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Why Are T1 Lines Still Expensive?
badfrog asks: "Over the last 10 years, DSL and cable modem has upped its speed (although in some instances only slightly) and dropped its price. However, the price of a T1 has stayed almost exactly the same. If you had asked me 10 years ago, I would have predicted any geek that wanted to would have fiber or their own T1 line to the house by now. What is with this sad state of affairs that a 'business class' 1.544Mbit connection is hundreds of dollars more than a 6Mbit cable connection? Is it a legitimate case that a high upload rate should increase cost so significantly?"
They're so expensive because there's not alot of competition for them, and if you need it, you cant live without it.
You dont have the option of moving to a Cable connection, or even several, because of the need for so much upload. You're stuck. And there's no incentive to lower prices.
You don't oversubscribe the T1, but you can oversubscribe uplink on the router that all the T1's traffic goes through to get to the world (the ISP's OC12, whatever).
I've seen it done, and would not be surprised at all if the majority of tier 1's do it. It's a huge waste of money to assume that all your customers will use all their bandwidth all the time.
The only added service a T1 buys you is a more sympathetic ear when problems crop up.
You're paying for the guy on the phone, when the circuit goes down, to say "yessir, it'll be up in less than 10 minutes". And mean it.
Why is it that many people who claim to support standards have such atrocious spelling and grammar?
The parent is correct. You seem to be the one a little out of it. And snidey at that.
T1s are point-to-point circuit switched connections. The Internet only factors in if one device on that point-to-point connection happens to be a gateway router.
Being point to point, it's isolated, secured, easier to secure, and probably guaranteed via some policy or contract. You don't share with no one.
DSL has a same setup; you don't share your connection like cable internet. However, with DSL, you only have a closed circuit between you and an isp. To reach your office across the state, the connection has to traverse your ISP's routers and distribution systems then to your office's. Do a traceroute one day.
With a T1, the closed circuit is between you and your office cross-state. Your ISP only uses layer 2 switching to make sure the circuit takes the optimal path. Once it's connected, it's locked in. And unlike internet via DSL or cable with your ISP in the mix, TCP/IP doesn't have to factor in at all if you don't want it to. You get your choice of protocols for addressing and transport.
You seem to think because since you saw some guy hooking up what looked like a phone jack to your buddy's computer that you're en expert in the field and have the right to be a pretentious dick about it. Sorry to disappoint you.
In this case, the medium is not quite as important. The cabling is nothing much more then a polished POTS line. However, you still have the other 6 layers of the OSI model to think about.
But you do most certainly oversubscribe the connection onwards from wherever the lines (be they t1 or adsl) terminate.
Put differently, if you've got 10.000 subscribers for 1Mbps ADSL, you most certainly don't hook these into the Internet using a 10Gbit link. If you did, you'd be having 95% overcapacity on average, and probably 80% overcapacity at the peaks. (i.e. you'd literally *never* use more than 20% of your bandwith)
Same applies if your customers come in over T1-lines.
Now, there's still differences. Typical el-cheapo consumer-isps tend to simply accept that their lines spike for 10% or more of the time. In other words, if their actual load is 100Mbps average, 500Mbps peak, they'll buy perhaps 200Mbps, and simply accept that nobody gets more than half their rated speed if surfing at peak times.
ISPs with a higher service-level try to keep their capacity around peak. Which means that if they calculated correctly, you'll "always" get your rated speed. You *may* on occasion experience sligthly less if they miscalculated.
Insane ISPs, like Uninett has a target bandwith of 150% of the highest experienced former peak. In other words, aslong as *now* doesn't have 1.5 times the highest load experienced in the past, you'll get your rated speed. Notice that this too is probably an order of magnitude less bandwith than you'd need if you did not overprovision.
Not overprovitioning is a lot like building roads as if everyone who owns a car would be driving it 24/7/365. If you did, you'd be spending 10 times the money on roads from whats really required.