Topic: Searching alternative client... (Read 6506 times)

I think when their is already a coin age and the transaction is bound to a block, the coin age cant be faked. Which means btc couldnt expire before 99 years. So it would be safe to assume that btc that lie 99 years at one address are abandoned. I dont see a reason why there still should be an owner after that time.
So this way the available amount of bitcoins remains stable plus, when all 21.000.000 btc are mined the network could held stable by let these btc mine again.
So i dont see much of a risk at this. I think the more that it could help stabilize the network because miners could find a lost treasure this way, keeping the network running after all is mined.
Because i fear, when all is mined the network will be in trouble until fees for transactions are high enough that miners work again. This could only help a bit of course.

Anyway... youre right... in 99 years bitcoin probably is gone. Or its a sunsystem currency...

Sounds like a horrible idea. If you have any other form of currency, it doesn't disappear if you don't spend it, regardless of how long it's been sitting in a drawer or under a mattress.

In 99 years though we'll have moved on to something else anyway. I don't see a point to having a possible time-out attack vector added.

So there already exists a coin age? In this thread here: https://bitcointalksearch.org/topic/can-bitcoin-die-at-some-date-because-of-stranded-bitcoins-112525 the idea came up to let btc die after 99 years when they werent moved for that time. This could prevent that btc are lost in the network for whole future only because persons died or the access to these addresses is gone through another way.
So is this coin age attached to the transaction with btc and address? If so do you see the possibility that this age can be taken to let btc vanish when coins are lying at one address for 99 years so that miners can mine them again? Or would that include a securityrisk because the timeout could be manipulated?

Regarding the fee... beneath the voluntary fee there is a enforced fee. When i understand you right you are saying that miners wont take a transaction into the next block when the btc are sent already too short before? Only when they get a fee.
But you wrote too that the fee is enforced when the transaction is too big in data. So when is one transaction big? It can only be big when the btc has a big history of transactions isnt it? Because sending many satoshis from one address to many others or receiveing many satoshis at one address from many others would be all different transactions.

So when you have 1btc that went through 1000 transactions before then another transaction would have a huge size which means a fee is enforced.
But that would mean that this btc has in fact a lower value. Because when i had the choice to chose such a btc or a freshly mined btc i would use the fresh one because he wont cost me fee because of transaction size. Isnt that a problem? I mean when someone has to get 1000btc because he sold something to another person and he gets btc that have big transaction history then he got less value.
Am i wrong?

I didn't assume I send to only 1 address. And your right the network won't know that all the transactions come from the same guy if he uses different addresses. But that doesn't matter since you have to pay a fee to send a single satoshi you just got not only if you send a few million.
That's why there exists a coin age which is very important for the fee.

But you assume that you send from and to only one address. But what when you send to different addresses. The network wouldnt know that they are in the same wallet. And when each millions part is on million addresses they could be sent to another millione adresses. And so on. Of course that means creating addresses all the time and you would need more btc because of the waitingtime until first confirmation.
Im not sure but when its all different addresses?

It's important here to notice how transactions actually work. You can split a single bitcoin in 100millionen parts. But that transaction has atleast 1 input (1btc) and 100millionen outputs (for every satoshi one output). That transaction would be gigantic in kilobytes because of the amount of outputs and therefore a huge fee would be needed to send that transaction. An average transaction has something like 2 inputs and 2 outputs.
If you want to send those 100 millionen satoshis right again you can't without a fee because they are all very new.

The attack is blocked by that. If you don't think so take 0.1BTC and send 10 times 0.01BTC without a fee to a new address. If it works which i doubt (atleast without waiting for a long time) then send all the 0.01BTC back again without using a fee.

