Comtech EF Data ROSS - Manual (Page 24)

ROSS MN/13070
5. Last the modem looks for demodulator lock following TEK enable and grant to burst
transmit from hub STDMA controller.
6. During the modem boot cycle ROSS is in the background trying to query the modem for
last set Satellite ID (service area). Once ROSS receives a valid response containing the
SAT_ID_NUMBER, a compare is applied to current location determining if a
configuration update is required.
7. If polled SAT_ID_NUMBER matches current location no change is necessary. If
different a new configuration file is push updating all communications parameters.
8. The TEK message now commences setting the transmit flag to enable mode.
9. The modem is now at home state waiting for TEK enable and hub grant to transmit
message.
10. During this time ROSS will send commands to the ACU updating the new pointing
location.
11. Special power controls can be applied to assure connectivity to the hub station during the
burst entry cycle. See STDMA Power Hunt.
12. After TX enable and burst grant the remote modem sends a request for registration to the
managing VMS. It must receive acknowledgment before transitioning through IP routing
table changes and dynamic switching to dSCPC mode. During this process all customer
data traffic is blocked and only allowing management traffic to pass. This prevents
possible customer switching requests from being lost during registration processing.
Note during the modem query the ROSS server is also polling the ACU for location status.
If the ACU has failed to respond during this initial sequence, ROSS will enter Parked
mode waiting for valid responses before changing states. Also during this process the
antennas tracking maybe inhibiting transmit until signal lock is established.
3.3.2 Modem Hot Initialization
All the same valid polling rules apply during hot initialization processing and are assumed to be
valid in the next sequencing.
1. During normal mode the modem operates under standard Vipersat control with only one
difference, the ROSS governs the transmit state. All standard dynamic switching, power
controls and communication recoveries apply.
2. If the vessel transitions into a new SA the ROSS server process the handoff sequence as
describe previously. However the modem is now in an operational state with all current
set value enabled.
3. As the ROSS unit processes handoff mode it pushes the new configuration file to the
modem via a UDP Steamload protocol.
4. The modem receives the file and checks the integrity before copying to FLASH and
processing.
5. The processing of the parameter file is accomplished on the fly inhibiting transmit before
execution. As the file parameters are processed through the internal menu engine each
value is modified/copied over. Once complete the Streamload process performs a firm
boot (execution time is in the ms) initializing all new values.
Comtech EF Data, Vipersat Products Page 24 of 87