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DrugTito
join:2013-01-17
canada

DrugTito

Member

[Cable] need help do some calculations :)

Right now i have 45\10 connection - unlimited.

Since, last night ( »[Cable] Slow ) i am thinking about changing my package to different tier, but, i am not sure yet, what tier it should be.

Having 10 mbit upload going for an hour, how much bandwidth will i see on download side? (not sure if i am asking this correctly, as English is my 2nd language, and i am little lost atm )

I am trying to see, if, in case i leave my upload running for a day, full day (24h) how much will i 'loose' on download allocation from start.

Thanks,
DT

Davesnothere
Change is NOT Necessarily Progress
Premium Member
join:2009-06-15
Canada

Davesnothere

Premium Member

 
Which packages are you considering, if the result may be good enough ?

Are you thinking about not having the unlimited any more, or lowering the download speed to, say, 35, or about doing both of these things ?

jmck
formerly 'shaded'
join:2010-10-02
Ottawa, ON

jmck to DrugTito

Member

to DrugTito
it depends on a lot of things, but uploading at 10Mbit/sec on my VDSL2 and monitoring my network traffic, I see that I'm receiving at 30-35KB/sec (~260Kbit/sec).

if my math is right that would be close to 110MB per hour of download usage.

when you're uploading or sending packets, the only thing coming back really are ACK packets to confirm it was transmitted properly. your computer sends out ACKs too when you download something (unless it's UDP traffic).

cybersaga
join:2011-12-19
Selby, ON

cybersaga to DrugTito

Member

to DrugTito
I found this: »www.winpcap.org/misc/cal ··· tors.htm

According to the footnote, the largest frame size is 1518 bytes. If you punch that into the first calculator at the top, and set bandwidth to 10, you get 812.74 packets per second. That's what your upload will be doing.

For each uploaded packet, there will be an ACK sent back. So you want to know how much bandwidth 812.74 ACK packets will take up. The minimum frame size is 64. Jump down to the 3rd calculator, "Frame rate to bandwidth converter". Punch in 812.74 as the frame rate, and you get 0.545664 Mbps.

0.545664 * 60 seconds * 60 minutes * 24 hours = 47145.3696 Mb/day

Amiright?

Doesn't look right.

Davesnothere
Change is NOT Necessarily Progress
Premium Member
join:2009-06-15
Canada

Davesnothere to jmck

Premium Member

to jmck
 
Or about 2,640MB per 24 hour period.

But you would only need to count 18 hours of that, if you have the Free 2AM - 8AM period.

So then about 1,980MB for that length of time.
Davesnothere

Davesnothere to cybersaga

Premium Member

to cybersaga
said by cybersaga:

.... 0.545664 * 60 * 24 = 785.75616 Mb/day

Amiright?

 
Dunno, but your number is lower than the first estimate from JMCK, above.

And about 3/4 of that gets counted if you factor in the Free period.

jmck
formerly 'shaded'
join:2010-10-02
Ottawa, ON

jmck

Member

it can depend on your packet size, if your packets are smaller then you'll receive a lot more ACKs. really the best thing is to just monitor your upload and see your bytes/sec or bits/sec received while uploading and make a judgement call then.

Davesnothere
Change is NOT Necessarily Progress
Premium Member
join:2009-06-15
Canada

Davesnothere to cybersaga

Premium Member

to cybersaga
said by cybersaga:

.... 0.545664 * 60 seconds * 60 minutes * 24 hours = 47145.3696 Mb/day

Amiright?

Doesn't look right.

 
That's a lot higher than your first estimate.

Hmmmm....

cybersaga
join:2011-12-19
Selby, ON

cybersaga

Member

Yeah, I forgot a *60.

Turns out 1 second * 60 != 1 hour

DrugTito
join:2013-01-17
canada

DrugTito

Member

Thank you guys.

Yes, i am thinking about dropping unlimited, as, i don't see a point of that any longer, to be honest with you (with what happened last night).

I was maybe thinking 25/10 (150GB) and in worst case, even if i have to pay $25 (max overage fee) it will be close to what i am paying now (even less - about $85/mo with max overage fee + tax), but, at least, i would never have to go through the same stuff as last night.

It is 20mbit less for download, but, for my needs it should be enough.

cybersaga
join:2011-12-19
Selby, ON

cybersaga

Member

K, lemme do this math without a fancy web calculator.

According to Cisco, the max total packet size is 1,538 bytes. So...

