Hi All,

I have my own dedicated server. My ISP use a formula to caluate my bandwidth :

(avg. in) + (avg. out) / 8 (bits) x 60 (seconds) x 60 (minutes) x 24 (hours) x 30.5 (days) = Total Bandwidth

When I looked at my own stats report (AWStats http://awstats.sourceforge.net/), the total bandwidth is around 350GB. But my ISP MRTG report shows that I have around 700GB total bandwidth for that month.

I would like to know will there such a great differences between MRTG and AWStats? There might be a differences but I don't think there is 100% differences.

I would also like to know does ISP usually caluate incoming traffic (upload, incoming hits...) ?

Any comments are welcome.

Max

That formula is reasonable for calculating average usage. One difference between your number and your host's is that MRTG reports show all of your servers bandwidth usage while it looks like your number (based on a quick glance at the AWStats homepage) is just based on outgoing http traffic. Your numbers don't include telnet, ftp, email, or anything else that you have running. 350 gigs of other use seems like a lot, but it's far from impossible. Do you have much ftp traffic?


-Joe

I am not familiar with AWStats, but it seems to be a standard "WEB" log analyzer.

Here is the difference:

AWStats will give you the approximate HTTP traffic transfer because it knows how large and how often the web pages are used and calculates it based upon that.

MRTG polls your port on a switch/router and calculates the "Total" bandwidth the transverses your port; HTTP, FTP, Mail, etc.

Hope that help!

Not really. I don't much ftp traffic. I just do some simple uploading. The file size is small too.

Besides of it, I don't even have mail, or any other services at that server. Just only web server.

I just worry they might cheat on that figure. Is it possible to cheat on MRTG report?

Max

It's possible, but maybe they are reporting to you a wrong port? Even if you do not have any additional services installed, but web, MRTG will show more traffic than AWStats because there is also general network noise; broadcast packets, etc. (It should not be double though)

Thanks a lot.

I think so. The figure is not only 10GB or 20GB. It's double from my own stats report and that's why I worry about it.

So how much more bandwidth do you think is normal compare with MRTG and general web log analyzer?

Let me see if I can dig up some info on a comparison.

If AWStats calculates bandwidth based on averages or even just 'total bandwidth' and your hosting company uses MRTG to calculate bandwidth based on 95th percentile, this might explain it -- especially if you have particularly 'bursty' traffic going to/from your server.

If you burst for 6% of the time per month (43 hours total, per month) at around 2 mbit this would be right around 700GB usage for the month (if I'm not mistaken).

Dan

Thanks.

Is this caluation method called 95th percentile?

Yes, my server sometimes get a lot of traffic suddenly and then back to lower level.

So which caluation method can gvie me lower figure for my situation?

Max

Maxbear, you need to ask your provider how you are billed (something you probably should have asked before, but it is ok).

Definitely find out if you are being billed for average or 95th percentile usage. The formula you gave in your original post calculates average usage based on MTRG data.

-Joe

Good point, sound like they are using a 95th percent/GB calculation. It's normally 1.5 - 2X your average use.

I asked them. They said the are not using 95th percent/GB calculation.

But why Rackmy said they are using 95th percent/GB calculation?

So which method they caluate my BW?

Where can I find the formula for 95th percent/GB and average caluation?

This is just a short explanation, not a formula:

Average
Billed as the average of your traffic (spikes and all).

95 Percentile
Similar, yet you are billed at the highest rate (Mbps) you needed that month, minus the top 5% for the whole month. Where this hurts is if you were to get very heavy traffic the last week of the billing month, you'd be billed as if you were using the full speed all month long (minus the top 5%).

When you say, "the total bandwidth is around 350GB. But my ISP MRTG report shows that I have around 700GB total bandwidth for that month" - this is a bit confusing as you didn't list bandwidth, you listed transfer (total amount of data moved). Thus, I'm sure if listing bandwidth calculations is going to help you much.

When you said, "So which method they caluate my BW?" - you should ask your provider this.

Thanks Chicken.

My ISP told me they use this formula to caluate how much data I transfer for a month and bill me according to this.

(avg. in) + (avg. out) / 8 (bits) x 60 (seconds) x 60 (minutes) x 24 (hours) x 30.5 (days) = Total Data Transfer

So is it a 95 Percentile or Average method?