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SI - Stall Indicator

The Stall indicator bit indicates whether the mobile’s RLC (Radio Link Control) transmit window can advance (i.e., is not stalled) or can not advance (i.e., is stalled). The MS (Mobile Station) shall set the SI bit in all uplink RLC data blocks.


  • Fully interactive 3GPP based network map
  • Narrated call flows
  • Detailed network procedures

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