QOS settings for 900 SM (Newbie)

I have read a bunch of stuff about QOS settings on the 900Mhz SM but I think I am now more confused than ever. Is there a good standard to go by for these settings, especially the broadcast/multicast data rate.
Here is one of our customer set-ups, what should be changed and why?

Thanks for all your help
CMack

Sustained Uplink Data Rate :100 (kbps) (Range: 0-- 40000 kbps)
Sustained Downlink Data Rate :185 (kbps) (Range: 0-- 40000 kbps)
Uplink Burst Allocation :100 (kbits) (Range: 0 – 500000 kbits)
Downlink Burst Allocation :185 (kbits) (Range: 0 – 500000 kbits)
Enable Broadcast/ Multicast Data Rate : Disabled
Broadcast/ Multicast Uplink Data Rate :N/A (kbps) (Range: 1-- 40000 kbps)
CIR Bandwidth Settings
Low Priority Uplink CIR :100 (kbps) (Range: 0 – 20000 kbps)
Low Priority Downlink CIR :185 (kbps) (Range: 0 – 20000 kbps)
Hi Priority Channel : Disabled

There isn’t a single “right” answer to this question - it all depends on your user base and your desired service tiers.

What these settings mean:

Sustained uplink: the sustained (think long transfers) rate of your SM’s send. This is in kbps.

Sustained downlink: sustained rate of your SM’s receive. Also in kbps.

Uplink burst: Think of this as a “turbo” mode. What it is is a file size, measured in kbits. The SM can upload at the maximum air rate it is capable of (air rate, not the sustained rate from above) until this file limit has been reached. Once this file size has been reached, the SM will slow its upload rate to the sustained rate you listed. When the SM stops transmitting, the burst allocation will slowly rebuild itself at the sustained rate until it reaches the file size you specified. There’s a “token bucket” analogy out there that helps explain this really well, but I do not know it off the top of my head so I’ll leave it for someone else to post.

Downlink burst: Same as uplink burst only on the receive side of the SM.

Broadcast/Multicast rate: rate at which your SM can send out broadcast traffic. Some broadcast traffic is required for proper operation of TCP/IP, so you do not want to set this too low. Our network uses DHCP and I have my SMs set at about 10kbps without issues. People using PPPoE I’ve heard have gone as low as 5kbps.

The CIR settings are for guaranteeing bandwidth to customers. I’d leave these alone unless you are offering VoIP to your customers, at which time you’d want to adjust your Hi Priority settings to guarantee a certain amount of bandwidth for phone service.

Thanks very much, that sheds some light for me.