Append Only Blockchain
A key feature of blockchain’s data structure and information addition process is “Append-Only.”
Meaning: The data structure used by the blockchain is append-only. This implies that the blockchain is the sole place where data can be added. Data that has already been captured cannot be altered or removed.
How Data is Added: The chain can only include verified blocks. The order of this addition is time-sequential. The blockchain network verifies the blocks in a sequential sequence before adding them.
You can also read What Is P2P In Blockchain? Its Key Features And Advantages
Mechanism for Enforcement: Because every newly added block must make reference to the hash of the prior block, the append-only nature is ensured. Using these hash references, blocks are “chained” together. To guarantee this immutability, a representative signature value of block ‘n’ is kept in block ‘n+1’.
You can also read What Is The Drawback Of Blockchain Technology?
Consequences and Benefits
- Immutability: This feature guarantees that a block cannot be changed once it has been uploaded to the network. Since it is nearly hard to change data, it is regarded as essentially unchangeable.
- Tamper Detection: The hash value of a block will alter if a malevolent actor attempts to access or alter the data within it. The fundamental operation of the network’s block chain will be disrupted by this modification, making it simple to identify. Because of this, the ledger is impenetrable and tamper-evident.
- Complete History: Because the blockchain database is append-only, it keeps track of every asset and instruction that has been executed since the first block, also known as the genesis block. The whole record is maintained since data is only ever added.
Fundamentally, one of the main reasons blockchain is regarded as a distributed immutable record that fosters participant confidence is its append-only architecture, which is protected by cryptographic hashing and upheld by consensus procedures.
You can also read Blockchain Trust Layer: How Decentralization Create Security
Tamper Evident and Tamper Resistant
Blockchain ledgers are more precisely and rigorously referred to be tamper evident and tamper resistant, even if they are occasionally called immutable. They are trusted mostly because of this attribute, especially when it comes to financial dealings.
Tamper Evident: This indicates that changes to the data are simple to identify. Cryptographic hashing and the append-only structure make blockchain tampering obvious. If a malicious actor tries to access or alter the data in a block, the hash value of that particular block will change since each block contains the hash of the preceding block. Because the stored hash of the subsequent block will no longer match the new hash of the changed block, this change in the hash value will subsequently disrupt the fundamental operation of the network’s chain of blocks. The modification is clearly observable due to this interference.
Tamper-Resistant: This indicates that changing the data is either expensive, complex, or both to do. The blockchain is immune to tampering because consensus is reached throughout the dispersed network. Modifying a previous block would necessitate not only recalculating the hashes of that block and all subsequent blocks (due to the chaining effect), but also gaining control over a majority of the network to enforce the altered version as the accepted truth.
This is because data is distributed and a copy frequently exists on many participating nodes. As demonstrated by Proof of Work, this frequently calls for a large amount of processing power, making the work both technically challenging and financially expensive. Because of this, it is nearly hard to change data after it has been put to a working blockchain.
The distributed, consensus-driven network and cryptographic hashing make the recorded data both tamper-resistant (changes are difficult or expensive to make) and tamper-evident (changes are discovered), essentially dictating how data is added (just at the end).
You can also read What Are The Different Types Of Blockchains Technology?