bandwidth

[jes]

I am thinking about contacting my ISP for a faster Internet connection as I find myself downloading alot lately but I wonder, would that make any difference for a home user? Wouldn't I only be able to receive as fast as the server can send?

[PrntRhd]

Yes and No:
I have had dial up, DSL, and Cable.
Dial up fastest downloads were 6k with a 56K modem.
DSL was about 35K due to distance to the phone company switch, which limits the speed regardless of the DSL speed tier you contract for.
Cable has been 492K on a 6MB/1MB tier. I get up to 15101 Kbps/1421 Kbps at times on my cable connection.

Yes the server on the other end affects the speed, but the big sites have enough server capacity to make the downloads really crank along.

[jes]

I left out some important information. This (https://commerce.sasktel.com/eSales/start.swe?SWECmd=InvokeMethod&SWEMethod=Linkup&SWEService=SKTL+eSales+Link+Service&ViewName=Product+Catalog+Category+Detail+View+-+Product+Rich+(eSales)&BusObject=Catalog&BusComp=Catalog+Category&Id=1-JMO1R&SWERF=1&SMIDENTITY=NO) is what I have. I don't know about the server capacity of the places from wich I am downloading. I suppose that I could try it for a month and see what difference it makes. Thanks for the advice.

[PrntRhd]

I just love "big pipes" for the connection.
Speed Kills.
:)

Have you done a speed test for your current connection?
What speed tier are you on?

[jes]

I don't know what speed tier I am on. How do I test that?

I understand that my ISP is constricting my download speed now and if I pay for a higher speed they just constrict is less. How can they justify doing this? Is there more upkeep for them when they allow a higher transfer rate?

[PrntRhd]

Your tier or description of the service is shown on your bill.

One decent speedtest site:
http://www.dslreports.com/speedtest

A true speed test is to download a large file (with known filesize) from a fast server and time the download. Divide the filesize by the time to get the speed of the connection.

[jes]

My bill show nothing pertaining to the speed but the site that I tried to link to a few posts ago says up to 1.5 MBPS. Is that the correct format that I am looking for?

[PrntRhd]

My bill show nothing pertaining to the speed but the site that I tried to link to a few posts ago says up to 1.5 MBPS. Is that the correct format that I am looking for?
Yes that would be their High Speed Basic Internet service tier.
Their Plus service is up to 5Mbs
Their Extreme service is up to 10Mbs.

Did you try the speed test?

[jes]

Open Office install file from www.download.com (120.1 MB) - 10:36 to 10:47.47

120.1 / 11.47 = 10.47 I suppose that is MB/s. Is that the right way?

[PrntRhd]

No, you want to divide by the number of seconds.
Should work out to be about 16.67kbs

[Cuc Tu]

Isn't it bits per second?

120MB = 120MB * 8 bits = 960 Mbits

then divide by seconds...960 / 707 = 1.4 Mbps

If you have high speed DSL, that is what you would expect.

[johnny_quest]

I understand that my ISP is constricting my download speed now and if I pay for a higher speed they just constrict is less. How can they justify doing this? Is there more upkeep for them when they allow a higher transfer rate?

No it costs them no more per-se. They can "justify" it because, well, it's there business and they are selling a product, they can do whatever they want.

I have the cheapest cable connection in my area, $15/month for 768kb. I do have problems streaming video, Youtube, CNN, NBC TV shows, etc. It just can't download as fast as it plays.

It's still very fast though relatively speaking for everything else.

[Paul Komski]

it costs them no more per-se
This implies that the bandwidth that the ISP itself purchases is infinite and for free.

[PrntRhd]

The ISP usually sees it differently, they see tiers as payment for the quality of service provided. In their marketing plan you should pay more for a premium quality service vs basic service.

[Whyzman]

I understand that my ISP is constricting my download speed now and if I pay for a higher speed they just constrict is less. How can they justify doing this? Is there more upkeep for them when they allow a higher transfer rate?<Italics mine>Probably a 50¢ one time filter...they'll happily remove for whatever the upgrade amount is...being paid monthly! ;)

[mjc]

Do you know, on a traditional land line, it costs more to block 'optional' services than it costs to provide them?

Take a good look at the bandwidth/price...

The levels are usually a multiple of a lower level...now think about this...

If they are paying the same amount for raw bandwidth for all their customers, wouldn't it make sense to try to get as many customers as possible without buying more 'raw' bandwidth?

The basic level is one price, but about half as fast as the next level up, which isn't quite twice the price...so on the basic level one customer is paying for the raw bandwidth and the other is paying most of the profit. Move up to that second level and now you pay both...

Work up the levels.

Cynical?

Probably.

[Paul Komski]

At a practical and functional level, can anyone explain how the contention ratio is controlled for any given service?

[Variable]

Contention ratio in regards to rate limiting?

Bandwidth works both ways. ISP's pay for a pipe, say they have 100Mbps
This is constant throughput up and down. You have customers at a tiered level. Customer’s bandwidth is normally bursty, the traffic goes up and down. ISP's pipe is constant throughput. Your pipe, as a consumer, is not constant. You pay for a rate limited pipe BUT your ISP has a set amount of bandwidth. If all users used their maximum download rate all the time, you as a consumer would complain because you would not get your say 6Mbps. Luckily, consumers traffic is bursty, so you as an ISP need to buy enough bandwidth to cover a set amount of peak load. You watch your load graphs and when you start maxing your pipe too often you buy more bandwidth or you start rate limiting ports for kids downloading bittorrent files :)

Rate limiting can be asymmetric or symmetric, i.e. upload speed can be one speed, download another. Consumers want Download speed, so the pipe is waited heavily incoming. Most ISP's have huge amounts of wasted speed up, because of how consumers use the pipe.

