NMRG LM. Contreras Internet-Draft Telefonica Intended status: Informational October 24, 2021 Expires: April 27, 2022 Evolution of Cooperating Layered SDN Architecture including Compute and Data Awareness draft-contreras-nmrg-clas-evolution-00 Abstract This document proposes the extension of the Cooperating Layered Architecture for Software-Defined Networking (SDN) framework by including Compute and Data Awareness. 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 April 27, 2022. Copyright Notice Copyright (c) 2021 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. Contreras Expires April 27, 2022 [Page 1] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Cooperating Layered Architecture for Software-Defined Networking (CLAS) . . . . . . . . . . . . . . . . . . . . . . 2 3. Augmentation of CLAS with Compute and Data Awareness . . . . 5 3.1. Compute Stratum . . . . . . . . . . . . . . . . . . . . . 5 3.2. Learning Plane . . . . . . . . . . . . . . . . . . . . . 5 3.3. Extended CLAS architecture . . . . . . . . . . . . . . . 6 4. TODO for next versions of this document . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction Current telecommunication networks are evolving towards a tight integration of interconnected compute environments, offering capabilities for the instantiation of virtualized network functions interworking with physical variants of other network functions, altogether constituting services end-to-end. Moreover, network operations are complementing the capabilities of automation and programmability with the introduction of Artificial Intelligence (AI) and Machine Learning (ML) techniques to facilitate informed decisions as well as predictive behavior enabling consistent closed loop automation. It is then necessary to provide a network management framework that could incorporate these trends in a smooth manner, structuring the different concerns and the interaction among components operating the network. This document describes the evolution of one of those frameworks, named Cooperating Layered Architecture for Software-Defined Networking (CLAS) [RFC8597] to include the aforementioned aspects into the architecture. 2. Cooperating Layered Architecture for Software-Defined Networking (CLAS) [RFC8597] describes an SDN architecture structured in two different strata, namely Service Stratum and Transport Stratum. On one hand, the Service Stratum contains the functions related to the provision of services and the capabilities offered to external applications. On the other hand, the Transport Stratum comprises the functions Contreras Expires April 27, 2022 [Page 2] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 focused on the transfer of data between the communication endpoints (e.g., between end-user devices, between two service gateways, etc.). Each of the strata is structured in different planes, as follows: o The Control plane, which centralizes the control functions of each stratum and directly controls the corresponding resources. o The Management plane, logically centralizing the management functions for each stratum, including the management of the control and resource planes. o The Resource plane, that comprises the resources for either the transport or the service functions. Figure 1 illustrates original CLAS architecture. Contreras Expires April 27, 2022 [Page 3] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 Applications /\ || || +-------------------------------------||-------------+ | Service Stratum || | | \/ | | ........................... | | . SDN Intelligence . | | . . | | +--------------+ . +--------------+ . | | | Resource Pl. | . | Mgmt. Pl. | . | | | |<===>. +--------------+ | . | | | | . | Control Pl. | | . | | +--------------+ . | |-----+ . | | . | | . | | . +--------------+ . | | ........................... | | /\ | | || | +-------------------------------------||-------------+ || Standard -- || -- API || +-------------------------------------||-------------+ | Transport Stratum || | | \/ | | ........................... | | . SDN Intelligence . | | . . | | +--------------+ . +--------------+ . | | | Resource Pl. | . | Mgmt. Pl. | . | | | |<===>. +--------------+ | . | | | | . | Control Pl. | | . | | +--------------+ . | |-----+ . | | . | | . | | . +--------------+ . | | ........................... | | | | | +----------------------------------------------------+ Figure 1: Cooperating Layered Architecture for SDN Contreras Expires April 27, 2022 [Page 4] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 3. Augmentation of CLAS with Compute and Data Awareness The CLAS architecture was initially conceived from the perspective of exploiting the advantages of network programmability in operational networks. The evolution of current telecommunication services and networks are however introducing new aspects to consider. o Consideration of distributed computing capabilities attached to different points in the network, intended for hosting a variety of services and applications usually in a virtualized manner (e.g., [I-D.contreras-alto-service-edge]). o Introduction of Artificial Intelligence (AI) and Machine Learning (ML) techniques in order to improve operations by means of closed loop automation (e.g., [I-D.pedro-nmrg-ai-framework]). With that in mind, this memo proposes augmentation to the original CLAS proposition by adding the aforementioned aspects. 