Read that page to understand what i mean with inputs/outputs
https://en.bitcoin.it/wiki/Transaction

wabber... but such an attacker could split 1btc into 1million parts and send it back and forth to new addresses. When the protocol doesnt use the ip and the addresses are new one always then i think it will be hard to find out that its an attack isnt it? Or will every millions part of the 1btc have a history that lets the network know what its used for? If so then this money would be worth less because the transactions it went through makes it a big transaction isnt it? So that miners want a fee. Is that so or does the network only see that this one address received money the first time?

When i think about it cant be this way because at some point all bitcoins has to be moved many many times and the transaction log would be huge for every btc.

So i think an attack couldnt be blocked easily.

that's what I meant. I consider a 0 confirmation transaction "not spent" and as you said a transaction can't get a confirmation before all its inputs have atleast 1 confirmation. And ofc you can send a transaction based on a 0 confirmation input I think that's what satoshi dice does to prevent double spendings.

There's no such restriction, you can also spend coins with no confirmation, but they will not be included in the block right away.

hm well actually the bitcoin protocol enforces only 1 confirmation before a coin can be spent. But to spend your coins you need a miner to include it in a block. But it's considered standard within miners to include transactions with a sufficient fee for the size and coin age first.
Bitcoin clients usually force you to use a appropriate fee so your transactions won't end up unconfirmed. Normally electrum should let you ignore the fee, atleast for me it does so I don't really know why it didn't work with that particular server.

About transaction spammer attacks:
Ofc they can change the source code they could even use their own client but they still need a miner to include their transaction. Creating fresh addresses won't help anything. If i had 1BTC to spam the network and send it to myself then i have to wait for some confirmations before i can spend it for free again and how am I supposed to spam the network if I have to wait for a pretty long time before i can spend my bitcoin for free again.

The coins had 6 confirmations already. So i think its the server itself that wanted a fee. Because instantly after i changed the server no errormessage appeared anymore. Possible?

When this would be a security against some kind of ddos then it doesnt look like a far advanced one. I mean someone who wants to do this surely can change a line of code in an open source wallet to prevent the fee if its included in the client. Or if its the network itself then simply create a script that creates new addresses on the fly and sending back and forth the money to a new address everytime. Would take more processortime but would solve the feeproblem. But maybe this was taken in advance already.

the age of coins depends on when they were last used in a transaction. Example: FriendA sent you 2 BTC yesterday he mined on the same day. FriendB sends you 2BTC today he got from someone who got them from someone etc. Then the coins from friendB are newer because you got them today so the last time they were used in a transaction was today even though they existed for a longer time already. It has nothing to do with the address.
The idea behind that is if you have 2 ppl who want to spam the bitcoin network with transaction can't send the same coins to each other all the time. They would have to wait or pay a high transaction fee.

On the number of servers its usually around 4-7 servers my own (176.9.206.164) was just down for maintenance and not all servers are public you can only see the public ones in your list ofc.

About the coins in your electrum wallet. I suppose you just created that wallet and sent some bitcoins to it. Because they were just used in a transaction means they are very young and that's why the server said they probably wont go through if you sent them without a transaction fee.

Hm... i have 10.66415915 btc in my wallet now. Its a fresh address. I wanted to send it without a fee and now got 2 times a message "error: Transaction rejected by bitcoin network".

I then chose electrum.novit.ro server and it went through without problems. Looks like the other server, electrum.bytesized-hosting.com had a minimum fee? But good that this can be circumvented by chosing another server.

By the way... i only have 3 servers in my list. I remember that yesterday there were 6 or 7. And i guess there are way more than that. Why are there only 3 servers in the list?

What about offline tx signing like what electrum offers? I think that's one of the more important security features a client can offer. Any plans for it?

Hm... do i understand this right that there are bitcoins that are of a lower quality because they have gone through too many transactions? Or does this only depend on the address used?

I mean when this is correct then getting freshly mined coins would be better than really old coins because the old coins would be harder to transfer. And because of that people would choose fresh ones above old ones. So in fact a bitcoin could have another value than a bitcoin because its older.

