PayPal 也要提供加密貨幣服務

先是看到「PayPal to allow cryptocurrency buying, selling and shopping on its network」這篇,另外翻到了 PayPal 的新聞稿:「PayPal Launches New Service Enabling Users to Buy, Hold and Sell Cryptocurrency」。

幾個比較重要的地方是,這次會提供的是 BitcoinEthereumBitcoin Cash 以及 Litecoin 這四種:

To increase consumer understanding and adoption of cryptocurrency, the company is introducing the ability to buy, hold and sell select cryptocurrencies, initially featuring Bitcoin, Ethereum, Bitcoin Cash and Litecoin, directly within the PayPal digital wallet.

會先提供美國 PayPal 的使用者使用,然後再展到其他服務以及地區:

The service will be available to PayPal accountholders in the U.S. in the coming weeks. The company plans to expand the features to Venmo and select international markets in the first half of 2021.

另外這次的服務也不是自己跳進去搞,而是透過 Paxos Trust Company 建立起防火牆,所以當加密貨幣那邊出包的時候大概就會切割出來:

The service is enabled in the U.S. through a partnership with Paxos Trust Company, a regulated provider of cryptocurrency products and services.


Stripe 也宣佈要停止支援 Bitcoin 了

Stripe 發了公告出來,要停止支援 Bitcoin:「Ending Bitcoin Support」。預定保留三個月的緩衝期,在 2018 年 4 月 23 日停掉:

Over the next three months we will work with affected Stripe users to ensure a smooth transition before we stop processing Bitcoin transactions on April 23, 2018.


Transaction confirmation times have risen substantially; this, in turn, has led to an increase in the failure rate of transactions denominated in fiat currencies. (By the time the transaction is confirmed, fluctuations in Bitcoin price mean that it’s for the “wrong” amount.) Furthermore, fees have risen a great deal. For a regular Bitcoin transaction, a fee of tens of U.S. dollars is common, making Bitcoin transactions about as expensive as bank wires.

Steam 當時的理由很類似... (參考「Steam 停止使用 Bitcoin 購買遊戲」)

Steam 停止使用 Bitcoin 購買遊戲

Steam 宣佈停止使用 Bitcoin 購買遊戲:「Steam is no longer supporting Bitcoin」。

官方提到的原因是因為交易費用太高 (雖然是讓使用者付):

In the past few months we've seen an increase in the volatility in the value of Bitcoin and a significant increase in the fees to process transactions on the Bitcoin network. For example, transaction fees that are charged to the customer by the Bitcoin network have skyrocketed this year, topping out at close to $20 a transaction last week (compared to roughly $0.20 when we initially enabled Bitcoin).


Historically, the value of Bitcoin has been volatile, but the degree of volatility has become extreme in the last few months, losing as much as 25% in value over a period of days.

所以這樣推測,Steam 不是直接換成法幣?我記得他們合作的交易所 (BitPay) 可以馬上換成法幣...

Bitmain 推出 AI chip

BitmainBitcoin ASIC 市場上算是很有名的,就利用作 ASIC 的經驗推出自己的 AI chip 了:「Bitcoin’s Biggest Tech Player to Release AI Chips and Computers」。

這樣除了可以在雲端上租用 Google Cloud PlatformCloud TPU 以外,也可以自己買硬體來算了 (雖然軟體的支援應該還要再等):「Tensor Computing Processor BM1680」。

Bitmain 的生意愈做愈大了...

Bitmain 做到打算直接弄一座 data center 來挖 Bitcoin:「Chinese firm building 135MW bitcoin data centre」。居然還是用綠色能源來玩出全世界第三大吃電資料中心:

The complex, which will be capable of pulling 135 megawatts of power placing it at #3 of the most powerful data centres in the world, will operate primarily on wind and solar power.

Bitmain 的 AntPool 應該是目前最大的 mining pool:

Bitmain already controls an estimated 18.6% of hashpower worldwide, and many independent miners in the community expressed concern that controlling a massive data centre dedicated to mining bitcoin would give the company too much influence over bitcoin.

