Читать книгу Blockchain Data Analytics For Dummies - Michael G. Solomon - Страница 34

One way to think of a blockchain is as a big spreadsheet that is shared among many nodes. Each row in the spreadsheet represents a transaction that records amount, from owner, and to owner columns, and sometimes contains columns with additional data. Periodically, a group of rows, called a block of rows, is added to the bottom of each copy of the spreadsheet. You can’t go back and edit any rows in the spreadsheet, but you can add new rows. That analogy is simple, but it gives you an idea of how blockchain transactions are similar to the familiar spreadsheet.

One of the first difficulties in maintaining copies of spreadsheets is how to control adding new rows and protecting existing rows from changes. A full discussion of blockchain integrity is beyond the scope of this book, but following is a high-level overview of how blockchains ensure integrity.