User's Manual
Chapter 7: Configuration
Configuring quality of service
Page 7-189
Configuring quality of service
Maximum Information Rate (MIR) Parameters
Point-to-multipoint links use the following MIR parameters for bandwidth management:
Sustained Uplink Data Rate (kbps)
Uplink Burst Allocation (kb)
Sustained Downlink Data Rate (kbps)
Downlink Burst Allocation (kb)
Max Burst Downlink Data Rate (kbps)
Max Burst Uplink Data Rate (kbps)
Set each of these parameters per AP or per SM independently.
Note
You can refer below whitepaper for 450 Platform Family Max Burst MIR:
http://www.cambiumnetworks.com/resources/pmp-450-maxburst/
Token Bucket Algorithm
The software uses a token bucket algorithm that has the following features:
Stores credits (tokens) for the SM to spend on bandwidth for reception or transmission.
Drains tokens during reception or transmission.
Refills with tokens at the sustained rate set by the network operator.
For each token, the SM can send toward the network in the uplink (or the AP can send toward the
SM in the downlink) an equivalent number of kilobits. Two buckets determine the permitted
throughput: one in the SM for uplink and one in the AP for downlink.
The applicable set of Uplink Burst Allocation and Downlink Burst Allocation parameters determine
the number of tokens that can fill each bucket. When the SM transmits (or the AP transmits) a
packet, the equivalent number of tokens is removed from the uplink (or downlink) bucket.
Except when full, the bucket is continuously being refilled with tokens at rates that the applicable
set of Sustained Uplink Data Rate and Sustained Downlink Data Rate parameters specify. The
bucket often drains at a rate that is much faster than the sustained data rate but can refill at only
the sustained data rate. Thus, the effects of the allocation and rate parameters on packet delay are
as follows:
The burst allocation affects how many kilobits are processed before packet delay is imposed.
The sustained data rate affects the packet delay that is imposed.