Decentralized Databases: Advantages & Disadvantages of Decentralized Database Systems

As the world becomes more and more connected, it is becoming increasingly important to store data in a way that is secure and efficient. A decentralized database system allows for multiple users to access the same data without having to share information with each other, which makes it an ideal solution for businesses that need to keep sensitive information confidential. However, there are also some disadvantages to using a decentralized database system. In this article, we will discuss the advantages and disadvantages of decentralized database systems so that you can make an informed decision about whether or not a decentralized system is right for your business.

What is a Database?

A database is generally assumed to be anything that has the capability of storing data. However, it can also be defined by query capabilities. It considers factors such as if it can retrieve data sets from a whole, the data size, if it is structured or unstructured, etc. 

What is a Decentralized Database?

A decentralized database refers to splitting the workload between several machines and using a sophisticated algorithm for all its incoming and outgoing requests. It is used in scenarios that need data storage within a database rather than what is possible on a tangible piece of machinery.

Decentralized database vs. Distributed database

Often, people confuse the two terms to be the same thing. While similarities do exist, there is a vast contrast between the two. Decentralized and distributed databases deal with multiple servers, and the likelihood is that these will be located across several areas. But, that’s all that lies similar. 

In a distributed system, data is effectively split, and all the processing takes place amongst the different nodes of a cluster. It takes place in such a manner due to the trust established between all the nodes. There is either an internal list present with all the cluster nodes, or there is reliance on a central authority that monitors all information flowing through.

In a decentralized system, all nodes share data amongst themselves without knowing what’s on the flip side. An underlying technology powers the clusters for this process. The built-in fault tolerance makes the network consistent and secure in case a node gets compromised.

4 Key Properties of a Decentralized Database

There are certain factors that influence what makes a decentralized system function the way it does. For example, determining the “true” copy, the node to copy on is it feasible to maintain an independent copy, etc. Each factor makes up for different properties that run the system. For a decentralized system, here are the key properties that make it a stable system.

1). Offline first 

A decentralized system means that you should have the ability to create a new instance or node. You should also have a copy you can write or read whenever needed. Offline first reduces the levels of network dependency, allowing you to create a “fork” by leaving the system at any point in time. It also reduces the need for a central authority to do reads and writes. Offline first is the main factor that makes a system “decentralized.”

2). Sharing 

Offline first makes a file decentralized but is insufficient to act as a system. To do so, any instance or node created is required to communicate with other instances or nodes to form a functioning system. Different models of sharing are used as a part of decentralized database systems. 

3). Fault-tolerant 

A decentralized software can often assume the appearance and disappearance of nodes without warning. The modes may sometimes produce stale writes or data that can interrupt the operations of a database. Hence, decentralized systems are made with the help of architecture that maintains a list of all active nodes. It helps reduce the risks of any failure, and if one does occur, it is more convenient to identify what has gone wrong and rectify it due to the system’s ability to maintain node history. 

4). Trustless

It is slightly different from fault-tolerant, which calls for system designs to be resistant to faults. The trustless feature can tackle malicious or rogue nodes that may corrupt the entire system. A decentralized system means that you will not have control of all nodes. To prevent breaches, using cryptography can help make the system more secure and identify users who may not be a part of the database. 

3 Key Uses of a Decentralized Database

• Data replication: A decentralized database can duplicate data across the running network. There may be variations in the implementations, but for the most part, each node carries the entire database. It is beneficial as since the nodes are distributed, it is possible to have very low latency to serve clients with the fastest nodes.

• Data security: Decentralized systems carry an intrinsic “vetting” feature, which ensures that any data entered into a node is vetted by the network before any distribution takes place. It prevents the disruption of the network on a global scale in the unforeseen event of a node getting compromised. The feature helps remove common vulnerabilities one may come across.

• Global stability: The architecture of a decentralized database is less prone to errors than that of a distributed system. Because of the central authority present, a single failure can render the whole cluster to become unusable. With decentralized systems, no central authority controls the processing of data. If a single node fails, the rest of the system can still run, thus providing higher levels of stability for those who use a decentralized database.

Decentralized Database Models

Based on the key factors of decentralized systems, there are three models that we can come across, namely blockchains, peer-to-peer, and Git.

• Blockchains: It is one of the most popular models of the decentralized system, with over a thousand public blockchains in the market. It is an offline first system, which means that you can read and write onto a copy, or even initiate your own separate block with the same software. Blockchains make use of transaction and identity verification to achieve fault tolerance and trustlessness. Transactions are made using cryptographically proven identity so that all activity can be linked to one. The downside of Blockchains is their vulnerability to be taken over by rogue nodes. If a malicious user can get enough nodes to accept your new state as the truth source, then it is possible to shift the functioning of a chain. In order to prevent this, blockchains defend nodes through scale. The more nodes that are included in a blockchain system, it can become more fault tolerant and trustless. 

