holiman

contract DropBox{
	
	/*
	Central Bank of Ethereum

	A very minimalistic bank/dropbox where Ether can be sent. 
	This makes it simple for a service to pay recipients without directly
	invoking any unknown (potentially hostile) contracts. 
	Instead, the value transfer becomes a 2-step handover, where the service
	deposits to the bank, and the recipient cashes out later. 

holiman

Keybase proof

I hereby claim:

• I am holiman on github.
• I am holiman (https://keybase.io/holiman) on keybase.
• I have a public key whose fingerprint is CA99 ABB5 B36E 24AD 5DA0 FD40 683B 438C 05A5 DDF0

To claim this, I am signing this object:

holiman

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holiman

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holiman

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holiman

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holiman

The values above, but translated into a table

Name                                         Gascost         Time (ns)       MGas/S    Gasprice for 10MGas/S  Gas/Ideal percent
-----------------------------------------  ---------  ----------------  -----------  -----------------------  -------------------
PrecompiledEcrecover/                           3000  171600              17.4825                   1716      174.8 %
PrecompiledSha256/128                            108     675             160                           6.75   1600.0 %
PrecompiledRipeMD/128                           1080    2336             462.329                      23.36   4623.3 %
PrecompiledIdentity/128                           27      18.8          1436.17                        0.188  14361.7 %
PrecompiledModExp/eip_example1                  2611  140894              18.5317                   1408.94   185.3 %

holiman

PREIMAGES map[]
{
    "root": "d7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544",
    "accounts": {
        "000d836201318ec6899a67540690382780743280": {
            "balance": "200000000000000000000",
            "nonce": 0,
            "root": "56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
            "codeHash": "c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470",
            "code": "",

holiman

Signatures included

Not listing calls made fewer than 5 times

1177020 0xa9059cbb-64 47.53% (47.53% aggregate)
107508 0xef343588-576 4.34% (51.88% aggregate)
66946 0x23b872dd-96 2.70% (54.58% aggregate)
46585 0x095ea7b3-64 1.88% (56.46% aggregate)
39975 0x70a08231-32 1.61% (58.07% aggregate)
34695 0x2295115b-256 1.40% (59.48% aggregate)

holiman

Stopping spam

This blog post by Jonathan Brown suggested replacing SMTP with Ethereum blockchain; specifically, utilizing the log channel to monitor events.

With this approach, emails wouldn't actually be stored within the EVM (Ethereum Virtual Machine) storage, but every email would still be present in the blockchain blocks. The EVM log mechanism would make it simple for a full node to monitor and be alerted whenever an email was submitted.

I don't believe that this would be feasible in the real world, for several reasons

• There are lots of email being sent, some of them quite large
• Most people wouldn't want their emails forever on the blockchain, the future resiliency of GPG is unknown, and GPG encryption does not provide perfect forward secrecy. Once a key is compromised, all is revealed.