Account
Signum uses an account-based model:
- Each transaction is created on behalf of a particular account.
- All smart tokens belong to specific accounts.
- All data is associated with accounts.
- Smart Contracts are also account based.
- The Zero Account (0) is the burn account for the Signum blockchain.
Unlike centralized applications, users do not have usernames and passwords on the blockchain. User identification and validation of their actions are performed using a cryptographically bound key pair:
- The private key is used to sign transactions or orders.
- The public key is used to verify the digital signature.
Each transaction contains the public key of the sender account. The sender generates a digital signature of the transaction using the account's private key. The signature and the sender's public key are used to verify the authenticity of the transaction data and to check that the transaction's signature matches the public key.
Signum uses an asymmetric cryptographic system based on the elliptic curve Curve25519-ED25519 with X25519 keys.
The private and public keys are 32-byte arrays. In UIs, the keys are displayed as base58 (opens new window) encoded strings. Base58-encoded keys can be of different lengths, and the maximum size is 44 characters.
The private key can be generated using hashing functions from some random seed phrase. The public key is obtained from the private key using an elliptic curve multiplication. An account address is obtained from the public key. All these transformations are unidirectional. To perform this transformation in the opposite direction is almost impossible regarding the required computations.
The secret phrase (a.k.a. seed phrase, backup phrase) can be any combination of symbols, words, or bytes. Signum wallet apps typically use a random set of 12 to 15 English words out of 2048 words available. Using such a phrase is secure: the probability of generating two identical seed phrases is 1/204815, so the brute force will take millions of years on an average CPU. The point of using a secret phrase (rather than a private key) is to simplify user experience: the secret phrase is much easier to write down or remember.
Example of a secret phrase:
roll fold shade creek join peach clear wipe paper women bottom broken t-shirt
- The secret phrase provides complete control over the account, including the ability to dispose of the funds. Please do not give your secret phrase to anyone, and do not publish or send them.
- The secret phrase cannot be changed: another secret phrase (even one that differs by a single character) will generate a different key pair and, therefore, a different account.
- If you lose your secret phrase, you can no longer access your account permanently. We strongly encourage you to write the secret phrase on paper and store it safely.
- If the secret phrase is compromised (you have accidentally sent it to someone or suspect that fraudsters took it), immediately create a new account and transfer all Signa balance, assets and aliases to it.