• Peer-to-peer: It is a decentralized system that gained popularity in the 1990s. It was a means for people to share music with one another, and ultimately share media all over the internet. It enabled sharing of copyrighted material, which meant owners could only resort to suing for damage. BitTorrent is a popular example of such a system, along with Dat and IPFs for databases. In peer-to-peer systems, each node inside carries a subset of data locally stored on a device. It is an offline first system, which means that you can read or write data onto nodes without having an internet connection. To prevent malicious attackers, the system does so by being append-only. 

• Git: It is a popular decentralized system that is often used for the purpose of version files. It was developed by Linus Torvalds, the creator of Linux, in 2005. In this decentralized model, each node carries file copies and the history of each of them. It is possible for nodes to create reads and writes of any past revisions. In the event that a node wants to share any change, it creates a “remote”. It then sends a “push” or receives a “pull”. The Git model is designed to calculate differences between all existing versions. By separating remotes from each node, the model can achieve fault tolerance and trustlessness. In the event of a node getting corrupted, it is possible to restore a previous state to a new remote. You can rely on copies present on other nodes to retrieve data in case of loss. The Git model requires trust to be present but not completely compared to blockchain models. 

Decentralized Database Options

• BigchainDB: It attempts to combine the world of blockchain with database systems, thus giving a decentralized approach for all data storage needs. It was launched in 2016 and has become a stable alternative to MySQL. It provides high throughput, low latency, and built-in asset support as well. 

• HarperDB: It offers the option of hybrid storage so you can have a setup where remote devices only worry about sending queries, and the databases take care of synchronizing data in the clusters. Because of the mechanisms provided, users can sync data across the globe and have their local devices maintain millisecond-level low latency for data needs. 

• CovenantSQL: It is a new alternative that advertises itself as an open-source option compared to AWS’s QLDB. It aims to be a decentralized and SQL-backend database for any requirement.

7 Advantages of a Decentralized Database System

• System expansion: Since a decentralized database system is spread across several machines, it is more convenient to expand them as and when needed. Users may add a new part to the system for expansion without forming any complications.

• Transparent storage: Data stored in a decentralized database may have different transparency levels. Users can store it across multiple locations depending on the various levels attached for better security and accessibility. 

• Hierarchical organization: Due to the decentralized approach, users can store data department-wise, depending on an organization’s needs. It makes it more convenient to set accessibility for different hierarchical levels of the organization. 

• Data safety: Since the decentralized database system involves data storage on multiple machines, data will remain safe if a natural calamity hits and affects one part of the system.

• Cost-effective to build the system network: Creating a network of systems that carries database parts is also convenient and cheaper. Networks can be made depending on the need to increase or decrease parts of the database.

• Offline availability: The decentralized database system can make data available even if some nodes go offline. It can also carry on with its normal functions in such a case. 

• Better reliability: Because the system is distributed, data is available at different points for accessibility. It is more reliable to use when necessary to view and act on different data.

7 Disadvantages of a Decentralized Database System

• Complex for uniform views: Since a decentralized database is spread across multiple machines, it is often a complex process to ensure that each user can access a consistent view of all the data available through the database. 

• Expensive to maintain: A decentralized database can be costlier to take care of due to its vastness. Maintaining all the machines involved across multiple locations can be costly for any business. 

• Difficult to keep secure: Providing security to a decentralized database can be challenging since it is spread across many locations. It is necessary to ensure that all machines have the same level of secureness, which may prove expensive when covering a vast system. 

• Data integrity is complex: With a decentralized system, maintaining data integrity can be challenging as there is a chance that redundancy may arise in several parts of the database in other locations. 

• It is hard to find the right people to manage: Since a decentralized database is vast and spread across different machines and locations, managing it can be difficult. Finding the most suitable people with experience to monitor the database may not always be possible. 

• Different data formats: The database may store several formats, which may cost valuable time when looking for specific requirements for any business activity.

• Complex design: The database system can be complex as it has to consider fragmentation, allocation, and possible duplication of all stored data. It may increase the risk of miscommunication or missed data.  

Endnote

Decentralized database systems work across multiple machines and are accessible to involved parties who need to act on any data stored. They are different from distributed systems but can be included as a class of them. In a decentralized database system, nodes share data amongst themselves. But it has the downside that each node can be owned by an untrusted party. While they may be complex systems to build, secure, and monitor, the availability of advanced technology and software makes them more reliable. For example, the Blockchain decentralized system makes use of cryptography to make networks more secure. It ensures that all parties involved are verified before any data is passed on or distributed.