Light Hotspots Explained

What the heck is a Heli­um Light Hotspot, and why does it mat­ter? If you’re not tech savvy, the whole thing can seem con­fus­ing. Let’s clear it up.

We’ll begin with the dif­fer­ent types of Hotspots: Reg­u­lar, Light, and Data Only.

Reg­u­lar (I call ’em Full Fat) Hotspots are what Heli­um start­ed out with. They cre­ate chal­lenges, they bea­con, they wit­ness oth­er hotspots, AND they store a copy of the blockchain on ’em. That last part began cre­at­ing prob­lems as the net­work and the blockchain grew.

As the blockchain grew, it took up more and more of the mem­o­ry of those hotspots, caus­ing the blockchain to bog down. With the blockchain bogged down, hotspots had trou­ble get­ting their wit­ness and bea­con receipts record­ed, which caused spiky (and unset­tling) earn­ings as well as blockchain stalls. Nobody likes it when your mon­ey stalls. 

To solve this, the Heli­um com­mu­ni­ty came up with, vot­ed on, and passed the idea to cre­ate a new enti­ty on the net­work called a Val­ida­tor. Val­ida­tors don’t do any­thing except blockchain stuff. They nei­ther bea­con nor wit­ness. They can *cre­ate* a chal­lenge for Light Hotspots, but for now (March 2022) they just val­i­date (hence the name) all the receipts for all the chal­lenges and wit­ness­es and bea­cons that hotspots sub­mit. With those val­i­dat­ed receipts they form a block and add it to the blockchain.

Hav­ing Val­ida­tors allows us (all of the Heli­um net­work) to cre­ate and use what’s called a “Light Hotspot”. Light Hotspots don’t have to keep a copy of the blockchain; Val­ida­tors do that for them. 

Val­ida­tors can also cre­ate Chal­lenges for Light Hotspots to Bea­con. I know, I know, this is get­ting confusing.

To clear it up, here’s a short dia­gram of how the Proof of Cov­er­age Cycle works (the num­ber of hotspots has now dropped from 25 to 14)

Light Hotspots will only be able to do steps 2 and 3, above. Those earn the lion’s share of PoC HNT.

Light Hotspots won’t do step 1 or 4. You may think that’ll lose you a bunch, but it won’t. A Light Hotspot miss­es out on earn­ing HNT because it won’t cre­ate Chal­lenges (aka being a PoC Chal­lenger.) Cre­at­ing Chal­lenges does­n’t earn very much; less than 1% of all HNT dis­trib­uted per epoch. An epoch is 30 blocks, and blocks are mined about one every minute.

Light Hotspots will still be able to earn for Bea­con­ing (being a Chal­lengee) and Wit­ness­ing. Here’s how it breaks down:

Now, that leaves one more enti­ty to deal with, a Data Only Hotspot. Data Only Hotspots will ONLY be reward­ed for pro­cess­ing data. They won’t be able to earn for chal­lenges, wit­ness­es or bea­cons. They won’t need to. Data Only Hotspots are what the 5G ver­sion of a hotspot will be; Data Mon­sters, and almost noth­ing else. 🙂 

So, that’s the Proof Of Cov­er­age Cycle, which you need in order to under­stand the next part.

Now, let’s get into what makes a Light Hotspot dif­fer­ent from a Reg­u­lar (Full Fat) Hotspot in slight­ly more tech­ni­cal terms. 

The flow starts with Sen­sors, because that’s what Heli­um is built for.

This intro­duc­tion of “Sen­sors” can be con­fus­ing, because most of what you’ve paid atten­tion to and heard about so far is your hotspot (also known as a “gate­way”) get­ting reward­ed sole­ly for con­nect­ing (Chal­leng­ing, Bea­con­ing, & Wit­ness­ing) to oth­er hotspots. 

Still, sen­sors are the whole rea­son the net­work is being built, so I’m includ­ing them in their right­ful posi­tion at the top of the line.

For now, let’s see what it used to look like, before Val­ida­tors. This was the case for all cur­rent pro­duc­tion hotspots as of July 2021 (OG, RAK, Sense­cap, Syn­cro­bit, Nebra, etc.) 

Both the Min­er & the Pack­et For­warder are on the same device. This way the Min­er could keep a copy of the blockchain for itself as well as cre­ate, issue, and record Chal­lenges, Bea­cons, and Witnessing.

The Sen­sor picks up data from the envi­ron­ment and pass­es it to the Sen­sor Node. The Sen­sor Node trans­mits it to the Gate­way (Hotspot). The Hotspot spends most of its time lis­ten­ing for those data pack­ets com­ing from Sen­sor Nodes. Occa­sion­al­ly, a Hotspot will Bea­con out a mes­sage of its own for oth­er Hotspots to hear that essen­tial­ly says, “Here I am, check the strength and bear­ing of my sig­nal just to be sure.” 

Oth­er hotspots Wit­ness that Bea­con, record that trans­ac­tion, and then a group of Hotspots (the Con­sen­sus Group) agrees on which trans­ac­tions are valid and which are gam­ing, spoofs, or just mis­takes. They all con­nect via some kind of inter­net con­nec­tion; WiFi, Eth­er­net, Cell Back­haul, etc. 

Any data that actu­al­ly got passed from Sen­sors goes to the LoRa Router (in most cas­es Heli­um Con­sole, although you can run your own.)

Final­ly, that data is turned into a form more read­able by humans on an Inte­gra­tion Serv­er, like MyDe­vices Cayenne, Dat­a­cake, or others.

