Bitcoin Miners Can Now Signal Support for SegWit

If they so choose, miners can now safely signal their support for a major bitcoin update.

AccessTimeIconNov 18, 2016 at 2:14 p.m. UTC
Updated Sep 11, 2021 at 12:37 p.m. UTC

Bitcoin miners can now show their support for a long proposed technical update that would boost the network's transaction capacity.

Following block 439,488 on the bitcoin blockchain (which occurred at roughly 8:30 UTC today), miners can now upgrade their software by changing a header value in the blocks that they process.

Called Segregated Witness (SegWit), the change is best known as a way to scale transactions on the bitcoin blockchain by carving out more space in each block, though it also solves a long-known major bug and expands the software in a few other notable ways.

As coded in the latest bitcoin software release (0.13.1), 95% of miners need to signal support for the change in a series of 2016 blocks, or a period of roughly two weeks. If that happens, there will be another two week period before SegWit is officially activated.

If activated, the change would ripple out to the rest of the ecosystem of wallets and software projects, and users on the network could begin to take advantage of the update.

But not everyone supports the change (one observer even called the signaling period the beginnings of a "dirty war").

With miners ViaBTC and reaffirming their intent to block the update in recent statements, their combined hashing power (roughly 8%), means there's chance the threshold won't be reached.

On the other hand, other mining pools have shown eagerness to make the upgrade, with Slush signaling support for the change early (despite the alleged dangers of doing so) and BTCC indicating that its mining pool is "ready" for SegWit.

Others may not be technically prepared to make the change quite yet.

F2Pool said in an email that the mining pool cannot signal support in the "near future" because their system isn't upgraded to the correct version of the programming language C++.

Bitcoin Core, the volunteer group behind the most popular bitcoin software, released a graph that shows the total, estimated hashrate flagging support of SegWit at any given time (as indicated by the red line).

According to the coded rules, miners have one year to reach the near-unanimous threshold before the change times out.

Green light image via Shutterstock


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