Added introduction, architecture section

Updated license header on new files.

Change-Id: Ic44db303ab935099698f8c6547904802381fce5c
diff --git a/overview/3gpp-compliance-4g.rst b/overview/3gpp-compliance-4g.rst
index b9e1bfe..abdfa5b 100644
--- a/overview/3gpp-compliance-4g.rst
+++ b/overview/3gpp-compliance-4g.rst
@@ -1,3 +1,7 @@
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
 .. _4g-compliance:
 
 4G - 3GPP Release Compliance
diff --git a/overview/3gpp-compliance-5g.rst b/overview/3gpp-compliance-5g.rst
index 94fc629..c58adad 100644
--- a/overview/3gpp-compliance-5g.rst
+++ b/overview/3gpp-compliance-5g.rst
@@ -1,3 +1,7 @@
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
 .. _5g-compliance:
 
 5G - 3GPP Release Compliance
diff --git a/overview/architecture.rst b/overview/architecture.rst
index 450b00c..3182ce5 100644
--- a/overview/architecture.rst
+++ b/overview/architecture.rst
@@ -1,9 +1,55 @@
-Architecture
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
+SD-Core Architecture
 ====================
 
+    * SD-Core is a flexible, agile, scalable and configurable dual-mode 4G/5G core
+      network platform that builds upon and enhances ONF’s OMEC and free 5GC core
+      network platforms to support LTE, 5G NSA and 5G SA services.
+
+    * The SD-Core control plane provides the flexibility of simultaneous supports
+      for 5G standalone, 5G non-standalone and 4G/LTE deployments.
+
+    * SD-Core provides a rich set of APIs to Runtime Operation Control (ROC).
+
+        * Operators can use these APIs to provision the subscribers in the mobile core;
+        * Control runtime configuration of network functions
+        * Provide telemetry data to third party applications
+        * Third party applications can leverage telemetry data to create applications
+          for closed loop control.
+
+.. image:: ../_static/images/SD-Core-Architecture.png
+  :width: 700px
+
+Multiple Distributed User Planes
+--------------------------------
+
+SD-Core has three User Plane Functions (UPFs) designed to be deployed throughout
+the network edge. Each UPF is optimized to handle specific classes of application
+and take advantage of various hardware acceleration options. Deployments can
+intermix the UPF variants.
+
+    * P4-Based UPF optimized for private enterprise deployments, and providing fine-grained
+      visibility for verifiable performance and secure operations
+    * Containerized Dual-Core UPF optimized for private enterprise deployments, capable of
+      processing LTE and 5G traffic simultaneously
+    * Containerized Dual-Core UPF optimized for various MNO use cases, capable of processing
+      LTE and 5G traffic simultaneously
+
+
+SD-Core architecture is modular and apis are provided to manage connectivity service.
+
+    - Connectivity service is designed in such a way that it can be consumed easily and its
+      easy to configure. Please refer ``configuration section``. Configuration APIs are same
+      for 4G & 5G service.
+    - Metrics are exposed from SD-Core which helps network admins and application developers.
+    - Application filtering is supported to restrict the access to applications.
+
 Architecture Diagram showing SD-Core box
 ----------------------------------------
-- Diagram should show ROC interface, Prom interface, UPF interface, gNB/eNB interface
+- Diagram should show ROC interface, prometheus interface, UPF interface, gNB/eNB interface
 
 Architecture Diagram of SD-Core 4G block
 ----------------------------------------
diff --git a/overview/faq.rst b/overview/faq.rst
index 144696f..dd19249 100644
--- a/overview/faq.rst
+++ b/overview/faq.rst
@@ -1,2 +1,6 @@
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
 FAQs
 ====
diff --git a/overview/introduction.rst b/overview/introduction.rst
index 4f04c83..5c0ba52 100644
--- a/overview/introduction.rst
+++ b/overview/introduction.rst
@@ -1,5 +1,43 @@
-Introduction
+..
+   SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+   SPDX-License-Identifier: Apache-2.0
+
+SD-Core Introduction
 ====================
-* White paper link
-* Community wiki page or meeting details
-* Generic description of SD Core projects...
+
+The SD-Core™ project is a 4G/5G disaggregated mobile core optimized for public
+cloud deployment in concert with distributed edge clouds and is ideally suited
+for carrier and private enterprise 5G networks. It exposes standard 3GPP interfaces
+enabling use of SD-Core as a conventional mobile core. It is also available
+pre-integrated with an adapter (part of the Aether ROC subsystem) for those
+deploying it as a mobile core as-a-service solution.
+
+SD-Core is an integral component of Aether, ONF’s 5G Connected Edge platform for
+private mobile connectivity and edge cloud services. It can be rapidly deployed
+pre-integrated with Aether, as a standalone 5G/4G mobile core, or as control and
+dataplane (UPF) components integrated into custom designed solutions. This range
+of versatility makes the open source SD-Core platform ideally suited for the
+broadest range of use cases and deployment scenarios.
+
+SD-Core Overview
+----------------
+
+    - Ensure only authenticated mobile devices have network access
+    - Provides IP connectivity for data & voice services
+    - Ensures connectivity adheres to QoS and network slice policies
+    - Tracks user mobility to ensure uninterrupted service
+    - Tracks subscriber usage
+
+.. image:: ../_static/images/SD-Core-Overview.png
+  :width: 700px
+
+SD-Core is an Integral Part of Aether
+-------------------------------------
+
+    - SD-Core is an integral component of Aether, ONF’s 5G Connected Edge platform for
+      private mobile connectivity and edge cloud services.
+    - SD-Core provides the 4G/5G connectivity and the SD-Core control plane at the central
+      site controls multiple SD-Core user plane components running at each Aether Edge site.
+
+.. image:: ../_static/images/Sd-Core-Aether-Integral.jpg
+  :width: 700px