# Why does pool latency matter?

I often read about latency and ping. I am programmer and I understand what latency and ping is. But I do not understand why miner can't process block with certain delay. Why do 10ms or 100ms matter?

## 1 Answer

Latency of connections between nodes matters when mining because, essentially, a valid block found that reaches the highest number of peers first wins that block height.

For example, if miners Alpha and Beta both find within a few milliseconds of each other, their incentive to push that block around to connected clients as quickly as possible is that they get their block on the chain first and thus are able to claim the reward.

More technically, if we're currently at block height 10, and miners are hashing to find a solution that will become block 11, and Alpha and Beta both find a block, they can both claim it to be block 11. However, it only actually becomes block 11 when 51% of nodes believe that a certain block is the 11^th block. The other block, the valid block that lost the exposure contest, becomes an orphaned block, and gets pruned when the height 12 blocks start coming in.

• I thought every miner process its own small sub block. Or you mean that when I find solution then when I ask to confirm it then someone will tell that it is his own block (to steal it) and if he will be on faster network then he has chance to reach 51% faster then I. – Max Jan 28 '14 at 21:08
• When your miner mines a block, you embed your reward address inside the block (and that is included in the data that is hashed). So other miners can easily verify the block, but they can't change the reward address without mining the whole block again. – Greg Hewgill Jan 28 '14 at 21:25
• So there are 2 miners that do exactly same job? I thought every miner has its own sub-block. – Max Jan 28 '14 at 21:50
• There is no such thing as a "sub-block". When mining in a pool, the pool lies about the real difficulty and makes it easier, to give all the workers a chance to find something (that way, the pool can estimate the amount of work your worker is doing). All workers mine complete blocks. – Greg Hewgill Jan 28 '14 at 23:41