diff --git a/README.txt b/README.txt
index edd233830fb125cb581eeaf5092311fee5cfed16..aec938c0d341e147599279c7c3a315d1aee63fd3 100644
--- a/README.txt
+++ b/README.txt
@@ -9,26 +9,36 @@ Please see NOTICE.txt for third party software that is included in the sources.
 The OpenAirInterface (OAI) software is composed of the following parts: 
 
 openairinterface5g
-├── cmake_targets: build utilities to compile (simulation, emulation and real-time platforms), and generated build files
-├── common : some common OAI utilities, other tools can be found at openair2/UTILS
+├── ci-scripts: Meta-scripts used by the OSA CI process. Contains also configuration files used day-to-day by CI.
+├── cmake_targets: Build utilities to compile (simulation, emulation and real-time platforms), and generated build files
+├── common : Some common OAI utilities, other tools can be found at openair2/UTILS
+├── doc : Contains an up-to-date feature set list
 ├── LICENSE
-├── maketags : script to generate emacs tags
-├── openair1 : 3GPP LTE Rel-10 PHY layer + PHY RF simulation and a subset of Rel 12 Features.
-├── openair2 :3GPP LTE Rel-10 RLC/MAC/PDCP/RRC/X2AP implementation. 
+├── maketags : Script to generate emacs tags
+├── nfapi : Contains the NFAPI code. A local Readme file provides more details.
+├── openair1 : 3GPP LTE Rel-10/12 PHY layer + PHY RF simulation. A local Readme file provides more details.
+├── openair2 : 3GPP LTE Rel-10 RLC/MAC/PDCP/RRC/X2AP implementation. 
+    ├── COMMON
+    ├── DOCS
+    ├── ENB_APP
     ├── LAYER2/RLC/ with the following subdirectories: UM_v9.3.0, TM_v9.3.0, and AM_v9.3.0. 
-    ├── LAYER2/PDCP/PDCP_v10.1.0. 
-    ├── RRC/LITE
+    ├── LAYER2/PDCP/PDCP_v10.1.0.
+    ├── NETWORK_DRIVER
     ├── PHY_INTERFACE
+    ├── RRC/LITE
+    ├── UTIL
     ├── X2AP
-    ├── ENB_APP 
 ├── openair3: 3GPP LTE Rel10 for S1AP, NAS GTPV1-U for both ENB and UE.
+    ├── COMMON
+    ├── DOCS
     ├── GTPV1-U
-    ├── NAS 
+    ├── NAS
     ├── S1AP
     ├── SCTP
     ├── SECU
     ├── UDP
-└── targets: top level wrapper for unitary simulation for PHY channels, system-level emulation (eNB-UE with and without S1), and realtime eNB and UE and RRH GW.
+    ├── UTILS
+└── targets: Top-level wrappers for unitary simulation for PHY channels, system-level emulation (eNB-UE with and without S1), and realtime eNB and UE and RRH GW.
 
 
 RELEASE NOTES:
@@ -44,3 +54,10 @@ v0.6 -> RRH functionality, UE greatly improved, better TDD support,
         a lot of bugs fixed. WARNING: oaisim in PHY abstraction mode does not
         work, you need to use v0.5.2 for that.
 v0.6.1 -> Mostly bugfixes. This is the last version without NFAPI.
+v1.0.0 -> January 2019. This version first implements the architectural split described in doc/oai_lte_enb_func_split_arch.png picture.
+            Only FAPI, nFAPI and IF4.5 interfaces are implemented.
+            Repository tree structure prepares future integrations of features such as LTE-M, nbIOT or 5G-NR.
+            Preliminary X2 support has been implemented.
+            S1-flex has been introduced.
+            New tools: config library, telnet server, ...
+            A lot of bugfixes and a proper automated Continuous Integration process validates contributions.
diff --git a/doc/FEATURE_SET.md b/doc/FEATURE_SET.md
index 4309d50937be43f18ca2d6bbf1d88b82f165c60a..fef47d9c271aae7eaf53640715baa9a48fb2a972 100644
--- a/doc/FEATURE_SET.md
+++ b/doc/FEATURE_SET.md
@@ -8,7 +8,8 @@
    5. [eNB RRC Layer](#enb-rrc-layer)
    6. [eNB X2AP](#enb-x2ap)
    7. [eNB Advanced Features](#enb-advanced-features)
-2. [OpenAirInterface UE Feature Set](#openairinterface-ue-feature-set)
+2. [OpenAirInterface Functional Split](#openairinterface-functional-split)
+3. [OpenAirInterface UE Feature Set](#openairinterface-ue-feature-set)
    1.  [LTE UE PHY Layer](#lte-ue-phy-layer)
    2.  [LTE UE MAC Layer](#lte-ue-mac-layer)
    3.  [LTE UE RLC Layer](#lte-ue-rlc-layer)
@@ -128,6 +129,18 @@ The X2AP layer is based on **3GPP 36.423** v14.6.0 and implements the following
 
 **To be completed**
 
+# OpenAirInterface Functional Split #
+
+-  RCC: Radio-Cloud Center
+-  RAU: Radio-Access Unit
+-  RRU: Remote Radio-Unit
+
+![Functional Split Architecture](./oai_lte_enb_func_split_arch.png)
+
+-  IF4.5 / IF5 : similar to IEEE P1914.1
+-  FAPI (IF2)  : specified by Small Cell Forum (open-nFAPI implementation)
+-  IF1         : F1 in 3GPP Release 15 (not implemented yet)
+
 # OpenAirInterface UE Feature Set #
 
 ## LTE UE PHY Layer ##
diff --git a/doc/oai_lte_enb_func_split_arch.png b/doc/oai_lte_enb_func_split_arch.png
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