This week I started finished the design for the network connection between the raspberry pi and the AWS server. We are still planning on using a UDP connection here to transmit packets, the packets will be a struct of the micID, audio bytes and direction of arrival information for the audio. The micID is assign to a single rapsberry pi audio device from the server, when the connection is first made. The AWS Server will receive information that the audio device wants to connect and will return the mic ID, this will be resent until the raspberry pi audio device receives the micID or the connection times out. On the server both listen and send will need to run on separate threads to make sure that the server is always listening. There will also be a separate thread for each audio device connection to the server.
I set up a simple server code to test the connection between the aws server and the raspberry pi. Since the AWS server is remote it is in a different wifi network so I had to set up port forwarding, so that the raspberry pi can access the server code on the AWS Server. AWS has its own way for users to setup port forwarding, using AWS Systems manager, I have been following this tutorial https://aws.amazon.com/blogs/mt/amazon-ec2-instance-port-forwarding-with-aws-systems-manager/.
We also received the AWS credits so we upgraded our ec2 instance to m5a.large, we are tracking our usage of the server.
I am currently on schedule, In the next week I am going to complete the code to handle the networking from raspberry pi to AWS Server, this code will include the initial raspberry pi audio device handshake with the AWS server, and the transmission of our packets.