So, that’s how it worked BEFORE Light Hotspots. Can you see the prob­lem? If a tiny lit­tle com­put­er (basi­cal­ly a Rasp­ber­ry Pi) has to do all of that AND keep a copy of the blockchain on it, even­tu­al­ly it gets over­whelmed. What’s the solu­tion? Don’t make it do so much com­put­ing-heavy work.

Now let’s look at a Light Hotspot, which keeps the radio ele­ment but removes the com­put­ing & data-heavy require­ments of the min­er from the device, and puts that onto the Validators.

Light Hotspots still do the “radio” things; Issue bea­cons and wit­ness oth­er bea­cons. They just don’t have to do the resource inten­sive record­ing any­more; the Val­ida­tors are doing that. 

The flow after Val­ida­tors is the same as before: Through a LoRa Router, then an Inte­gra­tion Server.

It’s impor­tant to note that what’s get­ting “val­i­dat­ed” by val­ida­tors is the pas­sage of data; NOT the data itself. That data “lives” out­side the blockchain and is heav­i­ly encrypted. 

All of this is also laid out over on the Heli­um site, where you can see the mile­stones and dates for when all this gets completed. 

Can you see the dif­fer­ence between Light Hotspots and Full Fat Miners? 

Yep, a Light Hotspot is JUST a pack­et for­warder, which is basi­cal­ly just a radio con­nect­ed to the inter­net. It can trans­mit (bea­con) and receive (wit­ness) oth­er gate­ways, and it can do the same for sen­sor nodes. It leaves all the heavy lift­ing of min­ing and val­i­dat­ing to the Validators.

A Reg­u­lar “Full Fat” Hotspot (every cur­rent pro­duc­tion min­er as of July 2021) has both the Min­er AND the Pack­et For­warder on it. Here’s what the net­work data traf­fic looks like for a group of hotspots. Looks like it most­ly stays below 350 kpbs. You’ll notice a lit­tle yellow/orange line at the bot­tom. That’s the net­work data trans­fer for a pack­et for­warder (aka Light Hotspot.)

That group of Heli­um Hotspots have to send ALL of their min­ing work to oth­er min­ers. That’s any­where from 20–90 GB month! It’s also why the blockchain was bog­ging down before Val­ida­tors came online. At any one time, only 16 full fat min­ers (run­ning on lit­tle Rasp­ber­ry Pi’s!) were pro­cess­ing ALL of the trans­ac­tions sub­mit­ted to the entire blockchain from 90k oth­er Hotspots. Whew!

In com­par­i­son, a Light Hotspot uses around 100 MB/month. Light Hotspots will still be able to Wit­ness and Bea­con and earn from doing that, along with earn­ing data cred­its for the data they process. Here’s the same graph with just a Light Hotspot on it (the host took it off at 1600 for main­te­nance and fid­dling, so it stopped total­ly then.)

Since they’re trans­fer­ring so lit­tle data, this means that Light Hotspots can use tiny lit­tle com­put­ers (like a Pi Zero or small­er) that don’t get bogged down try­ing to process the trans­ac­tions of 90k+ full fat hotspots. 

That should help with under­stand­ing Light Hotspots and why they’re impor­tant. Hit me up with ques­tions in the com­ments, and if you’d like to go deep­er in the Heli­um net­work, con­sid­er hir­ing me to help with your next project.

Oh, and in case you want a quick vocab rehash:

Sen­sor — A device that col­lects envi­ron­men­tal data. This could be tem­per­a­ture, wind speed, the num­ber of cars parked in a park­ing lot, etc.

Sen­sor Node — This trans­mits the sen­sor data to the gate­way. Many times a Sen­sor (like the LHT65) con­sists of both a Sen­sor and a Sen­sor Node.

Gate­way — This is what you prob­a­bly think of as a Heli­um Hotspot. A Gate­way is the thing that receives data from a Sen­sor Node, then pass­es it on to the net­work. Gate­ways ALSO receive and trans­mit data with oth­er gate­ways, a process called Wit­ness­ing and Bea­con­ing. That’s cov­ered in depth, here.

Min­er — A min­er is what records the pas­sage of infor­ma­tion (NOT the infor­ma­tion itself) and adds it to the blockchain, so any­one can see the infor­ma­tion flow. Again, they CAN’T see the data (it’s encrypt­ed), but they can see that data was passed.

Pack­et For­warder — This is the radio part of a cur­rent pro­duc­tion hotspot. It trans­mits (bea­cons) out, most­ly to prove it is where it says it is. It also lis­tens for incom­ing pack­ets of infor­ma­tion from Sen­sor Nodes.

Val­ida­tor — The Val­ida­tors do what the Min­ers used to do, and they’ll even­tu­al­ly take over all min­ing oper­a­tions. Val­ida­tors con­firm, or val­i­date, the trans­ac­tions sub­mit­ted by the min­ers (and in the future, pack­et for­warders) to the blockchain. Val­ida­tors are what make the infor­ma­tion on the blockchain trustworthy.

Net­work Con­nec­tion - You need to con­nect your Hotspot or soon, Light Gate­way, to the inter­net some­how. This can hap­pen via WiFi, and Eth­er­net cord, by cell con­nec­tion (also known as “cell back­haul”) or satel­lite connection.

LoRa Router — Heli­um Con­sole is an exam­ple of a this. A LoRa router is the thing that takes the infor­ma­tion sub­mit­ted from the min­er through the blockchain and begins to get it into read­able form.

Inte­gra­tion Serv­er — This is what allows you to actu­al­ly “see” the data and use it, as a nor­mal human and not a machine or high wiz­ard of tech. You can use MyDe­vices Cayenne, or Dat­a­cake, or any one of a num­ber of ser­vices like those. 

This post was writ­ten with tech­ni­cal help from @jerm on Dis­cord. All mis­takes are mine, all right­eous accu­ra­cy is his.