Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 644BACAF for ; Sat, 1 Sep 2018 00:11:22 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-wm0-f49.google.com (mail-wm0-f49.google.com [74.125.82.49]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id D9BB56CE for ; Sat, 1 Sep 2018 00:11:21 +0000 (UTC) Received: by mail-wm0-f49.google.com with SMTP id f21-v6so6600949wmc.5 for ; Fri, 31 Aug 2018 17:11:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:from:date:message-id:subject:to; bh=p03f81AltqunY9Y22KM+b0KXPjwcaDmBTI7pD29lv7Y=; b=RhrCU7iKed+6M0K9md1ELd+JYPeUvp56vPJOmGzVo8yYJJgsPluNJr6B0MLrhPjXzv F4PxD2tQLQHVEa/E60mY4LRQd5looqkcNVObdMFo61RsQmFvC4ll57znWCR62FpfrSQs prhUzxGxYmPJFlivoTlnAh/4xosDIXTFM/M3Kf267zZzyIgSj6dDbctnEitpR+xxvJJ+ QxgBPIChfilKHC+yql2cJJowGkz9KAJGVZzy373Wk/FwbZrnO/gdY+Vsy28RnG/T0orB VncbMuBW351EhsrWRlLv5iBh3bjk+FiY12wFVGomXcsH2VI9N3H3onx4tLY3B+ngsiUl coJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:from:date:message-id:subject :to; bh=p03f81AltqunY9Y22KM+b0KXPjwcaDmBTI7pD29lv7Y=; b=FPRLRX38Kk5JxC2Xt7mzb9/pnllGIfmb2SoPExK12JmjqTMTnhpOztbBbrlfw1J/l6 DaLIO86wja2+tH+dgrkEjOKerKx2eACF6HeeA6FjEhTWHbb0+Em8OUTAhK7JEBYmPi57 jxvD904YS6pq9+GN076d8feWOZSYhhWwTAqjEAKfIBGWkI9biUoZ6DJ+NprU5bsQ7UEv POq9zihGljdU3WwGv4fT0eKaaU33PcFS/LHu0v/+GFqg7RVK8ILOQfKIWhX02FTWPFOa lThRRr4ozVPfcl4CIgoYC7cy9CzTEMlCpw9uU9EfcmvkUnwxeJm7ePN3c0SNirygsAxc rY7A== X-Gm-Message-State: APzg51D3SQBZFIcqeE8TUGuuwQ2Ts/CTwCAS5KhXYN9wblXd3cXhDU14 2kBQl9yD/SdytLQaSyhgYJcTrBHGeJMBHCVqUGiHOw== X-Google-Smtp-Source: ANB0VdbzEpL1N4KEfdEWQXiIBtXUVE7WkBHMNSLiuvCv9cQEvvENOJvmUYlJ2ihVZ9eHrqHQxFcHf3+swtnU/yQWjUE= X-Received: by 2002:a1c:c345:: with SMTP id t66-v6mr1077920wmf.100.1535760680221; Fri, 31 Aug 2018 17:11:20 -0700 (PDT) MIME-Version: 1.0 Sender: akaramaoun@gmail.com Received: by 2002:a1c:46c6:0:0:0:0:0 with HTTP; Fri, 31 Aug 2018 17:11:19 -0700 (PDT) From: Andrew Date: Sat, 1 Sep 2018 00:11:19 +0000 X-Google-Sender-Auth: gyGd1hCpAtBtv8DvYirPzhbdWkg Message-ID: To: Bitcoin Dev Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Mon, 03 Sep 2018 23:25:52 +0000 Subject: [bitcoin-dev] Selfish Mining Prevention X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Sep 2018 00:11:22 -0000 As I understand, selfish mining is an attack where miners collude to mine at a lower hashrate then with all miners working independently. What are the current strategies used to prevent this and what are the future plans? One idea I have is to let the block reward get "modulated" according to peak hashrate. Say p is the peak hashrate for 365 periods (1 year) consisting of 144 blocks, h is the hashrate of the last 144 block (1 day) period, and r is the base subsidy (12.5 BTC currently). You can then make the max block reward 0.5 r (1 + h/p). So if hashrate is at peak you get the full reward. Otherwise you get less, down to a min of 0.5 r. If miners were to collude to mine at a lower than peak hashrate, then they may be able to do it profitably for 144 blocks, but after that, the reward would get modulated and it wouldn't be so much in their interest to continue mining at the lower hashrate. What flaws are there with this? I know it could be controversial due to easier mining present for early miners, so maybe it would have to be done in combination with a new more dynamic difficulty adjustment algorithm. But I don't see how hashrate can continue rising indefinitely, so a solution should be made for selfish mining. Also when subsidies stop and a fee market is needed, I guess a portion of the fees can be withheld for later if hashrate is not at peak. -- PGP: B6AC 822C 451D 6304 6A28 49E9 7DB7 011C D53B 5647