Network Working Group C. Pignataro Internet-Draft J. Parikh Intended status: Experimental NC State University Expires: 5 September 2024 R. Bonica Juniper M. Welzl University of Oslo 4 March 2024 ICMP Extensions for Environmental Information draft-pignataro-eimpact-icmp-01 Abstract This document defines a data structure that can be appended to selected ICMP messages. The ICMP extension defined herein can be used to gain visibility on environmental impact information on the Internet by providing per-hop (i.e., per topological network node) power metrics and other current or future sustainability metrics. This will contribute to achieving an objective mentioned in the IAB E-Impact workshop. The techniques presented are useful not only in a transactional setting (e.g., a user-issued traceroute or a ping request), but also in a scheduled automated setting where they may be run periodically in a mesh across an administrative domain to map out environmental- impact metrics. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 5 September 2024. Pignataro, et al. Expires 5 September 2024 [Page 1] Internet-Draft ICMP E-Impact Extensions March 2024 Copyright Notice Copyright (c) 2024 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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Definition of Terms . . . . . . . . . . . . . . . . . . . 3 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 3. Application . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Transport Options for Sustainability Information . . . . . . 4 5. ICMP Environmental Information Extension . . . . . . . . . . 4 5.1. Extension Format . . . . . . . . . . . . . . . . . . . . 5 5.2. C-Type Definition . . . . . . . . . . . . . . . . . . . . 6 6. Sample Use Case . . . . . . . . . . . . . . . . . . . . . . . 8 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 10.1. Normative References . . . . . . . . . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 1. Introduction IP devices use the Internet Control Message Protocol ICMPv4 [RFC0792] and ICMPv6 [RFC4443] to convey control information to source hosts. In particular, when an IP device receives a datagram that it cannot process, it may send an ICMP message to the datagram's originator or source. Network operators and higher-level protocols use these ICMP messages to detect and diagnose network issues. As the world transitions towards sustainability in technology, the focus is shifting not only on creating modern technologies infused with sustainability but also on bridging gaps in the tools that are already available, to enhance visibility, measurement, and quantification of their impact. Consequently, tools which have been Pignataro, et al. Expires 5 September 2024 [Page 2] Internet-Draft ICMP E-Impact Extensions March 2024 foundational for control and management for decades now encounter new requirements including enhancing them to cater to a significantly increasing demand for monitoring the sustainability and environmental impact. This document serves that need by defining an ICMP extension object that appends environmental impact information to ICMP messages. Using the extension defined herein, a device can explicitly append these exemplary environmental impact metrics for transmission across an administrative domain: * Power metrics (e.g., time average, min/max) * Electrical Energy Provider or Zone * Geolocation * Future sustainability metrics 2. Conventions 2.1. Definition of Terms This document uses the following terms: ICMP: Generically referring to ICMPv4 [RFC0792] and ICMPv6 [RFC4443] messages. ICMP Extension: Extended ICMP to support multi-part messages through an ICMP extension structure, as defined in [RFC4884]. 2.2. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Application The IAB held a workshop on "Environmental Impact of Internet Applications and Systems (eimpactws)" [IAB-EIMPACTWS], in which the need for visibility into environmental impact metrics within traditional Internet tools such as traceroute was highlighted (see WebVTT cue identifiers 139 and 140 of [IAB-EIMPACTWS-Minutes].) Pignataro, et al. Expires 5 September 2024 [Page 3] Internet-Draft ICMP E-Impact Extensions March 2024 The Environmental Information ICMP Extensions defined in this document allow for augmenting the traceroute output with environmental metrics from each reported node. 4. Transport Options for Sustainability Information To achieve the goal of transporting useful sustainability information across the network, there are two key considerations. First, what information is useful to convey and in what format, and second, how to transport that sustainability information. For the first task, it is critical to normalize and agree upon the information to convey and format, across potentially multiple transports. For the second task, there