[alto] RFC 9439 on Application-Layer Traffic Optimization (ALTO) Performance Cost Metrics

rfc-editor@rfc-editor.org Sat, 12 August 2023 04:53 UTC

Return-Path: <wwwrun@rfcpa.amsl.com>
X-Original-To: alto@ietfa.amsl.com
Delivered-To: alto@ietfa.amsl.com
Received: from localhost (localhost []) by ietfa.amsl.com (Postfix) with ESMTP id A3263C1CAB29; Fri, 11 Aug 2023 21:53:07 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: 0.533
X-Spam-Status: No, score=0.533 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, RDNS_NONE=0.793, SPF_HELO_SOFTFAIL=0.732, SPF_SOFTFAIL=0.665, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=no autolearn_force=no
Received: from mail.ietf.org ([]) by localhost (ietfa.amsl.com []) (amavisd-new, port 10024) with ESMTP id dGjamwWVcitT; Fri, 11 Aug 2023 21:53:03 -0700 (PDT)
Received: from rfcpa.amsl.com (unknown []) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 5B366C374845; Fri, 11 Aug 2023 21:52:16 -0700 (PDT)
Received: by rfcpa.amsl.com (Postfix, from userid 499) id 463CEE7122; Fri, 11 Aug 2023 21:52:16 -0700 (PDT)
To: ietf-announce@ietf.org, rfc-dist@rfc-editor.org
From: rfc-editor@rfc-editor.org
Cc: rfc-editor@rfc-editor.org, drafts-update-ref@iana.org, alto@ietf.org
Content-type: text/plain; charset="UTF-8"
Message-Id: <20230812045216.463CEE7122@rfcpa.amsl.com>
Date: Fri, 11 Aug 2023 21:52:16 -0700
Archived-At: <https://mailarchive.ietf.org/arch/msg/alto/ngvbSd1dZ3RvEEvK6PhdCwBmtMw>
Subject: [alto] RFC 9439 on Application-Layer Traffic Optimization (ALTO) Performance Cost Metrics
X-BeenThere: alto@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: "Application-Layer Traffic Optimization \(alto\) WG mailing list" <alto.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/alto>, <mailto:alto-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/alto/>
List-Post: <mailto:alto@ietf.org>
List-Help: <mailto:alto-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/alto>, <mailto:alto-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 12 Aug 2023 04:53:07 -0000

A new Request for Comments is now available in online RFC libraries.

        RFC 9439

        Title:      Application-Layer Traffic Optimization (ALTO) 
                    Performance Cost Metrics 
        Author:     Q. Wu,
                    Y. Yang,
                    Y. Lee,
                    D. Dhody,
                    S. Randriamasy,
                    L. Contreras
        Status:     Standards Track
        Stream:     IETF
        Date:       August 2023
        Mailbox:    bill.wu@huawei.com,
        Pages:      35
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-ietf-alto-performance-metrics-28.txt

        URL:        https://www.rfc-editor.org/info/rfc9439

        DOI:        10.17487/RFC9439

The cost metric is a basic concept in Application-Layer Traffic
Optimization (ALTO), and different applications may use different
types of cost metrics. Since the ALTO base protocol (RFC 7285)
defines only a single cost metric (namely, the generic "routingcost"
metric), if an application wants to issue a cost map or an endpoint
cost request in order to identify a resource provider that offers
better performance metrics (e.g., lower delay or loss rate), the base
protocol does not define the cost metric to be used.

This document addresses this issue by extending the specification to
provide a variety of network performance metrics, including network
delay, delay variation (a.k.a. jitter), packet loss rate, hop count,
and bandwidth.

There are multiple sources (e.g., estimations based on measurements
or a Service Level Agreement) available for deriving a performance
metric. This document introduces an additional "cost-context" field
to the ALTO "cost-type" field to convey the source of a performance

This document is a product of the Application-Layer Traffic Optimization Working Group of the IETF.

This is now a Proposed Standard.

STANDARDS TRACK: This document specifies an Internet Standards Track
protocol for the Internet community, and requests discussion and suggestions
for improvements.  Please refer to the current edition of the Official
Internet Protocol Standards (https://www.rfc-editor.org/standards) for the 
standardization state and status of this protocol.  Distribution of this 
memo is unlimited.

This announcement is sent to the IETF-Announce and rfc-dist lists.
To subscribe or unsubscribe, see

For searching the RFC series, see https://www.rfc-editor.org/search
For downloading RFCs, see https://www.rfc-editor.org/retrieve/bulk

Requests for special distribution should be addressed to either the
author of the RFC in question, or to rfc-editor@rfc-editor.org.  Unless
specifically noted otherwise on the RFC itself, all RFCs are for
unlimited distribution.

The RFC Editor Team
Association Management Solutions, LLC