Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers. I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored. Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s. Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ? I am just interested really - I dont have any experience with high end switches like the Summit. - Is it even possible to set a max bandiwdth on the switch's ports ? If I am off the mark here, can anyone point me at any info explaining how it is implemented. Thanks Whitey
On Sunday 31 October 2004 12:40, Neil White wrote:
Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers.
I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored.
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
I am just interested really - I dont have any experience with high end switches like the Summit. - Is it even possible to set a max bandiwdth on the switch's ports ?
If I am off the mark here, can anyone point me at any info explaining how it is implemented.
One example is found in the package 'wondershaper', part of SuSE Linux >= 9.1 See the manual or /usr/share/docs/packages/wondershaper for more info (no need to install this package if you browse it with mc). I don't know if this is something for professional use. Cheers, Leen
Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers.
I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored.
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
I am just interested really - I dont have any experience with high end switches like the Summit. - Is it even possible to set a max bandiwdth on the switch's ports ?
If I am off the mark here, can anyone point me at any info explaining how it is implemented.
One example is found in the package 'wondershaper', part of SuSE Linux >= 9.1
See the manual or /usr/share/docs/packages/wondershaper for more info (no need to install this package if you browse it with mc).
I don't know if this is something for professional use.
This is a slightly different subject area.... Wondershaper is for QoS (from my understanding). A search through the files doesnt mention 95th percentile. Anyone else got any experience of this ? Whitey
On Sunday 31 October 2004 16:18, Neil White wrote:
Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers.
I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored.
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
I am just interested really - I dont have any experience with high end switches like the Summit. - Is it even possible to set a max bandiwdth on the switch's ports ?
If I am off the mark here, can anyone point me at any info explaining how it is implemented.
One example is found in the package 'wondershaper', part of SuSE Linux >= 9.1
See the manual or /usr/share/docs/packages/wondershaper for more info (no need to install this package if you browse it with mc).
I don't know if this is something for professional use.
This is a slightly different subject area....
Hmm, well, can you give me a pointer, so that I at least can learn of what you're talking about?
Wondershaper is for QoS (from my understanding).
Yes.
A search through the files doesnt mention 95th percentile.
I've never heard of that term before. But here is the origin of Wondershaper: http://www.lartc.org/wondershaper/ (lartc = Linux Advanced Routing & Traffic Control) Usefull perhaps? ;) Cheers, Leen
Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers.
I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored.
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
I am just interested really - I dont have any experience with high end switches like the Summit. - Is it even possible to set a max bandiwdth on the switch's ports ?
If I am off the mark here, can anyone point me at any info explaining how it is implemented.
One example is found in the package 'wondershaper', part of SuSE Linux >= 9.1
See the manual or /usr/share/docs/packages/wondershaper for more info (no need to install this package if you browse it with mc).
I don't know if this is something for professional use.
This is a slightly different subject area....
Hmm, well, can you give me a pointer, so that I at least can learn of what you're talking about?
I cant really explain it any better than as it is explained here: http://www.seanadams.com/95/ It is a common way that ISP's bill customers for bandwidth in Colocation environments.
Wondershaper is for QoS (from my understanding).
Yes.
A search through the files doesnt mention 95th percentile.
I've never heard of that term before.
But here is the origin of Wondershaper: http://www.lartc.org/wondershaper/
(lartc = Linux Advanced Routing & Traffic Control)
Usefull perhaps? ;)
Wondershaper is a fantastic script (I have looked into it before for ensuring ssh traffic doesnt lag under heavy network loads). I *think* that the way most people handle 95th percentile is by using SNMP to query a switch's ports every five minutes to take the actual bandwidth usage reading. However, I have never used high end switches, so my guess's as to how it works may not even be technically possible.... Has anyone on this list got experience of this kind of measurement ? Whitey
Neil wrote regarding '[SLE] OT: Calculating 95th Percentile' on Sun, Oct 31 at 05:46:
Sorry for the off topic post, but I cant think of anywhere else to ask about this. I have googled and failed to find any valid answers.
I understand the principle of 95th percentile for bandwidth charging, but I dont get how it is monitored.
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
Perhaps I'm looking at this in an overly simplistic light, but don't you just take the customer's bandwidth usage at samples of n minutes, and then bill them for the usage point at which 95% of their usage is below? In other words, make a chart, find the mean and standard deviation, and add 2 standard deviations to the mean usage. That'll get you the point at which 5% of the n-minute average samples are above and 95% of the n-minute samples are below. On the other hand, if you have 1MB/s that can burst to 2MB/s, only 5% of your traffic should be between 1MB/s and 2MB/s. Enforce that any way you want - allow full pipe usage for a few hours until 5% of the month's time is used, then bump down to 1MB/s, charge the customer if they use too much, allow passing 1 of every 20 packets that would otherwise be dropped by the rate limiter, etc. Maybe that helps. Maybe it doesn't... --Danny
<snip>
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
Perhaps I'm looking at this in an overly simplistic light, but don't you just take the customer's bandwidth usage at samples of n minutes, and then bill them for the usage point at which 95% of their usage is below? In other words, make a chart, find the mean and standard deviation, and add 2 standard deviations to the mean usage. That'll get you the point at which 5% of the n-minute average samples are above and 95% of the n-minute samples are below.
Yes, this is correct. However, the thing I am interested in, is HOW is this actually done ? I.e, is the reading taken via SNMP off the router / switch ? Is this even possible. I dont know what can and cant be done with the high end routers / switch. Also, would the providor set the router / switch to allow up to 2MB/s ? or if not, what is restricting me to up to 2MB/s ?
Neil wrote regarding 'Re: [SLE] OT: Calculating 95th Percentile' on Mon, Nov 01 at 11:21:
<snip>
Our bandwidth is provided through a Summit48 switch / router. We get given 1MB/s bursting to 2MB/s.
Is this achieved by configuring our port on the switch/router to have a max speed of 2MB/s ? then querying the switch/router every 5 minutes for the current throughput ?
Perhaps I'm looking at this in an overly simplistic light, but don't you just take the customer's bandwidth usage at samples of n minutes, and then bill them for the usage point at which 95% of their usage is below? In other words, make a chart, find the mean and standard deviation, and add 2 standard deviations to the mean usage. That'll get you the point at which 5% of the n-minute average samples are above and 95% of the n-minute samples are below.
Yes, this is correct. However, the thing I am interested in, is HOW is this actually done ? I.e, is the reading taken via SNMP off the router / switch ? Is this even possible. I dont know what can and cant be done with the high end routers / switch. Also, would the providor set the router / switch to allow up to 2MB/s ? or if not, what is restricting me to up to 2MB/s ?
You probably have a hard limit set at 2MB/s, and you're paying based on 1MB/s usage, on the assumption that 95% of the time, you'll be using less than 1MB/s. As far as getting the data, it varies. I usually take the 1-minute average - get the number of bytes transferred on a given port, wait a minute, get the number of bytes, subtract, and that's bytes/minute. Divide by 60 and I've got 1-minute average bytes/second. As far as what other providers do, I dunno. Some likely use other time periods, but the idea's the same. Either way, yes, you can get the reading via SNMP off of most managed switches. I'm using iptables rules to log traffic at one site, and I'm monitoring a switch with SNMP to keep track of some specific workstations' usage. I'd think that your upstream provider is probably doing the monitoring on their end, rather than with hardware at the client site, but your router can probably also collect the data. --Danny
participants (3)
-
Danny Sauer
-
Leendert Meyer
-
Neil White