Difference between Notification and Indication

[beemavishnu]

Hello,

 

I have a query on Ack for Notification and Indication.

 

1) I pasted statement from below link,

https://devzone.nordicsemi.com/nordic/tutorials/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial

 

“The subtle, but important difference here is that by using indication your kit (the server) will require an application level acknowledgment in return after every transmission of updated data. By using notification, on the other hand, our kit will just "mindlessly" transmit data and not care about whether it is acknowledged by the application in the other end or not.”

 

Though Notification does not have “Attribute Protocol Layer” Acknowledgement, does not mean there won’t be any Acknowledgement from other device. I mean, even for Notifications there will be Link Layer/Physical layer acknowledgements from other device. Notification will NOT be sent “mindlessly”. If there is not physical Ack from other device, Notification will be retried.

 

2) Even Notification will be transmitted in synchronous to “Anchor point”, but not sent wherever within connection interval.

 

3) In case of Indication, “Attribute Protocol Layer” Acknowledgement will help in generating delay or synchronization at application level (Ex: DFU over the air).

 

Please correct my understanding I am wrong.

 

Thanks & Regards

Vishnu Beema

[Andy]

Check out this thread.

[beemavishnu]

Thank you for the post