Overview

In this lesson, we will take a closer look at how we communicate with the modem core on the nRF91 Series SiP. We will start by introducing the nRF91 Series communication stack and move our way through the layers. On the modem side, you will learn about the transport layer protocols TCP/UDP and the accompanying TLS/DTLS and the advantages and disadvantages of each. Then we look at how the modem side and the application processor side communicate through the Modem library and socket interface in Zephyr.

In the exercise section of this lesson, we will use the socket API to create a UDP socket and establish a connection to an echo server to send and receive UDP packets.

Objectives

• Learn the fundamentals of network programming, including sockets and the transport protocols UDP and TCP, and understand the advantages and disadvantages of each.
• Examine the Modem Library and its role in communication between the application processor and the modem.
• Go over the basics of Zephyr’s socket implementation.
• Practice through hands-on exercise how to utilize the socket API to create a UDP socket and send UDP packet to a server.