Contention Ratio's

[aftermath]

I was under the impression that the contention ratio was 20-1. I must be losing my mind....and it's not backed up anywhere....

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Please be advised that the bandwidth on the Sentech website with regards to the MyWireless product is advertised as shared. This means that you will be sharing a perring link of either 128kbps, 256kbps or 512kbps with up to 29 other users.

At times when there are 30 users on one peering link, the minimum bandwith achieved will be as follows:

128kbps package: 4.27kbps
256kbps package: 8.53kbps
512kbps package: 17.07kbps

Regards
Tristan
Sentech Support
0860 736 832

 

[Perdition]

I think he should also have explained what a "perring link" is []

This basically equates to 0.53KB/s, 1.07KB/s and 2.13KB/s respectively... yep I'm sure everyone on the 512k package will be extremely happy paying R1500 per month for a constant 2.13KB/s.

 

[regardtv]

Lets just hope I don't end up sharing my contention with the likes of noone ;-) .. hehehe

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The views expressed on this site are my own and NOT those of my employer.

 

[gripen]

so which 29 people do you "share" with? Since its unfair for you to land in a group of 30 where there are say 20 porn downloaders. I wish they would quit it with this explanation. You arent sharing your bandwidth with 29 others. I dont think even they (such as Tristan) have a clue about how it works. This is the explantion derived from 30:1

He never says "but dont worry, it should never go that low" because not all 30 people are downloading as fast as possible. Unless (in their world) your happen to land up in one of those "bad" groups of 30.

For the uninformed, 30:1 means that you arent sharing 128Kbps with 29 people but rather sharing say, 30Mbps : 7000 users. This still implies 30:1 but you can see that its pretty crazy to expect all 7000 people to be downloading all at once. Now lets say Sentech has 50Mbps and 4000 users (my guesstimate since these two numbers are protected by 6 levels of encryption) then the contention ratio has not even been applied yet.

This all of course depends on just how fairly they are spreading or contending their available bandwidth. Their software could be crap thats why some get more than others but its still no reason to use the CR as an excuse.

If he says you get x speed because of CR's and you AND I have 128kbps then we should both get exactly the same min/max speed. This is most definitely not the case.

 

[Rhino]

*blink* *blink again*

Please can sum1 explain in ENGLISH wot this contention thing is....

 

[gripen]

Sentech takes a large bandwidth (available speed for sentech as a whole) and divides it amongst the user base. To keep costs down, they dont give everyone their full package share which means a dedicated 128kbps slot or whatever. Instead, they divide it so you get about 30kbps slot. Now in reality its not that bad. The detailed explanation is very important to see why not.

Really they are just buying less bandwidth than what they *should* be buying. This is the nature of contention. Unfortunately, it has to be done. But it does make sense since an idle user's bandwidth can be put to good use by some other users. This keeps costs down for all.