Hi Freemoney,
Yes I think that would work.
By marking it as "printed" and then "spent" in your wallet you would not accidentally double spend it.
By having an expiryDate it's state is less ambiguous as time goes on.
It would have to be clear on the note that you have to check the BTC is on the address even if it is before the expiry date.
By their very nature a printed note of a key is a one time use so I imagine they will either have a very short life (print them off just before you need them) or be 'perpetual' in that you are printing them off to save "somewhere safe". In the latter case you would probably want to delete the key out the wallet entirely for more security (once you have checked it has printed ok, obviously).
Topic: MultiBit - page 64. (Read 336309 times)
Hi Jim,
An 'automatic' key management like 'printout of note and immediately remove the key' might be difficult, because in case of printer malfunction one could loose money. But you also want to prevent accidental double spending, and everything should be simple.
Here is my suggestion:
I think printing out a note should be handled similar to spending a cashier cheque:
-After printing, the address should be marked as 'printed' or 'in transfer' or 'cashier cheque obligo'
-This key should not be used for spending anymore.
-When Multibit notices that the address is used on the blockchain, the key should be marked as 'spent'
-If after a defined time the address has not been redeemed on the blockchain (=expiry date of the note), Multibit should transfer the amount from the address automatically to a new address in the same wallet by doing a regular transfer from the address to a new adress on the blockchain.
-This way, it can be ensured that printer malfunctions do not lead to loss of bitcoins or private keys and everything is still simple from a users perspective: No need to recover the key from a backup copy, no need to worry about double spending, etc.
-On the note, an expiry date should be printed, like :"Bitcoins to be redeemed on the blockchain until, otherwise the note becomes invalid".
-The expiry date should be choosable by the user.
In addition to the construction of the notes, it also needs some sort of key management so that you do not use the keys that you have 'printed out' for something else and effectively double spend them. Have not thought that through yet.
An 'automatic' key management like 'printout of note and immediately remove the key' might be difficult, because in case of printer malfunction one could loose money. But you also want to prevent accidental double spending, and everything should be simple.
Here is my suggestion:
I think printing out a note should be handled similar to spending a cashier cheque:
-After printing, the address should be marked as 'printed' or 'in transfer' or 'cashier cheque obligo'
-This key should not be used for spending anymore.
-When Multibit notices that the address is used on the blockchain, the key should be marked as 'spent'
-If after a defined time the address has not been redeemed on the blockchain (=expiry date of the note), Multibit should transfer the amount from the address automatically to a new address in the same wallet by doing a regular transfer from the address to a new adress on the blockchain.
-This way, it can be ensured that printer malfunctions do not lead to loss of bitcoins or private keys and everything is still simple from a users perspective: No need to recover the key from a backup copy, no need to worry about double spending, etc.
-On the note, an expiry date should be printed, like :"Bitcoins to be redeemed on the blockchain until
-The expiry date should be choosable by the user.
I have been following that thread. The artwork is pretty amazing now!
In addition to the construction of the notes, it also needs some sort of key management so that you do not use the keys that you have 'printed out' for something else and effectively double spend them. Have not thought that through yet.
But yes, will put it on the list (which is getting longer everyday!). :-)
edit: https://github.com/jim618/multibit/issues/41
In addition to the construction of the notes, it also needs some sort of key management so that you do not use the keys that you have 'printed out' for something else and effectively double spend them. Have not thought that through yet.
But yes, will put it on the list (which is getting longer everyday!). :-)
edit: https://github.com/jim618/multibit/issues/41
hi Jim,
can you add pls. to your To-Do list some artwork and bitcoin banknote printing function?
https://bitcointalksearch.org/topic/m.1037251
can you add pls. to your To-Do list some artwork and bitcoin banknote printing function?
https://bitcointalksearch.org/topic/m.1037251
I have now got the Send Confirm, Export Private Keys and Import Private Keys hooked up to the encryption. They now:
1) Check if encryption is required.
2) Prompt the user for the password.
3) Checks the wallet password correctly decrypts the wallet.
4) Actually decrypts the wallet
5) Does the Send/ Export/ Import
6) Re-encrypts the wallet afterwards.
Screenshot of the Send Confirm dialog, with some of the checking as "MS Paint" annotations:
1) Check if encryption is required.
2) Prompt the user for the password.
3) Checks the wallet password correctly decrypts the wallet.
4) Actually decrypts the wallet
5) Does the Send/ Export/ Import
6) Re-encrypts the wallet afterwards.
Screenshot of the Send Confirm dialog, with some of the checking as "MS Paint" annotations:
Any news about a function to export transactions in csv?
