Blockchains are distributed databases storing an immutable history of cryptographic signature transactions, representing transfers of value on the network. This has brought trust and honesty to entirely decentralized currency, though the detractions to versatility are nearly twofold: blockchains grow rapidly as transaction blocks are added over time, resulting in the current size of the bitcoin blockchain which, at time of writing, is roughly 95 gigabytes. Because of this scalability issue, many regular users cannot run full and independent network nodes because they cannot accommodate the space required to store the entire blockchain, despite it being composed of blocks no bigger than a single MB. This means that though blockchains are very useful for solving certain problems, storing any more complicated data on a blockchain would be enormously inefficient.
Despite blockchains being plagued by this size issue, and having use only for storing tiny cryptographic signatures of transactions and transfers of value, distributed ledgers still have much to offer to the fields of cloud storage and data delivery. Blockchains have proven useful for establishing trust and authenticity for a framework below decentralized applications. Users around the world collectively carry enormous amounts of unused space on many devices. By using blockchain as a decentralized management system on which to build decentralized apps, it is possible to harness this collective storage power to create a field of blockchain based peer-to-peer cloud storage and data delivery networks. On these platforms, users can rent out storage or bandwidth to other users on the network and be compensated for their service offered to the network with crypto assets.
Following is a table comparing several blockchain based peer-to-peer cloud storage and content delivery platforms:
The Internet has become one of the most significant sources for consuming media content in the modern world. To help satiate the voracious demand for web content, Content Distribution Networks are used. These networks of dedicated servers distributed around the globe employ techniques such as edge caching and route optimization to participate solely in uploading and sharing media at lightning speeds, optimizing access to digital content for worldwide internet users. Generally, large companies such as Netflix own specialized content distribution networks composed of many dedicated servers, while smaller businesses can rent content distribution network space from companies such as Akamai.
Another significant service in today’s digital landscape is cloud storage, which will be used by an estimated 1.8 billion users worldwide in 2017. Put simply, cloud storage refers to rentable storage space accessed over the internet. Most online applications already engage cloud storage. For example, documents, images, and emails accessed through web applications like Dropbox or Gmail aren’t stored on your physical machine, they are stored in the cloud. Though cloud storage refers simply to storage offered over the internet, and content distribution networks are servers located geographically to deliver content quickly, combining CDN and cloud storage infrastructure is also common.
Though large companies with datacenters and servers generally lead the cloud storage and CDN space, there has also been an emergence in entirely decentralized distribution networks and storage alternatives used by millions of users around the globe.
For example, Bittorrent, an internet peer-to-peer content distribution protocol, accounted for more than a quarter of all upstream traffic in North America last year, according to a study by Sandvine, a Canadian broadband company. The Bittorrent protocol enables the propagation of “torrent files” using “swarms,” or networks of computers simultaneously downloading and uploading .torrent files without a central coordinating server.
Because Bittorrent downloads are distributed amongst an enormous number of participating peers, controlling this peer-to-peer traffic is far more difficult than blocking traffic coming from official distribution servers. This is the reason Wikileaks releases sensitive content over Bittorrent, and pirating media content proliferates upon the peer-to-peer protocol – the reason Bittorrent has become nearly synonymous with pirating.
Decentralized content distribution, such as that provided by Bittorrent, has very legitimate benefits as well. For example, the Bittorrent protocol is used by organizations to provide alternative downloading methods to their users. Linux distributions are often released over Bittorrent, and the Blizzard gaming company offers a Bittorrent alternative for software updates. Releasing content on peer-to-peer distribution networks is a cheap solution for individuals and businesses, and by distributing bandwidth occasionally offers faster download speeds than centralized servers.
Decentralized datasets and ledgers, also referred to as Blockchains, present additional examples of the great benefits of peer-to-peer technology. Blockchain has revolutionized the way we look at Fintech, realized the concept of decentralized and autonomous organizations, and provided solutions for decentralized supercomputing, to name a few of the many recent innovations. Because data storage, and content and media delivery is becoming ever more distributed, blockchain solutions could revolutionize content delivery, data storage and media platforms as well – which is exactly what the following projects are seeking to deliver to the blockchain space.
DECENT is a decentralized content distribution network designed upon an independent blockchain, targeted towards content creators and authors. Instead of content creators trusting distribution to publishers who often exert influence over artists creative and financial freedoms, the DECENT blockchain assumes this role.
