How did you feel when Facebook, Whatsapp, and Instagram went down some months ago? Did you panic? Were you anxious or how did you react to the downtime? Did you place a call to friends and families to check if the same happened to them? Was your secret information shared via these platforms stolen by hackers or transferred to a private cloud storage as rumored?

Anyway, the whole world went cold when they could not access their accounts on these platforms.

Do you remember when Facebook was fined £500,000 in 2018 by the UK’s data protection watchdog, owing to the Cambridge Analytical Data Leak scandal when personal data of millions of Facebook profiles were mined without their approval and were used for political purposes?

Do you also remember the attack carried out on one of the major centralized storage systems-DropBox, which affected 68 million users?

All these and other data breaches exposed the weakness of centralized storage, the need to avoid data theft, and the need to adopt a better alternative; a decentralized blockchain solution.

Decentralized Cloud Storage: Why the Need For It?

Since the advent of blockchain technology in 2008, it has witnessed perpetual adoption as an innovative technology due to its endless use cases in various industries. Cryptocurrency—one of the leading financial use cases of blockchain—brought blockchain to the limelight. The key factors that made blockchain the spine of many innovative projects inclined to it is its immutability and distributed/decentralized features.

But first, what is blockchain?

Blockchain is a public decentralized and distributed ledger that stores information chronologically in sets of blocks and links the blocks in a chain-like structure, making it impossible to alter after the information/data has been recorded.

The information recorded on a blockchain is immutable—it can't be hacked or changed; this is why blockchain is a highly secured technology. Blockchain can be likened to a cul-de-sac where information can only be recorded, and there is no exit point.

Though information will be available to every node on the blockchain network once it has been added, it can't be removed or changed.

The decentralized feature of blockchain is its ability to eliminate third parties—government inclusive—and grant transactions to P2P, P2C, and B2B without any interference from an unsolicited entity.

The central aspect of decentralization that grants another layer of security to blockchain technology is its ability to store data or information in a decentralized server where it is not controlled or managed by any central server or giant server provider.

Since blockchain naturally stores information, secures it from being compromised, and maintains the original form of such information, it suffices blockchain enthusiasts to carve out a niche for this feature alone and equip it with the organic requirements of cloud storage.

Cloud Storage

Cloud storage is a data vault where data or digital file is stored on cloud servers owned and managed by third parties. It evolved from cloud computing, which uses internet-based computer services such as software, databases, networking, servers, and data storage.

Any media files like videos, photos, documents/files which can be primarily stored on a storage device or computer hardware, can also be stored on cloud storage. This can be done by transferring or uploading such media files to the cloud storage, where they can be accessed from anywhere with internet access.

What is Decentralized Cloud Storage—DCS?

Decentralized cloud storage is a cloud storage where data or information is stored on a blockchain network. Unlike centralized cloud storage, decentralized cloud storage stores data using the distributed ledger model. In short, the key features of blockchain technology are put to effective use in providing blockchain as an efficient storage medium. The features are:

Peer-to-peer—P2P— network.
Decentralization
Cryptographic Encryption
Immutability

How Are These Features Applicable in the Storage Use Cases of Blockchain?

1. P2P Network

Recall that blockchain is a peer-to-peer technology that allows users to interact or transact with one another without any intermediary. All users in blockchains that offer cloud storage are interconnected via their computers—nodes.

This enables all users to be eligible to lease their unused storage to others and earn cryptocurrency in return. Users who want to store data or files on DCS will have to pay a token, which is paid to the nodes participating in the storage of their files or data.

2. Decentralization/Distribution

This is another essential feature of blockchain technology where data is stored in a decentralized or distributed fashion. Focusing on the distribution aspect, files that are ready to be stored in a DCS undergo sharding, breaking such files into pieces or fragments.

Each fragment is then distributed in multiples across nodes on the blockchain. These multiple distributions are to prevent data loss in case a node is offline. As such, there is no central server for data storage.

3. Cryptographic Encryption

Are you wondering how secure your file will be after being distributed to unknown nodes?

Rest assured that blockchain has your back.

Before data is distributed across nodes, it is usually encrypted cryptographically such that no one can pry into your file. Only the owners of such files have the encryption key. Even if unauthorized people have access to your data, which is nearly impossible, it will be meaningless because such a user is holding a fragment or a piece of a more significant chunk of the file.

