| Internet-Draft | Available Session Recovery Protocol | October 2026 |
| Luo & Yan | Expires 24 April 2027 | [Page] |
This document describes an experimental protocol, the Available Session Recovery Protocol (ASRP), for high-availability clusters that provide stateful network services - load balancing, Network Address Translation (NAT [RFC4787]), and other layer-4 stateful network functions, including their virtualized (NFV) forms. ASRP backs up the session state at the session's own endpoints, so that the cluster nodes hold no replicated state: no inter-node synchronization, no backup node, and no state warm-up for a newly added node. The document defines the procedures and message formats for session backup and recovery.¶
In contrast to traditional high-availability techniques that back up session state within the cluster itself, the core innovation of ASRP lies in its distributed backup of state information to the client or server side. This approach offers multiple advantages: theoretically unlimited elastic scaling capacity; support for rapid recovery from multi-point failures; reduction of resource redundancy through the elimination of centralized backup nodes; and significant simplification of cluster implementation complexity.¶
The ASRP protocol provides a standardized method for constructing elastic service clusters, facilitating broader participation from software and hardware developers in building elastic cloud network service clusters.¶
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