Sean Bowe@ebfull
UPDATE: The various orgs and protocol developers mentioned have agreed on the specific consensus rule changes for Ironwood, after settling the finer details.
Here's a summary:
1. Ironwood introduces a new pool using the Orchard protocol, just like the existing pool.
2. The circuit for the Orchard protocol—which applies to both the existing Orchard pool and the new Ironwood pool—will have a flag that consensus rules can toggle. This flag disables payments to *other* users within that pool, while maintaining the ability to create change notes. (This enables a privacy safeguard.)
3. The old Orchard pool will have this flag enabled after the network upgrade, and payments to the old pool will also be disabled by constraining valueBalance.
4. Because payments are disabled on the old pool, wallets must send new payments to Orchard receivers (inside existing unified addresses) via the new pool, and they should also migrate funds away from the old pool.
This combination enforces a bound on the circulating supply of ZEC through the use of the existing turnstile mechanism; the amount of ZEC that anyone can transact with is no more than the amount that is supposed to exist. Meanwhile, users' wallets can migrate funds to protect them from risk, which also gradually provides evidence that counterfeiting never took place.
Now that we have this decided, we'll collectively move on to the implementations, specifications, and ecosystem support/outreach. (We also have many different auditing and formal verification efforts taking place behind the scenes to provide assurance about the circuit correctness. More on that soon!)
