---
description: (hereinafter referred to as SID)
---

# Decentralized Digital Identity Sun ID

SID is a novel, verifiable identity identifier suitable for the Web3.0 network world. It allows individuals or organizations to fully own, manage, and control their digital identity and data.

SID consists of 1 to 12 digits, and can optionally end with ".btc". Each SID account contains the following abstract structure:

* Owner: The ultimate owner of this SID, who can transfer the account and set the account's administrators.
* Controller: The administrator of this SID, who can manage the Records of the account.
* Registry: The resolution record table of this SID account. Resolution records are a series of key-value pairs defined by users or applications.

**SID features**

* Readability and memorability, such as: 12345 or 12345.btc.
* Permissionless creation process without revealing any personal information.
* Decentralization and censorship resistance.
* Compatibility. SID supports the entire chain ecosystem, deploying not only on current mainstream EVM-based public chains but also on the new-generation Move public chains like Aptos/Sui, thus supporting the Aptos/Sui ecosystem.

**Applications of SID in Web3:**

1. As a cryptocurrency receiving account: Users can add friends via SID and initiate cryptocurrency transfers to them without the need for complex and lengthy addresses, greatly simplifying the cryptocurrency transfer process.
2. As a login credential: In the Web2.0 era, services require account passwords for login. Using the same password for multiple websites poses security risks, while using different passwords for each site incurs high password management costs. Each SID account is associated with at least one pair of public and private keys. Other dapps can sign login operations using the private key associated with the SID.
3. Chain-wide reputation aggregation: Sun Protocol quantitatively assesses users' reputations based on their past behaviors, to determine what level of service to provide. Additionally, in the context of Sun Protocol supporting the entire chain ecosystem, SID can obtain not just the reputation of a user's specific address but the aggregated reputation of all addresses across all public chains.
