ISP bandwidth explanation

I am currently drawing swords with my ISP who advertise 'Unlimited broadband'. I am paying for a 10 Mg connection but on average it is 2 Mg or less. I accept that it is impossible to obtain a constant 10 Mg Connection, but some where closer to that than dial up would be nice. I have on a few occassions been fortunate enough to have been told by the ISP reps that they have an over utilisation problem, but most of the time they try to deny this and attempt to waste my time with the usual checks. This has gone on for over a year and I have lost patience.

In order to move forward on this I need to be 100% sure of my facts, which is why I have come to Experts Exchange.

For this excecise please assume I know didly squat about IT.

I need to have broadband explained in full and clearly in order to refute their claims, which have included "Well it refers to the amount of data you can download" etc. Their constant argument is they advertise 'upto' 10 Mg. My contention is that is I'm paying for up to 10 Mg then I should receive at least 50% of that. Answers should include details of ISP servers/modems, over utilisation, over booking, bandwidth terminology (upstream/downstream etc). It would also be useful if anyone has any information about a method to log the available bandwidth on an almost consant basis.

Please see my petition at for the full story if necessary.
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KeyguardConnect With a Mentor Commented:
And usually when they say Mb/s they mean MegaBits - a bit is 1/8 of a byte so a 1Mbs connection will only transfer data at 125Kbytes per second.

This sort of problem has become more common in the UK recently with ISPs starting to do ADSLMax - they usually advertise this as "up to 8Mbs", but it is very connection quality dependant, you won't get close to 8Mb unless you live nextdoor to the telephone exchange.

You don't say what you're using to measure your connection speed, is the 2Mb what the modem is reporting for the connection speed or the figure you get from an online connection speedtest? There's two factors at work here, the speed your connection has negotiated (which with DSL will be dependant on type of service, line quality etc.) and then the actual data throughput you're getting from the ISP for your internet access. Its this second figure which is affected by the contention ratio (basically how many other users you're sharing the connection with), ISPs work on the theory that since most people's internet usage is intermittent they can get away with sharing the connection amongst a number of users. This is often one of the key differences between "domestic" and "business" DSL services, the business ones offer much lower contention ratios (can be 10:1 compared to 50:1) because business use tends to be consistently heavier than domestic.

In terms of arguing with your current ISP I'd suggest that you're probably wasting your time and if its gone on for over a year then you'll probably be able to cancel your contract without a penalty anyway. They know that most of their speed claims are marketing speak and their small print will reflect that, I expect it will cover them. You can't really get any decent guarantees for speed/service unless you go for the much more expensive leased line type connections which come with Service Level Agreements, these include compensation rates if the ISP doesn't deliver. I'd guess your ISP is offering what looks like a pretty good deal in terms of connection speed/price and so they're getting a lot of subscribers, unfortunately as pjtemplin says, they're still paying pretty much the same for their bandwidth and so to make their profit margin they just spread it a bit thinner amongst the users.

For testing your connection speed I've used Dan Elwell's tester at before but I can't remember if it allows you to run extended tests over a certain length of time. If you're shopping round for a new ISP I'd suggest you look closely at what contention ratios they offer, proper business class services may look expensive at first but they do offer a better service.
pjtemplinConnect With a Mentor Commented:
How much are you paying per month for this connection?

Your Internet traffic doesn't go through servers or modems.  If DSL, it goes through a DSL Access Multiplexer (DSLAM) and possibly through an ATM network, then on through routers and out to the Internet.

Yeah, there's oversubscription.  If you didn't expect that, I'm sorry to hear that.  In the major carrier hotels, bandwidth is running $30-75 per Mbps when purchased in quantities of 100Mbps or more, occasionally less for some networks, specials, etc.  Add in a transport network to get from those locations out to the various central offices where the users are, the equipment to do that, etc., and you've got even more costs to deal with.  If you figure a cost structure of $50/Mbps and you're paying $100/month, 2Mbps should be all you expect.  If you're paying less, your expectations just might be too high; if you're paying more, just refigure the numbers, etc.
dlangrConnect With a Mentor Commented:
apart from oversubscription, you might be located to far away from the dsl equiptment on the other side of your phone line to get a decent enough signal. Where i live (netherlands) most providers won't even provide their service when they cannot deliver reasonable speed because you are to far away. Even if the distance is ok, it can happen that the signal is not strong enough. They warn you up front (at least, here they do) that the 10mbps is not guaranteed. Usually they do specify a minimum speed though.
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and i forgot, the 10mbps refers to the maximum download speed under optimal circumstances, not to the amound of data.
giltjrConnect With a Mentor Commented:
--> My contention is that is I'm paying for up to 10 Mg then I should receive at least 50% of that.