Hi HostFat,
I have put everything except bug fixes on hold whilst I am working on the encrypted wallets as there are a lot of details to work through.
Jim
Well there is nothing unusual in that log.
It is getting the ticker currencies ok just not the data.
I will put a bit more error logging in the code to try to pin it down in the future.
It is getting the ticker currencies ok just not the data.
I will put a bit more error logging in the code to try to pin it down in the future.
Tim Molter is the developer working on XChange (which I use to get the exchange data). I think he has some early work done on Intersango but it is not yet ready to be used in production yet.
Could you PM me the log just in case there is something in there to indicate what the problem is please ?
Could you PM me the log just in case there is something in there to indicate what the problem is please ?
just did
but my multibit_debug.log says that it was last modified: 20-4-2012.. strange 
Any news about a function to export transactions in csv?
Tim Molter is the developer working on XChange (which I use to get the exchange data). I think he has some early work done on Intersango but it is not yet ready to be used in production yet.
Could you PM me the log just in case there is something in there to indicate what the problem is please ?
Could you PM me the log just in case there is something in there to indicate what the problem is please ?
Hi bitcoinspot.nl,
If you do not see the currency ticker at all, it might be that you have accidentally switched it off. You should be able to do 'View | Show Currency Ticker' to get it back.
If you see the currency ticker but there is no data in it, then it is most likely that MtGox is not serving you up the data. If you look in the log/multibit_debug.log you will see an error like 'TickerTimerTask - HTTP get failed'. There is not that much we can do about that (well, other than writing an interface to another exchange). If there are any other errors in the log then post them here or PM me as it means it is something else that I need to look into.
Jim
If you do not see the currency ticker at all, it might be that you have accidentally switched it off. You should be able to do 'View | Show Currency Ticker' to get it back.
If you see the currency ticker but there is no data in it, then it is most likely that MtGox is not serving you up the data. If you look in the log/multibit_debug.log you will see an error like 'TickerTimerTask - HTTP get failed'. There is not that much we can do about that (well, other than writing an interface to another exchange). If there are any other errors in the log then post them here or PM me as it means it is something else that I need to look into.
Jim
Nopes no error.
Will you be having plans to integrate other exchanges?
Roland.
Hi bitcoinspot.nl,
If you do not see the currency ticker at all, it might be that you have accidentally switched it off. You should be able to do 'View | Show Currency Ticker' to get it back.
If you see the currency ticker but there is no data in it, then it is most likely that MtGox is not serving you up the data. If you look in the log/multibit_debug.log you will see an error like 'TickerTimerTask - HTTP get failed'. There is not that much we can do about that (well, other than writing an interface to another exchange). If there are any other errors in the log then post them here or PM me as it means it is something else that I need to look into.
Jim
If you do not see the currency ticker at all, it might be that you have accidentally switched it off. You should be able to do 'View | Show Currency Ticker' to get it back.
If you see the currency ticker but there is no data in it, then it is most likely that MtGox is not serving you up the data. If you look in the log/multibit_debug.log you will see an error like 'TickerTimerTask - HTTP get failed'. There is not that much we can do about that (well, other than writing an interface to another exchange). If there are any other errors in the log then post them here or PM me as it means it is something else that I need to look into.
Jim
Excuse me for maybe asking a earlier asked question, but the ticker isn't working for me, not before or after the upgrade to the latest version. any tips ?
Roland.
Roland.
Hi Teste,
Yes you can put it in a file and import it.
The easiest way to get the exact format is:
1) Create a new wallet saved to a file, say, teste.wallet
2) Export the private keys, UNENCRYPTED, to a file teste.key.
3) Open up the key file in a text editor. There is a big comment at the top that describes the format. It is simply lines, each line containing the sipa format key - beginning with 5 - and the key creation date in a particular format. You will have an example in there to copy as a new wallet has one key in it.
4) Add in your new key and a date a bit before when you created it.
5) Import the key file back into the wallet.
6) Multibit will then replay the blocks to get the transactions and work out the balance.
Then it is good idea to secure delete the key file so it is not lying around. If you want a quick key backup you can do another key export but add a password so that the key export file is encrypted.
edit: I have added a help 'how-to' note about this here:
http://multibit.org/help_importASingleKey.html
Yes you can put it in a file and import it.
The easiest way to get the exact format is:
1) Create a new wallet saved to a file, say, teste.wallet
2) Export the private keys, UNENCRYPTED, to a file teste.key.
3) Open up the key file in a text editor. There is a big comment at the top that describes the format. It is simply lines, each line containing the sipa format key - beginning with 5 - and the key creation date in a particular format. You will have an example in there to copy as a new wallet has one key in it.
