On that note…here is a smokeping for my DSL connection:

Anything I can do besides killing all of my neighbors? It’s obvious the horrendous latency problem only appears during the peak evening time frame.

heh… I just upgraded from the basic dsl service to the 3.0mb service. I was getting 1.2mb at most. Opened a trouble ticket. They had me remove the line filter to my modem and it bumped to 1.6mb. Since they advertise (in the small print) 1.5 to 3.0mb as part of this plan they closed the ticket and said in reality anyone on the 3.0mb plan would get 2.2mb at most.

Meh.. better than the 768kbps I had before.
The basic design of phone networks requires that there is a dedicated line all the way to whatever is the modern equivalent of the switchboard, and that the main line has enough bandwidth to carry ALL of the service lines at full quality.

Cable, on the other hand, is a multicast system, where the same content gets piped to everyone all at once, so there’s no need for dedicated bandwidth to each customer.

So yeah, you don’t have your own personal dedicated connection to every other computer on the internet, but there has to be enough bandwidth to carry all of those connections at full speed, or else they wouldn’t also be able to carry high-quality voice calls to/from all the customers either.
It is dedicated, but that doesn’t mean that your ISP can handle all of the traffic on its network. Looks like the network is being overloaded at peak time and its not necessarily your neighbours.

Tell your ISP to buy more bandwidth and upgrade its network … not likely to happen.
deusexaethera obviously doesn’t know what multicast means, because it certainly doesn’t apply here.

Also DSL oversells just the same as cable does. Due to the nature of DSL, however, load is split across an entire DSLAM as where cable is split up into nodes. Telcos can shuffle customers around to different DSLAMS with a simple twisted pair and a punch tool…. but cable cos cannot reasonable shuffle around nodes without laying down more fibre. It’s not uncommon for some cable nodes to be under-utilized and other nodes to be over-utilized… So some neighborhoods will experience good speeds and other neighborhoods may be starved for bandwidth at peak times.

In my area about a year ago, I was lucky to get 400Kbit/sec on cable (and I mean *LUCKY*)… but after re-doing their HFC I now get 8MBit/sec during peaks and 13MBit/sec off-peak (I pay for 16Mbit/sec service).

DSL, on the other hand, has proven to be extremely *consistent* for me. Not quite as fast as what cable currently offers me, but I still do have a Qwest DSL line as a backup, and it is very reliable.

Overall, EVERY residential ISP is going to be over-sold. If they’re not, then the company will not be profitable, and will go under. That being said, when designed properly, it works 99% of the time.

I had the same issue with DSL in two different regions, where I consistently received the lowest guaranteed speed in the contract. Pays to read the fine print. I’ve been with cable for three years now and consistently have the max advertised speed. I’m afraid to move.

Note the little diagrams on the right side of the page. I think I hit it spot-on. Content is broadcast to neighborhood hubs, and then it’s multicast to subscribing customers.

Semantics aside, the point is that cable didn’t have to have enough bandwidth on main lines to supply full bandwidth to all service lines at all times, because back when it was only used for TV, most of the content was redundant from house to house, whereas phone service has always required full bandwidth to each customer. So DSL is still the better deal, on account of the underlying technology.

not really, multicast isnt a topology but the idea of sending the same data to multiple ends at the same time… if they were multicasted and 5 customers were watching the same streaming webcast it would only pipe it once and everyone would pick it up

IBYouDidntUseTheRightTerms
Broadcast and multicast both transmit data a single time and then it gets replicated at each hub where there are multiple recipients, but broadcast is received by everyone in range, whereas multicast is received only by those people who want to receive it. Such as, people who pay for HBO and Cinemax.

In other words, yes I did use the right terms.

ahh yes i forgot we were talking about cable as well, as in cable tv… because it does apply in that situation… carry on

Yeah, I was doing a comparison, since the OP was doubting whether there was any benefit to DSL. Phone service is unicast, or at least it’s a lot closer to being unicast than cable is.
this isn’t about pots or tv…… this is about dsl and cable data.

Yes, data is what it’s about. But that data is transmitted across the same infrastructure as phone service and TV service, hence the layout of that infrastructure is relevant to the conversation. Phone systems have to support all customers at full bandwidth all the time (at least up to the regional backbones), and cable doesn’t. Which is why DSL’s data throughput is more reliable than cable’s.

If the ISP doesn’t have the bandwidth it still won’t make any difference.

um, no, actually it doesn’t go over the same infastructure…. It’s the same network for the "last mile" but once it gets to the CO then it’s diff.

telcos, for example, generally use IP networks (and some legacy ATM) for their data backhaul (packet-switched) but they use SS7 switched networks for voice. Completely different.

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