The DECENT blockchain is essentially a blockchain publishing intermediary, handling everything from the secure distribution of media, to the payment of authors and distribution nodes, and maintenance of content creator’s reputations. Content creators release cryptographically secured digital media – ebooks, videos, audio – onto the global DECENT distribution network. Publishing nodes receive and store, distribute and facilitate the unlocking of these files to consumers who’ve purchased them with DECENT tokens, fulfilling the roles of miners on the PoS network.
Publishers handle the creation of transactions on the blockchain to authorize the consumption of content transmitted over the network. When generating blocks, publishers ensure payment is delivered to the author, keeping a portion of the tokens generated as fees for the storage and CPU cycles they contributed to the DECENT network. The first DECENT version uses Bittorrent for file distribution, though future versions may support new technology. The DECENT core team is comprised of 8 members based primarily in Slovakia and China, and more info about the team can be found here.
MaidSafe is a private company located in Scotland that has been developing the SAFE Network since 2006. The SAFE Network is a peer-to-peer network which, using the spare disk space and bandwidth of users in the network, provides distributed and decentralized computing resources and file storage to other users for rent. When uploading files onto the network, private files are fractured into pieces and distributed redundantly across the network. The redundancy provides safety incase nodes leave the network, and security, so that only the owner of the file can recover the pieces scattered throughout the network and decrypt their files.
Safecoins, the digital currency of the network, are generated and distributed to users who allocate storage space and lend it to the network. Safecoins are not stored on any blockchain, and the double-spend problem is instead solved through uniquely generated IDs attached to coins, supervised by Transaction Managers, entities participating in the close group consensus mechanism which replaces the blockchain on the SAFE Network. Safecoins are used to purchase resources on the network.
Though a basic goal for the network is storage, the network may collectively use resources for essential internet functions, giving it the ability to support “every existing service [on] the internet.” For example, using the distributed storage provided by the network, it will be possible to host websites as well. Current web browsers may, after configuration to direct “.safenet” domain requests through the SAFE launcher application, request HTML and other web related resources over the SAFE network to view SAFE hosted websites.
A SAFE browser is in development, and the network also supports a specialized decentralized naming system (decentralized Domain Name System) for locating websites hosted on SAFE. It is essentially an augmented, decentralized and anonymous interpretation of the current internet.
The cost of storage will be based upon the resources available and the relevant demand to consume this storage. , it is “anticipated that storage will be significantly cheaper than using any current solutions… as SAFE does not have many of the overheads and costs of existing services, like Dropbox.” On the SafeNet, you only pay for the resources you use.
Storj is a decentralized cloud storage platform headed by Storj Labs, the company which develops and innovates for the Storj platform. Storj allows users, also known as farmers, to allocate spare space from their hard drive to rent out to other participants in the network, and be compensated for their disk space with the digital coin Storjcoin X. Storjcoin X are counterparty tokens, the protocol which extends the Bitcoin blockchain to accommodate advanced features. Storjcoin X token transactions are therefore stored on the Bitcoin blockchain.
Per the whitepaper, although it uses counterparty assets now, it could accommodate any other token or form of payment in the future.
Users distribute their data to the network in encrypted shards. The shards are stored with redundancy, so that multiple nodes have copies of the same shards so that even if some nodes go offline, users should be able to retrieve their shards and piece together their files. Because the network is distributed and uses storage redundancy, it has higher uptime than centralized and dedicated alternatives. The vast distribution of the peer-to-peer network also leads to faster download and upload times than centralized servers, where data streams may face throttling. Per Storj.io, the cost of storage on Storj is “half the price of the competition,” with rates of $0.015/GB for data storage per month, and $0.05/GB for bandwidth. You only pay for the resources you consume. More info on the Storj team may be found here.
Siacoin is another decentralized cloud storage platform which utilizes the spare hard drive space of network participants for storage. The project is developed by Nebulous Labs, the company behind SiaCoin. SiaCoin employs erasure coding (distributing encrypted fragments of data redundantly across the network) and an independent blockchain with tokens known as SiaCoins, to support the network.
Hosts and renters engage in file contracts, an agreement between the storage provider and the consumer, before providing storage. The consumer pays the SiaCoins upfront to the blockchain, which acts as an escrow service, with the previous contract being the rules for arbitration. If the contract is met and the storage provider submits a proof of storage, the storage provider is compensated. Otherwise, the coins are returned to the renter.
Anyone with spare storage may participate and earn SiaCoins after downloading the Sia client. Hosts set and advertise a price shown to renters seeking storage, after which they may collect file contracts from users who are comfortable with storage and said price. This competitive nature helps keep prices low, close to the raw price of storage, vs. the higher prices offered by centralized cloud storage companies. SiaCoin only charges for the actual storage you use. Because the price of storage is determined by the free market, price tends to fluctuate, as the value of SiaCoin is also subject to market forces and speculation.
The SiaCoin site reads that “as of January 2016, storage is about $2.25/TB/month with 6x redundancy,” though actual prices are somewhat different. Siapulse.com seems to track market rates and price conversions (not an endorsement, no guarantees of accuracy). The SiaExplorer from the official Sia domain also allows blockchain exploration, where some basic metadata regarding contracts and transactions may be viewed. The Sia whitepaper may be found here.
BlockCDN is a blockchain based content delivery platform, planning to put to use idle network resources to provide cheap CDN services. In the BlockCDN peer-to-peer economy, users may rent out their spare bandwidth and storage to act as cache servers in the network, participating in uploading content at high speeds from optimal geographical locations to internet users who consume content from BlockCDN customers. Cache servers store, or ‘cache’ content such as web pages, files, etc, and participate in uploading those files to internet consumers.
Per the BlockCDN whitepaper, BlockCDN makes use of Squid, the open source “caching and forwarding web proxy” software. The company leading the BlockCDN development also plans to develop cloud computing and storage in the future. BlockCDN allows users to purchase CDN bandwidth using BCDN tokens, the digital asset stored on the BlockCDN blockchain which fuels the peer-to-peer economy. The network software intelligently pairs consumers with users renting bandwidth, to help provide fast global content delivery at competitive rates.
According to BlockCDN.org, CDN bandwidth purchased over BlockCDN rates are only 10% of those offered by large competitors, going for as low as $0.0072/GB. The BlockCDN blockchain is based upon the Ethereum Network. The company appears to be based mainly in China and the U.S, some info on the team may be found here.
IPFS, or the InterPlanetary File System, is a next generation peer-to-peer, content-addressable distributed file system, combining successful aspects of related projects from open source and academia over the years. Note that according to the whitepaper, “aside from BitSwap… the main contribution of IPFS is” the successful amalgamation of past projects which include “DHTs, BitTorrent, Git, and SFS.” In other words, nodes participating within the IPFS network form an enormous and resilient distributed file sharing system employing distributed hash tables as employed by Kademlia, version control as in Git, block exchange as in Bittorrent, with Self-certifying File System capabilities. With the above properties, IPFS enables a sophisticated, resilient, global file sharing and versioning environment which curates and removes duplicates for efficiency, while simultaneously supporting rapid lookups and low latency access to data. The network “has no single point of failure” and is trustless – peers needn’t trust each other to ensure their files integrity – whilst ensuring old and important files aren’t lost in the sea of data. The software stack is designed without a reliance on the IP protocol, and can function over other network protocols, using a versatile and tailor-made decentralized naming protocol called IPNS.
The IPFS network uses the Bitswap protocol to incentivize participation and not a virtual currency, though a virtual currency implementing a “bitswap strategy… will be explored in a future paper”. Bitswap drives the distributed file sharing economy with a unique “barter system” where nodes are required to share data blocks with or seek blocks for other nodes if they wish to download from said node. This system ensures mutual, reciprocated downloading, eliminating the idea of free loading “leeches” like on Bittorrent, keeping nodes incentivized to cache and distribute data “even if they are not interested in them [the data blocks the node shares as barter tender] directly”.
Via the whitepaper, IPFS is at least “a global, mounted, versioned filesystem and namespace”, a “next generation file sharing system.” However, its design is ambitious, and it has the potential to disrupt old and established file sharing protocols such as HTTP. For example, by allowing those interested with online content to accommodate the content hosting and distribution required by participating on the IPFS network, IPFS could support entire websites and distribution networks, “push[ing] the web to new horizons.” Read the whitepaper here.
(This article is not an endorsement of any products, but simply a summation of content found researching the internet)
 A Bittorrent protocol file which contains metadata regarding files and folders to share, among other controls for the protocol, including important networking addresses and relevant data.
 Downloading materials illegally reproduced online for free, without paying the respective creators of the content.