Protocol related updates:
- The minimum relay fee has been lowered to 1000 litoshis per kB (0.00001 LTC). This is to prepare for dropping the minimum transaction fee to the same 1000 litoshis per kB in the next release.
- Lowering minimum fee on litecoin core to 0.0001LTC: Next release.
Litecoin Core version 0.15.1 released on 22 January 2018.
Network fork safety enhancements
A number of changes to the way Litecoin Core deals with peer connections and invalid blocks have been made, as a safety precaution against blockchain forks and misbehaving peers.
- Unrequested blocks with less work than the minimum-chain-work are now no longer processed even if they have more work than the tip (a potential issue during IBD where the tip may have low-work). This prevents peers wasting the resources of a node.
- Peers which provide a chain with less work than the minimum-chain-work during IBD will now be disconnected.
- For a given outbound peer, we now check whether their best known block has at least as much work as our tip. If it doesn’t, and if we still haven’t heard about a block with sufficient work after a 20 minute timeout, then we send a single getheaders message, and wait 2 more minutes. If after two minutes their best known block has insufficient work, we disconnect that peer. We protect 4 of our outbound peers from being disconnected by this logic to prevent excessive network topology changes as a result of this algorithm, while still ensuring that we have a reasonable number of nodes not known to be on bogus chains.
- Outbound (non-manual) peers that serve us block headers that are already known to be invalid (other than compact block announcements, because BIP 152 explicitly permits nodes to relay compact blocks before fully validating them) will now be disconnected.
- If the chain tip has not been advanced for over 30 minutes, we now assume the tip may be stale and will try to connect to an additional outbound peer. A periodic check ensures that if this extra peer connection is in use, we will disconnect the peer that least recently announced a new block.
- The set of all known invalid-themselves blocks (i.e. blocks which we attempted to connect but which were found to be invalid) are now tracked and used to check if new headers build on an invalid chain. This ensures that everything that descends from an invalid block is marked as such.
Miner block size limiting deprecated
Though blockmaxweight has been preferred for limiting the size of blocks returned by getblocktemplate since 0.13.0, blockmaxsize remained as an option for those who wished to limit their block size directly. Using this option resulted in a few UI issues as well as non-optimal fee selection and ever-so-slightly worse performance, and has thus now been deprecated. Further, the blockmaxsize option is now used only to calculate an implied blockmaxweight, instead of limiting block size directly. Any miners who wish to limit their blocks by size, instead of by weight, will have to do so manually by removing transactions from their block template directly.
Duplicate wallets disallowed
Previously, it was possible to open the same wallet twice by manually copying the wallet file, causing issues when both were opened simultaneously. It is no longer possible to open copies of the same wallet.