idnits 2.17.1 draft-xiong-rtgwg-precise-tn-requirements-00.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year == The document doesn't use any RFC 2119 keywords, yet seems to have RFC 2119 boilerplate text. -- The document date (April 24, 2020) is 1455 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) No issues found here. Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 RTGWG Q. Xiong 3 Internet-Draft ZTE Corporation 4 Intended status: Standards Track P. Liu 5 Expires: October 26, 2020 China Mobile 6 April 24, 2020 8 The Requirements for Precise Transport Networking 9 draft-xiong-rtgwg-precise-tn-requirements-00 11 Abstract 13 The future networks not only need to offer the Service Level 14 Agreements (SLA) guarantees such as low lantency and jitter, low 15 packet loss and high reliability, but also need to support the 16 precise services such as flexible resource allocation and service 17 isolation. This document proposes a set of performance requirements 18 and precise properties for Precise Transport Networking in various 19 industries such as 5G networks. 21 Status of This Memo 23 This Internet-Draft is submitted in full conformance with the 24 provisions of BCP 78 and BCP 79. 26 Internet-Drafts are working documents of the Internet Engineering 27 Task Force (IETF). Note that other groups may also distribute 28 working documents as Internet-Drafts. The list of current Internet- 29 Drafts is at https://datatracker.ietf.org/drafts/current/. 31 Internet-Drafts are draft documents valid for a maximum of six months 32 and may be updated, replaced, or obsoleted by other documents at any 33 time. It is inappropriate to use Internet-Drafts as reference 34 material or to cite them other than as "work in progress." 36 This Internet-Draft will expire on October 26, 2020. 38 Copyright Notice 40 Copyright (c) 2020 IETF Trust and the persons identified as the 41 document authors. All rights reserved. 43 This document is subject to BCP 78 and the IETF Trust's Legal 44 Provisions Relating to IETF Documents 45 (https://trustee.ietf.org/license-info) in effect on the date of 46 publication of this document. Please review these documents 47 carefully, as they describe your rights and restrictions with respect 48 to this document. Code Components extracted from this document must 49 include Simplified BSD License text as described in Section 4.e of 50 the Trust Legal Provisions and are provided without warranty as 51 described in the Simplified BSD License. 53 Table of Contents 55 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 56 2. Conventions used in this document . . . . . . . . . . . . . . 3 57 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 58 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 59 3. Terms of Precise Transport Networking . . . . . . . . . . . . 3 60 4. Requirements of Precise Transport Networking . . . . . . . . 4 61 4.1. Precise Latency, Jitter, and Packet Loss . . . . . . . . 4 62 4.2. Precise SLA Guarantees for Converged Networks . . . . . . 4 63 4.3. Precise Resource Allocation . . . . . . . . . . . . . . . 4 64 4.4. Precise Service Isolation . . . . . . . . . . . . . . . . 5 65 4.5. Precise OAM . . . . . . . . . . . . . . . . . . . . . . . 5 66 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 67 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5 68 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 69 8. Normative References . . . . . . . . . . . . . . . . . . . . 6 70 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 72 1. Introduction 74 5G network is oriented to the internet of everything. In addition to 75 the Enhanced Mobile Broadband (eMBB) and Massive Machine Type 76 Communications(mMTC) services, it also supports the Ultra-reliable 77 Low Latency Communications (uRLLC) services. The uRLLC services 78 cover the industries such as intelligent electrical network, 79 intelligent factory, internet of vehicles, industry automation and 80 other industrial internet scenarios, which is the key demand of 81 digital transformation of vertical domains. These uRLLC services 82 demand SLA guarantees such as low latency and high reliability and 83 other deterministic and precise properties. 85 For the intelligent electrical network, there are deterministic 86 requirements for communication delay, jitter and packet loss rate. 87 For example, in the electrical current difference model, a delay of 88 3~10ms and a jitter variation is no more than 100us are required. 89 The isolation requirement is also important. For example, the 90 automatic operation, control of a process, isochronous data and low 91 priority service need to meet the requirements of hard isolation. In 92 addition to the requirements of delay and jitter, the differential 93 protection (DP) service needs to be isolated from other services. 95 The industrial internet is the key infrastructure that coordinate 96 various units of work over various system components, e.g. people, 97 machines and things in the industrial environment including big data, 98 cloud computing, Internet of Things (IOT), Augment Reality (AR), 99 industrial robots, Artificial Intelligence (AI) and other basic 100 technologies. For example, automation control is one of the basic 101 application and the the core is closed-loop control system. The 102 control process cycle is as low as millisecond level, so the system 103 communication delay needs to reach millisecond level or even lower to 104 ensure the realization of precise control. There are three levels of 105 real-time requirements for industrial interconnection: factory level 106 is about 1s, and process level is 10~100ms, and the highest real-time 107 requirement is motion control, which requires less than 1ms. 109 The future networks not only need to offer the Service Level 110 Agreements (SLA) guarantees such as low latency and jitter, low 111 packet loss and high reliability, but also need to support the 112 precise services such as flexible resource allocation and service 113 isolation. This document proposes a set of performance requirements 114 and precise properties for Precise Transport Networking in various 115 industries such as 5G networks. 