When this is only about addresses then thats no problem am i right? You only would need to use a fresh address and everything is fine.

That's what i meant in electrum the fee is purely optional it only suggest a fee to pay. There are no forced fees in electrum.

Fee is based on the transaction priority which is based on the age of the coins (to prevent transaction spamming) and the size of the transaction. And size of the transaction doesn't mean the amount of btcs sent it's the size of the transaction in kilobytes which depends on the number of inputs/outputs.

And yes most of the time the transaction fees aren't necessary because there are ppl processing your transaction anyways. But if you use coins you have just received in a large(bytes) transaction your tx can take days to process. Just check out the threads on this forum it happened to some ppl (especially those who play satoshi dice, because they use the coins they just got again).

I knew before that there is a fee you can choose to pay. But the original client does have a forced fee too. I think its triggered when sending too often. Or maybe when youre amount is too small because i wanted to test multibit encrypted wallet by sending 0.0001BTC. The original client wanted to force me to pay 0.0005BTC Fee. Thats 500% of the original value. I raised the BTC to transfer and up to 0.1BTC i had to pay. At 1BTC it didnt force me. Before i only had the chance to pay the fee or abort the transfer.

Is this built into electrum too?

Regarding the fee... i know about the reason for this but i think its a myth that a transaction can take days with out a fee. I made some transactions till now and a fee makes no difference in any way. And transactions with no fee doesnt take longer. I think maybe a fee is needed once mining doesnt work anymore. But at the moment i think it doesnt make sense.

I think i will try electrum a bit more and probably have to pay the fee in multibit to get my btc out.

electrum shows all digits for me. And about the transaction fee you asked about earlier, electrum suggest a fee but you are free to change it as you like before you send the transaction. But you should also keep in mind that if you lower the transaction fee it could take days until your transaction is processed by the bitcoin network and 0.001BTC or something is almost nothing and it's not wasted. It goes directly to the miners.

And as flatfly said the server could only lie to you about your balance or it could refuse to send transactions. But since the server is opensource just like the client there are multiple servers. So if you think the server is lying to you about your balance just ask another too. It's just two clicks to change the server in electrum.

I now sent some money to my wallet in multibit but now see that only 4 points after the dot are shown everywhere. While i sent 4 more digits. In fact 8 digits after the point. And i cant change this. Thats not so good.
And then i checked the preferences tab and saw that there is a fee set. I wondered because i sat it to zero before but now i learned that it cant be taken out. Thats not my thing. I believe in bitcoin as a free currency and i dont want to get forced to pay a fee.

How behaves electrum there?

Edit: I found electrum allows zero fee. But are there forced fees included like in official client?
Regarding the reason for fees in multibit... i made a couple of transactions in bitcoin and a fee never helped anything nor did a transaction with the wallet took longer without fees. Maybe fees will be needed someday when mining wont work anymore but at the moment it makes zero difference to have or not to have a fee.

Ok... then it looks more secure. Only downside for me then would be that the words are all english and thats not my native language. I think it would be easier to remember a list of words in ones own language.
So at the end the both clients seems to be really similar and it would come down to what lookalike one likes more.

What about this forced transaction fee the normal client is taking? In the last days i only did 4 transactions. Before that even less. And now it will force me to pay a fee even for small transactions. Is such behaviour implemented in multibit or electrum too?

Glad you like MultiBit.

Note on the Electrum word list the strength comes from the number of words in your passphrase.
I forget the exact length of the word list it uses but it is definitely over a thousand.

With twelve words in the passphrase the total number of possibilities is over:

1,000,000,000,000,000,000,000,000,000,000,000,000

For all practical purposes an attacker would not be able to brute force this.

Re: Litecoin support - I do not have any plans to support this no - mainly as I only ever use BTC.

By the way... any plans to implement Litecoin into Multibit? It looks like its one currency beneath bitcoin that will remain alive isnt it?

