Released by Sentech Today

[Dean_Henstock]

Hi,

Recived this in email from (Nowire) One of Sentech's partners.

"""""""""
MyWireless Service has a Contention Ratio of 30:1.
Telkom’s ADSL has a Contention Ratio of 60:1
Telkom’s Diginet Line has a Contention Ratio of 1:1.


Contention Ratio means purely that for example a 128kbps connection is being shared by the number of users indicated by the Contention Ratio figure.

A 128kbps of 30:1 is a dedicated 128kbps (1:1) being shared by 30 users. (128 / 30 = 4.26kbps)
The above mentioned figure is just in the worst case scenarios, like now. (Bandwidth is not managed correctly).

But in a ideal scenario when bandwidth is managed accordingly speed then will be available constantly as each user will be assigned constantly, according to amount of users on the network, the right and fair amount of bandwidth speed.

The average recorded speed at this point of time is: 128kbps between 30kbps and 60kbps
256kbps between 60kbps and 90-110kbps
512kbps between 80kbps and 140kbps


""""""""""""""""""


Keep Surfing

 

[regardtv]

too bad many 256kbps users are seeing sub 128kbps speeds

 

[playkiller no.2]

Wait 30kbps is that not slower than a 36k modem.

 

[Kai]

what a load of crap!!!!

do they SERIOUSLY expect people to pay R860 a month for 60kbps!?!?! that's the stupidist thing i've heard in a long time!

I can't believe this crap! honestly!

<hr noshade size="1"><font size="1"><i><div align="right"><font color="red">one day we will all look back at this... laugh nervously... and change the subject...</font id="red">
tower82.randparkridge.jhb|13-21% signal|256k package, running at 0.3 - 3k/s </div id="right"></i></font id="size1">

 

[playkiller no.2]

So that`s 4kbps shorter than a 64k isdn.

 

[Dean_Henstock]

Yip, and this is there document on the share ratio !,

So guys this is what is to be expected ! Got to wonder if going back to my ADSL at home wont be better.

Keep Surfing

 

[playkiller no.2]

Oooh I pray Iburst will better,then I can dump my stone age 56k dial-up.
If they watching,please no contract like Sentech,cause people will say whats the catch.

 

[Dean_Henstock]

One thing that you have to remeber !

International bandwidth cost huge amounts. Becuase of the Telkom Monopoly.

The avergae an ISP can land 1:1 International bandwidth including SAT-3 Cost, Telkom Cost and Upstream provider cost is about R 5 000 for the big guys like IS it comes down to about R 3 500 for 64 on a 1:1 so if you work on that basis, you will see why they put contention rates in, so while I hope Iburst will better if you work on the above can you see why there is a bandwidth problem.

Keep Surfing

 

[bHOLDher]

Have they specified black on white what this entity is that has a 30:1 ratio?

saying that Mywireless has a 30:1 contention ratio is like saying a chair is shared 20:1. WTF? Does this make any more or less sense to anybody?

Towers have 12Mbps to 48Mbps bandwidth... Sure thing, lets share that between 30 people!

Its just another one of those useless facts....

 

[GougedEye]

Agree Dean.

I think there is a huge expectation gap here. You will never get decent international bandwidth in this country. It's the law. No really, it IS the law. You can go read up on it. Telkom is a private company run by Americans with a license to RAPE the SA public. And our wonderouse Minister of Telkom's Ivy wassisname couldn't organise a pissup in a brewery. I mean what the hell does she do all day? She sure as hell doesn't do anything to protect the interest of the SA public which she is meant to serve. I guess she is better than the Health minister who is actively trying to kill the people she is meant to serve (really, you can look it up). Gartner has reported that the stated aims of SA telecomunications policy are exactly the opposite of SA telcoms legislation. Report after report highlights that Telkom is butt raping us without KY and that we desperately need either competition or effective regulation. And what happens? The SNO is repeatedly postponed thats what. So what the hell is the esteemed minister doing all day? Cheating on her travel claims no doubt. Point is, noboddy can give you decent bandwidth at an even remotely reasonable cost (legally). Rapekom simply doesn't think that that would give them the most economic advantage.

