User's Manual Part 1

3: Detailed Description
APCD-LM043-8.0 (DRAFT C) 41
• Grade of Service (GOS) on page 43
• GOS Configuration Files on page 45
• Transmit Queue Limits on page 47
• Polling MAC Statistics on page 47
• Performance Modelling on page 47
• Atypical Applications on page 51
• Broadcast Applications on page 51
• Network Monitoring on page 52
• Voice Over IP (VoIP) on page 52
3.6.1 EUM States
The LMS4000 900 MHz Radio Network data transmission is based on a WaveRider’s
patented polling algorithm, which takes advantage of patterns found in typical Internet usage.
Based on the EUM’s subscribed grade of service and current traffic level, the Polling MAC
continuously adjusts the rate at which the EUM is polled. This process is illustrated in the EUM
State Diagram in Figure 25.
Figure 25 EUM State Diagram
When an EUM first powers up, it is in an unregistered state.
In the unregistered state, the EUM is not being polled and is therefore not passing traffic. As
outlined in EUM Registration on page 24, an unregistered EUM sends a registration_request
to the CCU. If the EUM is authorized in the CCU Authorization Table, it becomes registered/
disassociated.
inactive/
associated
active/
associated
unregistered
registered/
disassociated
Random access for
EUM or payload for
EUM arrives at CCU
Traffic in either
direction
No traffic for ~0.5s
EUM is
not polled
EUM is
polled
often
EUM is
polled less
often
N
o
t
r
a
f
f
i
c
f
o
r
~
2
s
P
o
w
e
r
u
p
EUM is
not polled
regRequest/regResponse
From any state:
- deregRequest
- extended period with no traffic (~12h)
* Parameters are derived from the GOS
configuration file, and vary with EUM
grade of service.