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jav

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trysia.tech 4y ago

Before Filecoin, there was Sia: Try a hands-on demo of its file storage tech

jav
3pts0
trysia.tech 4y ago

Hands-on demo of Sia's decentralized storage tech

jav
3pts0
siasky.net 5y ago

Hosting a mirror of the English Wikipedia on Skynet for $3/month

jav
2pts0
siasky.net 5y ago

The IPFS Wikipedia mirror is from 2017; an up-to-date snapshot is now on Skynet

jav
1pts0
siasky.net 5y ago

Wikipedia mirror on Skynet (Kiwix-based)

jav
1pts0
www.ethereumpyramid.com 10y ago

What is Ethereum, 2nd gen. cryptocurrency, good for? – a visual example

jav
2pts0
www.ethereumpyramid.com 10y ago

What is Ethereum, the 2nd gen. cryptocurrency, good for? – a visual example

jav
3pts0
ethereumpyramid.com 10y ago

Ethereumpyramid.com – visualizing the state of an Ethereum pyramid contract

jav
1pts0
www.youtube.com 11y ago

Offline Bitcoin wallet completing a payment via NFC and Bluetooth [video]

jav
1pts0
signup.thebitcoinbox.com 11y ago

Bitcoin payment terminal combines NFC and Bluetooth for offline payments

jav
2pts0
www.coindesk.com 12y ago

How Hive’s New Web Wallet Attacks Bitcoin Adoption Roadblocks

jav
1pts0
www.bridgewalkerapp.com 12y ago

My acquired Bitcoin startup Bridgewalker is now open source

jav
45pts10
www.youtube.com 12y ago

Video of a Bitcoin point of sale solution using NFC for contactless payment

jav
2pts0
www.bridgewalkerapp.com 12y ago

Using Bitcoin, NFC and Bluetooth to make a mobile euro payment in 15 seconds

jav
3pts0
www.bridgewalkerapp.com 12y ago

Bridgewalker: an exchange rate adjusted Bitcoin wallet (now with short demo)

jav
1pts0
www.bridgewalkerapp.com 13y ago

Bridgewalker: an exchange rate adjusted Bitcoin wallet

jav
25pts10
bit-pay.com 14y ago

Bitcoin mobile checkout solution from Bit-Pay [video]

jav
2pts0
www.youtube.com 14y ago

Bitcoin: Point of sale system - video of demo payment

jav
1pts0
www.youtube.com 14y ago

Demonstration of a simple Bitcoin point of sale solution

jav
2pts2
www.bitcoinmonitor.com 15y ago

Visualization of the activities at a Bitcoin node

jav
12pts3
bitcoinmonitor.com 15y ago

No central authority needed: Bitcoin is a p2p digital currency. See it in action

jav
1pts0
www.bitcoinmonitor.com 15y ago

Bitcoin is a p2p-based digital currency. This site visualizes the network state.

jav
4pts0

It does use Mt.Gox in the background for the actual exchange process. There is not enough volume (yet) to make an internal exchange practical, there would be too much risk at the moment, at least for my taste.

When I started on this project, Mt.Gox was pretty much the only choice, because of the large market share (> 80% at the time) and the necessary volume and small enough market spread. Their withdrawal delays are annoying, that's true. It does not affect me directly, since it's only Bitcoin in and Bitcoin out for me, where so far Mt.Gox had pretty much never delays. But it does distort the market price, which means you get a great rate when you fund your Bridgewalker account (because BTC is overvalued on Mt.Gox) and get a bad rate when you spend it (again, because BTC is overvalued on Mt.Gox) - so in the end it kind of zeroes out for you as a user, but it's still confusing for the user, why you have this offset.

There aren't many alternatives though. Bitstamp could be one, but I'm worried that they still might run into regulatory issues down the line. Also none of the other exchanges offer real-time streaming updates about changes to the order book, like Mt.Gox does, which is very useful to keep track of the market. Kraken could be an interesting alternative to Mt.Gox, since they seem to run a solid operation. If they add such a streaming API with real-time updates about the order book and maybe get some more volume, then I would consider switching the backend over.

Or someone else does it first - it's open source now, after all! ;-)

Or maybe you could hedge the whole thing just with some financial swap construction, but I haven't looked into that too much and it's not my area of expertise. I would be interested to find out how much something like that would cost in terms of overhead/fees and who would be a partner to provide such financial services for Bitcoin. If you have some input regarding this, feel free to contact me - my email address is on the Bridgewalker website.

No, you cannot use this app to buy bitcoins. So I'm afraid it does not solve one of the hardest challenges Bitcoin still faces, which is how to get any. You'll have to figure out the best/cheapest way depending on where you are.

If you happen, for example, to stand in front of a Bitcoin ATM, you can use that to turn fiat that you have in the form of cash into fiat that you have in your Bridgewalker account (by buying Bitcoin from the ATM and sending it to your Bridgewalker address), which you can then later spend wherever it says "Bitcoin accepted here".

A lot of exchanging back and forth for sure, but basically the idea of "Bitcoin only as tranfer mechanism" applied at every step. It's also just a technical prototype. In practice it might make sense to cut some of those exchange fees by having a more direct way to fund your account, at the cost of only being available in certain markets/countries. For this prototype I went with the easiest solution: only Bitcoin in, and Bitcoin out.

Some background: It's an Android wallet, where you maintain a euro balance (held by Bridgewalker for you). Using those funds, bitcoins will be bought at current market price whenever you want to send any. This allows you to use Bitcoin only as a payment mechanism, without being affected by the exchange rate volatility. You fund your account via Bitcoin as well, which will be exchanged for euros at current market price and credited to your account.

So: Bitcoin as transaction mechanism, Euro as store of value.

[dead] 15 years ago

This comes from this forum post: http://forum.bitcoin.org/index.php?topic=782.0

The problem was, that transactions can have "change". So by sending 1 BTC, the client did in fact send 1 BTC to one address and the remaining 8999 BTC to a a newly generated address which is automatically added to the wallet. Since the backup was before this transaction, the backup didn't include the private key to the change address and 8999 BTC were lost.

A really unfortunate incident, as the person simply didn't know this technical detail. It prompted some upgrades to the client, which now generates addresses in advance and stores them in the wallet. When new addresses are needed, the ones from this pool are used first. With a recent client this accident would not have happened. It's still important to know though, that after _sending_ Bitcoins, a wallet might potentially include new private keys that are not in an old backup (if the pool has been completely used up since the last backup).

By the way: All this happened in August 2010, so this wasn't $81,000 at the time.

My guess would be that these are payouts from a mining pool. People pool their hashing capacity to collectively find a new block worth 50 BTC and the pool then splits the reward between the participants. Some pools probably do this payout step on a fixed schedule.

On the other hand, most pools have moved to include several recipients into a single transaction, so if it is a pool, it's somewhat "outdated".