What's new in version 2 of Block header message ?

[Yves Cuicui]

The version field in block header message is now '2'.
Does someone know what is the difference compared to version 1?
Thanks

[Peter Todd]

Read this: https://en.bitcoin.it/wiki/BIP_0034

[Yves Cuicui]

Many thanks

[fpgaminer]

95% rule ("Point of no return"): If 950 of the last 1,000 blocks are version 2 or greater, reject all version 1 blocks. (testnet3: 75 of last 100)

Are we here yet on mainnet?

[joshlang]

Yeah - At block 227930, the previous 1000 contained the supermajority of 950.

[fpgaminer]

Yeah - At block 227930, the previous 1000 contained the supermajority of 950.

Very cool    Thank you for taking the time to look that up.

[Yves Cuicui]

Anyway, this is not an information we can rely on.

I notice many blocks pretending to be version 2 but showing bad height encode values

See
http://blockexplorer.com/block/00000000000005d024e86337ca13439b7f3dbd5e1a005b1dbe510150d45b6e98 is block 200433 and pretends to be 436591499
http://blockexplorer.com/block/00000000000003c6947e260dc80d6ab426771a7ba9d8d5fb58ff66a0db26c361 is block 199914and pretends to be 436591499

May be such blocks must not be accepted by the network as the BIP34 is now enforced?

[kjj]

Anyway, this is not an information we can rely on.

I notice many blocks pretending to be version 2 but showing bad height encode values

See
http://blockexplorer.com/block/00000000000005d024e86337ca13439b7f3dbd5e1a005b1dbe510150d45b6e98 is block 200433 and pretends to be 436591499
http://blockexplorer.com/block/00000000000003c6947e260dc80d6ab426771a7ba9d8d5fb58ff66a0db26c361 is block 199914and pretends to be 436591499

May be such blocks must not be accepted by the network as the BIP34 is now enforced?

Early on, there was some debate about the proper encoding.  See this discussion for information on why the bogus encodings were allowed (specifically a post from gmaxwell on July 2nd).

[Yves Cuicui]

Do you mean that some miners start building v2 blocks on main network while the debate was not closed?

[kjj]

For something like this, a supermajority of miners have to move in lockstep, or there is risk of forking.

[joshlang]

Anyway, this is not an information we can rely on.

I notice many blocks pretending to be version 2 but showing bad height encode values

See
http://blockexplorer.com/block/00000000000005d024e86337ca13439b7f3dbd5e1a005b1dbe510150d45b6e98 is block 200433 and pretends to be 436591499
http://blockexplorer.com/block/00000000000003c6947e260dc80d6ab426771a7ba9d8d5fb58ff66a0db26c361 is block 199914and pretends to be 436591499

May be such blocks must not be accepted by the network as the BIP34 is now enforced?

After block 227930, it's information you can rely on.