Contention Ratio

patrickc

this might be a silly question, but I'm with utv and I'm on a 1:48 ratio. does that mean i share with other people in this area on dsl who are connected to any broadband provider or how does it work?

Nody

patrickc2006 wrote:

this might be a silly question, but I'm with utv and I'm on a 1:48 ratio. does that mean i share with other people in this area on dsl who are connected to any broadband provider or how does it work?

You only share your bandwidth with people from the same company. Also they don't need to be on the same area, they can put your contention at a later stage (for example have 4800 people with 1 MB sharing a 1GB line (yes I know it is 1024 but I'm lazy!)).

Liam Byrne

This topic is a real "bone of contention" . Many people will ignore contention as a factor.

Fact is, you are "theoretically" sharing with 48 people at any one time; if you actually were sharing with all of them simultaneoulsy, then your 2Mb line would drop to 42Kbps - about the average speed of a dial-up connection.

But the fact is also that the chances of all 48 people being on and downloading at the same time is slim, so many people ignore the contention.

IMHO, that's short-sighted. While you may never have THAT number of people online simultaneously, you definitely have a hugely increased chance of sharing with 8 or 9 people at any one time, reducing your speed significantly.

The final fact is that the backbone that you're connecting to needs to be comparable in order for the contention to show a significant impact. If you were connected to a provider with a very poor backbone network, that might slow you down as much as the contention.

So, to sum up, contention isn't the be-all and end-all, but it is a factor, especially as more people get BB and (if it ever happens) that a lot of people start working from home....

If a contended network is significantly cheaper, it's worth considering, but the only way to guarantee that you won't be sharing what you're paying for with ANYONE is to go contention-free.

At the moment, with Smart and Magnet significantly cheaper than eircom and their resellers, that comparison is upside-down - highly-contended networks, with their increased chance of the need to share your bandwidth, are much dearer than the 1:1 options that are available.....and the 1:1 options are also faster to begin with! Go figure....!

patrickc

smart isnt available here and i heard magnet is pricy, i usually dont have that many problems with it.. Thanks for the info

patrickc

magnet isnt in carlow either... just checked

Dcully

Well im suffering major contention issues the past 4 months.
Ive had flawless speeds for close on 2 years,now since my area is getting really populated and i assume many more users of bb at peak times my connection slows down to sub dial up speeds.
Its a right pain in the ass,im on 3mb eircom bb.
Apparently eircom are upgrading the local exchange mid Feb,i hope this helps the issue.
Will it?

JNive

it would if the issue is the uplink from the exchange to the backbone, or if the equipment in the exchange is old and not handling large packet rates well ( depends on what they are upgrading )

watty

Even Magnet & Smart the backbone does not support 1:1. They won't say what the assumed backbone loading is. Unlikely to be much better than 20:1, but only they know.

The more people share an aggregated connection the more the usage averages out so 48:1 on exchange DSL might be good (if no much other usage) or bad (everyone in a Student Village running torrents), 24:1 on a backbone might indeed be 2,400 people rather than 24 people so well averaged.

Iago

Nody wrote:

You only share your bandwidth with people from the same company.

Only partially true...

On a local level you are contended with users on the same exchange as yourself. They could be from any of the bitstream providers that have service in that exchnage and happen to be on the same pipe as you. At most that will be 47 other users.

From there the line is connected to another exchange at which point your contention is increased to all pipes that are coming into that exchange at that given moment in time.

From there you will go onto your own supppliers network and will contend against all users on that network regardless of their location in the country.

From there you will be up against all users who are trying to access the same page/download as you from all over the world (admittedly this normally doesn't have a huge effect, but look how slow boards gets between 12.30-2 and 5.30-6.30)

The actual eventuality of enough users being online and using their service to download at the same time as you so as to really negatively effect your connection is small enough at this stage. I haven't had any major issues as of yet.

JNive

Even Magnet & Smart the backbone does not support 1:1. They won't say what the assumed backbone loading is. Unlikely to be much better than 20:1, but only they know.

Well according to this

www.magnet.ie/glossary/index.shtml wrote:

echnically speaking
The Magnet Entertainment network has been built using the latest technology and to the highest international standards. Unlike many of our largest competitors, the equipment we place in exchanges supports very high speed capacity to our core network and the Internet. In each exchange, at the point that we connect your line to our network, our capacity is greater than the maximum sum of all the capacity we sell to customers connected to that equipment in the exchange.

What it does NOT mean to our customers
"We obviously cannot warranty what congestion may be encountered by our customers beyond our network boundary. Similarly, server capacity with third party networks can adversely effect customer experience. Our undertaking is to supply the best quality broadband experience to our customers within the scope of our operations."

Why we can claim this now?
The Magnet Entertainment network is dimensioned to:

1. Connect our customers to our network in the exchanges in a manner that does not limit the customers bandwidth as a result of sharing this connection with others; and

2. Carry all our active customers' traffic on our network without imposing congestion limits.

3. It is simply a question of math:

a. At the point of connection, the maximum traffic generated by one customer is 16.2 Megabits. Our standard connection equipment contains 48 connection points and uses backhaul links of 1 Gigabit of backhaul capacity. 48 customers X 16.2 Megabits equals a maximum 777.6 Megabits which is less than the 1 Gigabit backhaul capacity in our connection equipment.

b. With respect to congestion beyond the point of connection, our network contains many gigabit links which are dimensioned, monitored and increased from time to time to carry without congestion the maximum load placed on our network by our active customers.

Our core network and the capacity to the internet is similarly dimensioned to telecoms standards in such a way that you will not take a cut in your service when more people get online.

watty

The weasel bit:

b. With respect to congestion beyond the point of connection, our network contains many gigabit links which are dimensioned, monitored and increased from time to time to carry without congestion the maximum load placed on our network by our active customers.

No doubt though it is very good. But not 1:1 from end to end, that would be foolish waste of money, it's not needed!

SeaSide

watty wrote:

foolish waste of money!

Not when you buy on a usage basis.

JNive

the ppoint is, inside ireland it is NOT contended or limited at any stage, or so they say, and as they use the ESB fibre backbone i tend to agree with this assertion.

The first ppoint of 'contention' is their uplinks to their ip transit peers ( cogent, globalcrossing, tiscali ). If your pings are hairy on the magnet hops, they shouldnt be and they need to fix it. if the pings jump outside the magnet network, then fair enough