<p>Hashcash with SHA256 is about the best possible compute bound proof-of-work.</p>

<p>In a memory bound proof-of-work (which Litecoin's is not), like my <a href="https://github.com/tromp/cuckoo" rel="nofollow">Cuckoo Cycle</a>, memory latency, rather than computation, is the bottleneck, thus turning commodity DRAM into the ASIC.</p>

CC BY-SA 3.0
2015-07-27T22:40:16.443Z
2015-07-27T22:40:16.443Z
John Tromp
<p>Contrary to the name the proof of work used in Litecoin is significantly more difficult than SHA256 to verify (it slows sync times noticeably), while simultaneously not achieving it's goals of being only able to be mined on <a href="https://web.archive.org/web/20120207123851/http://litecoin.org/">a CPU</a>, or <a href="https://web.archive.org/web/20130601173957/http://www.litecoin.org/">a GPU</a> depending when you read the pitch on their website. It offers very little resistance to being mined on a GPU or ASIC, in fact its design is extremely well tailored to linear time-memory tradeoffs, which make the hardware cost even cheaper. Being harder to make an ASIC for isn't an asset either, it just means that they become less commodity hardware and more likely a monopoly of one or two players. </p>

<p>SHA256 is about as lightweight and as simple as you can get, avoiding hardware acceleration is not an achievable goal and probably not even desirable even if it were. </p>

CC BY-SA 3.0
2015-04-28T14:07:20.623Z
2015-04-28T14:38:35.907Z
2015-04-28T14:38:35.907Z
Claris
<p>I know litecoin was created back in the day using Scrypt as to make it more lightweight but also harder to build ASIC hardware from - so everyday computers could mine. Are there other algorithms one should be aware of nowadays? Possibly ones that require little resources and make it impractical to build ASICs.</p>

CC BY-SA 3.0
2015-04-28T13:31:59.880Z
It's never *impossible* to build an ASIC for any given POW. After all, an ASIC is just a computer which happens to be application-specific. If it's "impractical to build ASICs" for a given POW, then only the super-rich will be able to build/purchase and subsequently operate such ASICs. If your goal is to minimize centralization *in the long term* (assuming that ASICs will eventually appear for any popular POW), then using simple algorithms which can be easily/cheaply implemented in ASICs should be your target.
Christopher Gurnee
CC BY-SA 3.0
2015-07-28T12:12:18.447Z
@ChristopherGurnee: That should probably rather be an answer.
Murch
<alternatives><proof-of-work><algorithms><mining-technical-details><asic-resistance>
What is the most lightweight proof-of-work algorithm?
Luca Matteis
# What is the most lightweight proof-of-work algorithm?

(Asked by: username_0 on 2015-04-28)

I know litecoin was created back in the day using Scrypt as to make it more lightweight but also harder to build ASIC hardware from - so everyday computers could mine. Are there other algorithms one should be aware of nowadays? Possibly ones that require little resources and make it impractical to build ASICs.

**Tags:** alternatives, proof-of-work, algorithms, mining-technical-details, asic-resistance

> **Comments:**
> **username_1**: It's never *impossible* to build an ASIC for any given POW. After all, an ASIC is just a computer which happens to be application-specific. If it's "impractical to build ASICs" for a given POW, then only the super-rich will be able to build/purchase and subsequently operate such ASICs. If your goal is to minimize centralization *in the long term* (assuming that ASICs will eventually appear for any popular POW), then using simple algorithms which can be easily/cheaply implemented in ASICs should be your target.  
> **username_2**: @username_1: That should probably rather be an answer.  

---

## 2 answers

### Answer by username_4 on 2015-04-28. Score: 7 | Accepted answer

Contrary to the name the proof of work used in Litecoin is significantly more difficult than SHA256 to verify (it slows sync times noticeably), while simultaneously not achieving it's goals of being only able to be mined on [a CPU](https://web.archive.org/web/20120207123851/http://litecoin.org/), or [a GPU](https://web.archive.org/web/20130601173957/http://www.litecoin.org/) depending when you read the pitch on their website. It offers very little resistance to being mined on a GPU or ASIC, in fact its design is extremely well tailored to linear time-memory tradeoffs, which make the hardware cost even cheaper. Being harder to make an ASIC for isn't an asset either, it just means that they become less commodity hardware and more likely a monopoly of one or two players.

SHA256 is about as lightweight and as simple as you can get, avoiding hardware acceleration is not an achievable goal and probably not even desirable even if it were.


---

### Answer by username_3 on 2015-07-27. Score: 2

Hashcash with SHA256 is about the best possible compute bound proof-of-work.

In a memory bound proof-of-work (which Litecoin's is not), like my [Cuckoo Cycle](https://github.com/username_3/cuckoo), memory latency, rather than computation, is the bottleneck, thus turning commodity DRAM into the ASIC.


---

