1. Nathan Krussel

2.  What is a Crypto Currency  Purpose of Crypto Currency  What is Bitcoin  How does Bitcoin work  Mining BTC  How people perceive Bitcoin  Current Uses for BTC  Future of BTC

3.  A digital medium used in exchanges.  Cryptographically secure  Distributed  Peer-to-Peer  Decentralized  Mutual distrust  “Anonymous”

4.  Remaining Anonymous  Deregulation of Currency  Secure Money Transactions  Public Ledger of Currency and Exchanges  Speedy Transactions  World Wide Use  No exchanges to worry about  No freezing of ones account  Reliable and Immutable

5.  Also known at BTC  Much like the U.S. Dollar is known as USD  The most commonly known Crypto Currency, and the pioneer that brought it to farm  Not the first electronic cryptographic currency  Most successful Crypto Currency to date  When most people think of a Crypto Currency they think of Bitcoin  Completely Digital Currency, nothing is on paper and isn’t backed by anything else other than its self.  http://www.youtube.com/watch?v=Um63OQz3bjo http://www.youtube.com/watch?v=Um63OQz3bjo

6.  Created in 2009 by Satoshi Nakamoto  Uses double SHA-256  SHA-256 of a SHA-256  Governed by the Block-Chain  This is distributed amongst the nodes, so no one person can modify it  Has the record of every transaction ever made  Roughly 13.5 GB as of 1/22/2014  281988 blocks have been created  Can be broken up into 8 decimal places. USD is 2 decimal places.  This can be expanded in the future if the value of BTC increases dramatically

7.  Based off a public ledger known as the block- chain  Everything about the transactions (from, to, how much, when) is all public knowledge  This creates an open nature.  Aims to create a new block every 10 minutes  Does this by adjusting the difficulty  Difficulty changes ever 2016 blocks  To “solve a block” one must compute the correct hash  There is a target number, that the hashed value must be equal to or lesser than.

8.  Not a linear chain, but one that has forks and self heals.  Forks occur when two blocks are presented as solved within a few seconds of each other.  The “correct” chain is the one with the longest path back to the genesis block.  The fork that is the incorrect, now all those blocks in that fork become invalidated.  The faster the hashing rate of the network as a whole, the more secure the block chain is  The chain will guarantee a block is validated after 100 blocks are attached onto the end of the chain.

10.  Difficulty changes every 2016 blocks to ensure it takes about 10 minutes a block.  Dynamically adjusted by the entire network.  Difficulty is calculated as follows  Difficulty = Difficulty_1_target/current target  Target is what the sha256 block header must be equal to or less than  The lower the target, the more difficult this is to solve.  August 5 th 2013 Difficulty: 31,256,960.73  Jan 23 rd 2014 Difficulty: 1,789,546,951

11.  To solve a block the SHA-256 of the block header must be equal to or less than the target  Every bitcoin client compares the actual time it took to solve the 2016 blocks to the two week goal.  The modifies the target by the percentage difference.  A single retarget never chances the target by more than a factor of 4, so there aren’t large spikes in difficulty.

12.  CPU  Was the original way to do it, was initially solo mining (not pooled) and you got all of the block or none of it (50 BTC)  Slow compared to today’s standards.  Core i5 2500 about 20.6 megahash/s

13.  GPGPU  Somebody wrote a program that would use the GPU’s within PC’s to mine, this was discovered to be more energy efficient per hash, and gave you an advantage in higher hash rates.  AMD/ATI GPU’s were much faster and more efficient per megahash using OpenCL  AMD 6870 (3 year old card as of now purchase price about 150 USD) ~300 megahash/s

14.  Specialty hardware/ASIC  These have been recently released, and are designed specifically just to mine for BTC  Much more expensive then GPU’s, but exponentially faster.  Bitforce 60 about 2500 purchase price, 60 gigahash/s  Newer models will cost 12,000 but produce 3 terahash/s or faster.

15.  Many people see it as a way to do nefarious activity and that’s all the use they can see for it.  Others see it as a way to “stick it to the man”  Some who are just mining see it as a way to cash out and make some money  Certain Individuals see this as just a different currency that you are in complete control of.

16.  Some retailers take BTC  Overstock is the newest one, newegg has hinted at it.  Sacramento Kings now accept BTC  A few smaller online retailers take BTC  Many miner producing companies accept BTC  Use an exchange to trade BTC out for your currency of choice.  Bitcoin is still in its infancy of adoption, so the list of people who accept it grows everday

17.  More retailers will begin to accept BTC  Used in international trading to avoid currency exchanges  Become as common place as credit cards  Less volatility in hard currency value (USD)  Nefarious uses  Currency Flops and becomes worthless

18.  http://en.wikipedia.org/wiki/Crypto-currency http://en.wikipedia.org/wiki/Crypto-currency  http://bitcoin.org/bitcoin.pdf http://bitcoin.org/bitcoin.pdf  https://en.bitcoin.it/wiki/Block_chain https://en.bitcoin.it/wiki/Block_chain  https://blockchain.info/  https://en.bitcoin.it/wiki/Difficulty https://en.bitcoin.it/wiki/Difficulty  https://en.bitcoin.it/wiki/Target https://en.bitcoin.it/wiki/Target  http://www.youtube.com/watch?v=Um63OQ z3bjo http://www.youtube.com/watch?v=Um63OQ z3bjo  https://en.bitcoin.it/wiki/Mining_hardware_c omparison https://en.bitcoin.it/wiki/Mining_hardware_c omparison