<p>I do not agree with the assumptions.</p>

<p>In the Bitcoin network, the average block time is also a function of the difficulty, <em>approximately</em>:</p>

<pre><code>(P*d)/p = 10 minutes
</code></pre>

<p>Where P is the average number of hashes to obtain a new block in 10 minutes (if d=1 and p=1 at base - it wasn't - then P=600), d is the current network difficulty and, p is the current network hash rate per second.</p>

CC BY-SA 3.0
2018-03-10T06:03:38.877Z
2018-03-10T06:03:38.877Z
Willtech
<p>Presuming the honest network and the attacker both perform honest mining, the expected time till the honest network finds a block is T/p. </p>

<p>T is the expected time until any participant in the network finds a new block, p is the hash power of the honest network. </p>

<p>pT makes absolutely no sense since this would mean that a low hash rate will make you find blocks fast. In fact a participant with a mining power of 0 would be able to find a new block in 0*T = 0 time.  </p>

CC BY-SA 3.0
2017-10-05T20:03:17.477Z
2017-10-05T20:03:17.477Z
greenphone
<p>let p be the hash rate that belongs to honest network and T be the time a block is found. In the Bitcoin paper it's said "assuming the honest blocks took the average expected time per block...". In another <a href="https://arxiv.org/pdf/1701.03977.pdf" rel="nofollow noreferrer">paper</a> it's said this average time is T/p. </p>

<p><strong>Question</strong>: What is the average time for an honest network to find a block?</p>

<p>If it's T/p, why?</p>

<hr>

<p>I think, </p>

<p>if p+q=1, where q is an attacker's hash rate and a block is found with the full hash rate: H, in T time. Then for an honest network, it would take, pT (not T/p).</p>

<p>Am I missing something?   </p>

<bitcoin-core><doublespend>
What is the average time for an honest network to find a block when its hash rate is p?
Aydin
# What is the average time for an honest network to find a block when its hash rate is p?

(Asked by: username_0 on 2017-10-05)

let p be the hash rate that belongs to honest network and T be the time a block is found. In the Bitcoin paper it's said "assuming the honest blocks took the average expected time per block...". In another [paper](https://arxiv.org/pdf/1701.03977.pdf) it's said this average time is T/p.

**Question**: What is the average time for an honest network to find a block?

If it's T/p, why?

---

I think,

if p+q=1, where q is an attacker's hash rate and a block is found with the full hash rate: H, in T time. Then for an honest network, it would take, pT (not T/p).

Am I missing something?

**Tags:** bitcoin-core, doublespend


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## 2 answers

### Answer by username_1 on 2018-03-10. Score: 1

I do not agree with the assumptions.

In the Bitcoin network, the average block time is also a function of the difficulty, *approximately*:

```
(P*d)/p = 10 minutes

```

Where P is the average number of hashes to obtain a new block in 10 minutes (if d=1 and p=1 at base - it wasn't - then P=600), d is the current network difficulty and, p is the current network hash rate per second.


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### Answer by username_2 on 2017-10-05. Score: 0

Presuming the honest network and the attacker both perform honest mining, the expected time till the honest network finds a block is T/p.

T is the expected time until any participant in the network finds a new block, p is the hash power of the honest network.

pT makes absolutely no sense since this would mean that a low hash rate will make you find blocks fast. In fact a participant with a mining power of 0 would be able to find a new block in 0\*T = 0 time.


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