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Some Customers Can Roll Their Own DSL
Allnighterking writes: "SBC has announced self installed DSL for large sections of their coverage area according to this article at CNN.com. More information available here for your area. Seems that they believe the support is available only for win98 at the moment with Linux et al support coming later. However, it's been my experience that with a little bit of networking knowledge and the external modem you can make it work on *nix now. The claim is that you can install in under one hour with 24/7 support available."
I know I roll my own, but I don't call it DSL...
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heLlo... myy naame issh Linush Thoralvades, and I pronounsch (hic) it, "vodka"!
I have DSL form swbell. I'm mostly satisfied but i couldn't figure out why i wasn't getting an address form dhcp. People in neighboring towns that had dsl just used dhcp and went.
Well sbc now uses PPPoE (ppp over ethernet). I'm using rp-pppoe from Roaring Penguin. This is under Linux.
If you get the DIY Plus special, you get 3 miles of copper wire, a trench digger, and right of way from your place of residence to the CO.
This is my sig.
While that is a feature, there are some other nice advantages. If you want to have more then one type of service on a single circuit (say best-effor 100x over subscribed AOL account for one PC, and a mere 4x oversubscribed small-bisness account for another -- or even the same PC depending on what you are using it for) you can do it with PPPOE, while that is hard to impossable with DHCP.
You can do a lot more configuration at a higher level. Tracking an account number is much simpler then tracking a set of MAC addresses (which will change if the consumer gets a new computer, or ethernet card - and may move from point to point on your network anyway!). Tracking an account number tends to be somewhat simpler then tracking a (Router,Card,Curcit-ID) tuple, and it simplifyes moves as well.
It also disrupts a home network far less. You don't have to configure your network aware printer NOT to ask for a DHCP address (which would end up putting it on the global net, and possably using your only address!). If you have multiple computers allready on a network, and you want to put one on the Internet, this won't force you to get another card for it, or to sever it's connection with the existing network. This may be a rare case, but I assure you it was one the authors of the RFC did have in mind. Rember if your ISP does DHCP for you, it is a lot harder for you to also do DHCP for your local network!
If the ISP allready has a RADIUS infrastructure set up for a large dial network, this allows them to reuse it for DSL. This is a fairly big deal because beleve it or not it is a pain integrate yet another database (DHCP's configuration) with allready existing order, payment, accounting, and other random systems at the ISP. A PPPOE baised DSL set up will look a whole lot like the existing dial set up (presumably with a higher monthly fee).
Cable is well and good until either (A) everyone in the neigborhood gets it and nukes the bandwidth or (B) you want to run a web/name/other server and the company forbids it.
"You done taken a wrong turn."
-Bill McKinney, in Deliverance
Eh? I don't think this is why they run PPPoE. It's easy enough to set up DSL so that each user is bridged in and gets a single IP address. However, this approach has some security drawbacks. One is that it's hard to keep people from hooking up more than one computer, and grabbing more than one real IP address (or a whole ton of IP addresses.) It's also pretty hard to track down who did what when without PPPoE. If the evil hax0r kiddie changes his MAC address, steals an IP (instead of going thru the DHCP server), starts his DoS attack, and then puts his MAC back to normal and DHCP's an address, the ISP is going to have a hell of a time figuring out which user that traffic came from. They will have an IP address, but it was never assigned. If they happen to have an arp entry, they may have a MAC address. But, it's a MAC that isn't on the network anywhere. They could keep a log of every change in the bridging tables, but I'm not sure how realistic that is. Even then, and "smart" kiddie will change his MAC address to one used by a legit user, so when the ISP starts looking around they will track the traffic down to the wrong house.
On the other hand, getting an IP address from PPPoE requires you to login. So, any traffic from that address is provably from that user. All neat and tidy. Any reasonable PPP server will easily log each login session. Much easier from an ISP's point of view than dealing with the limitless ways a customer can screw with a plain old DSL line (or a cable modem. Most of the problems I mentioned apply to them both.)
Then they ship me the 'customer self-install kit' a few days before my appointment with the technician, which includes a DSL modem, ethernet card, crossover cable to connect the two, and a bunch of filter boxes that connect to the phones on the line with DSL to strip out the noise. I call up and ask if, since i've received the customer install kit, I can in fact do my own installation. No, I'm told, I'll have to have a technician install it, and there must have been some mistake in shipping me the kit.
The technician shows up this morning, and the only thing he does that I couldn't have done with a page of instructions was to plug a signal meter into the line with DSL on it and declare the quality sufficient. Then all he did was monkey around on my Windows machine installing the PPPoE software, signed on in the 'register new user' account, pulled up the online signup page, and let me type in my preferred username and password.
That signal meter reading apparently costs $99, because that's how much a technician install costs. Self-install is free.
So, my non-technical tip of the day: if you get DSL from Southwestern Bell, and they send you a self-install kit, self-install.
The technical tip for the day: PPPoE works just fine with SBC DSL. If you've got a development kernel, build it with 'packet socket' and 'PPP over ethernet' options enabled, and apply this patch to a recent version of pppd.
My /etc/ppp/options looks like this:
defaultroute /etc/ppp/pppoe.so
plugin
name mylogin
And my /etc/ppp/pap-secrets looks like this:
mylogin * mypass
To bring up the ppp link, i just type pppd eth0.
The only thing that is a bit different with today's dsl providers (and perhaps cable soon) is their use of PPPOE. (ppp over ethernet). The reason? They bring things out to the home at layer 2 (ethernet), rather than the more traditional layer 3, but want to really give you a layer 3 anyway. In other words, they don't wanna waste address space building infrastructure.
This is actually a good thing.. it's just a bit different.
Rolling my own may save a bit of time, but I'd be willing to wait even a month to get a better service elsewhere. Anyhow, that's my person take on it. Your mileage may vary.
I have Bell Atlantic (ugh) DSL, and they have these little "Self-install" kits they ship out. Takes w hopping 30 minutes to set up. Am I missing something here?
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Matt Singerman
Matt Singerman
http://matt.vegan.net/
If you're in my boat, and you get basic DSL from SBC thru your telco, you're goign to be using (as others have mentioned) PPPoE.
If youre using windows to control your router, this is probably an ok situation. however, there appears (at this time, anyway) to be a significant lack of quality PPPoE options for people running linux; people runnign openbsd (at least as of the time that I installed my DSL) are completely screwed.
the solution: the Cayman (www.cayman.com) 3220H. this little box is a very fullfeatured router that operates on its own - no need to have a computer control it, which means that you can reboot your gateway machine without losing your IP. all PPPoE negotiations are done by the router itself.
I have one of these; I don't work for or own any of Cayman, just thought I'd let you people knwo the option is available. usually your telco or sbc or whatever will charge you like another hundred bux or so for this box, but in my opinion, it's well worth it.
(note that you'll have to download the newest operating system image from the Cayman site and flash it onto your router in order for it to properly do PPPoE, but that took all of about 3 minutes to do.)