Network Working Group G. Fioccola Internet-Draft Huawei Technologies Intended status: Informational P. Mendes Expires: 11 January 2024 Airbus J. Burke UCLA REMAP D. Kutscher HKUST(GZ) 10 July 2023 Metaverse impacts on the Internet technologies draft-fmbk-icnrg-metaverse-00 Abstract This document aims to explore the new challenges for the transport network brought by the development of Metaverse. It discusses the Metaverse as an Information-Centric Network (ICN). 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 11 January 2024. Copyright Notice Copyright (c) 2023 IETF Trust and the persons identified as the document authors. All rights reserved. Fioccola, et al. Expires 11 January 2024 [Page 1] Internet-Draft Metaverse July 2023 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. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Gap Analysis . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Solution with an ICN approach . . . . . . . . . . . . . . . . 5 4.1. Technical challenges . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 6 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 6 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 9. Informative References . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction The Web today essentially represents a data-centric application layer: data named by URLs is manipulated with Representational State Transfer (REST) primitives. However, the semantic gap with the underlying host-oriented transport is significant. The interest in “the Metaverse” suggests that the end-user experience of the Web will evolve towards an always-on eXtended Reality (XR). Metaverse introduces the concept of a persistent virtual space of everyday life as platform-agnostic digital space. It is an interconnected and limitless virtual world populated by an extension of physical identities, a digital twin of the physical world. Metaverse can be seen as the 3D generation of the Internet accessible via new non-intrusive interfaces (e.g. holographics) and making use of new types of information (e.g. haptic, temperature, smell, emotions, digital transactions) that can be exchanged between people, simulated users, and cyber-physical systems, while preserving data privacy. Fioccola, et al. Expires 11 January 2024 [Page 2] Internet-Draft Metaverse July 2023 Metaverse can also be seen as the next generation of Internet, that can be built based on Web 3.0. The Web 3.0 is an idea for a new iteration of the World Wide Web which incorporates concepts such as decentralization, trustworthy interactions, peer-to-peer, data distribution, decentralized identifiers. This is something more and different from the vision of Metaverse as full Virtual Reality (VR) and Augmented Reality (AR). For this reason, the Metaverse should be considered not as an application of the current network, but an evolution of the network itself, reducing rather than widening the gap between network architecture and application semantics. The ICN architecture is discussed in this document since it allows to achieve the integration of application and network layers with less overhead, low latency, better security, and more disruption tolerance suitable to diverse uses cases. 2. Requirements [I-D.han-iccrg-arvr-transport-problem] started to analyze the requirements of VR and AR to networking, especially to transport protocol. As emerging technology, the Metaverse brings up a lot of challenges to technologies such as information display, image processing, fast computing and networking. Some of the requirements are: * Low latency and High-Speed transport to reach services in one-hop and for real-time user interactions * Intelligent control and SLA real-time monitoring to convey the traffic and manage network resources and source/route reselection * Decentralization and Edge Services by positioning the data close to the user * Reducing data sizes through resolution changes, compression, and more efficient encodings 3. Gap Analysis It is known that HTML and HTTP are used to locate a web address, but they do not provide a sufficient technological foundation for the disparate technologies of the Web 3.0. In this regard, the HyperSpace Transaction Protocol (HSTP), as described by [IEEE-P2874], is an evolution of HTTP to connect Metaverse spaces, including all data and entities (e.g. physical people, cities, buildings, objects, and their digital twins). It should be able to enable a fully