Rate limiting is applied as one line in the router. There is not a physical filter. It is simply a line in the config that limits your connection. When you exceed the connection the packets are dropped. Since most meaningful traffic is TCP, the dropped packet is requested again by the far side. When you move up a tier with your ISP to gain more bandwidth, the line in the routers config is changed. That is all it is. Nothing magic.

I understand that my ISP is constricting my download speed now and if I pay for a higher speed they just constrict is less. How can they justify doing this? Is there more upkeep for them when they allow a higher transfer rate?


You have got to be kidding? How can they justify making you pay for bandwidth? You pay one rate for bandwidth, your ISP pays a rate for bandwidth, they get it cheaper than you and charge enough to cover the expense and make a profit. If they charge too much you may go elsewhere, so rates are pretty competitive.

[PrntRhd]

Comcast uses Sandvine to throttle bit torrents per a released customer list from Sandvine but this is being denied by Comcast.
More on how the Sandvine net appliance works:
http://en.wikipedia.org/wiki/BitTorrent_protocol_encryption
The Sandvine net appliance uses a different approach to disrupt BitTorrent traffic that makes seeding impossible. The Sandvine net appliance intercepts peer-to-tracker communication to identify peers based on the IP address and port numbers in the peer list returned from the tracker. When Sandvine later sees connections to peers in the intercepted peer lists, it may (according to policy) break these connections by sending counterfeit TCP resets.

This interferes with your connection on the web, but may be legal if Comcast's lawyers can convince the FCC that the traffic shaping is "reasonable" for traffic management purposes.

[Variable]

If your a huge ISP, you have to look at the numbers. Since you can safely assume most of the Torrent files are not legal, it is easy for the bean counters to step in and say "woah nelly." You have to keep in mind that NO ISP of any size, could afford to have all their clients using max bandwidth 24/7. They would go broke or raise the fees big time. If you average out the numbers, you can afford to have a few Grandmas paying for 6 Mbps using an average of 34K and a 15 year old maxing the 6Mbps on his parents connection downloading porn ISO's. When your numbers start swinging towards more 15 year olds than Grandma's, you got problems. At least they are not dumping the packets to a SAN and giving access to Sony's legal department. They just quietly kill your bandwidth. Very non-judgmental isn't it?

[Paul Komski]

Contention ratio in regards to rate limiting?
No. I was wondering if the ratio is simply the number of potential connections or if it was more complicated than that. For example one connection might have multiple PCs and be absorbing more bandwidth than another connection using the internet less. If say there is a contention ration of 10 and a purchased bandwidth of 2000kbs does that mean that the minimum bandwidth should not fall below 200kbs or does it simply mean that no more than 10 connections can share the alloted 2000kbs? :confused:

[Variable]

That depends on where the Rate limiting is done. Since we are talking about ISP's, generally your pipe is rate limited from the ISP side. So if on your side you have 10 computers connected to a router and that router is connected to your ISP through a modem or whatever, all 10 machines have access to the same pipe, which is rate limited on the far side or ISP side. From the ISP router point of view all your packets are coming to it so it is not actively making too many descisions. Once the packet count exceeds the the rate limit threshold the routers starts dropping packets.
Things to keep in mind as a general rule. TCP has priority over UDP, established connections have priority over new connections.

Contention Ratio is not a service or rule in a router, it is an equation from bean counters. You have X number of users for X number of bandwidth. It is a term for a ratio of how many users share a set amount of bandwidth.

[PrntRhd]

Sandvine is interesting in that the devices are at the periphery of the ISP's network.
This means they do not throttle in-house applications such as ads and email, and they don't severely throttle torrent seeding from users within the ISP's network. Once a seed is responded to outside the network the limitations kick in. Say you are using Comcast and you get a file from a friend also on Comcast's network, no slowdown is seen, but say you go outside the network to say PirateBay, the throttling is immediately in evidence. You will eventually get the file, but the speed may be only 3-7% of the usual speed.

[Variable]

Paul did you get your question answered?

[Paul Komski]

did you get your question answeredI think so - if I have understood "bean counting". That is to say that with a ratio of say 10 then if one ISP client is constantly utilising a lot of bandwidth (say with 5 pcs all downloading torrents simultaneously) it will significantly have an adverse effect on the remaining 9 users sharing the same bandwidth. Or, in other words, on a 2MB service users could have a functional rate significantly less than 200kB (10%) if one of the 10 was absorbing a large amount of the 2MB allocated to the 10.

[Variable]

Sorry for the slang, "bean counters" are the accounting people, the ones who make sure that say, each can of beans has exactly 50 beans. Any more than 50 and they are losing money. Dunno where the term comes from.

Yes, you have the idea. The ratio is not a big deal assuming normal traffic, but when you through in down loaders pulling down constant streams of packets your destroying the premise of the bean counters original ratio. They need to reassess their ratio or ... slow down the down loaders.