Real 5G capture shows RLC retransmissions with no packet losses reported

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A captured 5G NR attach session shows the radio link layer resending the same RLC packet twice, yet no status report names a missing packet. The analysis examines RLC acknowledged mode on both the signaling and data bearers, which are ciphered at the PDCP layer while RLC headers stay readable. Sequence numbers count SDUs rather than transmissions, and the poll bit is set according to buffer state, so signaling polls almost every PDU while the data bearer polls only at the end of a burst. Both retransmissions were timer-driven, occurring 44.9 ms after unanswered polls, a delay matching the default t-PollRetransmit value in TS 38.331 that the trace never configures. The walkthrough is published on EventHelix's website.

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