Crypto community should decide the question: is it time to activate SegWit, that is, will the bitcoin protocol be changed? We tell what it means for miners, developers, investors and users of crypto-currencies.

A vigorous discussion of options for scaling the bitcoin core has reached a decisive phase. Both the most popular scaling project today - BIP148 and SegWit2x - imply the activation of Segregated Witness (SegWit) within a month, followed by a one-month update of the protocol.

At the same time, there is a serious risk that bitcoin will "split". BIP148 and SegWit2x can branch off from the existing bitcoin protocol, which in turn will lead to new splits.

What does Segregated Witness activation mean?

SegWit is an updated backward compatibility protocol originally proposed by the Bitcoin Core development team. Since December 2015, when this idea first appeared, it has become the cornerstone of their scaling project and is now used by many active sites of bitcoin.

SegWit is also now part of the New York agreement, signed in May: an alternative scaling project supported by 56 companies and miners. And user activated softphone (UASF) BIP148, the same offer to improve Bitcoin 148, scheduled for August 1, is also going to activate SegWit.

The difference is how the activation should happen.

The initial proposal was made by the Bitcoin Core development team. In accordance with the requirements of BIP141, their SegWit code is activated if, for a certain period (approximately two weeks), 95% of the miners are agreed. Taking into account the fact that the consenting miners are really ready to support this update, the risk of a split between the block and the crypto currency of bitcoin will be minimal

However, at the moment only 40-45% of miners gave their consent to BIP141.

Therefore, some Bitcoin users support the activation of SegWit within the softphone BIP148. Since August 1, their nodes will reject blocks that did not signal the support of BIP141. If this proposal is supported by most miners, they will always claim the longest legitimate chain of blocks, which will lead to the activation of SegWit on all agreed bitcoins and will avoid a split. However, if this proposal is supported by a minority of miners, BIP148 may break away from the existing protocol.

The New York agreement, also known as SegWit2x, proposes to activate SegWit according to BIP91. As in the case of BIP148, all BIP91 nodes will reject blocks that did not agree to BIP141. However, unlike BIP148, the BIP91 needs approval of 80% of all miners, which they must confirm within about two days. In this case, the likelihood of a split will also be minimal.

However, the second part of New York implies an increase in the size of the base bitcoin block to 2Mb. This is a hardcore, which unlike the Segregated Witness protocol itself, is not backward compatible, and therefore can also lead to a split.

Here is a list of dates in July, August and the following months, when important events occur.