We define a decentralized software application as one that consists of autonomous agents that communicate through asynchronous messaging. Constructing a decentralized application involves designing agents as independent local computations that coordinate to realize the application’s requirements. Moreover, a decentralized application is susceptible to faults manifested as message loss, delay, and reordering. We contribute Mandrake, a programming model for decentralized applications that addresses these challenges. Specifically, we adopt the construct of an information protocol that specifies messaging between agents purely in causal terms and can be correctly enacted by agents in a shared-nothing environment over nothing more than unreliable, unordered transport. Mandrake facilitates (1) implementing protocol-compliant agents by introducing a programming model; (2) transforming fragile protocols into fault-tolerant ones with simple annotations; and (3) a declarative policy language that makes it easy to implement fault-tolerance in agents based on the capabilities in protocols. In obviating the reliance on reliability and ordering guarantees in the communication infrastructure, Mandrake achieves some of the goals of the founders of networked computing from the 1970s.
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Deserv: Decentralized Serverless Computing
A decentralized application involves multiple autonomous principals, e.g., humans and organizations. Autonomy motivates (1) specifying a decentralized application via a protocol that captures the interactions between the principals, and (2) a programming model that enables each principal to independently (from other principals) construct its own protocol-compliant agent. An agent encodes its principal's decision making and represents it in the application. We contribute Deserv, the first protocol-based programming model for decentralized applications that is suited to the cloud. Specifically, Deserv demonstrates how to leverage function-as-a-service (FaaS), a popular serverless programming model, to implement agents. A notable feature of Deserv is the use declarative protocols to specify interactions. Declarative protocols support implementing stateful agents in a manner that naturally exploits the concurrency and autoscaling benefits offered by serverless computing.
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- Award ID(s):
- 1908374
- PAR ID:
- 10293725
- Date Published:
- Journal Name:
- Proceedings of the 19th IEEE International Conference on Web Services
- Page Range / eLocation ID:
- 1-10
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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