Thanks Zeeman for your explanation.
Please, can you write us approx. how much you earn when farming?
Every group is responsible for all chunks in the address-range of that group. Say group AC is responsible for all data from AAA to CCC (on the network it's actually 512 bit, so extremely big address-range).
I suspect that the percentage of the data of your group that you store in your Vault will be part of the calculation. It's 100% when you keep all the group's chunks alive and ready for delivering.
Another thing is "Node Ageing". The network doesn't really trust you when you just joined as a Vault. So you start with "age 1" and when some full node disconnects from the group you are moved to the next group
as well. Now you age is 2. That group will forward you to a new group when 2 full nodes disconnect. So slowly you are hopping from group to group as your age grows. In all groups you need to do work, so deliver chunks out of cache, route data. And with low age you won't earn Safecoin for it. It's probably somewhere with age 3 or 4 that you start to earn some coins. And the idea is that you make more when your Vault becomes "older". So it pays to keep you node online for several days instead of several hours.
Then there's another issue
: What if your Vault has a high age and stores all the chunks. You could be payed 1 Safecoin per TB of data. But now the price of Safecoin goes to the moon, this means thousands and thousands of new nodes will come online and Farming would go out of hand. There's a solution for that as well. It's called the Farming Reward (FR). The network will always try to keep around 30% of free space. So if thousands and thousands of Vaults come online, and we have 60% of free data instead of 30% the FR will go down like a maniac. I guess they'll make the Farming algo's very quick to respond. So if there's 5% to much storage on the network, the FR will drop with 5% immediately.
So what's Farming gonna pay you??? It's probably a calculation with Node Age, FR, percentage of the groupsdata you store etc.
I guess the calculation can be easily made when the network is live. Your Vault will tell you what the average free space is. And with that info and the price of Safecoin you can calculate what a Vault with some higher age can make on a day. The brilliant thing is that the network doesn't care about the price of Safecoin in a direct way. If Safecoin rises 23% in 24H a lot of new people will start a Vault. The network picks up there's too much storage and the FR will go down immediately. Same the other way around; when there's not enough storage in the network the FR will go up aggressively. Just to make sure there will always be Farmers around.
We will all test this with test_farming and test_Safecoin. It will make all these details clear. Here's a reply by David Irvine
https://forum.safedev.org/t/rfc-45-node-ageing/157/7