Botnets v Bitcoin | Python Fiddle

import itertools

# Convenient units and constants
MH_s = 1e6
GH_s = 1e9
TH_s = 1e12
COIN_MONTH = (525600.0 / 12 / 10)

# https://blockchain.info/charts/hash-rate on 2017/03/01
NETWORK_RATE = 3.35e6 * TH_s
# http://www.coindesk.com/price/ on 2017/03/01
DOLLAR_COIN = 1225

def per_coin(hashrate):
    """Chance to get any given coin."""
    # Assumed to be CPU previously not part of network
    return hashrate/(hashrate+NETWORK_RATE)

def exp_dollars_month(hashrate):
    """Expected monthly earnings."""
    return per_coin(hashrate) * COIN_MONTH * DOLLAR_COIN
    
def exp_months_coin(hashrate):
    """Expected months until minting >0 coins."""
    return 1.0 / (per_coin(hashrate) * COIN_MONTH)

def summarize(botnet_sizes, bot_hashrates):
    for botnet_size, bot_hashrate in itertools.product(botnet_sizes, bot_hashrates):
        print '-'*20
        print 'Botnet size = %.1E, bot hashrate = %.1E' % (botnet_size, bot_hashrate)
        hr = botnet_size * bot_hashrate
        print 'Total strength = %.1E' % hr
        edm, emc = exp_dollars_month(hr), exp_months_coin(hr)
        print 'Expected dollars / month = %f' % edm
        print 'Expected months until first coin = %f' % emc

# https://en.wikipedia.org/wiki/Botnet#Historical_list_of_botnets
# - 3e7 was largest in table of botnets
# - Probably 1e4 or 1e5 are much more typical
# https://en.bitcoin.it/wiki/Non-specialized_hardware_comparison
# - CPUs were on the order of 5s or 10s of MH/s
# - GPUs could get up to the 1s of GH/s, but most were on the order of 100s of MH/s
summarize([1e4, 1e5, 1e6, 1e7, 1e8],
          [10*MH_s, 100*MH_s, 500*MH_s])

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