Having said that, Sentech is still a balls up. Local bandwidth which is cheap is as bad as international bandwidth. Local packet loss is very high. MyWiresless 128should be able to provide a comparable service to 2xISDN, although with slightly higher latency. International bandwidth is no cheaper for ISDN, nor bandwidth management any less of a priority. So either their network management is a screw up, or their backbone is a screw up, or IPW is inherently a screw up, or their peering is a screw up, or they have a maximum IQ requirement for technicians, or they are just plain stingy or (most likely) a combination of the above.

 

[arf9999]

This whole talk of contention ratio is cr@p. The argument that there is 30:1 contention which means that on a 128k package, you can expect 4kbps is just sh*t. 30:1 contention means that for the entire pool of 128k users there will be a maximum of 30 users per 128k of {international?} bandwidth. It doesn't mean that every 128k of bandwidth is divided by 30.

i.e.lets say there are 1000 128k subscribers, that means that Sentech needs to offer more than 128k x 1000/30 bandwidth. So at any time there should be a absolute minimum of approx 4.2Mbps of bandwidth available for the 128k users. Their bandwidth management system should allocate this bandwidth fairly amongst those users. It VERY unlikely that every single subscriber is not only online but actively downloading information at the very same instant - but that is what is required for the minimum situation that they claim as acceptable. In reality, each user should find that even with contention, they get reasonable service even though it is very rarely at the maximum that the package is capable of. On ADSL it is rare to find a user complaining that they only get 128k speed downloads, despite the fact that according to Sentech, they should be happy to get 9kbps. This is because Telkom (for all their sins) manage the bandwidth correctly, and ensure that they have enough bandwidth in the pool available to their users. It is very rare to get less than 40% of max bandwidth on ADSL, but seems to be rare to receive more than this on MyWireless.

In short: Their network is fscked, their management is fscked and their customer service is fscked...14 days and counting to deadline.

 

[Dean_Henstock]

Agreed,

However, and this is in no way in defense of them, its is extremely difficult to do bandwidth management with all the apps out there that use multiple threads to achive maximum throughput, however if items like

Packteers were used, I am sure that they would get closer to a happy medium, on a second note, they dont specificaly say that there is a pool of 1000 user then divided by a 1:30 contention ratio, so no one really knows, including them.

Keep Surfing

 

[arf9999]

Hi Dean,

My figure of 1000 is just for example, and I understand your point. But Sentech didn't just decide to become an ISP overnight, bandwidth management is the core of their business and should have been in place when they started. Crying foul now, and saying that users are abusing the system is just pitiful.

Also what is important that people realise that when someone quotes a contention ratio, what it should mean is that "There will never be more than 30 (or whatever number) of users contending for the same BW" and not "Hey, there are definitely 29 other people using the same bw all the time, sorry. Now f$ck off."

-A

 

[Dean_Henstock]

Fair comment,

but I just wannted to point out to the people waiting for iburst the prices of bandwidth namely international so they dont get there hopes up yet.


Keep Surfing

 

[Mean_Monster]

arf99999,

I don't think Telkom are so much managing that bandwith as controlling it. Meaning they are currently making the price for all other ISP's. So they get it at cost, before they add those ridiculous profit margins. So where all other ISP's are paying R 5000 per 64K via Diginet, Telkom gets it at cost which is probably a R 1000, which makes it possible for them to let ADSL users have a full go at the line, even with such a high contention ratio. Telkom just has more international bandwith available.

 

[arf9999]

Understood.

International bw is a whole other ball of wax. Which begs the question as to why Sentech's LOCAL bw is so sh*t.

MW128, Tower <b>60</b>(Northpark Plaza), Signal:16%,S-N-L: 7, BER: 45%

 

[Mean_Monster]

yeah that is a good question why locally I can't pull at 16KB/s from you if you on 128k? If that is not even happening then ... that has got nothing to do with International Bandwith. Probably Telkom Backbone?

 

[Torlin]

Does Telkom have a Backbone (YES I KNOW, WAS BEING SACRCASTIC). I think that their config is up to sh**, let me rephrase that I KNOW. That is the most possible reason for the shi** download, not all the mambo jumbo about International Bandwidth and connection ratios.

Sentech a perfect example of: “When great ideas go terrible wrong!”

 

[Torlin]

Sorry about the typos, are coding and replying at the same time....

Sentech a perfect example of: “When great ideas go terrible wrong!”

 

[loosecannon]

bollocks what a load of ****e