EN-DC Layer 2 messages in Logfiles

If anybody can highlight which Layer 2 messages should appear in 5G logfiles in EN-DC and why?

As we know EN-DC all control is going through MCG, rest PDCP harq and other messages should be seen in Layer 2 when analysing a 5G logfile?

There is no PDCP Harq. Harq is implemented at MAC layer.
I think beam changes should be seen in Layer 2.
Also al MAC control elements.

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I believe in 5G PDCP can do retransmissions, during HO.


You mean when 5G base station is connected to 5G core network?

I can not recall if it is the same with NSA.

BUT FOR 5G SA, yes.

But restransmission is done by RLC layer, and AM do this job.

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Yes RLC does retrasmissions.
Harq retransmissions are also possible at MAC layer, there is no harq at PDCP layer.

For the initial question, PDCP, RLC and MAC.

Layer 3 RRC reconfiguration in Master LTE node gives the details of PDCP entity in 5G NR as shown below:
Here the PDCP bearer is split at MCG(LTE node) and then more than one RLC layer ie LTE RLC and 5G RLC is used for data transmission,

[5G-NR RRC_F40 Data] :
value RadioBearerConfig ::=
[5G-NR RRC_F40 Data] :
value RadioBearerConfig ::=
cnAssociation eps-BearerIdentity : 5,
drb-Identity 6,
discardTimer infinity,
pdcp-SN-SizeUL len18bits,
pdcp-SN-SizeDL len18bits,
headerCompression notUsed : NULL
cellGroup 0 ## means uses more than 1 RLC with MCG SPLIT:bulb:
ul-DataSplitThreshold infinity,
pdcp-Duplication FALSE
t-Reordering ms200
cipheringAlgorithm nea2
keyToUse secondary ## uses 5G NR also in lower layer
[5G-NR RRC_F40 Data] :