RFC 8305 · PROPOSED STANDARD · 2017

Happy Eyeballs Version 2: Better Connectivity Using Concurrency

Overview

RFC 8305, “Happy Eyeballs Version 2: Better Connectivity Using Concurrency”, is a Proposed Standard document published in December 2017 by D. Schinazi, T. Pauly. It obsoletes RFC 6555. The canonical text is published by the RFC Editor.

Abstract

Many communication protocols operating over the modern Internet use hostnames. These often resolve to multiple IP addresses, each of which may have different performance and connectivity characteristics. Since specific addresses or address families (IPv4 or IPv6) may be blocked, broken, or sub-optimal on a network, clients that attempt multiple connections in parallel have a chance of establishing a connection more quickly. This document specifies requirements for algorithms that reduce this user-visible delay and provides an example algorithm, referred to as "Happy Eyeballs". This document obsoletes the original algorithm description in RFC 6555.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 8305 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 6555
Other RFCs from 2017

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