Introducción de Alberto Gómez al protocolo de Bitcoin y al lenguaje Bitcoin Scripting, el cual permite desarrollar características y comportamiento sobre el dinero y las transferencias de valor.

1. Leganés
6 Febrero 2013
Alberto Gómez Toribio ( @gotoalberto )
Bitcoin protocol for developers
Except where otherwise noted, this work is licensed under: http://creativecommons.org/licenses/by-nc-sa/3.0/
c_b_n_a

2. Coinffeine.com
Leganés
6 Febrero 2013
Alberto Gómez
@gotoalberto
“OpenData and Bitcoin Developer on fire.
Great coders are today’s rock stars. That’s it!”
Alvaro Polo
@apolovald
“Software development enthusiast and aviation geek. Give me a
higher-order function and I shall move the world.”
A P2P Bitcoin exchange
Sebastián Ortega @_sortega
“Vocational coder since childhood, he will annoy you with concepts
like "monad" and "actor model" but gets the work done.”
Ximo Guanter
“Theoretical computer science believer by night, pragmatic ship-it developer by day.
My brain runs on glucose, caffeine, general abstract nonsense and type theory.”
Except where otherwise noted, this work is licensed under: http://creativecommons.org/licenses/by-nc-sa/3.0/
c_b_n_a

3. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
What is the Bitcoin Protocol?
● Network protocol
○ Blockchain mining
○ Fees and commitment rules
○ Sharing protocol: Gossip, Bittorrent, Gnutella...
● Transactions Mechanics
○ Validations of the money source
○ Protocol to spend the money
○ Bitcoin Scripting

4. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Network protocol
● Blockchain
○ The Blockchain is a distributed ledger book
○ Create a Block in chain require a proof of work
dc7047be… = SHA256(new_block_hash)
○ Forks are discarded, the most complex chain wins.

5. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Network protocol
● Other services:
○ The Blockchain is used to storage
usernames.
○ Tweets are shared between users using a DHT protocol.
○ The older messages are discarded.
○ Incentive to generate blocks on Blockchain:
Sponsored messages.

6. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Network protocol
● Colored Coins:
○ The Blockchain is used to storage key-value strings,
as internet web domains / IP.
○ You can register a domain spending Namecoins.
○ The fee by register a name is decreased in time.

7. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

8. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
Transaction Id, changes when a field is changed or tx is signed.
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

9. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
Locktime, Block or Time up to which this tx cannot be broadcasted.
vin
: [
{
txid
: feff4b…
vout
: 0
scriptSig
{
asm : d8f67a…
…}
…}
…]
vout
: [
{
value
: 2.52
reqsigs
: 1
scriptPubKey {
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
…}
addresses
: [ 172D5w7C… ]
…}
…]
…}

10. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
TXid reference output for this input.
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

11. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
Output number reference in previous tx
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

12. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
ScriptSig which unlock the
connected OutputScript
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

13. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
Value to transfer. The difference with the
summatory of inputs values is the fee.
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

14. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
addresses
…}
…]
…}
:
:
{
…}
:
Number of sigs required to broadcast this
transaction. The signers are included in the
“addresses” array.
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
2.52
1
[ 172D5w7C… ]

15. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
…}
…]
…}
Script. It defines how the money can be spent and by whom.
value
: 2.52
reqsigs
: 1
scriptPubKey {
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
…}
addresses
: [ 172D5w7C… ]

16. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Transactions Mechanic
● Transaction anatomy
{
txid
: 5c084b… ,
locktime : 0,
vin
: [
{
txid
vout
scriptSig
:
:
{
feff4b…
0
asm : d8f67a…
…}
…}
vout
…]
: [
{
value
reqsigs
scriptPubKey
:
:
{
2.52
1
asm : OP_DUP OP_HASH160 cb1f48…
OP_EQUALSVERIFY OP_CHECKSIG
addresses
…}
…]
…}
…}
:
[ 172D5w7C… ]

17. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Bitcoin Script
● It Allows to define how an output will be spent
and by whom.
● Is a non Turing-Complete language which is
evaluated as a Stack, from left to right.
● It just allows to write pure functions
(without context)
● Is a non Turing-Complete language which is
evaluated with a stack machine.

18. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
OP_EQUALVERIFY OP_CHECKSIG

19. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Signature)
(Public Key)
bbba3f5… 172D5w7C…
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
OP_EQUALVERIFY OP_CHECKSIG

20. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Signature)
(Public Key)
bbba3f5… 172D5w7C…
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
Stack
OP_EQUALVERIFY OP_CHECKSIG

21. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Signature)
(Public Key)
bbba3f5… 172D5w7C…
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
Stack
OP_EQUALVERIFY OP_CHECKSIG

22. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key)
(Public Key Hash)
172D5w7C…
OP_DUP OP_HASH160 cb1f48…
Stack
(Signature)
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

23. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key)
(Public Key Hash)
172D5w7C…
OP_DUP OP_HASH160 cb1f48…
Stack
(Signature)
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

24. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
Stack
(Public Key)
(Signature)
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

25. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
OP_DUP OP_HASH160 cb1f48…
Stack
(Public Key)
(Signature)
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

26. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
OP_HASH160 cb1f48…
Stack
(Public Key)
(Public Key)
(Signature)
172D5w7C…
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

27. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
OP_HASH160 cb1f48…
Stack
(Public Key)
(Public Key)
(Signature)
172D5w7C…
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

28. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
cb1f48…
Stack
(Public Key Hash)
(Public Key)
(Signature)
cb1f48…
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

29. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
(Public Key Hash)
cb1f48…
Stack
(Public Key Hash)
(Public Key)
(Signature)
cb1f48…
172D5w7C…
bbba3f5…
OP_EQUALVERIFY OP_CHECKSIG

30. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
OP_EQUALVERIFY OP_CHECKSIG
Stack
(Public Key Hash)
(Public Key Hash)
(Public Key)
(Signature)
cb1f48…
cb1f48…
172D5w7C…
bbba3f5…

31. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
OP_EQUALVERIFY OP_CHECKSIG
Stack
(Public Key Hash)
(Public Key Hash)
(Public Key)
(Signature)
cb1f48…
cb1f48…
172D5w7C…
bbba3f5…

32. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
OP_CHECKSIG
Stack
(Public Key)
(Signature)
172D5w7C…
bbba3f5…

33. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
How Bitcoin Script works?
OP_CHECKSIG
Stack
(Public Key)
(Signature)
172D5w7C…
bbba3f5…

34. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
How Bitcoin Script works?
(EMPTY)
Stack
(EMPTY)
SUCCESS!
#BitcoinT3F

35. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<Sig> <PubKeyB> <7bb> <5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF

36. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<Sig> <PubKeyB> <7bb> <5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Random
diversion!
@_sortega

37. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<Sig> <PubKeyB> <7bb> <5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack

38. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<PubKeyB> <7bb> <5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<Sig>

39. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<7bb> <5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<PubKey>
<Sig>

40. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<5aa> OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<7bb>
<PubKey>
<Sig>

41. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_2DUP OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<5aa>
<7bb>
<PubKeyB>
<Sig>

42. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_HASH160 <aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<5aa>
<7bb>
<5aa>
<7bb>
<PubKeyB>
<Sig>

43. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<aHash> OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<aHash>
<7bb>
<5aa>
<7bb>
<PubKeyB>
<Sig>

44. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_EQUALVERIFY OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<aHash>
<aHash>
<5aa>
<7bb>
<7bb>
<PubKeyB>
<Sig>

45. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_SWAP
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<5aa>
<7bb>
<7bb>
<PubKeyB>
<Sig>

46. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_HASH160 <bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<7bb>
<5aa>
<7bb>
<PubKeyB>
<Sig>

47. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<bHash> OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<bHash>
<5aa>
<7bb>
<PubKeyB>
<Sig>

48. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_EQUALVERIFY <1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<bHash>
<bHash>
<5aa>
<7bb>
<PubKeyB>
<Sig>

49. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<1> OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<5aa>
<7bb>
<PubKeyB>
<Sig>

50. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_LEFT OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<1>
<5aa>
<7bb>
<PubKeyB>
<Sig>

51. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_SWAP <1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<5>
<7bb>
<PubKeyB>
<Sig>

52. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<1> OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<7bb>
<5>
<PubKeyB>
<Sig>

53. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_LEFT OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<1>
<7bb>
<5>
<PubKeyB>
<Sig>

54. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
OP_ADD <2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<7>
<5>
<PubKeyB>
<Sig>

55. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
The sky is the limit! (Odd/Even Bet)
<2>
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<12>
<PubKeyB>
<Sig>

56. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
The sky is the limit! (Odd/Even Bet)
OP_SWAP OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<2>
<12>
<PubKeyB>
<Sig>
#BitcoinT3F

57. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
The sky is the limit! (Odd/Even Bet)
OP_MOD
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<12>
<2>
<PubKeyB>
<Sig>
#BitcoinT3F

58. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
The sky is the limit! (Odd/Even Bet)
OP_IF
OP_DUP OP_HASH160 <pubKeyAHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ELSE
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
OP_ENDIF
Stack
<0>
<PubKeyB>
<Sig>
#BitcoinT3F

59. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
The sky is the limit! (Odd/Even Bet)
OP_DUP OP_HASH160 <pubKeyBHash> OP_EQUALVERIFY OP_CHECKSIG
Stack
<PubKeyB>
<Sig>
(Standard Script)
#BitcoinT3F

60. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
The sky is the limit! (Odd/Even Bet)
● Possible real use:
○ Random user to pay the transaction fees.
○ Help to define asymmetric scenario (secrets)
#BitcoinT3F

61. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Context: Oracles
● The oracle contract allow define how the money
is spent including external state.
○ Allows to make reversible transactions.
○ Allow to pay, only if an external condition is true, for
example the result of a search in google, or the API SEUR
response.

62. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Context: Oracles
● Example of a reversible payment using a Oracle
○ First you generate (in private) a multisig transaction as
this:
TX1
in { 1 BTC BOB }
out { 1 BTC MULTISIGVERIFY BOB SAM }
○ Then you must obtain signed from counterpart:
TX2
in { TX1[0] }
out { 1 BTC
TX3
in { TX1[0] }
out { 1 BTC
<SeurAPI(trackID) == ‘RETURNED’>
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY }
<SeurAPI(trackID) == ‘DELIVERED’>
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <BobPubKey> 2 OP_CHECKMULTISIGVERIFY }

63. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
TX2
in { TX1[0] }
out { 1 BTC
<SeurAPI(trackID) == ‘RETURNED’>
OP_HASH160 <ExternalScriptHash>
OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2
OP_CHECKMULTISIGVERIFY }
#BitcoinT3F

64. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Context: Oracles
● Execution
<OracleSig> <SamSig> <SeurAPI(trackID) == ‘RETURNED’>
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack

65. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Context: Oracles
● Execution
<SamSig> <SeurAPI(trackID) == ‘RETURNED’>
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<OracleSig>

66. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Context: Oracles
● Execution
<SeurAPI(trackID) == ‘RETURNED’>
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<SamSig>
<OracleSig>

67. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
OP_HASH160 <ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<SeurAPI(trackID) == ‘RETURNED’>
<SamSig>
<OracleSig>
#BitcoinT3F

68. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
<ExternalScriptHash> OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<ScriptHash>
<SamSig>
<OacleSig>
#BitcoinT3F

69. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
OP_EQUALSVERIFY
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<ExternalScriptHash>
<ScriptHash>
<SamSig>
<OracleSig>
#BitcoinT3F

70. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
<OraclePubKey> <SamPubKey> 2 OP_CHECKMULTISIGVERIFY
Stack
<SamSig>
<OracleSig>
#BitcoinT3F

71. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Context: Oracles
● Execution
SUCCESS!
Stack
#BitcoinT3F

72. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Fees? Micro Payment Channels!
● Transactions from a checkpoint without
broadcast
● Allows commit money safely
● Allows to pay on demand by the second
● For example: decentralized WiFi Hotspots or
subcontracting services in third world countries.

73. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
#BitcoinT3F

74. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
#BitcoinT3F

75. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
#BitcoinT3F

76. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
#BitcoinT3F

77. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
IN {TX1[0] 1 BTC
}
OUT {0: 0,9 BTC BOB
0,1 BTC SAM }

78. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
IN {TX1[0] 1 BTC
}
OUT {0: 0,8 BTC BOB
0,2 BTC SAM }

79. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
IN {TX1[0] 1 BTC
}
OUT {0: 0,7 BTC BOB
0,3 BTC SAM }

80. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
IN {TX1[0] 1 BTC
}
OUT {0: 0,6 BTC BOB
0,4 BTC SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
BREAK!

81. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
Micro Payment Channels Mechanic
TX1
IN {0: 1 BTC
}
OUT {0: 1 BTC MULTISIG BOB SAM }
TX2
IN {TX1[0]: 1 BTC
}
OUT {
0 : 1 BTC BOB }
LOCKTIME : 18
IN {TX1[0] 1 BTC
}
OUT {0: 0,6 BTC BOB
0,4 BTC SAM }

82. Leganés
6 Febrero 2013
Bitcoin Protocol for Developers
#BitcoinT3F
THANKS!
● BigData is the current wave, P2P is the next.
● APIs and P2P are the next challenge on finantial world.
● Bitcoin technology and protocol is here to stay.