hello,
i want some help in burst limit I have read this http://wiki.mikrotik.com/wiki/Manual:Queues_-_Burst and a lot of others
and I can’t undestand how it wok
basiclly i want this i have set limit-at=1M/2M max-limit=1M/2M
now i want to add burst so if any one was under the limit (1M/2M) and start downloading he can get 2M/4M speed for 15s
so what i should do?
regards
Mikrotik Bursting does not quite work in the method you desire.
It samples the average bandwidth of the last 16 samples (i.e. if your burst time is set to 16 seconds, the samples would be taken every 1 second, if it was 8 minutes, the samples would be every 30 seconds). If, during or after 16 samples, the average throughput is below the burst-threshold then the client will be allowed up to burst-limit. If the samples exceed the limit-at setting, then the client will be limited to max-limit setting. What this means is that a user bursting to 4Mbps would be limited to a 2Mbps max-limit quicker than another customer through the same queue who might only be moving 3Mbps (remember that throughput is also limited by the server they are downloading data from).
The idea of limiting burst to a fixed 15s could only be achieved through the use of scripts that toggle the max-limit alone rather than relying on bursting. If scripting, you would also need to consider what would reset that 15s counter, is it per connection, per file, per hour, etc?
This is of course exactly what is described in the link you already followed. I think you might find it easier to follow the constraints of bursting than to re-engineer it through scripting.
I found that 30 second to 1 minute samples (8 to 16 minute burst-time) with a burst-limit at double the max-limit (just what you proposed) worked nicely under real life conditions. Fifteen seconds is a small enough amount of time that I doubt anyone would notice the benefits as it’s only an additional 3.75MB of data over the default rate. ((4Mbps-2Mbps)*15s = 3.75MB) A user can hit 3.75MB with one email attachment or a single webpage.
If you want them to be limited to the lower rate until they are idle long enough to drop the average, set the burst-threshold to the same as the max-limit (half of the burst-limit. In that scenario, someone who was streaming data at the max-limit could only burst over the burst-threshold for the burst-time but would then forever be limited to the max-limit until their streaming stopped. If instead, you wanted it to burst periodically, the burst-threshold would need to be higher than the max-limit so their average would drop below the threshold without having to stop their stream.
I hope this helps.