# Storage

We are using Merkel Trees to store address books securely onchain which focuses on verifiability as Merkel trees are know for being verifiable by generating Merkel Proofs

Storage structure looks something like this:

<figure><img src="/files/95rlFd2SkCjPQYCACJ3g" alt=""><figcaption></figcaption></figure>

The above diagram is for a single address book and a list of Merkel root and respective IPFS/Arweave content identifiers will be stored on-chain with respect to an address or identity.

Address books can be fetched from any off-chain and can be verified against Merkel root stored on-chain, this gives the ability to users for verifying the truthness of the books themselves and not depend on any third party.

Even, applications like wallets and conversation apps can verify received address books themselves on behalf of the user and make sure that user is not served incorrect data.

**Who updates the Merkel root?**

Owner / Users can themselves update the Merkel root of their address book but right now as we are still experimenting with our systems, only whitelisted address can update the Merkel root and we will slowly open up the access for users.

**Encryption**

Encryption is very important in address books as users don't want to make their contact list publicly available.

We use asymmetric cryptography to encrypt address books before storing them on public storage solutions like IPFS and Blockchain


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