From what I understand, after re watching the 2020 TTN conference video on YouTube Link about packet broker is that you need to have an assigned NetID which is only available as a member of the LoraWAN alliance. This costs ~US$3,000 per annum.
This is out of reach of most people who want to have the ability to operate a private gateway (or cluster of) to achieve a private LoRaWAn capability but provide the community at large the benefit of the gateway participating with TTN and passing (up and down link) traffic to users within the coverage of their gateway (or cluster of).
Please correct me if I am wrong.
Perhaps packetbroker needs to consider some sort of networking RFC1918 (192.168.x.x 172.16.x.x 10.x.x.x) equivalent for the NetID [edit… am aware of " NetID 00"] where localised use for the private is possible as a mask and the catch-all traffic is sent on.
Anyone doing this seriously is likely to be operating in a commercial context, so the additional costs shouldn’t be much in the grand scheme of things. You can rent a small block of IDs from TTI that will cost less than membership.
The alternative is to run the private network using a TTI instance that can then automagically peer.
It’s not clear what your project is about or indeed how many gateways make a cluster - why do you need a private network?
While packet broker should have been designed to solve this problem, specific questions here in the past reveal that at present it actually doesn’t do anything to address it at all.
Just like feeding multiple network servers directly, it makes it look like peering works, but actually the networks denial of service attack each other because theres no logic to let the loser of a conflict try a different gateway.
I would agree that the cost of running package broker is prohibitive for most. Add the complexity of the PB setup to the cost, makes it look even less attractive.
If someone with a private gateway/NS wants to contribute to TTN, then from my (greenhorn ) point of view it would be much easier, and cheaper (and maybe naive), to just setup 2 gateways at the same location, one for the private NS, the other for TTN. Just make sure of proper antenna distance between the two gateway. Sure, there is still chance of collisions for downlink transmissions, alas at a lower rate since there is a good chance that occasional simultaneous downlinks would be transmitted at different frequencies.
We may or may not like the idea of gateways being physically placed close together , but I think that over time, as LoRaWAN grows, gateways for various NS will be deployed within close distances, since operators try to place them at optimal locations. Thus the clustering of gateways at prime locations is almost inevitable and probably has already happened. Which rises the question what the practical impact on downlinks at such existing hotspots is. This impact could/should be measured with test nodes able to report missing testdata downlinks. I would expect that any serious network operator has such tests already in place to continuously measure quality of downlink service. (same goes for uplinks)
I think I will wait for a better or more elaborate explanation on how PB may be used in this “single HQ” location scenario with operators that wish to circumvent the stacked antenna situations you see in mobile network operator towers: either one takes it all, or it is a christmas tree with multiple same band antennas. Looking forward to updates on this on packetbroker.org
From any perspective a SW or network defined solution would be preferable IMHO. For economy, equipment maintenance… even when we dont dare to touch the holy grail of ownership…
With the current backend software multiple gateways is the only viable solution. It also increases the downlink capacity, the two networks won’t be competing for allowed airtime which might become a serious issue when firmware updates over the air are performed.
Mounting multiple antennas might not always be possible but is preferable for the foreseeable future.
And the cost of a lorawan gateway install is small compared to other solutions (like getting a netid from the Lora Alliance, at at least $3000 a year).
Since a few days I have installed a second gateway for TTN V3 in addition to my gateway for TTN V2. They are at the same location, there antennas have an altitude-difference of 2m.
They do not seem to influence each other, although they will. imho If one gateway transmits it will block the receiver of the other gateway. But they transmit rather seldom so that the chance of a signal coming through is high.
Using the same antenna might be a problem - not for receiving you ca use a splitter for this. But for transmitting - the transmitter of one gateway might blow up the receiver of the other gateway.
On the other hand combiner/splitter can have an isolation of more than 20dB - if the impedance-matching is good. The receiver of a gateway might withstand a power of -6dBm. What about using one antenna, a combiner and two gateways?
No risk - no fun!