is a variety of options available depending on use cases. These can be categorized based on whether the approach is distributed (i.e., any endpoint or node can request and/or receive the sustainability information) or centralized (i.e., a single 'controller' compiles and consolidates the information.) They can also be categorized based on the networking layer used (e.g., IP, like ICMP, or application, like SNMP). Further, an existing protocol can be extended, or a brand new protocol can potentially be created for this purpose. This document builds upon a standardized, modular, backwards- compatible, and scale-proven ICMP extension [RFC4884]. This does not preclude the definition of other methods to transport sustainability information, more fitting to other use-cases. 5. ICMP Environmental Information Extension This section defines the Environmental Information Object, an ICMP extension object with a Class-Num (Object Class Value) of TBA that can be appended to the following messages, as per [RFC4884] and [RFC8335]: * ICMPv4 Time Exceeded * ICMPv4 Destination Unreachable * ICMPv4 Parameter Problem * ICMPv4 Extended Echo Reply [RFC8335] * ICMPv6 Time Exceeded * ICMPv6 Destination Unreachable * ICMPv6 Extended Echo Reply [RFC8335] The ICMP extension defined in this document MAY be appended to any of the above listed messages based on policy and following security considerations. Pignataro, et al. Expires 5 September 2024 [Page 4] Internet-Draft ICMP E-Impact Extensions March 2024 These extensions are preceded by an ICMP Extension Structure Header, and include an ICMP Object Header. Both are defined in [RFC4884]. The same backward compatibility issues that apply to [RFC4884] apply to this extension. A single ICMP message can contain zero, one, or multiple instances of Environmental Information Objects. The C-Type further identifies the information fields carried. A single instance of the Environmental Information Object can convey one of the information elements defined in Section 5.2 from each reporting node in an administrative domain. 5.1. Extension Format The ICMP Environmental Information Extension has the following format. 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+... |Version| Reserved | Checksum |(1) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+... | Length | Class-Num | C-Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+(2) ~ Object payload ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+... Figure 1: ICMP Environmental Information Extension Format (1) ICMP Extension Header Version: 2 [RFC4884]. Reserved: 0 [RFC4884]. Checksum: The one's complement checksum of the ICMP extension [RFC4884]. (2) Environmental Information Object Length: Length of the object, including header and payload, in octets. Class-Num: TBA (Environmental Information) Pignataro, et al. Expires 5 September 2024 [Page 5] Internet-Draft ICMP E-Impact Extensions March 2024 C-Type: C-Type as explained in Section 5.2. Object Payload: As defined by each C-Type. While there is a single ICMP Extension Header, there could be multiple Environmental Information Objects. 5.2. C-Type Definition The 8-bit C-Type defined in the Section 8 of [RFC4884] allows to carry different information elements within this Class-Num (TBA). The techniques herein defined can be used with any specific e-impact metric in use, current or future. The ICMP Environmental Information Extension Object header has the following format: 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Class-Num=TBA | C-Type=1-255 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: Environmental Information Extension Object Header The following C-Type values are currently defined. 1. Node Power Draw Sub-Object 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Power (32-bit unsigned word) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: Node Power Draw Sub-Object A Class-Num of TBA and a C-Type of 1 are specified. The Length is always 8. The returned value is the node-level current power being drawn, which is a magnitude that may be directly displayed, and is expressed in Watts (W). 2. Node Throughput Sub-Object Pignataro, et al. Expires 5 September 2024 [Page 6] Internet-Draft ICMP E-Impact Extensions March 2024 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Throughput (32-bit unsigned word) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: Node Throughput Sub-Object A Class-Num of TBA and a C-Type of 2 are specified. The Length is always 8. The returned value is the node-level current throughput, which is a magnitude that may be directly displayed, and is expressed in bits-per-second (BPS). This allows the recipient of the ICMP message to determine a relationship between power and traffic load. 3. Ecolabels and Environmentally Relevant Certification (EERC) Sub- Object 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | EERC number |0 0 0 0| Year | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: EERC Sub-Object A Class-Num of TBA and a C-Type of 3 are specified. The Length is always 8. The returned value references an Ecolabels and Environmentally Relevant Certification (EERC) number. The following EERC numbers are defined by the present specification: 1. ISO 14001:2015 2. TCO Certified 3. Energy-efficient ethernet The "Year" field must contain the year in which the certificate was issued, or 0 to indicate "unknown" or "not specified". 