Theta is a decentralized platform for streaming videos. It has made headlines recently, especially after the launch of the Mainnet 2.0, for the high profile of its partner companies, including Samsung, which will implement Theta TV on all top-of-the-range Samsung smartphones, and Google, which through Google Cloud will become an Enterprise Validator and allow users to execute and distribute nodes directly from the Google Cloud Marketplace.
This news has boosted the value of the Theta crypto and made the project more solid than ever.
What is Theta?
Theta is a decentralized video streaming and distribution network. Through the use of ERC20 tokens, it incentivizes and encourages users to share bandwidth, excess resources and forward video streams. This system improves the quality of stream delivery and solves distribution and content delivery problems, especially for high resolution and high-speed streams (8k, VR360), and significantly reduces network costs, video platforms no longer need to build expensive infrastructure.
Theta solves the main problems of traditional CDN (Content Delivery Network) networks, which use POPs (Points of Presence) to optimize the quality of streaming, but are faced with the so-called “last mile problem” due to the limited number of POPs, especially in less developed countries.
We can imagine the Theta network as a “World cache” formed by the memory resources and bandwidth provided by users, in which all viewers can contribute with their devices through “cache nodes”, forming a mesh network for video delivery. This system solves the ‘last mile problem’, since nodes, being closer to each other than POPs, allow higher transmission and lower costs, relating to bandwidth, reducing its use in favour of cache nodes. In addition, decentralized systems, through mesh networks, offer greater scalability in terms of the number of people connected to the network.
Architecture and consensus in Theta
The protocol of Theta is based on a proof-of-stake consensus algorithm integrated with a multi-level BFT (Byzantine Fault Tolerance) protocol
In order to achieve a good balance between scalability and decentralization, suitable for the purpose of video streaming, the system consists of a validation committee of 10 to 20 nodes, with the task of producing high-speed blocks, followed by a pool of participating nodes called “guardians” with the task of finalizing the blockchain. The system requires 2/3 of the guardians to agree before finalization.
The main idea is to have a small set of validation nodes, to produce a blockchain as quickly as possible, with a high degree of difficulty to prevent attacks that compromise the integrity of the blockchain and to reduce the risk of network forking.
The guardian nodes are then called upon to finalize the chain, generated by the validators. By “finalization“, it is meant convincing 2/3 of the guardian nodes to accept the same blockchain. As we shall see, this is done thanks to the aggregate signature gossip scheme. The guardian nodes maintain the decentralization level of the network.
Aggregate signature gossip scheme
Transmitting the entire hash of the block to the guardian nodes would result in an overload, due to the large number of guardian nodes relative to the validator nodes, compromising their speed. Therefore, Theta uses the gossip protocol, requesting each node to continue combining the partially aggregated signature from the neighbouring node (instead of the entire hash) and thus continue spreading the signature. This speeds up communication between nodes while keeping message sizes small.
Turing complete smart contract support
There is a Turing complete smart contract runtime environment that is fully compatible with the Ethereum Virtual Machine (EVM). The aim is to use Ethereum’s large family of developers and allow its pool of experts to work on it. The smart contracts will allow optimizing the efficiency of the platform:
- customized content and functionality for content creators and users
- different payment options
- special events and loyalty programs
How can Theta be used?
Use cases vary according to the needs of the actors involved in the ecosystem, smart contracts can be used by content creators, viewers and platform providers to customize mechanisms that require the use of tokens. Here are some examples:
cache storage nodes, earn from recording caches, transferring video streams to other viewers.
Viewers can earn tokens from advertisers as engagement rewards and in turn reward preferred content creators.
Streaming sites and platforms can increase and generate new revenues from the sale of premium goods and services and from the increased engagement of new viewers through Theta.
Advertisers fund advertising campaigns with tokens to support streaming sites, influencers and viewers.
Streaming platforms can offload up to 80% of their CDN costs.