Hey folks, does anyone have any suggestions as to what these should be set for? Does everyone use the defualts?
Sustained Uplink Data Rate (kbps) (Range: 0–20,000 kbps)
Uplink Burst Allocation (kbits) (Range: 0–500,000kbits)
Sustained Downlink Data Rate (kbps) (Range: 0–20,000 kbps)
Downlink Burst Allocation (kbits) (Range: 0–500,000kbits)
Should the AP be the same as the SM’s?
I was just wondering, and thinking that maybe I should keep thsoe at only 2mb? (unless they work different than they sound.
Any pointers or expainations would be greatly appreciated. The manual was very quick topic.
Thanks!
Quick bit bucket analogy:
Size of bucket = Burst allocation
Refill rate of bucket = Sustained rate
You pull the cork on the bottom of the full bucket (rate of drain is the available bandwith between AP and SM if you set burst allocation greater than 0) and start refilling at the same time. Eventually the level in the bucket drops and your drain rate will drop off to the refill rate as long as the cork is out.
If you set the burst to 0, the max rate they will ever get is the sustained rate (no bucket at all).
I have all my customers set to 1500 down / 500 up with bursts of 10000 and 5000. This gives them enough burst so that they get their first 1-2M at speeds greater than the sustained rates, but on an extended transfer it will eventually cut them back to the sustained rate setting.
You can see the effect on bandwidth speed tests, eg speakeasy.net/speedtest. With a sustained rate setting of 1500 and burst at 10000 I get test results ranging from 2500 to 3500kb (impress your customers). But I always point out to the customer that on an extended transfer it will drop off to the sustained setting.
The settings you choose depend on the level of service you want to offer. By giving them a reasonable burst, web pages, mid-size emails will be zippier but that 200M download will be at the sustained rate.
As far as the AP settings, I leave those at the max.
Good Analogy.
For a long time, we did not use bursting, we just set the radio sustained rate at the subscribed speed and set burst to 0. As we started to approach 10Mbps sustained traffic I decided to test the bursting. I cut all users sustained speed in half and added burst allocations.
SOHO - 750/375 sustained, 1500/750 burst
2000 - 1000/1000 sustained, 2000/2000 burst
3000 - 1500/1500 sustained, 3000/3000 burst
Not one customer noticed.
I believe that this is why:
- low latency
- 0 errors on all devices across the network
- virtually zero multicast
- router running at 40-50% at peak
- main BH running at 25%
- VoIP is stable, not choppy
When browsing, pages load fast, Exchange and Lotus loads quickly, VPN’s are responsive, etc.
Our 2.4GHz and 5.7GHz SM’s get 3500k x 3200k link tests. So as George explained, the SOHO customer will see the 1500kb of data transferred at 3500kbps. Once the 1500kbps is used up, the transfer rate will drop to 750kbps. The 2000 customer will see 2000kb at 3500k and then drop to 1000kbps, and the 3000 customer will see 3000kb at 3500k then drop to 1500k.
My Multiple Tenant sites are set to 3000/3000 sustained with no burst.
And the same holds true if you are using BAM as far as burst settings and what not to configure rate plans… Correct?
I don’t use BAM, but I would assume that it changes the settings in the radio. Check the GUI in the SM to verify that the changes were made. You want these rates to be in effect at the SM to keep from flooding your infrastructure.