4. Component-level Power Draw Sub-Object Pignataro, et al. Expires 5 September 2024 [Page 7] Internet-Draft ICMP E-Impact Extensions March 2024 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | UUID 32-bit Word 1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | UUID 32-bit Word 2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | UUID 32-bit Word 3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | UUID 32-bit Word 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Component Power (32-bit word) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 6: Component-level Power Draw Element A Class-Num of TBA and a C-Type of 4 are specified. The Length is always 4 plus 20 times the number of elements included. The returned value is one or more instances of component-level power drawn metrics. Each instance is a set comprised by a UUID uniquely indentifying the component, and the actual power being drawn by said component expressed in Watts (W). 6. Sample Use Case This section explains a typical use case of the extensions. 7. Security Considerations The security considerations of [RFC4884] and of [RFC8335] apply to these extensions. Upon receipt of an ICMP message, application software must check it for syntactic correctness. The extension checksum MUST be verified. Care should be taken, as improperly specified length attributes and other syntax problems may result in buffer overruns. This document does not define the conditions under which a router sends an ICMP message. Therefore, it does not expose routers to any new denial-of-service attacks. Routers may need to limit the rate at which ICMP messages are sent. Pignataro, et al. Expires 5 September 2024 [Page 8] Internet-Draft ICMP E-Impact Extensions March 2024 This document defines an extension that allows a router to append environmental impact information to multi-part ICMP messages in a single administrative domain, and therefore can provide the user of the traceroute and ping applications with additional metrics. The intended field of use for the extensions defined in this document is administrative debugging and troubleshooting and operational facilities. The extensions herein defined supply additional information in ICMP responses. These mechanisms are not initially intended for other uses. Some of the additional metrics provided, as e.g., power draw information, have privacy considerations. For example, behavioral considerations of the devices, or estimating other node and network attributes from the power or energy data. Other things like identification of the node, deducing node usage patterns are some more privacy concerns that can be related to the metrics. Keeping these considerations in mind, we limited the scope of the transportation of the sustainability metrics to a single administrative domain. But, based on [RFC8799], limiting a protocols functionality doesn't mean that it will be secure. So, this particular document, which defines "a modified ICMP message with sustainability metrics", can be classified as a FAIL-OPEN protocol [I-D.wkumari-intarea-safe-limited-domains]. That is, the interfaces of administrative domain border nodes, facing towards the open internet, can be configured such that they avoid leaking messages with extensions containing sustainability metrics, out of the AD. To allow general ICMP messages, an administrator can configure those outward facing interfaces to not block/drop the entire message but only strip off the extension objects and only forward the ICMP message if it is destined to go out of the AD. When metrics are limited to the same AD, it can be considered that they can be generated from a valid source and will have integrity. This document does not specify an authentication mechanism for the extension that it defines. Application developers should be aware of various ICMP attacks [RFC5927]. 