I thought only cable modem speeds went down as more people signed on.
Herc, the issue might be on the back end. If you had an analog (eg., 28.8) modem before, you probably noticed that sometimes your response time was better than others. That was because within the CO, and beyond it, lines are provisioned statistically--there are more "lines" coming in from customers than going out the back to the network.
Essentially, this situation is unchanged with dsl implementations. The telco can't economically supply all the equipment it would need to satisfy all users if they were all on at the same time demanding full bandwidth downloads. But, everyone is never on at the same time, and when on everyone isn't downloading simultaneously. But, if the equipment is near capacity, the customer can experience service slowdowns.
The situation is a little different from cable modems. Both have "statistical" chokepoints. But, the telcos' being in the CO means that they have more lines over which to reach a reliably predictable level of service. With cable, if you've got several really hungry users as close neighbors, I understand, you are quickly limited by their activity. With the dsl installation, usage and the bottleneck are spread out over more users. Thus the bottleneck will be more predictable, and the telco can upgrade more easily to ease the bottleneck problem, by providing additional equipment and/or line capacity at the CO.
That being said, if the drop in throughput was sudden, there may be one or more other issues: has the telco deliberately slowed down your connection? They can do this in some installations, I believe, and would do so to keep you in the correct price/performance profile or for some other reason. Is there a problem with the line? The telco can run a line check, I believe. (A line check should verify the quality of the line, not just that dsl is available, by the way.)
Corrections, comments by my more technically astute colleagues would be welcome.
Best,
JS |
