how do I connect to mqtt.googleapis.com - google-cloud-platform

I need to connect my mqtt-spy client to mqtt.googleapis.com with rsa_public.pem and root.ca
What configuration parameters should be used?.
I attempted many possible combinations of options none worked.

That endpoint is an MQTT bridge used by Cloud IoT. It is extensively documented and I encourage you to review the docs:
https://cloud.google.com/iot/docs/how-tos/mqtt-bridge
It's possible Google applies constraints to the bridge to focus its use to client devices interacting with Cloud IoT so it may not present with 100% fidelity as an MQTT broker but, you should be able to configure mqtt-spy to connect to it as long as you're able to present as a device with certs.

Related

AWS IOT Core - Custom Authentication and ALPN

I am building an integration between IOT Edge Quectel_BG96 and AWS IOT Core. The requirements are:
These IOT edges should authenticate using Custom Authenticator ( Username and password )
Quectel_BG96 has difficulties to implment ALPN. This means that I am not able to connect from the device, as there is no way for us to set this parameter in the TLS connection.
I built everything and all pieces are working as expected: Able to authenticate, able to pub/sub with no issues, BUT not from the modem Quectel_BG96.
My question to the community is: Is there away I can skip the ALPN requirement? Or to anything in AWS infra that plays as a middleware between two devices: Edge and AWS IOT Core?
Thank you in advance for any help
I tried connecting to AWS IOT Core using mosquito_pub and it works with no issues. I am expecting to be able to connect to AWS IOT Core from the iot edge and without setting up the ALPN.
According to the doc, you can use mqtt over port 8883 without setting the ALPN. But it is with x509 certificates. Otherwise it is mqtt over websockets.
Here is the link:
https://docs.aws.amazon.com/iot/latest/developerguide/protocols.html

Google Cloud IoT- How to publish to the same topic with multiple IoT devices and process it by cloud functions

In my project multiple IoT devices need to publish to a single topic and cloud functions listening to that topic need to process data published by IoT devices. Multiple devices should be able to publish at the same time.A MQTT broker logic is needed. But in Google IoT Core "The MQTT bridge allows only a single connection for a given device ID. If a second device connects with the ID of a device that is already connected, the older device connection will be closed automatically.".
I am new to google cloud IoT and trying to understand basic concepts. I have looked into gateways but I am not sure that gateways work as broker. Can multiple devices publish through a gateway to a same single topic? or should I implement/add a MQTT broker(mosquitto I guess) myself or is there an another way to use google Cloud IoT in my case? Could you guys direct me to the right direction. Opening sub/pub topics for each device doesn't sound right because in my project there can be thousands of IoT devices.
Let all the devices in the registry publish messages to the common topic given to the registry.Then trigger a cloud function with this topic.
You can process the messages with cloud function based on the deviceId

How to create a unique IOT Thing on AWS automatically through a Flutter app?

I am working on a project wherein a mobile app (Flutter app) should create a unique identity (IOT thing) of my IOT device machine (on AWS) as soon as the user logins onto the app and also it should establish a connection (and subsequent communications) with the isolated IOT device after its configuration (Somewhat similar to Google Home configuration process).
The process starts with user logging onto the app (using AWS Amplify/Congnito to automatically add the user account in the cloud). Subsequently, the app needs to configure the IOT device (ESP32) and send Wifi credentials of home network by connecting to ESP's WiFi AP. However, since both the app and IOT device are isolated from each other (except during the configuration process), I don't have much idea on how exactly will mobile app connect (creating a unique IOT thing automatically) and communicate with the isolated IOT device over AWS IOT cloud.
I have worked with some of the AWS services like AWS Lambda, DynamoDB, AWS IOT for quite a while, hence I am aware of the basics. One of the possible solutions for the above maybe Fleet Provisioning by a Trusted User feature provided by AWS IOT (I did read it's documentation, but still confused). We can also use ESP32's Bluetooth feature for the app to scan nearby devices with which it needs to connect with, but I am not sure how will the connection establish through AWS cloud.
Since I am a beginner to AWS cloud services, it'd be great if someone can provide a possible solution for the above in detail. Also if possible, please provide a solution which would work incase of a large-scale deployment of the above project.
The parts you may be missing are missing are 1) MQTT messaging, which is the IoT message broker service provided by IoT Core, and 2) the need for an application program interface to handle creating and activating devices.
MQTT is a lightweight and widely adopted messaging protocol that is designed for constrained devices.
Your devices (things) will need to communicate back to AWS via MQTT messages, which are captured and processed by the IoT Rules service.
These rules typically trigger Lambda functions, which implement the process logic you need for your application.
See https://mqtt.org/ and https://docs.aws.amazon.com/iot/latest/developerguide/what-is-aws-iot.html
2} you will want to implement a simple API to handle device activation. The AWS API Gateway service makes it easy to implement APIs. For example, you can implement an endpoint for POST /device/ to create a device. That endpoint can trigger a Lambda handles device provisionsing.

