Burst Options Help?

Wondering if you can answer a quick question. I am new to the 450 and was wondering about the burst rate options. I will be offering a 5mb down and 1mb service but I want it to burst for a little bit prior to the sustain rate. Can you recommend up and down burst settings I can try out? My goal is to make pages load fast and short videos like youtube ect. load fast and be off the network sooner and also give netflix users a good stream boost. 

I was thinking the following

10000 burst down 

0 burst up (unless I should have a burst up? Unsure) 

5000 sustain rate down

1000 sustain rate up 

What do you think of the above settings? 

I was reading some posts about it and what I dont understand is after the 10mb burst how long does it take for the bucket to fill back up and the client can then burst again?

I am very open to suggestive settings. 


You have it pretty much right, one value that you'll want to set as well is the Downlink Burst Allocation. This is the size of the bucket, up to 2.5GB's (or 2500000 kbits in the UI), that's allowed to burst before the connection is throttled down to the sustained rate. Play around with it and see what you get.

This was confusing for me too at first. The burst allocation is the size of the bucket. The burst rate is how fast the bucket will be used. If you use all the burst allocation then it will drop back to the sustained rate. As a customer uses part of the total sustained bandwidth, or during periods of idle, the burst bucket will refill at the sustained rate minus the currently in use rate. Ex: if a customer is using 1 mbit out of 5 mbit sustained the remainder 4 mbit will refill the bucket until it reaches its maximum size. The next time customer clicks a webpage data will come in at the burst rate up to the limit they have refilled the bucket to at that point.

We found the problem with very high burst buckets is Netflix and other streams will settle on a higher quality stream then when burst is done will pixelate or buffer until it renegotiated at sustained speed. If traffic is more bursts like web pages or short videos a high burst bucket is fine but a smaller one will help if your traffic is streaming heavy.


Thanks, I see what you are saying about the netflix. What settings did you end up settling in at. I dont want the nexflix stream to come in at hd because of the burst and then buffer because the sustained rate cant hold the hd stream. 

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We went with 30 seconds worth. Good for faster page loads and quick downloads but not too long to cause major issues. Just multiply burst speed times 30 to get what your burst allocation should be for bucket size. Can play around with it a bit too for business users or non video watchers to increase burst since it is helpful in regular non sustained traffic situations.

Please do read the Max Burst whitepaper.  While it covers how MaxBurst works, it gives alot of information on the burst bucket theory and how it works.  With MaxBurst, there are two levels of throttling available, MaxBurst and MIR.  You can find the whitepaper here: