Swarm alpha public pilot and the basics of Swarm

Swarm Alpha Public Pilot and the Basics of Swarm

With the long-awaited geth 1.5 ("let there bee light") release, Swarm made it into the official go-ethereum release as an experimental feature. The current version of the code is POC 0.2 RC5 -- "embrace your daemons" (roadmap), which is the refactored and cleaner version of the codebase that was running on the Swarm toynet in the past months.

What is Swarm?

Swarm is a distributed storage platform and content distribution service; a native base layer service of the ethereum Web3 stack. The objective is a peer-to-peer storage and serving solution that has zero downtime, is DDOS-resistant, fault-tolerant and censorship-resistant as well as self-sustaining due to a built-in incentive system.

How Does Swarm Work?

Swarm is a network, a service and a protocol (rules). A Swarm network is a network of nodes running a wire protocol called bzz using the ethereum devp2p/rlpx network stack as the underlay transport. The Swarm protocol (bzz) defines a mode of interaction. At its core, Swarm implements a distributed content-addressed chunk store. Chunks are arbitrary data blobs with a fixed maximum size (currently 4KB). Content addressing means that the address of any chunk is deterministically derived from its content.

The Swarm Hash

On the API layer Swarm provides a chunker. The chunker takes any kind of readable source, such as a file or a video camera capture device, and chops it into fix-sized chunks. These so-called data chunks or leaf chunks are hashed and then synced with peers. The hashes of the data chunks are then packaged into chunks themselves (called intermediate chunks) and the process is repeated. Currently 128 hashes make up a new chunk. As a result the data is represented by a merkle tree, and it is the root hash of the tree that acts as the address you use to retrieve the uploaded file.

Manifests and URLs

On top of the chunk merkle trees, Swarm provides a crucial third layer of organising content: manifest files. A manifest is a json array of manifest entries. An entry minimally specifies a path, a content type and a hash pointing to the actual content. Manifests allow you to create a virtual site hosted on Swarm, which provides url-based addressing by always assuming that the host part of the url points to a manifest, and the path is matched against the paths of manifest entries.

Ethereum Name Service

In order to authorise changes or publish updates, we need domain names. For a proper domain name service you need the blockchain and some governance. Swarm uses the Ethereum Name Service (ENS) to resolve domain names to Swarm hashes. Tools are provided to interact with the ENS to acquire and manage domains.

Roadmap

Our roadmap is ambitious: Swarm 0.3 comes with an extensive rewrite of the network layer and the syncing protocol, obfuscation and double masking for plausible deniability, kademlia routed p2p messaging, improved bandwidth accounting and extended manifests with http header support and metadata. Swarm 0.4 is planned to ship client side redundancy with erasure coding, scan and repair with proof of custody, encryrption support, adaptive transmission channels for multicast streams and the long-awaited storage insurance and litigation.

Conclusion

Swarm is a powerful tool for decentralized storage and content distribution. With its built-in incentive system, it provides a self-sustaining solution that is resistant to downtime, DDOS attacks, and censorship. The Ethereum Name Service (ENS) provides a crucial bridge between the blockchain and Swarm, allowing for domain name resolution and management. Our roadmap is ambitious, with plans for further improvements and features in the future. As Swarm continues to evolve, it has the potential to revolutionize the way we store and distribute data online.

Source: https://blog.ethereum.org/en/2016/12/15/swarm-alpha-public-pilot-basics-swarm