About this Release
Absolute Core 0.14.0.1 is a major release of the Absolute Core 0.14.0.x series.
This is a new minor version release, bringing various bugfixes and improvements. We consider this a stable release.
Notable changes
Support for IPv6 Masternodes
This release allows access to create IPv6 masternodes via the normal registration process
Fix for a DoS vector
This release fixes a serious DoS vector which allows to cause memory exhaustion until the point of out-of-memory related crashes. We highly recommend upgrading all nodes. Thanks to Bitcoin ABC developers for finding and reporting this issue to us.
DIP0004 - Coinbase Payload v2
Coinbase Payload v2 introduces new field merkleRootQuorums which represents the merkle root of all the hashes of the final quorum commitments of all active LLMQ sets. This allows SPV clients to verify active LLMQ sets and use this information to further verify ChainLocks and LLMQ-based InstantSend messages. Coinbase Payload v2 relies on DIP0008 (bit 4) activation.
DIP0008 - ChainLocks
This version introduces ChainLocks, a technology for near-instant confirmation of blocks and finding near-instant consensus on the longest valid/accepted chain. ChainLocks leverages LLMQ Signing Requests/Sessions to accomplish this. ChainLocks relies on DIP0008 (bit 4) activation and SPORK_19_CHAINLOCKS_ENABLED spork.
DIP0010 - LLMQ-based InstantSend
InstantSend is a feature to allow instant confirmations of payments. It works by locking transaction inputs through masternode quorums. It has been present in Absolute for a few years and been proven to work. Nevertheless, there are some limits which could theoretically be removed in the old system but doing so would have created risks in terms of scalability and security.
We introduce LLMQ-based InstantSend which is designed to be much more scalable without sacrificing security and which allows all transactions to be treated as InstantSend transactions. The old system differentiated transactions as InstantSend transactions by using the P2P message “ix” instead of “tx”. Since this distinction is not required in the new system, the P2P message “ix” will be removed after DIP0008 deployment (for now, transactions sent via "ix" message will be relayed further via "tx" message).
Network
Legacy messages mnw, mnwb, mnget, mnb, mnp, dseg, mnv, qdcommit and their corresponding inventory types (7, 10, 14, 15, 19, 22) are no longer suported.
Message version is extended with a 256 bit field - a challenge sent to a masternode. Masternode which received such a challenge must reply with new p2p message mnauth directly after verack. This mnauth message must include a signed challenge that was previously sent via version.
Mining
Due to changes in coinbase payload this version requires for miners to signal their readiness via BIP9-like mechanism - by setting bit 4 of the block version to 1. Note that if your mining software simply uses coinbase_payload field from getblocktemplate RPC and doesn't construct coinbase payload manually then there should be no changes to your mining software required. We however encourage pools and solo-miners to check their software compatibility on testnet to ensure flawless migration.
PrivateSend
The wallet will try to create and consume denoms a bit more accurately now. It will also only create a limited number of inputs for each denominated amount to prevent bloating itself with mostly the smallest denoms. You can control this number of inputs via new -privatesenddenoms cmd-line option (default is 300).
InstantSend
Legacy InstantSend is going to be superseded by the newly implemented LLMQ-based one once DIP0008 (bit 4) is active and SPORK_20_INSTANTSEND_LLMQ_BASED spork is ON.
Sporks
There are two new sporks introduced in this version - SPORK_19_CHAINLOCKS_ENABLED and SPORK_20_INSTANTSEND_LLMQ_BASED. SPORK_17_QUORUM_DKG_ENABLED was introduced in v0.13 but was kept OFF. It will be turned on once 55% of masternodes are upgraded to v0.14 which will enable DKG and DKG-based PoSe.
QR codes
Wallet can now show QR codes for addresses in the address book, receiving addresses and addresses identified in transactions list (right click -> "Show QR-code").
RPC, ZMQ and command-line changes
This release introduced various changes to these subsystems, please see detailed release notes for more info.
Release Notes
You can find detailed release notes at https://absify.me/support. The release notes also contain instructions and links to further documentation for masternode operators and miners.
Credits
Thanks go out to all Absolute Core contributors, everyone who submitted issues, reviewed pull requests or helped to translate on Transifex and also to the Dash & Bitcoin Core Developers.