5G NR WIRELESS RLC Layer Design 3gpp Spec No -(38.322)

Wishlist Share
Share Course
Page Link
Share On Social Media

About Course

The Radio Link Control (RLC) layer in 5G NR (New Radio), as defined by 3GPP TS 38.322, operates at Layer 2 (L2) of the OSI model and is responsible for data transfer, segmentation, reassembly, error correction, and in-sequence delivery between the User Equipment (UE) and gNB (gNodeB).

What Will You Learn?

  • You will have easy access to comprehensive knowledge of both fundamental and advanced aspects of 5G-NR specially RLC Protocol
  • Upon completion of the course, your understanding and imagination of the technology will be significantly enhanced.
  • Upon completion of the course, you will have cultivated critical thinking and debugging skills that will enable you to effectively analyze and troubleshoot.

Course Content

Compare LTE, RLC and 5G RLC
The Radio Link Control (RLC) layer plays a pivotal role in both LTE (Long-Term Evolution) and 5G NR (New Radio) networks by ensuring reliable data transfer over the radio interface. While the fundamental functions of the RLC layer remain consistent across these technologies, there are notable differences in their design and operation. Similarities: Modes of Operation: Both LTE and 5G NR RLC support three primary modes: Transparent Mode (TM): No RLC header is added; used for control signaling with minimal overhead. Unacknowledged Mode (UM): Adds an RLC header; suitable for real-time data where occasional loss is acceptable. Acknowledged Mode (AM): Incorporates an RLC header and employs Automatic Repeat reQuest (ARQ) for reliable data transfer. Core Functions: In both LTE and 5G NR, the RLC layer is responsible for: Segmentation and Reassembly: Dividing large Service Data Units (SDUs) into smaller Protocol Data Units (PDUs) for transmission and reassembling them at the receiver. Error Correction: Utilizing ARQ mechanisms in AM mode to ensure data integrity through retransmissions. Reordering and Duplicate Detection: Ensuring PDUs are delivered in sequence and identifying any duplicate transmissions.

  • lesson-1
  • lesson-2
  • lesson-3

5G—RLC Architecture
In 5G New Radio (NR), the Radio Link Control (RLC) layer is a pivotal component of the Layer 2 protocol stack, positioned between the Packet Data Convergence Protocol (PDCP) and Medium Access Control (MAC) layers. It is responsible for ensuring reliable data transfer over the radio interface by performing functions such as segmentation, reassembly, error correction, and duplicate detection.

RLC modes – TM, UM, AM
In 5G New Radio (NR), the Radio Link Control (RLC) layer operates in three distinct modes, each tailored to specific data transmission requirements:

5G –RLC service
The Radio Link Control (RLC) layer in 5G New Radio (NR) is a critical component of the Layer 2 protocol stack, positioned between the Packet Data Convergence Protocol (PDCP) and Medium Access Control (MAC) layers. Its primary role is to facilitate reliable data transfer over the radio interface by performing several essential functions:

5G –RLC function
The Radio Link Control (RLC) layer in 5G New Radio (NR) is a crucial component of the Layer 2 protocol stack, positioned between the Packet Data Convergence Protocol (PDCP) and Medium Access Control (MAC) layers. Its primary role is to ensure reliable data transmission over the radio interface by performing several key functions:

5G RLC Entity Handling – establishment/Re- establishment/Release
in 5G networks, the Radio Link Control (RLC) entity plays a vital role in handling data transmission between the User Equipment (UE) and the gNodeB (5G base station). It is responsible for ensuring reliable data delivery, flow control, and error correction in the radio access network. Below is an overview of the key processes involved in the establishment, re-establishment, and release of the RLC

5G RLC Procedures
In 5G, the Radio Link Control (RLC) layer is responsible for the reliable transmission of data between the User Equipment (UE) and the gNodeB (5G base station), which involves procedures related to data transfer, reliability, flow control, and error correction. RLC operates at the Layer 2 of the protocol stack and supports three main modes: Acknowledged Mode (AM) Unacknowledged Mode (UM) Transparent Mode (TM)

Data transfer Procedure
The Data Transfer Procedure in the RLC (Radio Link Control) layer is a crucial process that manages the transmission and reception of data between the User Equipment (UE) and the gNodeB (5G base station). The RLC ensures that data is delivered reliably, efficiently, and in the correct order, with mechanisms for error detection, flow control, and retransmissions (in Acknowledged Mode (AM)).

