RLC Parameters in AM mode
1. POLL_SN:
It will hold the value of SN of AMD for which poll bit is set.
2. PDU_WITHOUT_POLL
Number of PDUs sent since the most recent poll bit transmitted.
3. BYTE_WITHOUT_POLL
Number of bytes since most recent poll bit transmitted
4. RETX_COUNT
Number of re-transmission count of PDU’s
5. AM_WINDOW 512
6. UM_WINDOW
5bit – value set to 16
10bit – value set to 512
RLC Timers
Below are the timers that will be configured by RRC
1. t-PollRetransmit
AM Tx RLC entity in order to retransmit a poll.
2. t-Reordering
THis timer is used by Rx entity of AM RLC and Rx UM RLC in order to detect loss of RLC PDU at lower layer. After dectecting PDU packet failure the Rx AM/UM will wait for this timer to expire to completely discard the PDU.
Only one t-Reordering can be running at a time.
3. t-StatusProhibit
It is used by the receiving side of an AM RLC entity in order to prohibit transmission of a STATUS PDU.
RLC Configurable parameters from RRC
1. maxRetxThreshold
Used by Tx entity to limit the number of retransmissions of an AMD PDU.
2. pollPDU
This is AM Tx entity to trigger poll for every pollPDU PDUs
3. pollByte
This is AM Tx entity to trigger poll for every pollByte bytes
4. sn-FieldLength
This parameter gives UM SN field size in bits.
Reference TS 36.322