We're still trying to figure out why the OTAA activation mode is better than ABP. When an end-device is 1
activated on a specific network, 2
it has a network session key, an application session key and a device address. 3
Now, let's say that for some reasons you want to charge your network operator. 4
For example, you had a subscription on the Helium network, but now you want to charge for Actility 5
or for TTN (The Things Network). 6
So what are your options? 7
If your end device is in ABP, 8
then you just have to copy the device address, the network session key and the application session 9
key into the new network server. 10
That's easy and it works well. 11
If your end device is in OTAA, then you just have to copy the active LoRaWAN session into the new network 12
server. 13
The session is once again the current device address, the network session key and the application session 14
key. 15
Again, that's easy and it works very well. 16
Anyway, it's the only option if your device is not able to rejoin the network server. 17
But there is something wrong with these two solutions. 18
The device adress copied from the old network 19
server doesn't belong to the range of the new network server. 20
Okay, that's something new that we haven't explained yet. 21
So let's take a few seconds to talk about this. 22
If you are a network operator, you can ask the LoRa Alliance to have a specific range of device address. 23
You should be the only one to use it. 24
However, if some other end device uses this range, this is not a security threat. When an end device belongs 25
to a specific range, 26
we said that it belongs to a specific network. 27
For example, when you use TTN, the device adress provided always starts with the same prefix or 28
0x26 or 0x27. 29
At the University we bought 1024 addresses starting from 0xFC014800 to 0XFC014BFF. 30
So we should be the only one to use it when we set up our own network server. 31
Okay. 32
But when is it important? 33
It's important when we set up a roaming agreement with another network. 34
That could be the case. 35
For example, if you need a coverage extension or a gateway densification, we are not going to dive into the roaming 36
features because it's an advanced topic. 37
But if you're interested, you will find everything you need to know in our free e-book on our website. 38
Anyway, if we come back to our two previous solutions, then we kept the old device address, which 39
belongs to the old network. 40
It means that you can't have a new roaming agreement with anyone because your partner would think that 41
you still belong to the old network operator. 42
However, if you don't do any roaming, it works. 43
It's not a really nice solution, but it works. 44
Do we have a better option ? 45
Yes, but only if we use OTAA. In that case, instead of copying the session information, we only copy 46
the entire device profile devEUI, appEUI, joinEUI and app Key. 47
However, that works only if you are able to ask you end device to rejoin. 48
And in that case a new session is going to be shared between the network server and the end device with 49
a new device address, a new network session key and a new application session key. 50
And obviously the new device address will belong to the new network server range. 51
So we pointed out another advantage of using OTAA instead of ABP. 52
However, even in OTAA, changing network operator is not an easy task if you really want to have a 53
seamless process for changing operator in LoRaWAN you should consider to use a join server. 54
But again, it's an advanced topic that you can find in our book.