Merge pull request #219389 from w-azure/winona-no-leaf

Changed all leaf and most child references

Author: denrea

articles/iot-edge/about-iot-edge.md

@@ -50,7 +50,7 @@ The Azure IoT Edge runtime enables custom and cloud logic on IoT Edge devices. T
 * Maintains Azure IoT Edge security standards on the device.
 * Ensures that IoT Edge modules are always running.
 * Reports module health to the cloud for remote monitoring.
-* Manages communication between downstream leaf devices and an IoT Edge device, between modules on an IoT Edge device, and between an IoT Edge device and the cloud.
+* Manages communication between downstream devices and an IoT Edge device, between modules on an IoT Edge device, and between an IoT Edge device and the cloud.
 
 ![IoT Edge runtime sends insights and reporting to IoT Hub](./media/about-iot-edge/runtime.png)
 

articles/iot-edge/how-to-authenticate-downstream-device.md

@@ -1,6 +1,6 @@
 ---
 title: Authenticate downstream devices - Azure IoT Edge | Microsoft Docs
-description: How to authenticate downstream devices or leaf devices to IoT Hub, and route their connection through Azure IoT Edge gateway devices. 
+description: How to authenticate downstream devices to IoT Hub, and route their connection through Azure IoT Edge gateway devices. 
 author: PatAltimore
 
 ms.author: patricka
@@ -14,7 +14,10 @@ services: iot-edge
 
 [!INCLUDE [iot-edge-version-all-supported](../../includes/iot-edge-version-all-supported.md)]
 
-In a transparent gateway scenario, downstream devices (sometimes called leaf devices or child devices) need identities in IoT Hub like any other device. This article walks through the options for authenticating a downstream device to IoT Hub, and then demonstrates how to declare the gateway connection.
+In a transparent gateway scenario, downstream devices (sometimes called child devices) need identities in IoT Hub like any other device. This article walks through the options for authenticating a downstream device to IoT Hub, and then demonstrates how to declare the gateway connection. 
+
+>[!NOTE]
+>A downstream device emits data directly to the Internet or to gateway devices (IoT Edge-enabled or not). A child device can be a downstream device or a gateway device in a nested topology.
 
 There are three general steps to set up a successful transparent gateway connection. This article covers the second step:
 

articles/iot-edge/how-to-configure-api-proxy-module.md

@@ -18,12 +18,15 @@ monikerRange: ">=iotedge-2020-11"
 
 This article walks through the configuration options for the API proxy module, so you can customize the module to support your gateway hierarchy requirements.
 
-The API proxy module simplifies communication for IoT Edge devices when multiple services are deployed that all support HTTPS protocol and bind to port 443. This is especially relevant in hierarchical deployments of IoT Edge devices in ISA-95-based network-isolated architectures like those described in [Network isolate downstream devices](how-to-connect-downstream-iot-edge-device.md#network-isolate-downstream-devices) because the clients on the child devices can't connect directly to the cloud.
+The API proxy module simplifies communication for IoT Edge devices when multiple services are deployed that all support HTTPS protocol and bind to port 443. This is especially relevant in hierarchical deployments of IoT Edge devices in ISA-95-based network-isolated architectures like those described in [Network isolate downstream devices](how-to-connect-downstream-iot-edge-device.md#network-isolate-downstream-devices) because the clients on the downstream devices can't connect directly to the cloud.
 
-For example, to allow child IoT Edge devices to pull Docker images requires deploying a Docker registry module. To allow uploading blobs requires deploying an Azure Blob Storage module on the same IoT Edge device. Both these services use HTTPS for communication. The API proxy enables such deployments on an IoT Edge device. Instead of each service, the API proxy module binds to port 443 on the host device and routes the request to the correct service module running on that device per user-configurable rules. The individual services are still responsible for handling the requests, including authenticating and authorizing the clients.
+For example, to allow downstream IoT Edge devices to pull Docker images requires deploying a Docker registry module. To allow uploading blobs requires deploying an Azure Blob Storage module on the same IoT Edge device. Both these services use HTTPS for communication. The API proxy enables such deployments on an IoT Edge device. Instead of each service, the API proxy module binds to port 443 on the host device and routes the request to the correct service module running on that device per user-configurable rules. The individual services are still responsible for handling the requests, including authenticating and authorizing the clients.
 