I now tested both a bit and i think il use Multibit. I checked out electrum too but this list of words that should lead to getting back your wallet after losing it sounds too risky for me. The number of words seems relatively limited and i think the more wallets are created with this the higher the probability that an attack will get results. I mean an attacker only would need to find all words by creating some addresses and then create a script for chosing them randomly. It looks a bit risky for me.

I like the look of multibit a bit more too so i think i will use it now.

Thanks for the help!

Thanks for the info...

oh that's great. Thanks flatfly, i'll give it a try.  Keep up the good work.

What "stealth" means in this context is defined here: www.portablefreeware.com/faq.php

Your wallet is never stored on a server.  Electrum servers run full bitcoind nodes to serve the blockchain. In theory the worst that a malicious server can do is lie to you about your balance or a transaction, but it can never steal any coins as it doesn't have your private keys.

You're in luck, this feature has just been added (check the main Electrum thread)! It is still under testing though, but if you're comfortable enough with github and feel adventurous, you could try it out. 

Ok, then it loads the normal original blockchain but only stores some of the data. I think thats good and secure. I always wondered where this will go with bitcoin. I mean the blockchain will grow really big in the future. And everyone has to store it when he has a wallet. But this sounds like a good solution here.

@stepkrav... why not using VPN?

electrum seems cool but misses a feature i want : socks proxy support.

For MultiBit the blockchain that is stored to disk only contains the headers of the blocks rather than the full blocks. These are 100 bytes each so the 200,000 blocks are 20,000,000 bytes. I include a copy in the installer which is one of the reasons it can start up more quickly. The main difference is that MultiBit does not store all the transactions, only the ones relevant to you.

(If you did not trust this file - called multibit.blockchain in your install directory - you can delete it and it will download all the blocks again from the genesis block. Takes a couple of hours on wifi).

The only servers MultiBit connects to are the generic Satoshi servers of the bitcoin network (i.e. bitcoind servers). It connects to 4 of these to compare the transactions it receives. When you receive a transaction if you do a right click and 'View transaction details' it will say something like 'Seen by 4 peers' to give an indication of how far through the network a transaction is propagated.

It verifies the integrity of a block (the hash, nonce, difficulty etc) but does not keep track of all the bitcoin network transactions. If you were surrounded by hostile nodes and your network was controlled they could fool you by providing you with incorrect blocks and transactions yes.

This is the Simplified Payment Verification model described in the original Satoshi whitepaper.

I now have loaded the Beta of Multibit. Its portable from the start, thats good. And the loading of the blocks is very fast. Way faster then in the normal network. But the blockchain is way smaller than the original.
So why is it smaller? Is it encrypted or only the last blocks are hold? And it seems the blocks arent loaded normal. Are the blocks loaded from a server and would this hold a securityrisk? I mean when someone would modify this blockchain i load from the server then my wallet would believe it isnt it?

So how secure is this?

Then i loaded the portable version of electrum. Why is it named stealth?
I started it and wanted to create a wallet. But then it asked me to choose a server. So does this mean the blockchain isnt downloaded but instead a chain from a server will be used? Doesnt this have the same risks like multibit in it?
Or is the wallet stored at the server too? I mean then i would need to trust the coder that my wallet is safe there.

Am i too cautious here?

Looks like electrum sounds interesting too... i think i will test both and check what works best.

@jim618 Till now i didnt thought about that. Wallets with one address could be a workaround and deliver what i want... thats right.

Use Electrum and use the expert view.
It's a lightweight client which means you use the blockchain of a server but you still keep the private keys for your adresses on your PC and only on your PC. That means you don't have to download the blockchain before you can use your bitcoins.

Expert view enables you to see how much BTCs are on which address and you can freeze any address to force the client to use the bitcoins of another address which is what you want I think.

blockchain.info never gets access to your private keys.  They are stored on their server encrypted, but the encryption/decryption occurs in your browser, so they cannot steal your coins.

