RFC 4095 · PROPOSED STANDARD · 2005

Attaching Meaning to Solicitation Class Keywords

Overview

RFC 4095, “Attaching Meaning to Solicitation Class Keywords”, is a Proposed Standard document published in May 2005 by C. Malamud. The canonical text is published by the RFC Editor.

Abstract

This document proposes a mechanism for finding a URI associated with a solicitation class keyword, which is defined in RFC 3865, the No Soliciting SMTP Service Extension. Solicitation class keywords are simple labels consisting of a domain name that has been reversed, such as "org.example.adv". These solicitation class keywords are inserted in selected header fields or used in the ESMTP service extension, including a new \%"No-Solicit:" header, which can contain one or more solicitation class keywords inserted by the sender.

This document specifies an application based on the Dynamic Delegation Discovery System (DDDS) described in RFC 3401 and related documents. An algorithm is specified to associate a solicitation class keyword with a URI which contains further information about the meaning and usage of that solicitation class keyword. For example, the registrant of the "example.org" domain could use this mechanism to create a URI which contains detailed information about the "org.example.adv" solicitation class keyword. [STANDARDS-TRACK]

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 4095 is hosted at rfc-editor.org. Available in TXT,HTML.

Other RFCs from 2005

Who Is Online

In total there are 301 users online: 0 registered, 296 guests and 5 bots.

Most users ever online was 1,226 on 13 Jun 2026, 3:56 am.

Bots: Applebot Facebook Other Bot Other Crawler SemrushBot

Users active in the past 15 minutes. Total registered members: 354