GE ApexPro Service Manual page 32

Tower/Receiver Determination
2-16
Equipment Overview: Theory of Operation
11. Tower/receiver determination is comprised of either CDT-LAN or ApexPro
admissions:
CDT–LAN Admissions
When the master tower determines the admit request is a CDT-LAN telemetry type,
it searches the RWHAT database (See
offering the ADMIT service. The conditions used to pick a receiver are (in
descending priority):
1. Discharged receiver with the same unit name as is contained in the admit
packet.
2. Discharged universal receiver (unit name "mei").
If neither conditions are true, an admit failure response is sent back to the initiating
device, indicating that no CDT–LAN receivers are available.
If either condition is true, the admit request is forwarded to the appropriate receiver.
ApexPro Admissions
When the master tower determines the admit request is an ApexPro telemetry type,
it searches the RWHAT database (See
towers with available receivers.
RWHAT data contains the following information about ApexPro towers and their
receivers:
The units a tower can accept admits from
The number of receivers a tower has reserved for specific units
The units a tower can accept admits from (to unassigned receivers)
Additionally, if no unit names are entered for a tower (i.e., the tower accepts admits
for any unit), the receivers are classified as universal receivers (unit name "mei").
This list has no individual receiver information in it — a unit's presence in the list
only indicates that at least one receiver in the unit is available on the ApexPro tower.
The following priority conditions are used to determine which ApexPro tower
should receive the forwarded admit request (in descending priority):
a. A tower that has a receiver reserved for the unit name in the admit packet.
b. A tower that has a receiver available for the unit name in the admit packet,
but not reserved. (This indicates that all receivers assigned to the unit are
admitted, that the unit is configured to use unassigned receivers, and that an
unassigned receiver is still available.)
c. A tower that has a universal receiver available (unit name "mei").
If none of these conditions are true, an admit failure response is sent back to the
initiating device, indicating that no ApexPro receivers are available.
If any of the conditions are true, the admit request is forwarded to the appropriate
tower.
ApexPro Telemetry Server
2001989-178
"RWHAT Data" on page 2-12) for a receiver
"RWHAT Data" on page 2-12) for ApexPro
Revision C