ARQ Procedure
The ARQ (Automatic Repeat reQuest) procedure is a fundamental part of reliable data transmission in networks, including 5G, and is primarily implemented in the RLC (Radio Link Control) layer in Acknowledged Mode (AM). The ARQ procedure ensures that data is reliably transmitted by enabling the detection and retransmission of lost or corrupted data. In 5G, the ARQ procedure is specifically important for the AM mode of RLC and focuses on ensuring data integrity by requesting retransmissions when packets are lost or errors are detected.

SDU Discard procedure
The SDU Discard Procedure in the context of 5G networks, specifically at the RLC (Radio Link Control) layer, is responsible for handling situations where the Service Data Units (SDUs) need to be discarded due to certain conditions such as buffer overflow, data loss, or reordering delays. The SDU Discard Procedure ensures that the RLC layer operates efficiently, by discarding data that is no longer needed or relevant, particularly when it cannot be delivered to the upper layers (such as PDCP, SDAP, etc.) in a timely manner. The procedure helps to manage resources and maintain system performance, especially in cases where transmission delays, out-of-sequence data, or congestion occur.

Retransmission, Polling
Both retransmission and polling are important mechanisms in the RLC (Radio Link Control) layer, specifically in Acknowledged Mode (AM), to ensure reliable data transmission. These procedures contribute to maintaining data integrity and ensure that lost or corrupted data is retransmitted efficiently. Let's break down each of these concepts:

Status Reporting
status Reporting is a crucial mechanism in the RLC (Radio Link Control) layer that enables efficient and reliable data transmission, particularly in the Acknowledged Mode (AM). It allows the receiver to communicate the reception status of Protocol Data Units (PDUs) to the sender. This information helps the sender decide whether retransmission is necessary or if the transmission is proceeding correctly.

Reestablishment Procedure
he RLC Re-establishment Procedure is an important mechanism in 5G RLC (Radio Link Control) designed to restore the state of the RLC entity after a failure or disruption in the communication link. This is necessary in cases where an RLC connection is lost due to network issues such as channel failures, handovers, or temporary disruptions. The re-establishment procedure allows the RLC to re-sync and resume reliable data transmission without starting from scratch. This procedure is defined within 3GPP (Third Generation Partnership Project) standards to ensure continuity in services, maintaining data integrity and minimizing data loss.

Segmentation, Reordering
In 5G Radio Link Control (RLC), segmentation and reordering are important mechanisms used to manage the transmission of Service Data Units (SDUs) over the radio link. These procedures are essential for ensuring that data is reliably delivered, efficiently transmitted, and correctly reconstructed at the receiving end

5G-RLC protocol data Unit
n the context of 5G RLC (Radio Link Control), the Protocol Data Unit (PDU) is the fundamental unit of data exchange between the RLC layer and the lower layers (like MAC). The RLC PDU contains the information that is transmitted over the air interface between the User Equipment (UE) and the base station (e.g., gNB in 5G). It is essential for the transmission and management of data in different modes (e.g., AM (Acknowledged Mode), UM (Unacknowledged Mode), and TM (Transparent Mode)).

5G RLC Formats and Parameter
The 5G RLC (Radio Link Control) layer is responsible for ensuring the reliable transmission of data between the User Equipment (UE) and the gNB (Next Generation Node B) in 5G networks. The RLC format refers to the specific structure of the RLC PDU (Protocol Data Unit) and the fields within it, while the parameters define the behavior and characteristics of the RLC layer in various modes such as AM (Acknowledged Mode), UM (Unacknowledged Mode), and TM (Transparent Mode). In this section, we will discuss the key RLC formats and important parameters that govern their operation in 5G.

Student Ratings & Reviews

No Review Yet
No Review Yet
Scroll to Top