Deterministic Networking Problem Statement
RFC 8557
Internet Engineering Task Force (IETF) N. Finn
Request for Comments: 8557 Huawei Technologies Co. Ltd
Category: Informational P. Thubert
ISSN: 2070-1721 Cisco
May 2019
Deterministic Networking Problem Statement
Abstract
This paper documents the needs in various industries to establish
multi-hop paths for characterized flows with deterministic
properties.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are candidates for any level of Internet
Standard; see Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8557.
Copyright Notice
Copyright (c) 2019 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
(https://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 Simplified BSD License.
Finn & Thubert Informational [Page 1]
RFC 8557 Deterministic Networking Problem Statement May 2019
Table of Contents
1. Introduction ....................................................2
2. On Deterministic Networking .....................................4
3. Problem Statement ...............................................6
3.1. Supported Topologies .......................................6
3.2. Flow Characterization ......................................6
3.3. Centralized Path Computation and Installation ..............7
3.4. Distributed Path Setup .....................................8
3.5. Duplicated Data Format .....................................8
4. Security Considerations .........................................9
5. IANA Considerations .............................................9
6. Informative References .........................................10
Acknowledgments ...................................................11
Authors' Addresses ................................................11
1. Introduction
"Deterministic Networking Use Cases" [RFC8578] illustrates that
beyond the classical case of Industrial Automation and Control
Systems (IACSs) there are in fact multiple industries with strong,
and relatively similar, needs for deterministic network services with
latency guarantees and ultra-low packet loss.
The generalization of the needs for more deterministic networks has
led to the IEEE 802.1 Audio Video Bridging (AVB) Task Group becoming
the Time-Sensitive Networking (TSN) [IEEE-802.1TSNTG] Task Group
(TG), with a much-expanded constituency from the industrial and
vehicular markets.
Along with this expansion, the networks considered here are becoming
larger and structured, requiring deterministic forwarding beyond the
LAN boundaries. For instance, an IACS segregates the network along
the broad lines of the Purdue Enterprise Reference Architecture
(PERA) [ISA95], typically using deterministic LANs for Purdue level 2
control systems, whereas public infrastructures such as electricity
automation require deterministic properties over the wide area.
Implementers have come to realize that the convergence of IT and
Operation Technology (OT) networks requires Layer 3, as well as
Layer 2, capabilities.
While the initial user base has focused almost entirely on Ethernet
physical media and Ethernet-based bridging protocols from several
Standards Development Organizations (SDOs), the need for Layer 3, as
expressed above, must not be confined to Ethernet and Ethernet-like
media. While such media must be encompassed by any useful
Deterministic Networking (DetNet) architecture, cooperation between
the IETF and other SDOs must not be limited to the IEEE or the
Finn & Thubert Informational [Page 2]
RFC 8557 Deterministic Networking Problem Statement May 2019
Show full document text