關於 AntPool 佔整個 pool 的計算力這邊是寫 18.6%,不過照「Bitcoin Hashrate Distribution」這邊的資料,目前降到 17.4% 了... 而我記得各種攻擊手法中,最低的應該是 25% 的攻擊:「Majority is not Enough: Bitcoin Mining is Vulnerable」,不知道會不會超過... 對於接下來的 release 發出警告 發出了有點摸不著頭緒的警告:「0.13.0 Binary Safety Warning」。 has reason to suspect that the binaries for the upcoming Bitcoin Core release will likely be targeted by state sponsored attackers. As a website, does not have the necessary technical resources to guarantee that we can defend ourselves from attackers of this calibre.


We ask the Bitcoin community, and in particular the Chinese Bitcoin community to be extra vigilant when downloading binaries from our website.

由於 全站走 HTTPS,這是在暗示會出現「不小心發出 的 SSL certificate」的事情?另外官方也建議使用 PGP public key 驗證:

We strongly recommend that you download that key, which should have a fingerprint of 01EA5486DE18A882D4C2684590C8019E36C2E964. You should securely verify the signature and hashes before running any Bitcoin Core binaries. This is the safest and most secure way of being confident that the binaries you’re running are the same ones created by the Core Developers.

來拿板凳蹲著看,順便拉一張目前 certificate 看到的資訊,目前是從 RapidSSL SHA256 CA - G3 簽出來:


在「Kudos - A Peer-to-Peer Discussion System Based on Social Voting」這邊看到分散式的論壇系統,帶有投票分數機制以及相關議題機制:

Decentralized Reddit using a DHT to store content and a blockchain to rank such content. Whitepaper with more details here:

論文裡面可以看出來設計的觀念受到 Bitcoin 的啟發,演算法也是... 換句話說,Bitcoin 帶來的影響遠遠超過金融市場,Bitcoin 所使用的理論也給其他領域很多想法。

如果這樣的系統可行的話 (還沒仔細研究 @_@),真正分散式的論壇系統就會出現了...

在美國政府宣佈贊助非法後,Snowden 取得大量 Bitcoin 贊助

美國政府宣佈資助「反動組織」非法後 (感謝對岸發展出來這個用語,用在這邊還頗適合的),也就代表資助 Edward Snowden 非法。

而這反而引起類似「史翠珊效應」的情況發生,反而造成大量的 Bitcoin 贊助 Edward Snowden:「After Anti-Donation Executive Order, Bitcoin Donations For Snowden Jump」,原始報導出自「After Obama's cybersecurity order threatens Snowden fund, bitcoin donations spike」。

Bitcoin 的「無中央控管」以及「交易不可回退」的特性在這個事件中展現相當大的優點。

Minecraft 與 Bitcoin 的結合?

VentureBeat 的這篇「How Minecraft may make bitcoin the ‘official currency of virtual worlds’」讓人想了一下遊戲的虛擬貨幣與 Bitcoin 的結合...


  • 不需要找金流系統接,Bitcoin 可以直接獨立運作,馬上可以想到不少方法利用 Bitcoin 的架構來規劃虛擬貨幣。
  • 法令更不容易管制,如果遊戲本身再透過 Tor 隱藏在 Tor network 裡的話就更完整。以往在最後要換錢的部份都還會經過金流系統與實體界接,現在連這個部分都避開了。

再來是 Bitcoin 的中立性,跨遊戲之間的交易也許是另外一個可能的強大之處?

不過 Bitcoin 的 n=6 確認應該會讓人感覺到愈來愈痛,不知道後面會怎麼解決...

Bitcoin 電子錢包的初始化加速

因為從以前到現在的歷史記錄都被累積起來,Bitcoin 電子錢包初始化所需要的時間變得很長,所以就有不少方法想要改善。

在「Bitcoin Blockchain Initial Sync Time Dramatically Reduced By Headers-First Sync」這篇文章裡面提到了一些事情。

目前的歷史記錄大約是 22GB,文章裡說平均是兩天可以跑完 (我自己是跑了五天...),但另外一個方法則是可以透過「[ANN] Bitcoin blockchain data torrent」這邊提供的 BitTorrent 方式下載記錄 import 進去,這樣就有機會縮短到 4 小時。

另外被提出來的方案是減少傳輸量先確認。而且這個方法已經被 merge 進官方的 client 了:「Headers-first synchronization」,過陣子來測看看速度如何...