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Live Projects in C/C++ Linux

NAS Protocol Stack Design in UE and MMERRC Stack design UE and eNB


  1. NAS- UE and MME

  1.1          EMM States Management

 1.2          EMM Registered and Deregistered state Management

 1.3          GUTI Reallocation

 1.4          Authentication

 1.5          Security Mode Control

 1.6          Identification

 1.7          EMM Information

 1.8          Attach and combined Attach

 1.9          Detach and Combines Detach

 1.10       Normal and Combines Registration

 1.11       Periodic Registration

  2.1          Service Request

 2.2          Paging NAS Procedure

 2.3          Transport of NAS Message

 2.4          Generic Transport of NAS Message

 3.Session Management - UE and MME

 Implement the functions to carry on a session. To carry on the session, implement the Bearer creation, modification and release of them. For every session, create a default bearer and few dedicated bearer with a given QoS. Manage from Start of the session till end of the call session.

 3.1          ESM States and State Management

 3.2          IP Address Allocation

 3.3          Default EPS Bearer Context Activation

 3.4          Dedicated EPS Bearer Context Activation

 3.5          EPS Bearer Context Modification

 3.6          EPS Bearer Context deactivation

 3.7          PDN Connectivity

 3.8          PDN Disconnect

 3.9          Bearer Resource Allocation

 3.10       Bearer Resource Modification

 3.11       ESM status Management

 4.SystemInfo Broadcasting – eNB and UE

 Implement the required System information (different variables and constants to be used by eNB and the UE’s in that eNB area) to be formed as various messages and transmitted. They should be transmitted in an organised way in right timing and resources which are conveyed to UEs.

 4.1          Broadcasting setup and Scheduling

 4.2          MIB, SIB1 and SI

 4.3          Management of Received System Information

 4.4          SI Change Indication and Updation

 5.Paging Transmission/Reception

 Implement Paging actions at MME and eNB when there is incoming call to a mobile and Mobile is registered. MME passes the paging to eNB and eNB passes these pagings at specific time when the UE is awake.

 UE needs to keep monitoring the paging at specific timing when it is awake. Keep calculating the PF and PO timing and keep checking if there is any paging for itself. If there is any, then receive and initiate call as per the paging.

 5.1          Paging Scheduling – PF & PO determination

 5.2          Paging in Connected Mode

 5.3          Paging Reception and forwarding

  6.Idle Mode Management – UE

 When a mobile is switched on it is in Idle mode. When UE is not connected, it is in IdleMode. It needs to remain attached to the network through the best cell. It keeps doing proper PLMN selection, Cell-Reselection, Apply power, quality, barrings and speed factors for evaluation of best cell selection.

  7.1          PLMN Selection

 7.2          Registration – Triggered and Periodic

 7.3          Cell-Reselection

 7.3.1      S-Criteria Evaluation

 7.3.2      Ranking Evaluation

 7.3.3      Speed Factor Adjustment

 7.4          Closed Service Group Management

 7.5          MBMS Broadcasting and Receptions

  7.MAC (Medium Access Controller)

 MAC is the interface between the PHY layer and the rest of L2 layer protocol. Implement the HARQ, Random Access and Multiplex-DeMultiplex the logical channel data through the transport channels. Apply the s=prioritization and Scheduling Algorithms.

  8.1          Random Access Procedure

 8.2          Random Access Resource Selection

 8.3          RA Preamble Determination

 8.4          RA Response reception

 8.5          Contention Resolution among many users

 8.6          Mobile Time Alignment

 8.7          Hybrid ARQ Algorithm

 8.8          (Dis)Assembly and (De)Mmultiplexing Module

 8.9          Buffer Status Reporting

 8.10       Power Headroom Reporting

 8.11       DRX – Discontinuous Transmission/Reception

 8.12       Paging, Broadcasting and MBMS Reception

 8.13       Logical Channel Priritization

  8.RLC Design

 Implement the ARQ algorithm with sliding window algorithms. Apply the retransmission rules when PDU’s missing or not acknowledged. Implement the Data Link Layer Error correction by retransmission.

  9.1          RLC UM Transmit/Receive

 9.2          RLC TM Transmit/Receive

 9.3          RLC AM ARQ Transmission

 9.4          RLC AM ARQ Reception

 9.5          Polling and Status transmission

 9.6          Ack/Nack and Retransmission Mechanism

 9.7          Sliding Window Algorith

 9.8          Assembly and Sequencing Algorithm

 9.PDCP Module

 Implement the Packet Data Convergence Protocol for each type of signalling or data bearer and give interface to the fixed network side of bearers. Implement Cyphering  and decyphering of data. Manage handover process data transmission relay from one eNB to other eNB.

 10.1       PDCP Create and Setup

 10.2       Cyphering Algorith

 10.3       Integrity Protection Algorithm

 10.4       Robust Header Compression Algorithms

 10.5       Hyper Frame Numering and Management

 10.6       Handover data protection Management

 10.RRC-Connection Establishment

 Implement the functionality what mobile needs to do when there is an incoming call or there is an outgoing call. Mobiles initiates the connection with the network and executes all requirements to setup the signalling and data connectivity to carry on communications. Setup L1, L2 and L3 connectivity entities.

 11.1       RRC Module Initialization

 11.2       RRC Connection Establishment

 11.3       Context Setup/Modify/Release

 11.4       Paging reception and Scheduling

 11.5       Connection Setup

 11.6       Connection Access Admission

 11.7       Connection Security Verification and Activation

 11.8       RRC Connection Reconfiguration

 11.9       Counter Check

 11.10    RRC Connection Re-establishment

 11.11    RRC Connection Release

 11.12    SRB/DRB Add/mod/delete

 11.13    Radio Link Failure Management

 11.14    CSG Proximity Indications and Management

 12. Measurements Reports and Logs

Mobile measures signal levels and quality in the measurement gaps as programmed by the eNB. Build an independent process which organises the measurement Objects, Measurement Reports with measurement-Ids. After understanding the measurement protocol, enhance with better algorithm and make efficient measurements.

When Mobile is Idle and there is no connection with network, it is instructed to log the measurement report. When it comes in contact with network it is supposed to transfer the logged measurements to network if asked. Implement the Logged Measurement functionality.

12.1       Measurement Configurations with Objects and Triggers

12.2       Measurement Report Triggering

12.3       Managing Measurement GAPs and collecting Measurements

12.4       A3 Measurement Filtering

12.5       Setting A1-A6 and B1-B2 Events

12.6       Logged Measurement Configuration and Logging