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samples/README.md

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+# Sample Applications for the AWS IoT Device SDK v2 for Python
+This directory contains sample applications for [aws-iot-device-sdk-python-v2](../README.md).
+
+### Table of Contents
+* [Samples](#samples)
+    * [MQTT5 Client Samples](#mqtt5-client-samples)
+    * [Service Client Samples](#service-client-samples)
+    * [Greengrass Samples](#greengrass-samples)
+* [Instructions](#instructions)
+* [Sample Help](#sample-help)
+* [Enable Logging](#enable-logging)
+
+
+## Samples
+### MQTT5 Client Samples
+##### MQTT5 is the recommended MQTT Client. Additional infomration and usage instructions can be found in the [MQTT5 User Guide](../documents/MQTT5_Userguide.md). The samples below will create an MQTT5 client, connect using the selected method, subscribe to a topic, publish to the topic, and then disconnect.
+| MQTT5 Client Sample | Description |
+|--------|-------------|
+| [X509-based mutual TLS](./mqtt/mqtt5_x509.md) | Demonstrates connecting to AWS IoT Core using X.509 certificates and private keys.
+| [Websockets with Sigv4 authentication](./mqtt/mqtt5_aws_websocket.md) | Shows how to authenticate over websockets using AWS Signature Version 4 credentials. |
+| [AWS Custom Authorizer Lambda Function](./mqtt/mqtt5_custom_auth.md) | Examples of connecting with a signed and unsigned Lambda-backed custom authorizer.
+| [PKCS11](./mqtt/mqtt5_pkcs11_connect.md) | Demonstrates connecting using a hardware security module (HSM) or smartcard with PKCS#11. |
+| [Other Connection Methods](../documents/MQTT5_Userguide.md#how-to-create-an-mqtt5-client-based-on-desired-connection-method) | More connection methods are available for review in the MQTT5 Userguide
+
+### Service Client Samples
+##### AWS offers a number of IoT related services using MQTT. The samples below demonstrate how to use the service clients provided by the SDK to interact with those services.
+| Service Client Sample | Description |
+|--------|-------------|
+| [Shadow](./service_clients//shadow.md) | Manage and sync device state using the IoT Device Shadow service. |
+| [Jobs](./service_clients//jobs.md) | Receive and execute remote operations sent from the Jobs service. |
+| [Basic Fleet Provisioning](./service_clients//fleet_provisioning_basic.md) | Provision a device using the Fleet Provisioning template. |
+| [CSR Fleet Provisioning](./service_clients//fleet_provisioning_csr.md) | Demonstrates CSR-based device certificate provisioning. |
+
+
+### Greengrass Samples
+##### Samples that interact with [AWS Greengrass](https://aws.amazon.com/greengrass/).
+| Greengrass Sample | Description |
+|--------|-------------|
+| [Greengrass Discovery](./greengrass//basic_discovery.md) | Discover and connect to a local Greengrass core. |
+| [Greengrass IPC](./greengrass//ipc_greengrass.md) | Demonstrates Inter-Process Communication (IPC) with Greengrass components. |
+
+### Instructions
+
+First, install `aws-iot-device-sdk-python-v2`. Installation instructions for the SDK are [Provided Here](../README.md#Installation).
+
+Each sample's README contains prerequisites, arguments, and detailed instructions. For example, the [MQTT5 X509 Sample README](./mqtt/mqtt5_x509.md) is `mqtt5_x509.md` and the sample can be run with the following command:
+
+``` sh
+# For Windows: replace 'python3' with 'python' and '/' with '\'
+python3 mqtt5_x509.py --endpoint <endpoint> --cert <path to certificate> --key <path to private key>
+```
+
+### Sample Help
+
+All samples will show their options and arguments by passing in `--help`. For example:
+``` sh
+# For Windows: replace 'python3' with 'python' and '/' with '\'
+python3 mqtt5_x509.py --help
+```
+
+will result in the following print output:
+```
+MQTT5 X509 Sample (mTLS)
+
+options:
+  -h, --help    show this help message and exit
+
+required arguments:
+  --endpoint    IoT endpoint hostname (default: None)
+  --cert        Path to the certificate file to use during mTLS connection establishment (default: None)
+  --key         Path to the private key file to use during mTLS connection establishment (default: None)
+
+optional arguments:
+  --client_id   Client ID (default: mqtt5-sample-5873a450)
+  --topic       Topic (default: test/topic)
+  --message     Message payload (default: Hello from mqtt5 sample)
+  --count       Messages to publish (0 = infinite) (default: 5)
+```
+
+The sample will not run without the required arguments and will notify you of missing arguments.
+
+### Enable Logging
+
+Instructions to enable logging are available in the [FAQ](../documents/FAQ.md) under [How do I enable logging](../documents/FAQ.md#how-do-i-enable-logging).