4. Immutability

Since it is impossible to pry into your file and access the content, it will be impossible for any nodes to alter or modify the fragment of a file stored on their node. The file is on their nodes for storage purposes only; it'll be useless for purposes other than storage.

Working Principle of Decentralized Cloud Storage

The working procedures of decentralized cloud storage are concise but comprehensive. It is concise that it involves only two processes, and is comprehensive if the processes are examined.

The two concise processes are:

i. Uploading file to a DCS
ii. Downloading file from a DCS

Uploading file to a DCS

Uploading a file to a DCS passes through three stages before it is finally stored.

I. Encryption Stage

The first stage of uploading data or file to a DCS is encryption. All data bits get encrypted automatically to secure your data from prying eyes. Except for you and those you've given access permission to, no one can decrypt and access your file.

Furthermore, you will also have the option to revoke the access permission given to anyone at any time. This means no one can access your data unless they have valid private keys and authorization. Different DCS systems can use different cryptographic algorithms to encrypt data because data stored is usually encrypted cryptographically.

II. Sharding Stage

Sharding is a database fragmentation technique that divides big data into smaller and more manageable fragments. These smaller fragments or components are termed "Data shards." After your file has been encrypted, they are sharded into smaller fragments where each fragment is identical to one another.

Sharding is another layer of security to your file aside from the encryption because different fragments of your file will be sent across different nodes on the ecosystem in different locations. Even your DCS provider is unable to access your file because it has been partitioned into parts that can only be restored with the correct encryption key.

III. Distribution Stage

Every fragment of your file is distributed and stored on randomly selected nodes giving preference to their local response time and reputation. This shows your file is not stored in one central node or server. Data breaches, network downtime, or other difficulties can't affect your data because each file fragment is stored on multiple reliable nodes.

Downloading file from a DCS

Downloading your file from a DCS is not so hard.

It starts with fetching the fragments of your file across all nodes storing them;
Then each fragment fuses to form your original single file;
Then you decrypt the file with your cryptographic encryption key;
And lastly, you download your file.

In case a node is offline when you want to retrieve your file, about 36% of the fragments—depending on your DCS provider—are required to have your original file.

Why Decentralized Cloud Storage?

When it comes to juxtaposing centralized technology with decentralized technology, the advantages of decentralized technology always outshine its centralized counterpart. This is not only because decentralized technology is the latest but because decentralized technology has been developed to address the limitations of centralized technology. Let's consider this by checking the advantages of DCS over Centralized cloud storage—CCS.

Advantages of DCS over CCS

1. Better Security and Privacy

Since CCS providers control the server, they can do whatever they want with your file. They can pry into your file—which is tantamount to breaching your privacy— to either alter, delete, or even steal it from you. Furthermore, CCS is prone to cyber-attacks which can compromise every data on their server.

Unlike CCS, DCS providers can't access your file due to the layers of security architecture. Nobody can change or steal your data or files; thus, they can't be hacked. Due to the anonymity feature of blockchain, it is impossible to trace which file belongs to who, which can make owners be a victim of attack and blackmail. This is not possible with CSS.

2. No Risk of Lost Files

If there's a file transmission error during the retrieval of files, owners can still access their files from other nodes. This is only possible due to the distributed feature of the DCS, which distributes multiple sharded fragments across numerous nodes on the particular blockchain network.

Unlike DCS, once a file cannot be transmitted back to the owner from CCS, probably due to a corrupted file or other related issues, it is lost forever and can't be retrieved.

3. Easier File Uploads and Downloads

DCS uses a P2P protocol that involves numerous nodes that provide more computing power; this enables users to upload and download their files seamlessly without downtime. Unlike CSS, which has a limited computing power to overcome the massive traffic that riddles it.

Conclusion

DCS is blockchain-based cloud storage that doesn't store files or data on a centralized server. Instead, data is stored using the distributed ledger protocol by distributing fragments of uploaded files across the nodes participating in its ecosystem. DCS has proven to solve the flaws of centralized cloud storage, which is not entirely secure and not privately oriented.

Notable DCS include:

Bittorent (BTT)
Filecoin (FIL)
Akash Network (AKT)
Siacoin (SC)
StorJ (STORJ)
Qitchain (QTC)
Internxt (INXT)

Photo by Dallas Reedy on Unsplash