Page 849 - 5G Basics - Core Network Aspects

Transport aspects 2

Table 11-48.1 – L2 link state transition command (FTU-O to FTU-R)

Length
Name Byte Content
(Bytes)
3 [0000 000a]
a = Link state transition type:
- a = 0: from L2.2 to L2.1N.
- a = 1: from L2.2 to L2.1B.
L2.1-Transition- 3 2 0516 (Note 1)
Request
3 [0000 000a]
a = Link state transition type:
- a = 0: from L2.1B to L2.1N.
- a = 1: from L2.1N to L2.1B.
NOTE 1 – All other values are reserved by ITU-T.
NOTE 2 – The superframe in which RMC is placed shall be as defined in clause 13.4.2.1.
NOTE 3 – The L2.1_B DR_min and L2.2_B DR_min proposed by the FTU-O determine the minimum DTU payload rate necessary to
accommodate both the required user data and the eoc (see clause 13.4.4). The values shall take into account the MIB settings of
L2.1_ETR_min, L2.2_ETR_min, and L2.1_NDR_max, L2.2_NDR_max, and the overhead bit rate required to support downstream
eoc during L2.1 and further in L2.2.
NOTE 4 – The FTU-O may propose a bit loading reduction on some frequencies to facilitate higher SNRM during the L2.2 link
state compared to the bit loading used during the L2.1 link state.

Table 11-48.2 – L2.1/L2.2 upstream transmission parameters

Byte Content

1 One byte for Q
2 One byte for KFEC
3 One byte for RFEC
4 [0000 aaaa]
aaaa = upstream configuration change count (SCCC) (Note 2)
5 and 6 Two bytes for the start subcarrier index (Note 1)
7 and 8 Two bytes for the stop subcarrier index (Note 1)
Variable Data subcarrier parameter block
A variable number of bytes describing the subcarrier parameter field for each
subcarrier (Note 3)
NOTE 1 – Subcarriers outside this set shall be unused in L2.1, by setting b i = 0, g i = 0. The subcarrier set in L2.2 shall be the same
as in L2.1.
NOTE 2 – The value of the SCCC shall be incremented relative to the last upstream SCCC value prior to any link state transition.
NOTE 3 – The formatting of the data subcarrier parameter field and the valid range of the values shall be the same as those
specified for OLR type 1 (see clause 11.2.2.5, Table 11-10 and Table 11-11)

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