10Mbits = 10,000,000bits = 1,250,000 bytes
1,250,000 bytes / 1,538 bytes = 812.74 packets / second (same as the fancy web calculator)

Minimum total packet size is 84 bytes.
84 bytes * 812.74 = 68,270.16 bytes/sec * 8 = 546,161.28 bits/sec = 0.54616128 Mbps (roughly same as above)

So yeah, you're looking at ~ 47Gb/day download for saturating your 10Mbps upload for 24 hours.

But I forgot one more calculation: divide by 8 for gigabytes. That comes to around 6GB/day. That makes more sense.

DrugTito
join:2013-01-17
canada

DrugTito

Member

Thank you.

Of course, there is no way that my upload would be full 10 mbit at all time, so, if its around 6GB/day , i would say in 30 days, the most i could do is maybe, around 100-120GB.

This would easily eat all\most of my download limit, so, i am sure that i would have to pay max overage fee each month.

Thanks

Patiences
@carohosting.net

Patiences

Anon

One thing you should ask yourself is what is important to you? Speed? Downloads? Uploads? You should not make any decisions based on what happened last night because clearly it was one of the rare evening which likely do not happen that frequently.

rocca
Start.ca
Premium Member
join:2008-11-16
London, ON

rocca to DrugTito

Premium Member

to DrugTito
Most simple way to calculate it is that for every 1500 byte packet you send you'll get a 64 byte packet in return. 64 / 1500 = 4.3%, so if you upload 100GB you'll download 4.3GB in return packets.
Expand your moderator at work

DrugTito
join:2013-01-17
canada

DrugTito

Member

Re: [Cable] need help do some calculations :)

thanks rocca.

rocca
Start.ca
Premium Member
join:2008-11-16
London, ON

rocca to DrugTito

Premium Member

to DrugTito
said by DrugTito:

I was maybe thinking 25/10 (150GB) and in worst case, even if i have to pay $25 (max overage fee) it will be close to what i am paying now (even less - about $85/mo with max overage fee + tax), but, at least, i would never have to go through the same stuff as last night.

I don't think you'll be happy with that, ie once you cross your $25 overage the speed will continue to be reduced as you keep going past it and won't reset until the start of your next billing period. Last night you went to 8Mbps, the overage protection will be 6Mbps based on the volume you're doing - which is pretty heavy, ie I'd guess you're in our top 10 users.

If your heavy transfers had been restricted to 2-8 you wouldn't have been impacted by the prioritization but as has been mentioned many times, if you're looking for unlimited to be full speed non-stop terrabytes of data on peak, then our $10 plan isn't a good fit and you're going to be disappointed occasionally such as you were last night.

It's simply not financially sustainable to offer a $10/mo package and allow it to be used in a way that costs $600/mo. When there is extra bandwidth then we're happy to give it to you, but when there isn't then you're going to be the one to feel it as part of a fair use policy rather than allow it to continue at 45Mbps and cause congestion for others.
rocca

rocca to DrugTito

Premium Member

to DrugTito
My pleasure, and sorry I don't have the answer you want to hear.

DrugTito
join:2013-01-17
canada

DrugTito

Member

I see, and i understand now, thanks for clearing things up for me.

As you stated last night, last night was critical, as, most of ppl were using internet more then usual, so, hopefully, its not going to be that slow, as it was last night.

Not sure right now what is the best for my needs then :\

Need to think more, anyway, its start of the month, i have 20+ days to think before i make decision, and i am very thankful to you guys (all of you) for answering here in this thread.

jmck
formerly 'shaded'
join:2010-10-02
Ottawa, ON

jmck

Member

it might be worth waiting a week or so too, rocca mentioned more capacity was being added, if that's the case I assume a second 10GE?

DrugTito
join:2013-01-17
canada

DrugTito

Member

yes sir, i will have to do some 'waiting' and some 'thinking'

FTTHTechie
@pathcom.com

FTTHTechie to jmck

Anon

to jmck
said by jmck:

it might be worth waiting a week or so too, rocca mentioned more capacity was being added, if that's the case I assume a second 10GE?

Exactly that's what it is. A second 10Ge should help to ease any kind of network congestion or load and should help to ensure ample capacity (as it would be 2x10Ge links) for the subscriber base Start has.

DrugTito
join:2013-01-17
canada

DrugTito

Member

In that case, i might even stay where i am now, if that happens \ helps, will see

Davesnothere
Change is NOT Necessarily Progress
Premium Member
join:2009-06-15
Canada

Davesnothere to rocca

Premium Member

to rocca
said by rocca:

Most simple way to calculate it is that for every 1500 byte packet you send you'll get a 64 byte packet in return. 64 / 1500 = 4.3%, so if you upload 100GB you'll download 4.3GB in return packets.

 
I have heard of a 20:1 ratio being mentioned from time to time.

What you just posted is pretty close to that.