From 14a311f25cbcb53365a90ddf21f4a6f9e3975e51 Mon Sep 17 00:00:00 2001 From: Mark Spanbroek Date: Wed, 1 Jun 2022 13:04:51 +0200 Subject: [PATCH] Repair incentive not longer grows over time Use the collateral instead of missed payouts as incentive for repairs. --- design/marketplace.md | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/design/marketplace.md b/design/marketplace.md index 79d4b62..e6d2c34 100644 --- a/design/marketplace.md +++ b/design/marketplace.md @@ -98,21 +98,11 @@ The time interval that a slot is filled by a host determines the host payout; for every second of the interval a certain amount of tokens are awarded to the host. Hosts that fill a slot are required to submit frequent proofs of storage. -When a proof is missed, the collateral associated with a slot is mostly burned, -except for a fee for the one who marked the proof as missing. The slot is now -considered empty again until another host submits a correct proof together with -collateral. - -To incentivize repair, we allow the host that takes over a slot to count the -interval between the missed proof and the new proof towards its own profits. -This means that when a proof is missed, the incentive to repair increases over -time. - -The situation where the payout on repair becomes larger than the required -collateral is an interesting one. On the one hand, this could be an opportunity -for zero-cash entry into the network. On the other hand, it might lead to -undesired behavior because the loss of collateral is no longer that important -for a node. This is probably worth looking further into. +When a proof is missed, the collateral associated with a slot is used to pay a +fee to the one who marked the proof as missing. The rest of the slot collateral +is reserved for repairs. The slot is now considered empty again until another +host submits a correct proof together with collateral. Payouts for the time +interval that a slot is empty are burned. Contract lifecycle ------------------ @@ -165,6 +155,22 @@ The client is able to retrieve any funds that are left in the contract. --------- +Repairs +------- + +When a slot becomes empty, the remaining collateral associated with the slot is +used as an incentive to repair the lost content. Repair typically involves +downloading other parts of the content and using erasure coding to restore the +missing parts. This incurs costs for a host. To compensate the host for these +costs it receives not only its own collateral back at the end of the contract, +but also the remaining collateral from the host that failed to hold a slot. + +We expect the collateral to be significantly higher than the costs of repair. +This means that hosts in the network can benefit greatly from repairs, and they +may prioritize repairs over filling slots in new contracts. This is intentional, +we want the network to prioritize honoring existing contracts over starting new +ones. + Renewal -------