added design section and deployment for cloud native smf amf
Change-Id: I8daa75db0ceb8de3e26f203837c38c6abd1ba9b9
diff --git a/design/design-amf.rst b/design/design-amf.rst
new file mode 100644
index 0000000..8359abc
--- /dev/null
+++ b/design/design-amf.rst
@@ -0,0 +1,26 @@
+..
+ SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+ SPDX-License-Identifier: Apache-2.0
+
+.. _design_amf:
+
+AMF Design Overview
+===================
+
+.. image:: ../_static/images/CN-AMF.png
+ :width: 500px
+
+SctpLb (SctpLoadbalancer)
+-------------------------
+
+ * Accept and manage gnb or sctp connections
+
+ * GRPC communication between SctpLb and Amf Service
+
+ * Handles Amf Instance Down/Up Notifications
+
+ * Backend NF manages AMF instances
+
+ * Round-Robin Distribution of Sctp Messages over grpc channel to Backend NF
+
+ * Redirect Support for forwarding to a particular Amf Instance
diff --git a/design/design-smf.rst b/design/design-smf.rst
new file mode 100644
index 0000000..2b93438
--- /dev/null
+++ b/design/design-smf.rst
@@ -0,0 +1,26 @@
+..
+ SPDX-FileCopyrightText: © 2020 Open Networking Foundation <support@opennetworking.org>
+ SPDX-License-Identifier: Apache-2.0
+
+.. _design_smf:
+
+SMF Design Overview
+===================
+
+.. image:: ../_static/images/CN-SMF.png
+ :width: 500px
+
+UPF-Adapter
+-----------
+
+As UPF may not support connections from multiple SMF instances with same Node-Id,
+UPF-Adapter layer has been introduced.
+
+* UPF-Adapter acts like Mux-Demux for PFCP messages between multiple SMF instances and UPF.
+
+* SMF sends custom PFCP msg to UPF-Adapter if UPF-Adapter is deployed.
+
+* The UPF-Adapter intercepts and modifies certain fields before sending PFCP msg to actual UPF.
+
+* Similar handling is done for the response from UPF towards SMF.
+