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We've seen so far how to send data from an end-device to the Network Server.
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First, the end-device sends a packet to a gateway.
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Then, the gateway transfers it on the Internet to a Network Server and an Application Server.
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That's it.
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The LoRaWAN protocol stops here.
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From this point, we have the user data decrypted. In the LoRaWAN protocol,
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this user data is called the frame payload.
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If your Network Server provides a more secure environment with end-to-end security, you might have
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a different architecture, but it doesn't change the overall explanation.
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Indeed, you Application Server use to decrypt your data with the Application Session Key would be on
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the same location as your IoT platform.
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But really, what we're going to explain would be exactly the same.
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The question is now, what are we going to do with this data?
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Because we've set up a successful LoRaWAN transmission, and for that, we can be very glad indeed.
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But now, we need to give some value to this data:
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We want to save everything in the database.
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We want to perform calculation, prediction and possibly to apply Artificial Intelligence.
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We want to present things in tables, graphs or anything that suits our clients.
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And finally, we want to make these data available through a web service. So the user will be able to
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access and visualize these data from anywhere.
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Great.
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So, the good news is that this chapter is completely independent from the LoRa modulation and the LoRaWAN
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standards we have studied so far.
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That means that the following explanation can be easily transposed to any other protocols related to
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the Internet of Things.
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Okay, so before starting, let's remind some basic vocabulary:
- A frame that comes from the end device, and
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that  goes to the network server.
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then to the Iot platform is called a uplink frame.
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And, 
-A  the frame that comes from the IoT platform and that goes to the LoRaWAN server,
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then towards the end-device is called a downlink frame.
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Great.
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We already saw everything concerning the LoRaWAN protocol in the previous chapter.
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So, now we want to deal with the dialogue between the LoRaWAN server and the IoT platform.
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And in this chapter, we're going to see in details two protocols which are HTTP and MQTT.
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For now, we are just focusing only on the data transmission on the IoT platform.
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But later in this course, we'll build a complete IoT platform ourselves.
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So we'll be able to save data and visualize them in a nice way.
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Let's start with the HTTP protocol.