One of my buddies called me up today to help me hook up his new machine to a AT&T/SBC DSL modem. His old machine was connecting to the internet with some Yahoo ! DSL software, and was connected directly to a Speedstream DSL modem via ethernet.
OK, so the new machine, when directly connected to the DSL, would not recognize the DSL. When I plugged my MacBook Pro into the ethernet, it would not connect either. I would ping, and I’d get the message “No route to host.” After scratching my head for a bit, I decided to hook up a Linksys wireless router into the network. In other words, the DSL connection ran into the router, and the router outputs would run into the computers.
This worked. Both wireless and ethernet connections were able to access the internet. I went on to delete all the stupid SBC/Yahoo/AT&T connection crap on his old computer, and just double-clicking on Internet Explorer would connect to the internet–which is exactly the way I’m used to it working.
So, while I’m happy it all works, I want to know what’s going on here. Why can’t I connect the Speedstream DSL modem directly to my computer and get a connection? Why does it work through the old computer with some kind of SBC DSL software installed? Why does connecting it through the router solve all of these problems? At my girlfriend’s place, she’s got AT&T DSL, although her comes with some sort of modem that doubles as a wireless router, and I can connect directly to it through the ethnet cable.
Obviously, I’m missing some crucial bit of knowledge about networking here. Anybody help me out?
Usually with a direct modem connection you need to connect to the ISP’s network by accessing the modem’s IP (usually 192.168.0.1 for speedstreams). In order to gain entry here you have to enter the modem access code printed on a sticker on the bottom of the modem. You would also have to enter the username and password into the modem’s connection page to complete this.
With a router attached, none of this is necessary (except perhaps the login information). For what reason I do not know, but I have had SBC DSL for about 7 years and it’s always been this way.
Without knowing the exact model number of the Speedstream DSL modem you’re using, I’m going to deduce from your observations that it doesn’t have a user interface webpage (accessed via http://192.168.0.1 or similar) that you can use to load the modem with your friend’s Username and Password. Instead, these parameters have to be provided by the device immediately "downstream"of the modem, each time the latter tries to start a connection to the Internet.
In the past, your friend had the (IMHO) crappy Yahoo/SBC/AT&T software loaded on his PC, into which he had entered the username and password when he first installed it. Boot up PC, launch an Internet connection, and the old PC sent the username/password to the modem and through to SBC, establishing a connection.
Now, when he tries to connect his new PC directly to the modem, it doesn’t have the username/password to pass to the modem (no Yahoo, etc. software loaded) so no connection results. Same with your MacBook. BUT, when you put the router downstream of the modem and went to the setup webpage (192.168.0.1 or whatever), you entered the username & password into the correct fields and the router stored it in non-volatile memory. Now, any PC can connect to the router without needing to know your friend’s DSL username and password. Of course, if he’s smart he’s enabled WPA encryption on the wireless link, so your MacBook does have to know the WPA password.
Your girlfriend’s modem is more up-to-date and “smarter” than your buddy’s, and not only has the router function but also her DSL username and password stored in non-volatile memory. She fed them in when she set up the modem / router via 192.168.0.1 or whatever (varies between brands and models).
So now, none of the computers involved need to have the DSL username / password, because they’re stored in the router (buddy) and modem/router (girlfriend). Result: no crappy Yahoo / SCS / AT&T malware, everybody happy. Yes?
Yeah, I tried 192.168.1.1 and 10.0.0.1, but didn’t think to try 192.168.0.1 (I wasn’t familiar with that particular address, since I’ve never really worked with modems directly, but always through a router).
Gotcha. So everyone’s saying the login info was stored on the router, so that’s why it worked?
Anyhow, I deleted all that Yahoo/AT&T/DSL crap off his computer (plus all sorts of malware), and everything appears to be hunky dory.