Application-Layer Traffic Optimization (ALTO) Problem Statement
RFC 5693
Document | Type | RFC - Informational (October 2009; No errata) | |
---|---|---|---|
Authors | Jan Seedorf , Eric Burger | ||
Last updated | 2018-12-20 | ||
Replaces | draft-marocco-alto-problem-statement | ||
Stream | Internent Engineering Task Force (IETF) | ||
Formats | plain text html pdf htmlized (tools) htmlized bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5693 (Informational) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Lisa Dusseault | ||
Send notices to | jon.peterson@neustar.biz |
Network Working Group J. Seedorf Request for Comments: 5693 NEC Category: Informational E. Burger Neustar Inc. October 2009 Application-Layer Traffic Optimization (ALTO) Problem Statement Abstract Distributed applications -- such as file sharing, real-time communication, and live and on-demand media streaming -- prevalent on the Internet use a significant amount of network resources. Such applications often transfer large amounts of data through connections established between nodes distributed across the Internet with little knowledge of the underlying network topology. Some applications are so designed that they choose a random subset of peers from a larger set with which to exchange data. Absent any topology information guiding such choices, or acting on suboptimal or local information obtained from measurements and statistics, these applications often make less than desirable choices. This document discusses issues related to an information-sharing service that enables applications to perform better-than-random peer selection. Status of This Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the BSD License. Seedorf & Burger Informational [Page 1] RFC 5693 ALTO Problem Statement October 2009 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. State-of-the-Art . . . . . . . . . . . . . . . . . . . . . 4 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. The Problem . . . . . . . . . . . . . . . . . . . . . . . . . 7 4. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1. File sharing . . . . . . . . . . . . . . . . . . . . . . . 8 4.2. Cache/Mirror Selection . . . . . . . . . . . . . . . . . . 8 4.3. Live Media Streaming . . . . . . . . . . . . . . . . . . . 8 4.4. Real-Time Communications . . . . . . . . . . . . . . . . . 9 4.5. Distributed Hash Tables . . . . . . . . . . . . . . . . . 9 5. Aspects of the Problem . . . . . . . . . . . . . . . . . . . . 9 5.1. Information Provided by an ALTO Service . . . . . . . . . 9 5.2. ALTO Service Providers . . . . . . . . . . . . . . . . . . 10 5.3. ALTO Service Implementation . . . . . . . . . . . . . . . 10 5.4. User Privacy . . . . . . . . . . . . . . . . . . . . . . . 10 5.5. Topology Hiding . . . . . . . . . . . . . . . . . . . . . 11 5.6. Coexistence with Caching . . . . . . . . . . . . . . . . . 11 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 12 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12 9. Informative References . . . . . . . . . . . . . . . . . . . . 13 1. Introduction 1.1. Overview Distributed applications, both peer-to-peer (P2P) and client/server used for file sharing, real-time communication, and live and on- demand media streaming, use a significant amount of network capacity and CPU cycles in the routers [WWW.wired.fuel]. In contrast to centralized applications, distributed applications access resources such as files or media relays distributed across the Internet and exchange large amounts of data in connections that they establish directly with nodes sharing such resources. One advantage of highly distributed systems results from the fact that the resources such systems offer are often available through multiple replicas. However, applications generally do not have reliable information of the underlying network and thus have to select among the available peers that provide such replicas randomly or based on information they deduce from partial observations that, in some situations, lead to suboptimal choices. For example, oneShow full document text