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Umeda-san,
Thank you for staying up very late (or getting up very early) to present the slides on the call today. As I mentioned on the call, I think in the current proposal the OLT sends to the ONU too many unnecessary parameters.
OLT sends to the ONU 3x THn, OLT_Tx, and ONU_Tx25G, and the ONU is supposed to calculate its own thresholds as thn = THn + OLT_Tx - ONU_Tx25G.
Another concern is that a discovery GATE is always for a single SOA class (or single range), but in the current proposal it carries information about all the power classes all the time. It is not necessary and makes the protocol look cluttered and confusing.
I think the Discovery GATE should carry just two additional parameters: 1) ONU_RSSI_Min 2) ONU_RSSI_Max
Different GATE MPCPDUs would specify different ONU_RSSI_Min and ONU_RSSI_Max, based on acceptable SOA range for each discovery attempt.
An ONU will participate in a discovery attempt if its own RSSI is within the range ONU_RSSI_Min <= ONU_RSSI_measured < ONU_RSSI_Max
The OLT has all the information to calculate the ONU_RSSI_Min and ONU_RSSI_Max values for the Discovery GATE. Assume that for every SOA level setting, the OLT knows OLT_RSSI_Min and OLT_RSSI_Max that are acceptable for this SOA level (you called these parameters THx)
OLT_RSSI = ONU_TSSI – UL If ODN loss is not measured directly, it is estimated from the downstream loss as UL = DL = OLT_TSSI – ONU_RSSI
So, from above we get OLT_RSSI = ONU_TSSI – OLT_TSSI + ONU_RSSI Solving for ONU_RSSI, we get _ONU_RSSI_ = OLT_RSSI + ONU_TSSI – OLT_TSSI
As you suggested in your presentation, instead of OLT_TSSI and ONU_TSSI, we can use typical transmit power levels _ONU_RSSI_ = OLT_RSSI + ONU_Tx_typ – OLT_Tx_typ
If OLT intends to do the discovery for SOA gain class X, it knows its Rx power range for this gain level: OLT_RSSI_Min_x and OLT_RSSI_Max_x
Then, in the GATE message it announces these values: _ONU_RSSI_Min_x_ = OLT_RSSI_Min_x + ONU_Tx_typ – OLT_Tx_typ _ONU_RSSI_Max_x_ = OLT_RSSI_Max_x + ONU_Tx_typ – OLT_Tx_typ
Even if UL and DL are different and the difference is known, still the OLT can add the correction factor to the same calculation.
Thank you, -Glen
From: Daisuke Umeda [mailto:umeda@xxxxxxxxx]
Dear all:
-- Daisuke Umeda Sumitomo Electric Industries, Ltd. 1-1-3, Shimaya, Konohana-ku, Osaka 554-0024, Japan To unsubscribe from the STDS-802-3-NGEPON list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGEPON&A=1 To unsubscribe from the STDS-802-3-NGEPON list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGEPON&A=1 |