Why Bitcoin?
ATP uses Bitcoin as its anchor. This is a deliberate design choice, not just a technical preference.
The Requirements
For permanent, verifiable identity, we need a ledger that is:
- Immutable — Records can't be changed or erased
- Censorship-resistant — No one can block your transactions
- Permissionless — Anyone can participate without approval
- Timestamped — Clear proof of when something was created
- Decentralized — No single authority controls it
- Durable — Will exist for decades to come
Bitcoin is the only blockchain that meets all these requirements at once.
Why Bitcoin Specifically?
Immutability
Once a Bitcoin block is confirmed, it's effectively permanent. The computational power required to rewrite history grows exponentially with each new block. Your identity, once inscribed, can't be erased.
Censorship Resistance
Bitcoin's distributed network of nodes means no single entity can block your transaction. If one miner won't include your inscription, another will. Your identity can't be censored.
Timestamping
Every Bitcoin block has a timestamp. Once your identity is confirmed in a block, you have cryptographic proof of when it was created. This is useful for establishing precedence and audit trails.
No Central Authority
Bitcoin has no CEO, no company, no board of directors. It's governed by consensus rules enforced by the network. This means:
- No one can change the rules to invalidate your identity
- No one can shut down the network
- No one can ban you or revoke your access
Battle-Tested Security
Bitcoin has operated continuously since 2009 — longer than any other blockchain. It has:
- The largest network of nodes (tens of thousands)
- The most mining power (making attacks prohibitively expensive)
- The longest track record of security and uptime
If you want your identity to last 50 years, you want it on the blockchain most likely to still exist in 50 years. That's Bitcoin.
Cost as Spam Prevention
Inscribing data on Bitcoin costs satoshis (small fractions of a bitcoin). This small cost is a feature, not a bug:
- Prevents spam — Creating millions of fake identities becomes expensive
- Signals commitment — Paying to inscribe shows you're serious
- Economic incentive — Miners process your transaction because you pay them
The cost is low enough to be accessible (typically a few cents to a few dollars), but high enough to deter abuse.
Why Not Ethereum (or Other Chains)?
Other blockchains have different tradeoffs:
Ethereum
- More complex (smart contracts add attack surface)
- Higher transaction costs (historically much higher than Bitcoin)
- More centralized governance (Ethereum Foundation, EIP process)
- Younger and less battle-tested
Solana / Other High-Performance Chains
- Less decentralized (fewer nodes, higher hardware requirements)
- Less proven long-term durability
- More governance risk (foundation-driven development)
Private/Permissioned Chains
- Defeat the entire purpose (centralized control)
We chose simplicity, durability, and decentralization over features we don't need.
The Inscription Method
Bitcoin doesn't natively support arbitrary data storage, but it has multiple ways to embed data:
- OP_RETURN (80 bytes, prunable)
- Taproot inscriptions (unlimited data, more efficient)
- Legacy methods (less efficient)
ATP uses Taproot inscriptions — data is embedded in the witness of a Taproot script-path spend, making it permanent and self-contained. The specifics are in the technical spec.
Tradeoffs
Bitcoin isn't perfect for this use case. The tradeoffs:
Slower confirmations — Blocks every ~10 minutes means you wait for finality. (Explorers can index unconfirmed transactions for faster UX.)
Transaction costs — You pay for each inscription. Costs vary with network demand. (Usually $1-10, sometimes higher.)
Limited throughput — Bitcoin can't handle millions of identities per second. (That's okay — identity creation isn't high-frequency.)
We accept these tradeoffs because permanence and censorship-resistance matter more than speed.
The Result
By anchoring identities on Bitcoin, ATP provides:
- ✅ Permanent, immutable records
- ✅ Censorship-resistant identity creation
- ✅ No central authority or gatekeepers
- ✅ Cryptographic timestamps
- ✅ Maximum durability and security
Your identity will outlast any company, any platform, any trend. As long as Bitcoin exists, your identity exists.
Next Steps
- Core Concepts — Learn about identities, attestations, and receipts
- How It Works — See the technical process step-by-step
- Quick Start — Create your first identity