8. IANA Considerations IANA is requested to assign the following object Class-num in the ICMP Extension Object Classes and Class Sub-types registry [IANA-ICMP-Extended]: Pignataro, et al. Expires 5 September 2024 [Page 9] Internet-Draft ICMP E-Impact Extensions March 2024 +=============+==================================+===============+ | Class Value | Class name | Reference | +=============+==================================+===============+ | TBA | Environmental Information Object | This document | +-------------+----------------------------------+---------------+ Table 1: Class-num for Environmental Information Extensions IANA is requested to establish a registry for the corresponding class sub-type (C-Type) space, as follows: +==============+===============================+===============+ | C-Type Value | Description | Reference | +==============+===============================+===============+ | 0 | Reserved | This document | +--------------+-------------------------------+---------------+ | 1 | Node Power Draw | This document | +--------------+-------------------------------+---------------+ | 2 | Node Throughput | This document | +--------------+-------------------------------+---------------+ | 3 | Ecolabels and Environmentally | This document | | | Relevant Certification (EERC) | | +--------------+-------------------------------+---------------+ | 4 | Component-level Power Draw | This document | +--------------+-------------------------------+---------------+ | 2-246 | Unassigned | | +--------------+-------------------------------+---------------+ | 247-255 | Reserved for Experimentation | This document | +--------------+-------------------------------+---------------+ Table 2: C-Types for Environmental Information Extensions C-Type values are assignable on a first-come-first-serve (FCFS) basis. IANA is requested to establish a registry for Ecolabels and Environmentally Relevant Certification (EERC) numbers (C-Type 2), as follows: Pignataro, et al. Expires 5 September 2024 [Page 10] Internet-Draft ICMP E-Impact Extensions March 2024 +=============+==============================+===============+ | Number | Name | Reference | +=============+==============================+===============+ | 0 | Reserved | | +-------------+------------------------------+---------------+ | 1 | ISO 14001:2015 | This document | +-------------+------------------------------+---------------+ | 2 | TCO Certified | This document | +-------------+------------------------------+---------------+ | 3 | Energy-efficient ethernet | This document | +-------------+------------------------------+---------------+ | 4-65527 | Unassigned | | +-------------+------------------------------+---------------+ | 65528-65535 | Reserved for Experimentation | This document | +-------------+------------------------------+---------------+ Table 3: EERC numbers EERC numbers are assignable on a first-come-first-serve (FCFS) basis. 9. Acknowledgements We are very grateful to Jari Arkko for his thorough review and most useful set of comments and suggestions. 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC4884] Bonica, R., Gan, D., Tappan, D., and C. Pignataro, "Extended ICMP to Support Multi-Part Messages", RFC 4884, DOI 10.17487/RFC4884, April 2007, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8335] Bonica, R., Thomas, R., Linkova, J., Lenart, C., and M. Boucadair, "PROBE: A Utility for Probing Interfaces", RFC 8335, DOI 10.17487/RFC8335, February 2018, . Pignataro, et al. Expires 5 September 2024 [Page 11] Internet-Draft ICMP E-Impact Extensions March 2024 10.2. Informative References [I-D.wkumari-intarea-safe-limited-domains] Kumari, W. A., Alston, A., Vyncke, E., and S. Krishnan, "Safe(r) Limited Domains", Work in Progress, Internet- Draft, draft-wkumari-intarea-safe-limited-domains-00, 19 January 2024, . [IAB-EIMPACTWS] "IAB workshop on Environmental Impact of Internet Applications and Systems (eimpactws)", December 2022, . [IAB-EIMPACTWS-Minutes] "Minutes for the IAB E-Impact Workshop Session 4: Next Steps", eimpactws Session 4, 12 December 2022, . [IANA-ICMP-Extended] "Internet Control Message Protocol (ICMP) Parameters, ICMP Extension Object Classes and Class Sub-types", . [RFC0792] Postel, J., "Internet Control Message Protocol", STD 5, RFC 792, DOI 10.17487/RFC0792, September 1981, . [RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification", STD 89, RFC 4443, DOI 10.17487/RFC4443, March 2006, . [RFC5927] Gont, F., "ICMP Attacks against TCP", RFC 5927, DOI 10.17487/RFC5927, July 2010, . [RFC8799] Carpenter, B. and B. Liu, "Limited Domains and Internet Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020, . Authors' Addresses Pignataro, et al. Expires 5 September 2024 [Page 12] Internet-Draft ICMP E-Impact Extensions March 2024 Carlos Pignataro North Carolina State University United States of America Email: cpignata@gmail.com, cmpignat@ncsu.edu Jainam Parikh North Carolina State University United States of America Email: jainam@parikhgroup.net, jparikh@ncsu.edu Ron Bonica Juniper Networks United States of America Email: rbonica@juniper.net Michael Welzl University of Oslo Norway Email: michawe@ifi.uio.no Pignataro, et al. Expires 5 September 2024 [Page 13]