+1. About the INF project
+************************
+
+This project is a reference implementation of O-Cloud infrastructure which is based on StarlingX, and it supports multi-OS.
+
+* Currently the following OS are supported:
+
+ * CentOS 7
+ * Yocto 2.7 (warrior)
+
+1.1 About the CentOS based implementaion
+----------------------------------------
+The project provde wrapper scripts to automate all the steps of `StarlingX Build Guide`_ to build out the reference platform as an installable ISO image.
+
+.. _`StarlingX Build Guide`: https://docs.starlingx.io/developer_resources/build_guide.html
+
+1.2 About the Yocto based implementation
+----------------------------------------
+
+The project provde wrapper scripts to pull all required Yocto/OE layers to build out the reference platform as an installable ISO image.
+
+To contribute on this project, basic knowledge of Yocto/OpenEmbedded is needed, please refer to the following docs if you want to learn about how to develop with Yocto/OpenEmbedded:
+
+- `Yocto dev manual`_
+- `OpenEmbedded wiki`_
+
+.. _`Yocto dev manual`: https://www.yoctoproject.org/docs/2.6.3/dev-manual/dev-manual.html
+.. _`OpenEmbedded wiki`: http://www.openembedded.org/wiki/Main_Page
+
+
+2. How to build the INF project
+*******************************
+
+2.1 How to build the CentOS based image
+---------------------------------------
+
+2.1.1 Prerequisite for CentOS build environment
++++++++++++++++++++++++++++++++++++++++++++++++
+TBD
+
+2.1.2 Use wrapper script build_inf_centos.sh to setup build the CentOS based image
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+::
+
+ # Get the wrapper script with either curl or wget
+ $ curl -o build_inf_centos.sh 'https://gerrit.o-ran-sc.org/r/gitweb?p=pti/rtp.git;a=blob_plain;f=scripts/build_inf_centos/build_inf_centos.sh;hb=HEAD'
+ $ wget -O build_inf_centos.sh 'https://gerrit.o-ran-sc.org/r/gitweb?p=pti/rtp.git;a=blob_plain;f=scripts/build_inf_centos/build_inf_centos.sh;hb=HEAD'
+
+ $ chmod +x build_inf_centos.sh
+ $ WORKSPACE=/path/to/workspace
+ $ ./build_inf_centos.sh -w ${WORKSPACE}
+
+If all go well, you will get the ISO image in:
+${WORKSPACE}/prj_output/inf-image-centos-all-x86-64.iso
+
+
+2.2 How to build the Yocto based image
+--------------------------------------
+
+2.2.1 Prerequisite for Yocto build environment
+++++++++++++++++++++++++++++++++++++++++++++++
+
+* Your host need to meet the requirements for Yocto, please refer to:
+
+ * `Compatible Linux Distribution`_
+ * `Supported Linux Distributions`_
+ * `Required Packages for the Build Host`_
+
+The recommended and tested host is Ubuntu 16.04/18.04 and CentOS 7.
+
+* To install the required packages for Ubuntu 16.04/18.04: