Bitcoin Miners Are Submitting Coinbase Rewards From Other Blockchains Onto Bitcoin

Image result for bitcoin mining dribbble
Image result for bitcoin mining dribbble

How is This Happening?

As stated above, this is occurring via a process called ‘merged mining’, through which certain large mining pools have been able to submit blocks from other chains to the Bitcoin blockchain in order to effectively claim the block reward without completing the requisite amount of work.

The explanation of this requires a technical knowledge of Bitcoin down to the mechanisms that underpin how it works.

Long story, short - UTXO verification rules apply to every aspect of Bitcoin but coinbase rewards. Coinbase rewards are newly generated transactions, the typical verification process (i.e., checking to ensure that the spent outputs match up with the inputs & tracking the history of the UTXO through to the actual coinbase itself).

These transactions also take advantage of the signature separating framework of SegWit.

Using AuxPow, such a process of ‘gaming’ Bitcoin has been taking place using altcoins, ‘Devcoin’ and others.

Example of This Taking Place

Here is an example one of the ‘merged mined’ transactions that can be correlated directly to Bitcoin: https://chainz.cryptoid.info/dvc/block.dws?389160.htm

Below are photos displaying the details of the raw block:

The TX ID in the block header (depicted above) for ‘Devcoin’ can also be found on the Bitcoin blockchain itself (for the coinbase transaction of block height 593182)

Refers to this Bitcoin transaction (Coinbase TX).

SegWit TX though - nonstandard.

Didn’t even know that Coinbase TXs could be SW until I saw these kinds of TX.

TX ID = 541490f82e7903e474d5b2f04c8ddb4ed878a9783fe2175e1eb1a546567ed224

URL = https://blockchair.com/bitcoin/transaction/541490f82e7903e474d5b2f04c8ddb4ed878a9783fe2175e1eb1a546567ed224

In addition, the other relevant transaction/block header details for the coinbase transaction on Bitcoin’s blockchain that were mentioned before can be found in the Devcoin block header as well:

What’s even more unique about the transaction above is that it is a ‘merge mined’ SegWit (Segregated Witness) transaction done via ‘AuxPoW’.

Further Evidence

If we go ahead and take a look at the relevant block header data on btc(.)com, we’ll see the following:

Source: https://btc.com/541490f82e7903e474d5b2f04c8ddb4ed878a9783fe2175e1eb1a546567ed224

Words like “commitment hash” exist in reference to SW conventions.

More Information on Merged Mining + SegWit Specifications

This process is rather vague, hasn’t really been discussed since Namecoin was popular.

SegWit is also poorly understood

Here are some reference links:

  1. Bitcoin Wiki Merged Mining Specification = https://en.bitcoin.it/wiki/Merged_mining_specification

  2. BIP 141 = https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki

  3. BIP 143 (TX sig verification for version 0 witness program) = https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki

This is what the TX information looks like for the first merged mined block (on Namecoin, notably)

https://bchain.info/NMC/tx/88afdfdcc78f778f701835b62e432d3ba7d55b3e59ac4e7cab08d6bc49655c0f

Looking Back at Devcoin (Very Strange Occurrence)

If we go back to the block header data for the block that was isolated for ‘Devcoin’, the following can be observed:

Above are the isolated UNIX timestamps for both Bitcoin and Devcoin in the Devcoin block header.

Parent Chain = Bitcoin

Child Chain = Devcoin

UNIX Timestamps

Parent Chain (Bitcoin) = 1567583091

Child Chain (Devcoin) = 1567582925

Converting the UNIX Timestamps to MM/DD/YY 00:00 Format

Below is the converted UNIX timestamp for the parent chain (Bitcoin):

Below is the converted UNIX timestamp for the child chain (Devcoin):

Notably the timestamp for Devcoin comes a full two minutes before Bitcoin’s, yet it still contains all of the relevant information for Bitcoin within the timestamp (including the actual timestamp of the next Bitcoin block).

How is This Possible?

The author(s) of this post have absolutely no clue, but it is something that should be clarified by the lead developers of Bitcoin (as well as Devcoin), especially in light of the relative lack of documentation surrounding ‘merged mining’.