Hashes & Merkle Trees in Blockchain Mechanics

Hash Functions take input of any length and produce a fixed-length string which means that one can use hashes on something as small as a few characters or as large as an entire document or even files of huge sizes in GBs and above. 

On the other hand enabled by these hash functions, Merkle tree represent hash-based data structure that is a generalization of the hash list and represent structure in which each leaf node is a hash of a block of data, and each non-leaf node is a hash of its children. Both Hash functions and Merkle Trees are cardinal to the mechanics of any Blockchain. 

This video focuses on a simple explanation of understanding Hashes and Merkle Trees. Hash functions SHA-256 and RIPEMD-160 have been discussed in little detail being peculiar to Bitcoin blockchain.

Technology amalgamations inside Blockchain

Blockchain is an amalgamation of multiple technologies which have existed already in the IT ecosystem for last few decades. These include majorly cryptography, private-public keys, hashes, proof-of-work and other important technologies. This video post only identifies by name of what major technologies any blockchain is enabled on.

I want to learn Blockchain, but where do I start from? : Here is My Answer.

I am writing this one exclusive post for guys who just wish to begin their journey in the domain of Blockchain. "Blockchain" term has been buzzing across academia, universities, corporate industries and every where around. In most of the webinars I speak in, I find many inquisitive learners willing to jump in the domain but unable to find that exclusive blockchain sea where to dive in. And if ever they try diving in, the sheer amount of books, videos and sea of information existing on the internet just splashes their visions soon to drown. Herewith I am sharing few slides that are based on my journey in this domain for now over 5 years. The presentation brings out details of topics one should start exploring and dig in followed by few books that I have in person followed and imbibed from.

How to Start Learning BLOCK... by Anupam Tiwari

SPLIT LARGE FILES INTO SMALLER PARTS & MERGE : FOR EASY MIGRATION in LINUX SYSTEMS

1.    Routine troubleshooting in system handling gives us a way to explore and try new options.Recently tried a new way to migrate large files(around ~17 GB in my case here ). Although there are easier options available by simply copying in a external device,but in my case external devices were not allowed so attempted to split the large file into 3 GB size files and then finally could merge them....and could also verify the hash....and it was absolutely right...sharing few screen shots :

2.    The entire thing of splitting and merging gets over in simple two commands of SPLIT & CAT

 > split -b file.name
 > cat x* > file.name

3.   I have a .vdi virtual image file which is approx 16 GB in size.The file details are seen in the screen shot below :

Here ..before I go for the split...I have taken the hash of the same to compare it later after i merge the split parts...to check the originality of files and I get the hash of the file as bb867749cf4c0325abe145a0998e3b04

 

In the screen shot below I use the split command,which is inbuilt to UBUNTU and typically all Linux systems....I split the file in 3GB parts...

 

This screen shot shows the watch screen shot of the populating split parts...

 This screen shot shows the watch screen shot of the populating split parts...

 and here i get the final .vdi file as well m able to match the hash as same ie bb867749cf4c0325abe145a0998e3b04

BLOCKCHAIN TECHNOLOGY OVERVIEW & CRYPTOCURRENCY CRIMES: CBI ACADEMY

Sharing this presentation here in this post that brings an exhaustive overview of the Blockchain Technology and emerging Cryptocurrencies crimes.The presentation was given at CBI Academy on 16 Nov 18 by self :

   BLOCKCHAIN TECHNOLOGY OVERVIEW & CRYPTOCURRENCY CRIMES by Anupam Tiwari on Scribd

BITCOIN FORENSICS AGAIN : Bsides Delhi 2017

1. I have been on a spree like something giving presentations in the domain of BITCOIN FORENSICS for past few months...and more or less talking discussing around the same terms of references but to a new audience always though.Recently participated at Bsides Delhi. Security BSides is a community driven framework for building events by and for information security community members. These events are already happening in major cities all over the world!

The idea behind the Security BSides Delhi is to organise an Information Security gathering where professionals, experts, researchers, and InfoSec enthusiasts come together to discuss. It creates opportunities for individuals to both present and participate in an intimate atmosphere that encourages collaboration. It is an intense event with discussions, demos, and interaction from participants. It is where conversations for the next-big-thing are happening.

2.  Details on the event and about me at https://bsidesdelhi.in/anupam-tiwari/

BITCOIN FORENSICS : Bsides Delhi Conference from anupriti

BITCOIN FORENSICS : ROAD AHEAD

Gave this presentation and talk on the still evolving field of BITCOIN FORENSICS that brings out the technical overview and evolving forensics developments in the domain at the BLOCKCHAIN SUMMIT held at BrightTalk on 10th Oct 2017 vide webinar

Webinar on BITCOIN FORENSICS : BRIGHTTALK from anupriti

More Details at https://www.brighttalk.com/webcast/13689/272431/bitcoin-forensics

BITCOIN FORENSICS : CHALLENGES & HOPE

Gave this presentation and talk on the still evolving field of BITCOIN FORENSICS that brings out the technical overview and evolving forensics developments in the domain at the "4th  International Information Security Meet “ Hakon’2017, Insecure Cyber of Things – The Hackers Choice" held at Indore,MP.

BITCOIN FORENSICS : HAKON-2017 CONFERENCE from anupriti

BITCOIN is FOREN"SICK" : Threats and Solutions

1.  The increased use of cryptocurrencies such as Bitcoin among an increasing user base has opened a new avenue of research in the field of digital forensics involving cryptocurrencies. Since the creation of Bitcoin in 2008, cryptocurrencies have begun to make a presence in the world of e-commerce. Cryptography serves as the underlying foundation for Bitcoin, which gives it the benefits of confidentiality, integrity, non repudiation and authentication. Having been designed and built upon the foundation of these four objectives makes Bitcoin an attractive alternative to mainstream currency and provides users with the benefits of payment freedom, security, very low fees, and fewer risks for merchants.

2.  This presentation brings out the aspects and discusses on BITCOIN FORENSICS.The same was presented at National Information Security Summit (NISS) held at Lucknow,a premier International Information Security Awareness, Cyber Forensics, Malware Analysis, Cyber Cop, Cyber Law & Ethical Hacking Summit with skilled & proficient Speakers from government & private sector.

   Bitcoin is FOREN"SICK" : Threats and Solutions by Anupam Tiwari on Scribd

Few pics of the event below: