You may find it strange when you see the title: AO stands for Hyper Parallel Computing, and Nostr is a decentralized social protocol. These two seem to belong to completely different fields and are not easy to compare. However, if we go deeper into the technical implementation level, we will find that they are essentially "message transmission protocols", so they are comparable.

As a message transmission protocol, the core element is naturally the "message" itself, and everything revolves around the transmission of messages. So in the AO and Nostr networks, how are their respective messages defined? How is their network architecture that supports message transmission built? How can they be integrated with other protocols? What are their respective positioning, main application scenarios, and development trends?

This article aims to conduct an in-depth comparison between the two protocols, AO and Nostr, focusing on the impact of protocol structure on functionality and conducting a detailed analysis around the above issues.

1. Concept and Characteristics of Messages

1. Message in AO

In the AO network architecture, a message is the basic information unit transmitted between network units (MU, SU, CU) or between processes. They achieve information exchange and collaboration by sending and receiving messages.

AO is designed as a message-driven asynchronous communication network. First, AO needs messages to drive when starting work (starting a process), and these messages can come from external users or other processes. Secondly, AO's inter-process communication is asynchronous, which means that the sending and receiving of messages are independent of the operations of the sender and receiver. The process sending the message does not need to wait for a response or acknowledgment from the receiver and can immediately continue performing other operations. This feature significantly improves the efficiency of AO parallel computing.

The asynchronous transmission and no-wait nature of messages in an AO network makes it ideal for handling large-scale parallel computing tasks, as it allows parts of the system to execute in parallel without having to wait for a long time for responses from other processes.

In AO, every message adheres to the Arweave ecosystem’s ANS-104 standard, a data packaging protocol. ANS-104 significantly improves data read and write throughput by binary serializing multiple transactions into one native transaction. This protocol is not just a simple data packaging, but also adds fields such as owner, signature, target address, label, and data to the packaged data. This design enables ANS-104 to support a variety of data types, including documents, pictures, audio and video, games, data models, program codes, and holographic states. In addition, it also supports data ownership and signature verification, providing guarantees for data security and integrity.

These features of the ANS-104 standard are particularly important to AO because they enable AO to build diverse application scenarios for different data types. The unified message format also greatly facilitates efficient communication and seamless collaboration between processes, and can also improve the efficiency of storage and settlement processing on Arweave, allowing AO to effectively build a data availability layer and data consensus to support its wide range of application needs.

2. Events in Nostr

In the Nostr protocol, a standard message format based on the JSON structure is used to describe various types of data. This message format is called an event, which is the basic data object in the Nostr network.

The most commonly used message structures are being integrated into a commonly followed standard, called the NIPs (Nostr Implementation Possibilities) protocol standard. This consistency and standardization greatly improves the efficiency of data processing and management, and helps to enhance the interoperability and stability of the system. Through NIPs, users can perform various operations and interactions in the Nostr network without worrying about differences or incompatibilities in data formats.

The JSON structure is used to define the event data format in the Nostr protocol. This structure contains different fields, each of which has a different function. For example:

  • Pubkey field: represents the public key of the user who sent the event, which is used to identify the user. This public key will be used to digitally sign the event to ensure the authenticity and integrity of the event.

  • kind field: used to indicate the type of event. It can represent different message types, such as chat room messages, wallet information, etc., or it can represent specific user behaviors, such as recommending a relay list, performing an action, etc.

  • Content field: contains the specific content of the event. This field supports a variety of data types, such as social media posts, papers, audio and video, etc. Users can express the various information and data they want to convey here.

  • sig field: used to store the digital signature of the event. This signature is generated by the sender using their private key and then verified by the recipient's client using the corresponding public key. The signature ensures that the user with the corresponding public key actually sent the event on a specific date, thereby enhancing the credibility and verifiability of the event.

  • ……

For a detailed description of the event data structure, see: https://nostr.how/zh/the-protocolcontent. The Nostr protocol provides a clear framework for sending, receiving, and verifying events through these fields and structures. This design helps ensure the security, consistency, and reliability of data.

All fields are combined to express a complete event that plays a specific role. In general, an event is a data structure containing arbitrary content and signed by the user, which reflects the location, characteristics and role of Nostr:

  • Nostr is an information publishing, storage and receiving system. By adopting the JSON structure and NIPs protocol standard, Nostr has established an efficient data exchange and management framework, ensuring the consistency and parsability of information, and providing users with a stable, reliable and unified information communication environment;

  • Support for client verification: The data structure supports verification on the client, so there is no need to trust any relay server or third party, and the authenticity and integrity of the event can be verified directly.

  • Building a decentralized, censorship-resistant, and verifiable social network: The properties of this data structure allow Nostr to serve as a decentralized platform where users can freely communicate and share information without worrying about censorship or information tampering.

2. Network structure supporting message transmission

1. AO: MU/SU/CU form a collaborative network

The AO network consists of three modular basic units: MU, SU, and CU, and operates and collaborates through messages and processes. Its network architecture is shown in Figure 1-1.

Figure 1-1: Modular and collaborative network units form the AO network architecture (Image from the AO white paper)

A process is a computing unit in an AO network. Starting an application on an AO is equivalent to starting one or more processes. The system allocates and schedules resources, such as MU, SU, CU, virtual machines, memory, etc., for each process to execute the process:

  • MU (Messenger Unit): This is the messenger unit, which is responsible for sending information to the appropriate SU for processing, and then delivering it to the CU for calculation. The calculation results are then returned to the SU, and the messenger unit repeats this process continuously;

  • SU (Scheduler Unit): This is the scheduling unit, responsible for scheduling and message sorting, and uploading messages to Arweave;

  • CU (Compute Unit): This is a computing unit that receives messages, performs calculations, and implements state transitions.

As mentioned above, the network structure and operation mode of AO show that:

  • AO is a messaging system

Messages are the core elements of a process and the only working objects of MU, SU and CU. The entire process revolves around messages. A process is the running activity of a message collection, which includes the complete process from receiving messages, message transmission, message scheduling and sorting, executing calculations (message state conversion), and outputting and storing calculation results.

Therefore, AO is a message transmission system that can be dedicated to building applications in information publishing, real-time communication and interaction, content distribution, etc., such as decentralized social networks, social media, and decentralized audio and video on-demand/live streaming platforms.

  • AO is a super parallel computing network

AO is a modular network in which computations are performed off-chain and are not constrained by block consensus, allowing computing units (nodes) to be infinitely expanded as needed, greatly improving computing performance.

In the AO environment, any number of computing tasks (parallel processes) can be started at the same time. These processes can run independently on different computing nodes and complete verification locally. This makes AO a distributed, verifiable, super-parallel computer.

Although each computing process can run independently on different nodes, they can communicate and collaborate through a unified information format (ANS-104), which connects the independently running computing processes together to form a unified network.

  • AO is an open platform

The core of AO is a message protocol that allows different applications running on Arweave to communicate with each other. Each application can send information to other applications through the AO network, use AO to perform combinatorial operations, and realize cross-chain information exchange.

The AO network runs off-chain and can seamlessly connect with Web2 applications. By calling the AO protocol interface, Web2 applications can participate in this decentralized network. This feature enables AO to eliminate the barriers between Web2 and Web3 applications, and achieve trusted information exchange and interoperability between applications. AO's communication protocol design mechanism makes it an open platform, bringing unlimited possibilities to developers.

In summary, AO's network architecture supports it to become a composable, interoperable, scalable, verifiable, decentralized and open computer network platform. It is not only suitable for social applications with the theme of information publishing and communication interaction, but also supports applications with higher computing performance requirements and more complex business logic, such as machine learning, autonomous decision-making agents, graphics rendering, online games and DeFi applications.

2. Nostr: Client-Relay Structure

Nostr is the abbreviation of "Notes and Other Stuff Transmitted by Relays", which means "Notes and other stuff transmitted by relays". There are two main components in the network, and its network structure is shown in Figure 1-2.

Figure 1-2 Nostr's network structure

  • Client

This is an application running on the user side that reads and writes data to the relay server. The client uses the public key as the address for the user to send and receive events, while the private key is used to sign when sending events to prove that it is the user's own operation and prevent tampering. When receiving events, the client uses the private key to verify the signature to confirm the source and integrity of the event.

The client allows users to connect to any number of relay servers distributed in different locations. Users can publish information on one relay and retrieve information on another relay. This means that the client (user) does not have to rely on any specific relay server, effectively protecting user data and behavior.

  • Relay

The relay server has the ability to listen to, capture and store events from clients connected to it, and forward these events to subscribed clients.

Anyone can run a relay server, and multiple relay servers can replace each other. This design weakens the importance of a single relay, reduces the risk of single point failure, and improves anti-censorship capabilities. In addition, competition between multiple relays can promote the improvement of service quality, such as providing larger storage capacity, faster response speed, and spam filtering services.

Relay servers can choose to store all or part of the user's content according to their own needs and decide the length of storage time, which provides greater flexibility for the positioning and business behavior of relays. At the same time, there is no need for relay servers to communicate with each other, so there is no consensus problem and no need for data synchronization. Data synchronization is achieved by sending and receiving events between clients, which is fundamentally different from blockchain nodes.

Such an architecture can not only improve the flexibility and efficiency of the system, but also effectively respond to different usage scenarios and needs.

It can be seen that Nostr uses a lightweight network structure such as Client-Relay, which can not only improve the flexibility and efficiency of the system, but also effectively support the construction of a decentralized, censorship-resistant, and verifiable information publishing system to meet people's needs for freedom of speech, smooth communication, and data security and privacy control. This design effectively responds to the challenges and drawbacks brought by centralized social media. Therefore, Nostr is known as a decentralized social protocol and is widely favored by developers for building various decentralized social applications, such as Damus, YakiHonne, Iris, etc.

3. Integration with other protocols

1. AO+Arweave: Decentralized World Computer

AO runs on top of Arweave and achieves seamless integration with Arweave, as shown in Figure 3-1.

Figure 3-1 AO and Arweave seamless integration (picture from AO white paper)

This is an implementation of the Storage Consensus Paradigm (SCP). In this innovative paradigm, storage (consensus) and computing are effectively separated, making off-chain computing and on-chain consensus possible. This architecture brings obvious advantages:

  • High-performance computing: Smart contract calculations are performed off-chain and are no longer subject to the on-chain block consensus process, which greatly expands computing performance and makes high-performance computing feasible.

  • Hyper-parallel computing: Each process on different nodes can independently perform parallel computing and local verification, without waiting for all nodes to complete repeated calculations and global consistency verification as in the traditional EVM architecture. This design enables AO to achieve hyper-parallel computing.

  • Customized computing: Arweave provides AO with permanent storage of all instructions, intermediate states, and computational results, serving as the data availability layer and consensus layer of AO. The execution of each application (smart contract) is closely related to the data stored in Arweave, and the computational logic and data resources can be customized according to the needs of the application to be executed on the local node. This flexibility far exceeds the traditional EVM model, where all nodes must execute predefined operations simultaneously to pursue the consistency of the entire network state.

In summary, AO adds a super-parallel computing layer to Arweave, while Arweave provides AO with storage-as-consensus support. The combination of the two creates a decentralized world computer, opening up a vast space for application innovation in the decentralized world.

2. Nostr + Lightning: Building a decentralized information and value network

Because Nostr's developer fiatjaf is also the developer of the Lightning Network, Nostr natively supports the Lightning Network. The Lightning Network is a second-layer solution for the Bitcoin blockchain that extends the functionality of the blockchain off-chain by using channels. It effectively solves the problems of slow Bitcoin transactions, limited throughput, and high transaction costs, making high-frequency, low-cost Bitcoin micropayments possible.

One of the most direct applications of the combination of Nostr and Lightning Network is to implement "lightning" in social applications. Nostr's popular client Damus has built-in Bitcoin Lightning Network payment function. Users only need to fill in Nostr's public key to easily call the Lightning Network to pay the one-time fee of Relay. After the payment is completed, the user will receive a Lightning Network invoice. For its detailed workflow, please refer to https://nostr.how/zh/zaps, which explains the operation steps in detail.

In terms of asset issuance, Taproot Assets (TAP), a Bitcoin layer asset issuance protocol, is compatible with the Lightning Network, which can introduce Taproot assets and Satoshis, the smallest unit of Bitcoin, into the Nostr ecosystem and use the Lightning Network for instant and affordable asset transfers. This not only enriches Nostr's asset types, but also provides more possibilities for application scenarios such as social networks, payments, and DeFi.

In addition, members of the CKB community also proposed the Nostr binding protocol, which uses RGB++ technology to isomorphically bind Nostr Event to CKB CELL. This move allows users to create and distribute native assets in the Nostr social network, effectively solving the native payment problem in social networks.

More importantly, the combination of Nostr and Lightning Network is opening up a new business model for decentralized applications, namely V4V (Value 4 Value).

The philosophy of V4V is that monetizing non-scarce information is a very difficult task. The default monetization model of the traditional online world usually relies on advertising, which is heavily dependent on centralized monitoring and user behavior analysis. V4V provides an alternative that allows the free flow of information and value without restrictions or intermediaries. This approach is not only a new way to monetize bits and bytes online, but also a new way to create content and transfer value.

