Certificate-based authentication in IOT Protocols - Step-by-Step Execution

Process Flow - Certificate-based authentication

Device wants to connect

↓

Device sends certificate

↓

Server verifies certificate

↓

Connection

The device sends its certificate to the server, which checks if it is valid. If yes, connection is allowed; if no, connection is rejected.

Execution Sample

IOT Protocols

Device -> Server: Send certificate
Server: Verify certificate
If valid -> Allow connection
Else -> Reject connection

This shows the basic steps of certificate-based authentication between a device and a server.

Process Table

Step	Action	Input	Verification Result	Outcome
1	Device sends certificate	Device certificate	Pending	Waiting for verification
2	Server verifies certificate	Device certificate	Valid	Certificate accepted
3	Server grants connection	N/A	N/A	Connection established
4	Device sends certificate	Device certificate	Pending	Waiting for verification
5	Server verifies certificate	Device certificate	Invalid	Certificate rejected
6	Server denies connection	N/A	N/A	Connection rejected

💡 Process stops after connection is either established or rejected based on certificate validity.

Status Tracker

Variable	Start	After Step 2	After Step 5	Final
certificate_status	Not sent	Valid	Invalid	Valid or Invalid
connection_state	Disconnected	Connected	Disconnected	Connected or Disconnected

Key Moments - 2 Insights

Why does the server reject the connection even though the device sent a certificate?

Because the certificate verification failed (see execution_table step 5), meaning the certificate is invalid or untrusted.

What happens if the certificate is valid?

The server accepts the certificate and establishes the connection (see execution_table step 3).

Visual Quiz - 3 Questions

Look at the execution table, what is the outcome at step 3?

A Connection established

B Connection rejected

C Waiting for verification

D Certificate rejected

💡 Hint

Check the 'Outcome' column for step 3 in the execution_table.

At which step does the server determine the certificate is invalid?

A Step 2

B Step 1

C Step 5

D Step 6

💡 Hint

Look at the 'Verification Result' column in the execution_table.

If the certificate_status variable is 'Invalid' after verification, what is the connection_state?

A Connected

B Disconnected

C Pending

D Unknown

💡 Hint

Refer to variable_tracker for 'certificate_status' and 'connection_state' values.

Concept Snapshot

Certificate-based authentication:
- Device sends its certificate to server
- Server verifies certificate validity
- If valid, connection is established
- If invalid, connection is rejected
- Ensures secure device-server communication

Full Transcript

Certificate-based authentication is a process where a device proves its identity to a server by sending a digital certificate. The server checks if this certificate is valid and trusted. If the certificate passes verification, the server allows the device to connect. If not, the server rejects the connection. This method helps keep communication secure by ensuring only trusted devices connect.