Blockstack, a New Internet for Decentralized Apps. Muneeb Ali

Transcription

1 Blockstack, a New Internet for Decentralized Apps Muneeb Ali

2 The New Internet

3 Problems with the traditional internet

4 End-to-end design principle for the Internet. *1981 Saltzer, Reed, and Clark paper

5 End-to-end Design

6 DNS PKI Authentication User Data

7 Problem: Trusting DNS DNS

8 In 2010, an ISP in Chile started using DNS info from Chinese (Netnod) servers.

9 Problem: Trusting PKI CAs

10 Problem: Trusting PKI

11 End-to-end design principle for the Internet.

12 Trust-to-trust End-to-end design principle for the Internet. * Clark and Blumenthal

13 Trust-to-Trust Design

14 Problem #1: DNS & PKI are not in user trust zones

15 Problem: Trusting cloud services

16 Problems with the traditional internet Problem #1: DNS & PKI are not in user trust zones Problem #2: User data and apps are not in user trust zones #1: Decentralized DNS & PKI #2: Decentralized storage & discovery

17 Background on Blockchains

18 How Blockchains Work Blockchain It s a file! Append-only global log Every node on the network has a consistent copy

19 How Blockchains Work Private-public key pairs Bitcoin address deterministic from public key Example: Priv: 4c542a0725fa39ce6a120b76a5c9f2c7627ba8b92b61e43f3e9da581ebe27636 Pub: 040a62c fec301ef0cf8c16a b4a2f686a53bfa49473ab25abdaa48da0f36b8474d5a 2aceb6b7cc39c405e cacf25ab92 Bitcoin address: 1CnrAAXA743VnVbW5LZtFrZiaZpXHUYKzg

20 Bitcoin s P2P Network Blockchain

21 How Blockchains Work Prev. block-hash Meta-data Transactions SHA256 + Block n Block n+1 Block n+2 Nonce (in-progress) (solution) Resulting hash Nonce

22 Limitations of Blockchains 1) Limited data storage & bandwidth 2) Hard to introduce new features 3) Slow writes 4) The endless ledger problem

23 Blockchain DNS + PKI

24 Zooko s Triangle Decentralized Secure (ownership) Human-meaningful Long hash is secure & decentralized e.g., 1Hdsfd34fDdgeTe Twitter handle is human-meaningful & secure Blockchains can give all three! (e.g., Namecoin)

25 Naming System on a Blockchain: Register hash(name) Update name

26 Blockchain DNS & PKI Namecoin, 2011 Blockchain Name System (BNS), 2014 Ethereum Name Service (ENS), 2017

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30 Lessons from a production deployment

31 Production system on Namecoin: Used u/ namespace Live between March 2014 and August ,000 registrations Over 200,000 transactions

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33 Namecoin Experience Discovered and reported the Namecoin 51% attack vector. First analysis of Namecoin's network reliability (production data). First report on selfish mining. See USENIX ATC 16 paper for details

34 Blockstack Architecture

35 Security Box Follow David Clark s trust-to-trust principle

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39 Example Zone File:

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42 Secure Internet Can ask for consensus hash from friends

43 Virtualchains

44 Virtualchains Blockchain Virtualchain op_code, hash name_op, hash op_code, hash name_op, hash op_code, hash name_op, hash op_code, hash name_op, hash name_op, op_code, hash n Blockchain b n-3 b n-2 b n-1 b n

45 Virtualchains: Migration Blockchain A Blockchain B

46 Blockchain Name System (BNS)

47 DNS vs. BNS DNS Root Servers 6 3 TLD Servers.com TLD Servers.edu Authorative Server DNS Core Infrastructure Local DNS Server (cache) 8 1 End-user

48 DNS vs. BNS DNS Root Servers 6 3 TLD Servers.com TLD Servers.edu 7 2 Root Blockchain 5 4 Authorative Server DNS Core Infrastructure Local DNS Server (cache) 8 1 sync TLD Blockchain.id TLD Blockchain.app BNS Decentralized Infrastructure End-user sync 1 Trust Zone 4 Local BNS Server (cache) 2 Peer Network 3

49 Scalability: Multiple-blockchains Global Naming (TLDs) Blockchain Driver Blockchain Driver Blockchain Driver Bitcoin Ethereum Hyperledger

50 Scalability: Subdomains Cryptographic commit of subdomains Use instead of muneeb.id

51 Peer Networks & Storage

52 Peer Network: Atlas Unstructured Full replication Targets a subset of the problem space

53 Decentralized Storage Block N-5 Dropbox Block N-4 Amazon S3 Google Drive FreeNAS Server (name, hash) Block N-3 (encrypted data) Peer Network lookup(hash) Block N-2 lookup(uri) Block N-1 Peer Node (full index) Block N Storage Layer Discovery Layer Virtualchain Layer

54 Solutions for Blockchain Limitations 0) Security issues > Need most secure blockchain (migrate) 1) Storage limitations (blockchain bloat) > Unlimited data 2) Introducing new features (hard fork) > Virtualchain 3) Slow writes > Get operations off blockchain path 4) Endless ledger problem > Fast bootstrapping

55 Applications and Current Impact

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60 Registrations in the.id namespace 60,000 58,000 56,000 54,000 52,000 50,000 48,000 46,000 44,000 42,000 60, ,000 38,000 36,000 34,000 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept

61 Blockstack Usage

62 Storage Performance - Mostly network bound (~5% overhead in filesize) - 2 secs CPU for 100MB file - Can give comparable performance to cloud storage

63 Organizations building on Blockstack range from startups to academic institutions to large enterprises Rushwallet Tor (pipeline)

64 Decentralized Apps & App Fund $25 million fund to build decentralized apps

65 There are developer meetups around the world

66 plus open-source contributors and community members

67 Blockstack Token

68 More Info: Website: blockstack.org Code: github.com/blockstack Thank you