V4V's solutions are bringing innovative value to social applications, podcasts, and live streaming platforms built on Nostr, such as:

  • YakIHONNE, a decentralized media information interaction protocol, supports the integration of Nostr and the Lightning Network, using SATS as reward payment, with a total payment of more than 90 million SATS throughout the year.

  • Nostrwatch.live is a decentralized live streaming platform running on Nostr and Lightning Network, building a "Value for Value" two-way streaming value exchange platform. When the broadcaster sends a live media stream to the audience, it also receives a SATs payment stream from the audience. Once the payment stops, the streaming signal will also stop playing. This is different from the traditional prepaid model, and the audience does not need to subscribe or pay in advance.

  • Podverse is a Podcasting 2.0 app that integrates with Alby, using the Lightning Network to send boostagrams (a donation method that sends messages to creators) and sat payment streams to podcasters. When “streaming Satoshis” in Podverse, the app sends Satoshis to the podcast the user is listening to for every minute of listening.

It can be seen that through the combination of Nostr and Lightning, Nostr has gradually evolved from a decentralized information transmission network to a decentralized transmission network that integrates information and value. This evolution can not only protect personal speech from infringement, but also ensure the security of personal assets, making it a carrier and network for value exchange. This evolution opens up new possibilities and development opportunities for innovation in large-scale and consumer-level applications, and may become a viable path to achieve large-scale adoption of Web3.

4. Summary: Structure determines function

In the above, we mainly compared and analyzed the AO and Nostr protocols from the two aspects of data structure and network structure, and based on the principle of "structure determines function", we deeply analyzed the main functions and application scenarios supported by each protocol:

  • From the data structure perspective

From the perspective of data structure, AO and Nostr protocols have some similarities. They are both information transmission protocols that support information publishing, communication interaction and content distribution of various data types, and can build decentralized social networks and decentralized social media applications. In addition, they both have the functional characteristics of decentralization, anti-censorship, signature verification, and privacy and security protection.

However, they also have significant differences. The positioning and main application scenarios of the Nostr protocol focus on the above-mentioned applications, and these are only a small subset of the functions and applications supported by the AO data structure. The focus of the AO protocol is to support ultra-parallel computing, and its application fields are broader and far-reaching.

  • From the perspective of network structure

From the perspective of network structure, the AO protocol has modular, cooperative and scalable network units, allowing processes to run independently on different nodes and perform local verification. These features provide the basic conditions for achieving super-parallel computing.

At the same time, the AO protocol breaks through the impossible triangle limitation of blockchain technology through seamless integration with Arweave based on the SCP paradigm. It can infinitely expand storage resources and computing resources according to demand, and use the consensus data with ownership protection permanently stored by Arweave to exchange information and collaborate between any processes (applications). Therefore, the AO protocol can build a high-performance, ultra-parallel computing network for the world, bringing innovation space to Web3 and even Web2 applications.

For example, it supports machine learning applications that require large language models (LLMs) and high-density computing; supports AgentFi that can meet complex business logic, predefined requirements and diversified autonomous strategies; supports copyright management and creator market (ContentFi) that emphasizes data ownership and content monetization; and supports decentralized applications that have data consensus requirements and require cross-chain information communication, cross-chain asset flow, cross-chain data sharing, and cross-chain interoperability of smart contracts.

In contrast, the Nostr protocol is mainly composed of two network components, Cliet-Relay, Event data structure, and public-private key system, which establishes a lightweight information publishing and receiving network. When the Nostr protocol is integrated with Lightning, the entire network combines the characteristics of decentralized information network and decentralized value network, which is more suitable for building large-scale, consumer-level application networks.

  • From the perspective of protocol positioning

From the perspective of protocol positioning, although AO and Nostr are both messaging protocols, their positioning and focus are different. The main focus of the AO protocol is to build infrastructure such as the "decentralized world computer", positioning the lower layer, but it opens up a broad space to support various applications, can capture a wider range of value, and bring the power of continuous upward development.

In contrast, the Nostr protocol was originally designed to support social applications and is positioned as a lightweight decentralized social protocol with more specific and focused application scenarios.

In summary, AO and Nostr have their own characteristics and advantages in data structure, network structure and protocol functions, and have different positioning and applicable scenarios. They will show their respective potential and value on different development paths.

References

  • AO Protocol: A decentralized, permissionless supercomputer

  • Nostr Protocol

  • Is AO the Ethereum killer? How will it promote the new narrative of blockchain?

  • Nostr Binding Agreement

  • Value4Value

  • Decentralized social protocol Nostr and its innovative applications