Fioccola, et al. Expires 11 January 2024 [Page 3] Internet-Draft Metaverse July 2023 augmented experience, bridging Web 3.0 technologies, artificial intelligence, blended realities (digital and physical), and distributed ledger technologies. Similarly, HTML would evolve in the direction of something like HyperSpace Modeling Language (HSML). Looking at the transport and network layer, there are the same gaps which needs to be overcame too. There are elaborate solutions for dealing with bandwidth limitations, network congestion, lossy transport protocols, and the ever growing size of video data, to address the above requirements, for instance: * MPTCP[RFC8684] and MPQUIC[I-D.ietf-quic-multipath] are the expansions of TCP[RFC9293] and QUIC[RFC9000] in order to dispatch packets over multiple paths to maximize throughput. * Dynamic Adaptive Streaming over HTTP (DASH) aim to improve the viewport quality of immersive videos by refining the tiles delivery. But client-driven nature of DASH introduces less control on the server side. * Media over QUIC (MoQ) ([I-D.ietf-moq-requirements]) and extensions such as QuicR ([I-D.jennings-moq-proto]) use similar concepts and delivery mechanisms to those used by CDN and named objects. There are fundamental characteristics that QuicR provides for ultra low latency delivery, by leveraging the characteristics of QUIC protocol. * The APplication-aware Networking (APN) aims to develop a framework to enable fine-granularity network service provisioning (traffic operations) within the network domain(s) that supports APN ([I-D.li-apn-framework]). APN aims to use the ability to apply policies to traffic flows entering into the infrastructure. In modern networks, where things such as deterministic networking and networking slicing are required, there is a requirement for more functionality than QoS can provide. * The Computing-Aware Traffic Steering (CATS) aims to analyze the problem on the edge node, which makes a decision based on the metrics of interest, and then steers the traffic to a node that serves a service instance. Indeed, for AR/VR services, the performance experienced by the end users depends on both network metrics such as bandwidth and latency, and compute metrics such as processing, storage capabilities, and capacity. Fioccola, et al. Expires 11 January 2024 [Page 4] Internet-Draft Metaverse July 2023 In all of these approaches, the Metaverse is considered as an overlay application with corresponding infrastructure dependencies, but this increases the current gaps (and resulting costs and technical complexity) between distributed applications and the underlying network architecture. Additionally, it is important to understand which networking technology can be aligned with HSTP [IEEE-P2874]. Given that the current Internet stack is host driven, it is misaligned with the application layer that is data driven. 4. Solution with an ICN approach The Information-Centric Networking (ICN) introduces named information objects, e.g. media contents, as the central concept as opposed to a physical computer, or node ([RFC7927]). In ICN approaches, the principal paradigm is not host-to-host communication as in the current Internet architecture. The increasing demand for highly scalable and efficient distribution of content has motivated the development of architectures that focus on information objects, their properties, and receiver interest in the network to achieve efficient and reliable distribution of such objects. Therefore, for the Metaverse, it would be better to assume information-centric system where most applications participate in granular 3D content exchange, context-aware integration with the physical world, and other Metaverse-relevant services. The assumption is that the Metaverse is an information-centric concept that will become synonymous with the network itself. 