 Without the API proxy, each service module would have to bind to a separate port on the host device, requiring a tedious and error-prone configuration change on each child device that connects to the parent IoT Edge device.
 
+>[!NOTE]
+>A downstream device emits data directly to the Internet or to gateway devices (IoT Edge-enabled or not). A child device can be a downstream device or a gateway device in a nested topology.
+
 ## Deploy the proxy module
 
 The API proxy module is available from the Microsoft Container Registry (MCR): `mcr.microsoft.com/azureiotedge-api-proxy:1.1`.

articles/iot-edge/how-to-connect-downstream-device.md

@@ -1,6 +1,6 @@
 ---
 title: Connect downstream devices - Azure IoT Edge | Microsoft Docs
-description: How to configure downstream or leaf devices to connect to Azure IoT Edge gateway devices. 
+description: How to configure downstream devices to connect to Azure IoT Edge gateway devices. 
 author: PatAltimore
 
 ms.author: patricka
@@ -20,8 +20,10 @@ This article provides instructions for establishing a trusted connection between
 There are three general steps to set up a successful transparent gateway connection. This article covers the third step:
 
 1. Configure the gateway device as a server so that downstream devices can connect to it securely. Set up the gateway to receive messages from downstream devices and route them to the proper destination. For those steps, see [Configure an IoT Edge device to act as a transparent gateway](how-to-create-transparent-gateway.md).
-2. Create a device identity for the downstream device so that it can authenticate with IoT Hub. Configure the downstream device to send messages through the gateway device. For those steps, see [Authenticate a downstream device to Azure IoT Hub](how-to-authenticate-downstream-device.md).
-3. **Connect the downstream device to the gateway device and start sending messages.**
+
+1. Create a device identity for the downstream device so that it can authenticate with IoT Hub. Configure the downstream device to send messages through the gateway device. For those steps, see [Authenticate a downstream device to Azure IoT Hub](how-to-authenticate-downstream-device.md).
+
+1. **Connect the downstream device to the gateway device and start sending messages.**
 
 This article discusses basic concepts for downstream device connections and guides you in setting up your downstream devices by:
 
@@ -31,6 +33,9 @@ This article discusses basic concepts for downstream device connections and guid
 
 In this article, the terms *gateway* and *IoT Edge gateway* refer to an IoT Edge device configured as a transparent gateway.
 
+>[!NOTE]
+>A downstream device emits data directly to the Internet or to gateway devices (IoT Edge-enabled or not). A child device can be a downstream device or a gateway device in a nested topology.
+
 ## Prerequisites
 
 * Have the root CA certificate file that was used to generate the device CA certificate in [Configure an IoT Edge device to act as a transparent gateway](how-to-create-transparent-gateway.md) available on your downstream device. Your downstream device uses this certificate to validate the identity of the gateway device. If you used the demo certificates, the root CA certificate is called **azure-iot-test-only.root.ca.cert.pem**.
@@ -218,10 +223,10 @@ The output of this command may be long, including information about all the cert
 
 ## Troubleshoot the gateway connection
 
-If your leaf device has intermittent connection to its gateway device, try the following steps for resolution.
+If your downstream device has intermittent connection to its gateway device, try the following steps for resolution.
 
 1. Is the gateway hostname in the connection string the same as the hostname value in the IoT Edge config file on the gateway device?
-2. Is the gateway hostname resolvable to an IP Address? You can resolve intermittent connections either by using DNS or by adding a host file entry on the leaf device.
+2. Is the gateway hostname resolvable to an IP Address? You can resolve intermittent connections either by using DNS or by adding a host file entry on the downstream device.
 3. Are communication ports open in your firewall? Communication based on the protocol used (MQTTS:8883/AMQPS:5671/HTTPS:433) must be possible between downstream device and the transparent IoT Edge.
 
 ## Next steps