User guide

Understanding Canopy Networks March 2005
Through Software Release 6.1
Issue 1 Page 67 of 425
Canopy System User Guide
Table 16: Differences between software and hardware scheduling
Difference
Category Factor
Software
Scheduling
Hardware
Scheduling
Aggregate throughput, less
additional overhead
6.8 Mbps 14 Mbps
Throughput
ACK slots in downlink used
for data except when request
for uplink is present
No Yes
Number of frames required
for the scheduling process
5 1
Round-trip latency
1
≈ 20 ms ≈ 6 ms
Latency
AP broadcast the download
schedule
Yes No
Allocation for uplink high-
priority traffic on amount of
high-priority traffic
Static, based
on fixed
percentage
Dynamic, based
on amount of
high-priority
traffic
Allocation for downlink high-
priority traffic on amount of
high-priority traffic
Dynamic, based
on amount of
high-priority
traffic
Dynamic, based
on amount of
high-priority
traffic
High-priority
Channel
Order of transmission
1. Any high-priority
2. Any low-priority
1. CIR high-priority
2. CIR low-priority
3. Other high-priority
4. Other low-priority
Transmit
Frame
Spreading
Support for Transmit Frame
Spreading feature
In all releases In Release 7.0 and
later
CIR Capability None In all releases
NOTES:
1. For 2.4- and 5.n-GHz modules.
7.1.15 Settable AP Broadcast Repeat Count
In Release 4.2 and later releases, a settable parameter controls how many times, in
addition to the original broadcast, the AP repeats each broadcast. You can set this
parameter to achieve high reliability or high throughput, or a compromise between these,
based on the type and amount of traffic that the AP broadcasts. For a description of
conditions where each allowed setting can be best, see Broadcast Repeat Count on 191.