What s the difference between distributed hashtable technology and the bitcoin blockchain

0 votes
This question could go into a bitcoin forum but I am trying to understand it from a programming point of view.

There are technologies used for distributed storage, like distributed hashtables. How is the bitcoin blockchain different from distributed hashtables? Or is maybe distributed hashtable technology underpinning the bitcoin blockchain? Or why is the bitcoin blockchain hailed as such a breakthrough compared to DHT?
Apr 6 in Blockchain by Aditya
• 7,280 points
24 views

1 answer to this question.

0 votes

A Distributed Hash Table is simply a key-value store distributed across a number of nodes in a network. The keys are distributed among nodes with a deterministic algorithm. Each node is responsible for a portion of the hash table.

A routing algorithm allows performing requests in the hash table without knowing every node of the network.

For example in the Chord DHT —which is a relatively simple DHT implementation— each node is assigned an identifier and is responsible for keys that are closer to its identifier.

Imagine there are 4 nodes that have identifiers: 2a6c, 7811, a20f, e9c3 The data with the identifier 2c92 will be stored on node 2a6c.

Imagine now that you only know node 7811 and you are looking for the data with the identifier each.

You ask node 7811 for the data each. 7811 doesn't have it so it asks the node e9c3 which sends it to node 7811 which sends it back to you.

A clever algorithm allows finding data in O(log(N)) jumps. Without storing the entire routing table of the network (the addresses of each node). Basically, you ask the closest node to the data identifier you know which itself asks the closest node it knows and so on reducing the size of the jump at each step.

A DHT is very scalable because the data are uniformly distributed among nodes and lookup time generally grows in O(log(N)).



A blockchain is also a distributed data structure but its purpose is completely different.

Think of it as a history, or a ledger. The purpose is to store a continuously-growing list of records without the possibility of tampering and revision.

It is mainly used in the bitcoin currency system for keeping track of transactions. Its property of being tamper-proof lets everybody know the exact balance of an account by knowing its history of transactions.

In a blockchain, each node of the network stores the full data. So it is absolutely not the same idea as the DHT in which data are divided among nodes. Every new entry in the blockchain must be validated by a process called mining whose details are out of the scope of this answer but this process ensures consensus of the data.

The two structures are both distributed data structures but serve different purposes. DHT aims to provide an efficient (in terms of lookup time and storage footprint) structure to divide data on a network and blockchain aims to provide a tamper-proof data structure.

answered Apr 12 by Soham
• 8,730 points

Related Questions In Blockchain

0 votes
1 answer

What is the difference between Blockchin and Bitcoin

Blockchain has potential beyond Bitcoin and cryptocurrency. ...READ MORE

answered Jul 13, 2018 in Blockchain by shweta
• 440 points
776 views
0 votes
1 answer

What's the difference between ethereum and chain?

Ethereum is an open source blockchain platform ...READ MORE

answered Sep 12, 2018 in Blockchain by Perry
• 17,100 points
205 views
0 votes
0 answers

What is the difference between blockchain performance and blockchain scalability?

I really don´t get the difference between ...READ MORE

Apr 4 in Blockchain by Soham
• 8,730 points
8 views
0 votes
1 answer

Protocols used in a distributed/dlt system for the nodes to establish communication

yes all are over TCP/IP connections secured by TLS encryption in hashgraph architecture-hashgraph, ...READ MORE

answered Aug 6, 2018 in Blockchain by aryya
• 7,440 points
598 views
0 votes
1 answer

Truffle tests not running after truffle init

This was a bug. They've fixed it. ...READ MORE

answered Sep 11, 2018 in Blockchain by Christine
• 15,790 points
918 views
0 votes
1 answer
0 votes
1 answer

SHA256 Hash doesn't match the one listed on Bitcoin Wiki

The problem occurring here is that you ...READ MORE

answered Feb 28 in Blockchain by Soham
• 8,730 points
41 views
0 votes
1 answer

How can merkle trees help validate the content of a block in a blockchain

As long as they are centralized entities ...READ MORE

answered Feb 28 in Blockchain by Soham
• 8,730 points
63 views
webinar REGISTER FOR FREE WEBINAR X
Send OTP
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP