This month I'm spending some time researching altcoins. I'm posting my notes here on!


Siacoin is an altcoin that powers Sia, a decentralized cloud file storage network. Think of it as a decentralized version of Amazon S3. With Siacoin you can rent storage, or you can rent out your storage space and receive Sia.
The name Sia is a nod to the Egyptian god of perception.

Tech Notes

  • Sia uses a Proof of Work algorithm
  • Sia is a bitcoin derivative with contract support and an M-of-N multi-signature scheme.
  • Contracts are agreements between hosts and clients to store files. Files are replicated with a Reed-Solomon algorithm to ensure availability even if multiple hosts go offline. Sia also has the ability to recover/replicate to other hosts if the original file is deleted and there are only a few hosts left on the network.
  • Contracts are enforced by verifying proof of storage with Merkle tree hashes and random encrypted segments of the stored files. Hosts are rewarded for submitting proof and penalized for missing proofs.
  • Both hosts and clients submit funding to start a contract. Client money is used to pay the host for storing files, host money is a deposit, which is forfeited if they don't complete the contract.
  • Full encryption, and only the storage renter has decryption keys.
  • Block time is 10 minutes and there is a minimum of 30,000 coins per block.
  • Sia developers want to eventually peg Sia to Bitcoin with a two-way peg, which enables you to change Sia with Bitcoin at a fixed rate.


  • Sia advertises lower file storage costs than Amazon S3 and Microsoft Azure.
  • 100% Open Source, with named and known founders
  • It is in active development with a public roadmap and regular releases.
  • Openness on their blog in the face of some major code bugs. Regular updates.
  • Integrations with an existing apps that allows you to back up your full machine. This is important for user adoption.

Getting Siacoin

  • Siacoin is currently #22 on the market cap list and trading at around $0.07 USD.
  • The two main places to get Siacoin right now are Bittrex and Shapeshift.

Maybe Sia will do what Storj tried to do but couldn't. I look forward to having a static site hosting component available!

  spent 20.0¢
I was quite into Storj for a while, until it went Ethereum and around that time I believe a switch up in devs or some left or something, either way the move to Eth took away my interest in the coin or tech itself, but always heard about Sia and just never checked it out further. Thanks for this little write up, I hope I remember to check out even further.
   3yr ago