Wrong contention.  Say you have a 10 Mbps connection and you are accessing my web sever and I only have a 3 Mbps connection.  You contention is that you should be able to get 50% of 10 Mbps, which is 5 Mbps.  However I only have 3 Mbps, so the best you could get is 3 Mpbs.  That assumes that nobody else is accessing my web sever.

Now the other problem that small documents (3-10KBytes) can really make full use of high speed connections (1.5Mbps and above).  This is because of something called TCP slow start.

With 10 Mbps my guess is that you are on cable.  Cable is shared at the neighborhood level.  Your neighborhood may have a total of 100 Mbps with each customer limited to a maximum of 10 Mbps.  So if you have 30 houses in your neighborhood that all have cable Internet, that is a total of 300 Mbps, but there is only 100 Mbps for the whole neighborhood.  So if all 30 people try to do something at the same time the best anybody will get is 1/30th of 100 Mbps or about 3.3 Mbps.

Broadband is generally asymmetrical.  That is the speed in each direction is different.  You have 10 Mbps downstream, but you may only have 384 Kbps upstream.  In some situations because the upstream is much less that downstream you will not be able to get the full down stream speed.  Example: Say you are downloading a 3GB file, will every so often your  computer must send a ACK to the sever to let it know you have received data and it is safe to send more.  Now say you send out a e-mail that has a 1MB picture.  You upstream side will be saturated at 100% 25-30 seconds.  So for this 25-30 seconds the ACKs your computer sends out will be queued up behind your e-mail.  now it will not be queue up behind the whole thing.  Just like you must ACK the download sever, the e-mail sever must ACK you.  So your ACK's to the download sever will be interleaved with your e-mail.

Anything else?
nunn101Author Commented:
pjtemplin, yeah, I expect them to oversubscribe, but this is becoming quite excessive. I'm with cable paying £35 ($70) per month for ten Mb. If I was paying £50 for 2Mb I'd be suicidal.

dlangr, granted there's distance etc to take into consideration and I don't ever expect to reach 10Mb, it's unrealistic. But why pay for the 10 when others are paying for 4 and I'm only getting 2? Thanks for the confirmation regarding the 10Mb referring to speed and not data quantity. I couldn't believe he came out with that one LOL!

Keyguard, I use Dan Elwell's, several online testers, pathping, and downloads from the ISP's test server. These all confirm the connection is low more often than not and Elwell's reported a packet loss of around 60% over repeated tests. Fluctuation is expected but the overall average is around 2Mb which I feel is unnacceptable. This is to say nothing of the down time.

giltjr, understandably I'm going to suffer slow downloads from a swamped site or one with limited bandwidth, but when conducting the various tests mentioned above I would expect far better results. I'd like to know that when I hit that 3Mb download site I'm going to be able to get 3Mb download speeds instead of the measly 1k and under reported at times. Broadband being assymetrical and most of my work involving uploads only makes matters worse. If I'm downloading at 10k what's my upload going to be!?

Thanks guys, lots of decent info there. Methinks a way forward may be to become an ISP! ROTF!
You may want to try using a Web100 test sever.  There could be some tweaks for you OS that may improve your download speeds.  The closest one to you is

You may also want to try:

If you are getting 10kbps, or even 10KBps, I would say that either you have some serious tweaking to do on your box, your ISP is WAY over subscribed, or there is seriou network issues on your ISP's network someplace.

I don't think it is tweaking on your OS, as even the default for Windows should do bettet than that.

Of couse the other issue may be latency.  By chance are the severs you access in Antartica? :)
nunn101Author Commented:
Cheers giltjr, handy links there.

Web100 reports excessive packet queueing. More confirmation.

Nah, I don't think any tweaking would help significantly.

The servers may as well be in antartica.... under several hundred miles of ice!
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