3.1. Compute Stratum For the first aspect, the CLAS architecture is extended by adding a new stratum, named Compute Stratum. The objective is to contain in this stratum the control, management and resource planes related to the computing part. As in the other two strata, the mission is to make this additional stratum cooperate with the other two in order to facilitate the overall service provision in the network. With this addition, and in order to be more explicit in the strata scope, the previously named Transport Stratum is renamed as Network Stratum, representing the fact that this stratum responsibility is focused on the overall connectivity supporting the other two strata in the architecture. 3.2. Learning Plane A further extension to the original CLAS architecture is related to the need of collecting, processing and sharing relevant data from each of the considered strata. With that purpose a Learning Plane is proposed to complement the already existing planes per stratum. The learning plane will be in charge of handling the data specificities of each particular stratum. Thus, the learning plane in the Service Stratum is focused on data relevant to the service as defined by the application or service owner, usually in terms of service key performance indicators (KPI) [TMV]. Then, the learning Contreras Expires April 27, 2022 [Page 5] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 plane in the compute stratum concentrates on data related to the computing capabilities in use (e.g., CPU load, RAM usage, storage utilization, etc) [OpenStack]. Finally, the learning plane in the network stratum is in charge of handling the monitoring and telemetry information obtained from the network (e.g., [I-D.ietf-opsawg-service-assurance-yang]). 3.3. Extended CLAS architecture Figure 2 presents the augmentation proposed showing the relationship among strata. Applications /\ || +-------------------------------------||-------------+ | Service Stratum || | | \/ | | +--------------+ ........................... | | | Learning Pl. | . SDN Intelligence . | | | |<===>. . | | +-----/\-------+ . +--------------+ . | | || . | Mgmt. Pl. | . | | || . +--------------+ | . | | +-----\/-------+ . | Control Pl. |-----+ . | | | Resource Pl. | . | | . | | | |<===>. +--------------+ . | | +--------------+ ........................... | | /\ /\ | | || || | +--------------------------------||-------------||---+ Standard API -- || -- || +--------------------------------||-----+ || | Compute Stratum || | || | \/ | || | +----------+ ................... | || | | Learning | . SDN . | Std. || | | Plane |<==>. Intelligence . | API || | +-----/\---+ . +----------+ . | -- || -- | || . | Mgmt. Pl.| . | || | || . +----------+ | . | || | +-----\/---+ . | Control |-+ . | || | | Resource | . | Plane | . | || | | Plane |<==>. +----------+ . | || | +----------+ ................... | || +----------------------------------/\---+ || Standard API -- || -- || Contreras Expires April 27, 2022 [Page 6] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 +-------------------||-----------||-----+ | Network Stratum || || | | \/ \/ | | +----------+ ................... | | | Learning | . SDN . | | | Plane |<==>. Intelligence . | | +-----/\---+ . +----------+ . | | || . | Mgmt. Pl.| . | | || . +----------+ | . | | +-----\/---+ . | Control |-+ . | | | Resource | . | Plane | . | | | Plane |<==>. +----------+ . | | +----------+ ................... | +---------------------------------------+ Figure 2: Extended CLAS architecture 4. TODO for next versions of this document This version is a work-in-progress. Next versions of the document will address somo further aspects such as: o Communication between strata (and planes). o Deployment scenarios (including legacy ones). o Potential use cases (specially in alignment with on-going activities in NMRG). 5. Security Considerations Same security considerations as reflected in [RFC8597] with regards to the strata architecture apply also here. Apart from that, the introduction of the Learning plane on the data management imposes additional security concerns. (TODO: elaborate on data-related security issues). 6. IANA Considerations This draft does not include any IANA considerations 7. References Contreras Expires April 27, 2022 [Page 7] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 [I-D.contreras-alto-service-edge] Contreras, L. M., Lachos, D. A., Rothenberg, C. E., and S. Randriamasy, "Use of ALTO for Determining Service Edge", draft-contreras-alto-service-edge-03 (work in progress), July 2021. [I-D.ietf-opsawg-service-assurance-yang] Claise, B., Quilbeuf, J., Lucente, P., Fasano, P., and T. Arumugam, "YANG Modules for Service Assurance", draft- ietf-opsawg-service-assurance-yang-01 (work in progress), July 2021. [I-D.pedro-nmrg-ai-framework] