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A side chain is a blockchain that works in parallel and independently to a base chain (like Bitcoin) and that allows the transfer of coins between both chains, without compromising the security of the base chain.
Among the applications of a sidechain, the creation of smart contracts of greater complexity than the natives of Bitcoin, increase the scalability and speed of transactions and interconnectivity with exchange houses, among others, stands out.
Research on sidechains gained further momentum in late 2013 and early 2014, as the debate over Bitcoin's scalability issues began to intensify and alternatives were sought in response to the proposal to increase the size of blocks.
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But these sidechains took a new turn when the idea of a bidirectional peg or two-way-peg was incorporated, which made interoperability between chains possible, and in October 2014 these ideas were formalized and published in the sidechains white paper.
There are said to be 2-way-peg when both currencies can be freely, automatically exchanged between chains without paying more than transaction fees and without incurring price negotiation.
All in all, the design of this type of sidechains can still be perfected, that's why a new side chain proposal called SyncChain has been made.
SyncChain enables much faster inter-chain token entry and exit without sacrificing security against double-spending attacks and reducing inbound and outbound connection times.
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SyncChain is one of the latest proposals for sidechains, and it can be said that it represents the most current stage in this short history of sidechains.
Although SyncChain offers many benefits over a Simplified Payment Verification (SPV) side chain, it is too early to start seeing operational, encryption, testing, simulations and security audits should validate every design decision.
More information:
https://www.criptonoticias.com/tecnologia/syncchains-evolucion-sidechains-bitcoin/
https://blockgeeks.com/guides/syncchains-the-evolution-of-sidechains/
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