4) Add in your new key and a date a bit before when you created it.
5) Import the key file back into the wallet.
6) Multibit will then replay the blocks to get the transactions and work out the balance.
Then it is good idea to secure delete the key file so it is not lying around. If you want a quick key backup you can do another key export but add a password so that the key export file is encrypted.
edit: I have added a help 'how-to' note about this here:
http://multibit.org/help_importASingleKey.html
Hi,
I generated an address on www.bitaddress.org and copied a private key like this one: (5KkRwQXHo7ke9yYSMH3vfFj7DqE3iwktHtkfb7NEwft2i3wJGCa)
Is it possible import this private key on Multibit? If not, is on TODO list?
I generated an address on www.bitaddress.org and copied a private key like this one: (5KkRwQXHo7ke9yYSMH3vfFj7DqE3iwktHtkfb7NEwft2i3wJGCa)
Is it possible import this private key on Multibit? If not, is on TODO list?
Back to the v0.5 encryption work . . .
When you add new keys/ receiving addresses to an encrypted wallet, you need to supply the wallet password.
This is to encrypt the new keys to match the existing ones.
As this would get tiresome to enter a long password repeatedly, I have put in a dialog where you can choose via a combobox to generate 1, 5, 20 or 100 new keys at a time. It is like populating a keypool. You see it when you click the 'New' on the 'Request Bitcoin' screen.
For unencrypted wallets the wallet password field is disabled but can still choose a number.
edit: finished off dialog.
Screenshot:
When you add new keys/ receiving addresses to an encrypted wallet, you need to supply the wallet password.
This is to encrypt the new keys to match the existing ones.
As this would get tiresome to enter a long password repeatedly, I have put in a dialog where you can choose via a combobox to generate 1, 5, 20 or 100 new keys at a time. It is like populating a keypool. You see it when you click the 'New' on the 'Request Bitcoin' screen.
For unencrypted wallets the wallet password field is disabled but can still choose a number.
edit: finished off dialog.
Screenshot:
There is a new release of MultiBit at:
http://multibit.org
Version 0.4.4
Enhancements:
+ I18n update
+ Update to bitcoinj 0.5.2
Scan of release checklist
This is mainly to update the localisation files and update the bitcoinj version (which has a fix for a sidechain block bug).
http://multibit.org
Version 0.4.4
Enhancements:
+ I18n update
+ Update to bitcoinj 0.5.2
Scan of release checklist
This is mainly to update the localisation files and update the bitcoinj version (which has a fix for a sidechain block bug).
Let me know how you get on as I can write up your experience as a how-to for other people.
Cheers
Cheers
Thank you for the explanation. I will give it a try.
RE: setting a proxy.
With Java generally you can set up a proxy on, say, localhost port 8123, by passing in parameters on the command line.
For Mac and Linux instead of starting MultiBit with:
java -jar multibit-exe.jar
you would start it with:
java -jar -Dhttp.proxyHost=127.0.0.1 -Dhttp.proxyPort=8123 multibit-exe.jar
(I have not tried this as I don't run Tor but a user reported it worked successfully)
A bit of a complication is that the installers on Mac and Linux install the file "multibit-exe.jar" but for Windows I wrap this file into a "multibit.exe" (i.e. a Windows native exe file). Checking the manual of the product I use to make it (JSmooth) it does not look like you can pass in parameters on the command line. You can actually use the multibit-exe.jar from any of the other installers - it works on all 3 platforms.
It would certainly be easier for it to be settings in the Preferences panel that is for sure so I will put it on the TODO list.
edit: https://github.com/jim618/multibit/issues/35
With Java generally you can set up a proxy on, say, localhost port 8123, by passing in parameters on the command line.
For Mac and Linux instead of starting MultiBit with:
java -jar multibit-exe.jar
you would start it with:
java -jar -Dhttp.proxyHost=127.0.0.1 -Dhttp.proxyPort=8123 multibit-exe.jar
(I have not tried this as I don't run Tor but a user reported it worked successfully)
A bit of a complication is that the installers on Mac and Linux install the file "multibit-exe.jar" but for Windows I wrap this file into a "multibit.exe" (i.e. a Windows native exe file). Checking the manual of the product I use to make it (JSmooth) it does not look like you can pass in parameters on the command line. You can actually use the multibit-exe.jar from any of the other installers - it works on all 3 platforms.
It would certainly be easier for it to be settings in the Preferences panel that is for sure so I will put it on the TODO list.
edit: https://github.com/jim618/multibit/issues/35
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