--- /dev/null
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. SPDX-License-Identifier: CC-BY-4.0
+.. Copyright (C) 2019 AT&T
+
+
+
+
+Admission Control xAPP Overview
+================================
+
+The Admission Control (AC) xAPP repository contains open-source code for a prototype xAPP that
+can execute the full control loop to regulate the number of 5G connection requests at a gNodeB.
+
+The AC xAPP subscribes and listens for SgNB Addition Request X2AP messages. Upon
+receiving one, it makes a decision on whether to accept or reject the request based on a simple
+sliding window. If the decision is to accept the request, it sends an SgNB Addition Acknowledge, else
+it sends an SgNB Addition Reject message.
+
+The AC xAPP repository contains code to handle the E2 subscription process, encode/decode E2AP Indication/Control messages, X2AP SgNB Addition Request/Response
+and supports the A1-interface which can be used to send policies to configure the admission control behaviour.
+
+
+
+