Directory Structure :
---------------------
1. l2/build/ : contains files required to compile the code
   a. common : contains individual module's makefile
   b. odu    : contains main makefile to generate an executable binary
   c. scripts: contains scripts for logging

2. l2/docs/  : contains README and other configuration files for building docs
	
2. l2/src/ : contains layer specific source code
   a. 5gnrmac  : MAC source code
   b. 5gnrrlc  : RLC source code
   c. cm       : common, environment and interface files
   d. cu_stub  : Stub code for CU
   e. du_app   : DU application and F1 code 
   f. mt       : wrapper functions over OS
   g. phy_stub : Stub code for Physical layer
   h. rlog     : logging module


Pre-requisite for Compilation :
-------------------------------
1. Linux 32-bit/64-bit machine
2. GCC version 4.6.3 and above
3. Install LKSCTP
   a. On Ubuntu : sudo apt-get install -y libsctp-dev
   b. On CentOS : yum install lksctp-tools-devel
4. Install PCAP:
   a. On ubuntu : sudo apt-get install -y libpcap-dev
   b. On CentOS : yum install libpcap-devel


How to Clean and Build:
-----------------------
1. Building ODU binary:
   a. Build folder
         cd l2/build/odu
   b. Building ODU binary
         make odu MACHINE=BIT64 MODE=FDD
   c. Cleaning ODU binary
         make clean_odu MACHINE=BIT64 MODE=FDD

2. Building CU Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building CU Stub binary
         make cu_stub NODE=TEST_STUB MACHINE=BIT64 MODE=FDD
   c. Cleaning CU Stub binary
         make clean_cu NODE=TEST_STUB MACHINE=BIT64 MODE=FDD

2. Building RIC Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building RIC Stub binary
         make ric_stub NODE=TEST_STUB MACHINE=BIT64 MODE=FDD
   c. Cleaning RIC Stub binary
         make clean_ric NODE=TEST_STUB MACHINE=BIT64 MODE=FDD

4. Cleaning ODU and CU Stub
      make clean_all MACHINE=BIT64 MODE=FDD

How to execute:
---------------
1. Assign virtual IP addresses as follows:
      ifconfig <interface name>:ODU "192.168.130.81"
      ifconfig <interface name>:CU_STUB "192.168.130.82"
      ifconfig <interface name>:RIC_STUB "192.168.130.80"

2. CU execution folder:
      cd l2/bin/cu_stub
     
3. Run CU Stub binary:
      ./cu_stub

4. RIC execution folder:
      cd l2/bin/ric_stub
     
5. Run RIC Stub binary:
      ./ric_stub

4. DU execution folder:
      cd l2/bin/odu
     
5. Run ODU binary:
      ./odu

PS: CU stub and RIC stub must be run (in no particular sequence) before ODU