If you want to implement very specific privacy policies like the ones you describe you'd need to do some work on bitcoinj (for multibit). It involves some refactoring and other things that would take time. But eventually I'd like to offer a selection of different coin selection policies.

Seems like you're describing Electrum exactly
Also this chart can help you compare the major clients.

Hi Sebastian,

If you want to keep your addresses separate (for privacy reasons) you can have separate wallets. With MultiBit you can have as many wallets as your like. You can have only one address per wallet and as long as you are careful not to link them with transactions they will be completely separate.

At the moment I advise people to keep onto small amounts of bitcoin in the beta with encrypted wallets (just to be on the safe side whilst it is still being QAed and tested).

Jim

I already have checked armory but it seems its not fully portable and is only an addon for the normal client. So that the normal client has to be used anyway.

Online wallets are too insecure for me. I mean why taking the risk to give another person all your bitcoins only for letting them lay there? That sounds too risky, especially in the bitcoinworld.

Downloading manually might be possible but it takes work and probably some time for downloading too. On top you need to trust the source. But maybe there is a client that does this automatically and in a secure way? So that its faster and secure?

Multibits points sound all nice. I think i will give the beta a try so that i can encrypt the wallet. And ill wait for the feature with the single addresses. Because then its a bit more anonymous because addresses cant be connected together so easily.

Thanks!
Sebastian

multibit or electrum, both are excellent.

Hi Sebastian,

Here is MultiBit's scorecard for your points:


Hello,

im searching an alternative client that has the following settings:

* Way faster synchronizing than the original client. It takes hours to update when you didnt have the wallet open some days. I really dont like that. I now have the client open for hours and it still hasnt loaded 6 days of blocks. I hadnt open the client 12 days. And the blockchain is really big as a file. But for that there isnt an alternative right?
Your initial sync is under a minute. Then (on wifi) it is a couple of minutes to sync a week of blocks.
* Portable
Yes - see http://multibit.org/help_runFromUSBDrive.html
* Opensource so that no hidden code is inside
Yes - source code is at : git://github.com/jim618/multibit.git
* encryptable for security
There is a beta version with encrypted wallets  - it will probably be a couple of weeks before that is put on the main website - there is a bit more test and QA to do yet.
* I want to see exactly how much money is on each ADDRESS (not wallet) i own. So that i can prevent to send 20BTC and in fact 3 transactions are made because the 20BTC are stored on 3 addresses. I want to see the addresses and the money on it so that i can send it from the addresses.
Not at the moment, but it is on my TO DO list.
* And a client that needs the original wallet opened at the same time doesnt sound useful to me too. I mean then i could use the original one instead.
You do not need the Satoshi client installed

Is there such a client that contains all points?

Thanks!
Sebastian

i would use blockchain.info's online wallet. it has an option to sync with a normal bitcoind.

to circumvent the initial downloadphase for bitcoin-qt its possible to download the files manually.

if you really want to have a desktop app:
i am not aware of an offline client which uses the wallet.dat from bitcoin-qt. but i think armory is nice.

Hello,

im searching an alternative client that has the following settings:

* Way faster synchronizing than the original client. It takes hours to update when you didnt have the wallet open some days. I really dont like that. I now have the client open for hours and it still hasnt loaded 6 days of blocks. I hadnt open the client 12 days. And the blockchain is really big as a file. But for that there isnt an alternative right?
* Portable
* Opensource so that no hidden code is inside
* encryptable for security
* I want to see exactly how much money is on each ADDRESS (not wallet) i own. So that i can prevent to send 20BTC and in fact 3 transactions are made because the 20BTC are stored on 3 addresses. I want to see the addresses and the money on it so that i can send it from the addresses.
* And a client that needs the original wallet opened at the same time doesnt sound useful to me too. I mean then i could use the original one instead.

Is there such a client that contains all points?

Thanks!
Sebastian