4.1. Technical challenges Many applications already work with data-oriented paradigms. Mapping them to a host-centric network model creates complexities and robustness issues, which can be addressed with an ICN oriented approach. The overlay approach to deal with real-time interactive media adds significant complexity. It is needed a fine-grained, hierarchical media exchange for low-latency interactive communication that enables scalable multi-destination distribution, and in-network replication and transformation that exposes object hierarchy for fine grained access and security. Fioccola, et al. Expires 11 January 2024 [Page 5] Internet-Draft Metaverse July 2023 Since the Metaverse is an extension of the Web into immersive XR modalities that are often aligned with physical space, leveraging ICN concepts provides support for decentralized publishing, content interoperability and co-existence, based on general building blocks and not within separated application silos as today’s initial prototypes. There are four ICN capabilities critical to Metaverse concepts: * scalable and robust multi-destination communication, overcoming IP multicast challenges such as inter-domain routing, scalability, and routing communication overhead; * leveraging wireless broadcast to support shared local views and low-latency interactivity; * privacy, selective attention, content filtering, and autonomous interactions, as well as ownership and control on the publishing side; * supporting in-network processing for objects replication and transformation. In addition, the interoperability aspects also need to be investigated, and, for example, Hybrid Information-Centric Networking (hICN), which implements information-networking functionalities into IPv6 ([I-D.muscariello-intarea-hicn], can provide a solution. It would be theoretically possible to leverage the solutions mentioned in the previous section in order to reach the above ICN oriented capabilities. But a systemic approach would be highly desirable in the longer term. 5. Security Considerations TBD 6. IANA Considerations This document makes no request of IANA. 7. Contributors TBD Fioccola, et al. Expires 11 January 2024 [Page 6] Internet-Draft Metaverse July 2023 8. Acknowledgements TBD 9. Informative References [I-D.han-iccrg-arvr-transport-problem] Han, L. and K. Smith, "Problem Statement: Transport Support for Augmented and Virtual Reality Applications", Work in Progress, Internet-Draft, draft-han-iccrg-arvr- transport-problem-01, 12 March 2017, . [I-D.ietf-moq-requirements] Gruessing, J. and S. Dawkins, "Media Over QUIC - Use Cases and Requirements for Media Transport Protocol Design", Work in Progress, Internet-Draft, draft-ietf-moq- requirements-00, 5 June 2023, . [I-D.ietf-quic-multipath] Liu, Y., Ma, Y., De Coninck, Q., Bonaventure, O., Huitema, C., and M. Kühlewind, "Multipath Extension for QUIC", Work in Progress, Internet-Draft, draft-ietf-quic-multipath-04, 13 March 2023, . [I-D.jennings-moq-proto] Jennings, C. F. and S. Nandakumar, "QuicR - Media Delivery Protocol over QUIC", Work in Progress, Internet-Draft, draft-jennings-moq-proto-00, 13 March 2023, . [I-D.li-apn-framework] Li, Z., Peng, S., Voyer, D., Li, C., Liu, P., Cao, C., and G. S. Mishra, "Application-aware Networking (APN) Framework", Work in Progress, Internet-Draft, draft-li- apn-framework-07, 3 April 2023, . [I-D.muscariello-intarea-hicn] Muscariello, L., Carofiglio, G., Auge, J., Papalini, M., and M. Sardara, "Hybrid Information-Centric Networking", Work in Progress, Internet-Draft, draft-muscariello- Fioccola, et al. Expires 11 January 2024 [Page 7] Internet-Draft Metaverse July 2023 intarea-hicn-04, 20 May 2020, . [IEEE-P2874] "IEEE SA P2874 Standard for Spatial Web Protocol, Architecture and Governance", n.d., . [RFC7927] Kutscher, D., Ed., Eum, S., Pentikousis, K., Psaras, I., Corujo, D., Saucez, D., Schmidt, T., and M. Waehlisch, "Information-Centric Networking (ICN) Research Challenges", RFC 7927, DOI 10.17487/RFC7927, July 2016, . [RFC8684] Ford, A., Raiciu, C., Handley, M., Bonaventure, O., and C. Paasch, "TCP Extensions for Multipath Operation with Multiple Addresses", RFC 8684, DOI 10.17487/RFC8684, March 2020, . [RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based Multiplexed and Secure Transport", RFC 9000, DOI 10.17487/RFC9000, May 2021, . [RFC9293] Eddy, W., Ed., "Transmission Control Protocol (TCP)", STD 7, RFC 9293, DOI 10.17487/RFC9293, August 2022, . Authors' Addresses Giuseppe Fioccola Huawei Technologies Palazzo Verrocchio, Centro Direzionale Milano 2 20054 Segrate (Milan) Italy Email: giuseppe.fioccola@huawei.com Paulo Mendes Airbus 82024 Taufkirchen Germany Email: paulo.mendes@airbus.com Fioccola, et al. Expires 11 January 2024 [Page 8] Internet-Draft Metaverse July 2023 Jeff Burke UCLA REMAP 102 East Melnitz Hall Los Angeles, CA 90095 United States of America Email: jburke@remap.ucla.edu Dirk Kutscher HKUST(GZ) Guangzhou China Email: ietf@dkutscher.net Fioccola, et al. Expires 11 January 2024 [Page 9]