Understanding the Send Message Node

In this quick tutorial, we will cover “Understanding the Send Message Node”. The Catenis platform is powerful and also allows you to send messages using the bitcoin Blockchain.  The “Send Message” node allows you to send messages from one Catenis virtual device to another. This can be a sending message from one application to another and have these messages recorded to the blockchain.

This node can also send a message requesting a Read confirmation, making it cryptographically provable that the receiving device has read the message.

In this video we will cover:

• General concepts of sending messages with Catenis
• What are Read receipts when sending messages
• Importing a working Send Message Node flow
• Running the flow to see its results

Prerequisite

• A Free Catenis Development account or Production account
• Node-RED installed on either a local or cloud environment
• Catenis Flow Pallet installed on Node-RED
• Two Catenis Virtual Devices configured on Node-RED
• Basic understanding of how to use Node-RED
• Basic understanding of Bitcoin Blockchain concepts
• Basic understanding of IPFS

Thank you for watching Understanding the Send Message Node in the Catenis Flow tutorial series. Watch the next video, Working with the Send Message Node, to further expand your knowledge.

Links from this video for easy access:

• Working with the Read Message Node: https://blockchainofthings.com/tutorials/work-with-read-message-node
• Send Message Node Documentation on our website: https://blockchainofthings.com/send-message-node/
• How to Configure a Virtual Device: https://blockchainofthings.com/tutorials/configure-virtual-device
• Working with the Send Message Node: https://blockchainofthings.com/tutorials/work-with-the-send-message-node

To sign up for your free account, head to our website www.blockchainofthings.com.

Join our community forum for the quickest response time to all your questions and concerns. This forum is our customer support. https://forum.blockchainofthings.com/

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Hi, this is Clara for Blockchain of Things.

In this tutorial, you will learn about the Send Message Node

and how it’s used in Catenis Flow.

The Send Message Node allows you to send messages from

one Catenis Virtual Device to another and have these messages recorded to the blockchain.

This node can also send a message requesting a read confirmation making it cryptographically provable that the receiving device has read the message.

Now, let’s take a look at the properties panel fields.

Add a descriptive name of your choice to the name field that will help differentiate this node from others of the same type on
the Node-RED workspace.

Set a previously configured

Catenis Virtual Device in the connection field or configure a new Virtual Device.

In the target device ID field, enter the device ID of the device you wish to send the message to.

Check the box in the product unique ID field,
if the ID you just supplied is a product unique ID.

Catenis Flow will automatically encode the content you send into one of three types you designate.

UTF-8,

Base64,

or Hexadecimal.

Deselect the encrypt checkbox if you want your
data to be logged in clear text.

You can choose to disable off-chain messages and send a standard message instead

by unchecking the off-chain message checkbox.

Catenis Flow supports two different modes of storage

and adds automatic detection based on content size.

This storage mode can be set in the storage field.

Auto mode will automatically detect the size of the content you are logging

and if the content is 75 bytes or less, it will place the content in a bitcoin transaction.

If the content is above 75 bytes, it will create a signature hash of the content and place the signature hash in the bitcoin transaction and place the content on IPFS.

The embed setting will force the content being logged to be embedded within a bitcoin transaction.

If you select the embed setting and the content is above
75 bytes, Catenis Flow will return an error message.

The external setting will force the content
being logged to be hashed.

Its hash will be placed within a bitcoin transaction and its content will be placed in external IPFS storage, even if the content is smaller than 75 bytes.

Indicate whether you wish to send the message with the read confirmation capability enabled in the read confirmation field.

This will record the target device’s read event to the blockchain

and send a notification of confirmation to the device sending the message that the message has been read.

The notification is sent in real-time and requires that a notification channel is active.

The async checkbox forces the content to be logged asynchronously

and is useful when handling content that is large.
Typically, above 10 megabytes.

Now, let’s take a look at the example flow found at this link:

Copy the example flow.

Click the Node-RED hamburger menu and click Import.

to display the import flow dialog box.

Paste the flow into the import box and click the import button.

This flow is a working example implementing
the Send Message Node.

Note, that after importing the example flow,

you will need to set the Catenis Flow Nodes to your
own previously configured virtual device.

If you don’t remember how to do this,
check out the video at this link:

Now, go back to the same link where you got the example flow and copy the example JSON object.

Which you can pass into this flow to see how it works.

Note, that you’ll need to modify the target
device ID in the JSON object.

Replace these hash signs with your own target device ID.

Now, pause this tutorial to explore this flow on your own.

In the next video, you’ll learn to create this flow from scratch.

Excellent!

After watching this tutorial, you should understand
Send Message Nodes.

The true power of blockchain, is only just now beginning

to be realized by developers like you, using the Catenis Second-Layer protocol to develop decentralized applications that will define the future of digital devices and systems.

In our next tutorial, you’ll learn how to use the Send Message Node in your own flow.

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