117 2. Conventions used in this document 119 2.1. Terminology 121 The terminology is defined as [RFC8655]. 123 2.2. Requirements Language 125 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 126 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 127 "OPTIONAL" in this document are to be interpreted as described in BCP 128 14 [RFC2119] [RFC8174] when, and only when, they appear in all 129 capitals, as shown here. 131 3. Terms of Precise Transport Networking 133 IEEE 802.1 Time-Sensitive Networking (TSN) has been proposed to 134 provide bounded latency and jitter in L2 LAN networks. According to 135 [RFC8655], Deterministic Networking (DetNet) operates at the IP layer 136 and delivers service with extremely low data loss rates and bounded 137 latency. 139 However, under the existing IP network architecture with statistical 140 multiplexing characteristics, the existing deterministic technologies 141 are facing long-distance transmission, queue scheduling, dynamic 142 flows and other controversial issues as described in [xiong-rtgwg- 143 precise-tn-problem-statement]. And besides precise latency, jitter, 144 and packet loss, more other precise and deterministic properties and 145 performances should be provided such as flexible resource allocation 146 and service isolation and so on. 148 Precise Transport Networking is defined to provide precise SLA 149 guarantees such as latency, jitter, packet loss rate, reliability, 150 and precise control such as flexible resource allocation and service 151 isolation and more other precise services intelligently and 152 dynamically. The purpose of the Precise Transport Networking is 153 based on the hierarchical structure of the transport network, taking 154 advantage of the existing technologies including the flexible precise 155 tunnels technology and the deterministic mechanisms, to support the 156 end-to-end precise service through the characteristics of slicing 157 pieces, hard isolation and preemption characteristics, so as to 158 achieve the high-precision of the future networks. 160 4. Requirements of Precise Transport Networking 162 4.1. Precise Latency, Jitter, and Packet Loss 164 It is required to provide precise Latency, jitter and packet loss 165 dynamically and flexibly in all scenarios for each characterizd flow. 167 The precise requirements of latency includes bounded latency and low 168 latency. The precise requirements of jitter includes bounded jitter 169 and low jitter. So the precise requirements of latency and jitter 170 may be the combination of latency and jitter, typically including 171 bounded latency and low jitter, low latency and bounded latency, and 172 so on. 174 4.2. Precise SLA Guarantees for Converged Networks 176 It is required to provide precise SLA guarantees for converged 177 networks including computing and network convergence, lossless and 178 network convergence, etc. 180 In some scenarios, such as MEC, it is required to provide precise 181 computing for Controlized CFN/APN. Other resources such as computing 182 resources, energy consumption should be considered. And the 183 utilization and optimization of network resources are extremely 184 important. 186 4.3. Precise Resource Allocation 188 As described in [RFC8655], the primary means by which DetNet achieves 189 its QoS assurances is to reduce, or even completely eliminate, packet 190 loss by the provision of sufficient buffer storage at each node. But 191 it can not be achieved by not sufficient resource which can be 192 allocated due to practical and cost reason. The existing solutions 193 can not achieve the precise resource allocation. 195 Precise resource allocation is required along with the explicit path 196 with more SLA guarantee parameters like bandwidth, latency, packet 197 loss and so on. The existing technologies such as FlexE and SR 198 tunnels should be taken into consideration. 200 4.4. Precise Service Isolation 202 It is required to provide precise service isolation for every flow. 203 In some scenarios, such as intelligent electrical network, the 204 isolation requirements are very important. For example, the 205 automatic operation or control of a process or isochronous data and 206 service with different priorities need to meet the requirements of 207 hard isolation. In addition to the requirements of delay and jitter, 208 the differential protection (DP) service needs to be isolated from 209 other services and hard isolated tunnel is required. 211 4.5. Precise OAM 213 It is required to consider precise service performance detection and 214 perception, service support and recovery mechanisms, such as 215 millisecond level service monitoring, 0.0001% packet loss awareness, 216 etc. The existing solutions also do not consider the statistics, 217 analysis and reporting of service performance. 219 Precise OAM is required including service monitoring, perception, 220 performance statistics, precise service support and recovery 221 mechanism, etc. The OAM mechanisms should be taken into 222 consideration such as In-band OAM, iOAM and so on. 224 5. Security Considerations 226 TBA 228 6. Acknowledgements 230 TBA 232 7. IANA Considerations 234 TBA 236 8. Normative References 238 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 239 Requirement Levels", BCP 14, RFC 2119, 240 DOI 10.17487/RFC2119, March 1997, 241 . 243 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 244 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 245 May 2017, . 247 [RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas, 248 "Deterministic Networking Architecture", RFC 8655, 249 DOI 10.17487/RFC8655, October 2019, 250 . 252 Authors' Addresses 254 Quan Xiong 255 ZTE Corporation 256 No.6 Huashi Park Rd 257 Wuhan, Hubei 430223 258 China 260 Email: xiong.quan@zte.com.cn 262 Peng Liu 263 China Mobile 264 Beijing 100053 265 China 267 Email: liupengyjy@chinamobile.com