As promised: the statement from Mikrotik support about the multiple server setting in the LTAP LR8:
Response:
Adding multiple servers may cause issues if an LoRa node is added to multiple applications, for example, one served on TTN and the other on Chirpstack, but, actually, I cannot think of a reason one should do that. On the other hand, if you have nodes that are added only to an application served on TTN and other nodes that are added to an application served on your own Chirpstack server, you can use a single gateway to get everything working.
Thank you to everyone who has invested a lot of time in exploring the details of Packet Broker. Since there are a bunch of open questions, I would like to invite you to the conference on Friday. We will have a breakout session on the packet broker at 11 am CET.
Please use the chat function to post questions which will be picked up by the team or Johan directly.
Hi all, great read here. Like Felix says, we’re doing a session on Packet Broker this Friday and the community can attend for free. I’ll be covering your things (no pun intended) mentioned here and in other places in the forum as well. I’ll be doing live Q&A in the chat.
In any case, I wanted to jump in here on a few issues raised here:
I agree with you that conflict resolution is trying alternative routes in real time. The Things Stack and Packet Broker are in fact designed for this on multiple layers.
There is one constraint though: once a downlink message has been scheduled on a gateway, it cannot be unscheduled. There are two reasons for this: 1) we don’t want to roundtrip to the gateway for (un)scheduling downlink because of latency (the gateway backhaul is most often the bottleneck to make RX1) and 2) packet forwarders don’t support unscheduling downlink.
What we do have, however, by design in The Things Stack and Packet Broker is:
Forwarders connected to Packet Broker report downlink scheduling result back to Packet Broker. This can simply be success, in which case it is assumed that the downlink message gets transmitted, or it can be one of the many errors (api/v3/enums.proto at e80ed37341424a094c84fd69200b908a8b5ad9d2 · packetbroker/api · GitHub), including COLLISION_PACKET. This is (will be) treated by The Things Stack Network Server as a scheduling failure and it will try again on a different downlink path, which could be another downlink path via Packet Broker.
Very interesting topic here, thanks for all the answers.
I agree with @alpu, it should be easy for any member to share their private gateways with the TTN community and to be able to have their private stack at the same time. I think having two gateways at the same spot is somehow a wast of hardware/money/power.
As a HAM radio community in Switzerland, we have access to some good located spots on mountains and we are slowly deploying LoRaWAN in our area. We are using our own stack on a local server for our traffic but want to help the TTN community as well. We cannot put multiples gateways on those places as they are all solar powered and we want to limit the power consumption. We are using Mikrotik wAP LR8 kits everywhere (easy to power from 24V) and without knowing this is problematic before reading this post, we are setting the two servers (our and TTNv3) on the gateways.
I understand the point that this is a problem as the two stacks are not aware of each other using the gateways at the same time. But buying a NetID for 3’000$ a year to peer with TTN is clearly out of question for a small community like us. We are not doing that for money, only on a voluntary basis to help the local community. We still want to help the TTN community and the only way we find today is to add the two servers on the gateways.
We do not have many local traffic, but let assume the two servers want to transmit at the same time on the same gateway. One of the two server will not be able to send the downlink and the device will not receive it. But anyway we are loosing traffic on air due to various reasons (weather, interferences…). The stacks and devices are anyway designed to account for packet losses: ADR algorithms will wait for an ack from the device, we have confirmed down/up link if we want to be sure that the information is received and so on. The protocol for the gateways is UDP, this do not guarantee that the information will be received by the gateways as well. I think the stacks and devices are already designed to account for small losses like that and without a better solution we will keep providing coverage for TTN this way. After all, we are all on a best effort basis, this is anyway better than no TTN gateway on this area.
I would be glad to change the way we do help the TTN community if technical solutions exist. Preferably without buying two gateways for each spot and without the 3’000$/year NetID.
There was a presentation on packet broker by @johan earlier today at The Things Stack Conference that showed how this can be solved. It will become available on YouTube in the (near) future. I’ll post the YouTube link when it’s available.