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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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Mandrake: multiagent systems as a basis for programming fault-tolerant decentralized applications
Abstract We conceptualize adecentralizedsoftware application as one constituted fromautonomousagents that communicate viaasynchronousmessaging. Modern software paradigms such as microservices and settings such as the Internet of Things evidence a growing interest in decentralized applications. Constructing a decentralized application involves designing agents as independent local computations that coordinate successfully to realize the application’s requirements. Moreover, a decentralized application is susceptible to faults manifested as message loss, delay, and reordering. We contributeMandrake, a programming model for decentralized applications that tackles these challenges without relying on infrastructure guarantees. Specifically, we adopt the construct of aninformation protocolthat 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 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. Mandrake’s significance lies in demonstrating a straightforward approach for constructing decentralized applications without relying on coordination mechanisms in the infrastructure, thus achieving some of the goals of the founders of networked computing from the 1970s.
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- Award ID(s):
- 1908374
- PAR ID:
- 10366555
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Autonomous Agents and Multi-Agent Systems
- Volume:
- 36
- Issue:
- 1
- ISSN:
- 1387-2532
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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