describe as an uneasy truce between one-computer subscribers and Roadrunner. Roadrunner ignores it if a one-computer subscriber has a wireless router, but they tell you they won't help you administrate your router. That's your responsibility.
Who to call, then, if your router still doesn't work after Roadrunner fixed the problem? (And, I repeat, the wireless part was working well: it was emitting a signal. It's just that it wasn't getting an IP address from Roadrunner. So it definitely had something to do with what RR did on their end -- it would have been too much coincidence if the router just started malfunctioning at the same time.) I suppose we could have called Linksys (the manufacturer of the router). But Steve had a better idea...
Next step: call Vonage
...let's call Vonage. For you see, we subscribe to an internet phone service from Vonage.
Actually, we don't use it. There's no logic in that. Steve got Vonage because it provides very cheap long distance phone calls. The problem is, neither of us makes long distance phone calls very often. It's not like we have no one to call: Steve's and my families live correspondingly halfway across the US and halfway across the world. And the result? Steve talks with his mom on his cell phone; whereas I, since my emigration 12 years ago, have talked with my family on the phone exactly twice. :-) Not because I am an ungrateful daughter and sibling (though I might be :-)) but because spoken word is soooo not my medium. I am a written word person. I like a medium where I can edit myself and present the other party with complete thoughts, instead of half-finished phrases. I like a medium that does not require me to rack my brain trying to come up with filling for "uncomfortable" pauses. So, long distance phone service to me is like a proverbial bicycle for a fish. :-) And there is a significant downside of having a phone service that uses your internet connection: when the internet is down, your phone is down. OTOH, a conventional land line would stay up when the internet is down. So if one needs a land line of any kind (which I don't -- a cell phone is enough for me), a conventional land line makes a lot more sense than an IP phone. So frankly, I don't know why Steve wants to keep Vonage service.
If you are paranoid about privacy, Vonage may not be for you
There is just one little detail about Vonage service that may raise the hackles of anyone who is paranoid about privacy; I on the other hand, believing my files may only hold interest as a fast remedy for insomnia, don't mind surrendering a little privacy for convenience. :-) When you subscribe to Vonage, Vonage "locks" your wireless router so that its tech support could administrate it. By "locking" the router I mean that Vonage has the password to the administrator's account. They still let you administrate it yourself (at least partially) by creating a different account for you. Regardless, you don't have a complete control over your router.
I'm not clear on details of this. Steve said that he bought our wireless router already pre-locked for Vonage! I don't know if all Linksys routers sold in the US are that way (doesn't seem likely to me) or if this one was one of a batch of pre-locked routers sold as part of a deal between Linksys and Vonage, where you could get a Vonage subscription cheap by buying a Linksys router.
How did Vonage tech support fix our router problem?
But when you are racking your brain over what's wrong with your router, it's handy to be able to call Vonage and say "your phone service isn't working" (omitting that we really just want to get on the internet, not to use their IP phone) and get them to fix it. And fix it they did -- they had to. The problem turned out to be interesting. To me, at least. Not technically, but politically.
The answer, suggested by Vonage tech support, was to change the MAC address of our wireless router to be the same as that of Steve's laptop. (I didn't know MAC addresses were changeable, but apparently they are.) Why? Because when Steve made his previous phone call to Roadrunner and had them fix the problem on their side, Roadrunner made it so that only Steve's laptop would be able to connect to their service. Remember, Steve had his laptop plugged into the cable modem during the phone call for the purposes of testing. Roadrunner recognizes his laptop by its MAC address.
So, in order to make the wireless router to connect to Roadrunner, the router now had to be given the same MAC address as Steve's laptop. Once Steve did that, it started to work.
Because they knew a secret Roadrunner kept from us
Of course, Roadrunner didn't tell Steve that they will limit our service to this particular MAC address. Steve had no way of knowing that. If not for Vonage, we would not have found out. And I don't know how Vonage's tech support knows those things: maybe from experience? Maybe they have to deal every day with customers whose service stopped working after they moved to a new house?
So the whole situation looks pretty weird to me. Roadrunner messes with your settings and they won't tell you what they changed. And you can't call them to find out, because hey -- they've done their job, and any problems you may have afterwards are your router problems, not Roadrunner's. Even though RR effectively disabled your router by keeping a key piece of information from you.
I don't know, maybe I misunderstood something, maybe there's more to this story. Steve wasn't most forthcoming with the details. He was in a grumbly mood after those two phone calls, and I don't blame him. Running a tech support gauntlet does that to you. So I didn't press him for details.