How does AWS IOT's device gateway provide bi-directional communication?

One of the core features of AWS IOT is to provide bi-directional communication through the device gateway. Knowing that the implementation is private, can anyone conceptually explain how the gateway is able to push messages to a device on my local network? Does the service maintain a persistent connection to the device?
To add context, in my experience prior to AWS IOT, if I wanted to communicate with my embedded app (using HTTP) I would need to set up port-forwarding, so it's a mystery to me why device gateway could work without this step.
AWS IOT is implemented with MQTT, an MQTT connection is permanent TCP connection from the device to the gateway (broker), meaning that when there is a need to send a message to the device this connection is used.
Because the connection is initiated from the device to the gateway there is no need to set up any port forwarding (apart from that which is automatically handled by a home router doing NAT)
AWS IoT, uses the Pub/Sub pattern to provide communication between devices and message broker.
Publish–subscribe is a messaging pattern where senders of messages,
called publishers, do not program the messages to be sent directly to
specific receivers, called subscribers, but instead categorize
published messages into classes without knowledge of which
subscribers, if any, there may be. Similarly, subscribers express
interest in one or more classes and only receive messages that are of
interest, without knowledge of which publishers, if any, there are.
More about this pattern here: https://msdn.microsoft.com/en-us/library/ff649664.aspx

Building a web application using WebSockets and AWS

I'm trying to create a collaborative web application where multiple users can work together on various (shared) projects. So far I have a JavaScript client and one local jWebSocket server.
To remain scalable upon deployment, I thought of two options:
Option 1
I can use AWS IoT instead of multiple jWebSocket servers. Publishing changes of a project is easy, I would just need to publish to e.g. /project/{project-id}. But how would the traditional request-response mechanism work?
The Problem: EC2 instances handling requests would be reachable by publishing to distinct topics (e.g. /server/1). But when the JS client connects to AWS IoT, it does not know of any EC2 instance to send requests to. How could I assign each client to an instance/topic?
Option 2
Run jWebSocket servers on multiple EC2 instances behind an AWS Application Load Balancer. The balancer would simply assign each client to a server and the traditional request-response flow would not be a problem. But what about pushing changes?
The Problem: Because each server has its own set of connected clients, it can not push changes to clients connected to another server.
Remarks
Mixing jWebSocket to send requests to and AWS IoT to receive events from seems like a sloppy solution.
I assume I can programmatically adapt the IoT policies per cognito identity to allow/deny the subscription to specific projects.
Using AWS Lambda and relinquishing servers altogether is not an option due to the high latency introduced by Lambda (if you've made different experiences, please share).
Related posts
IoT request response protocol
Thanks for any thought you could give me on this issue.
I've got it. The first suggestion in this question pointed me into the right direction. The solution allows all clients to maintain a direct WebSocket connection to the server they originally connected to, without subscribing to specific topics.
It works as follows:
When a client connects to a server, the server subscribes to the client's channel
If a server needs to send a message to a client that is not connected, it publishes that message to the client's channel
(you guessed it) The server that is subscribed to the channel can then process the message on the first server's behalf
"Pusher" in the diagram describes this SaaS, but can of course be replaced by any other messaging service.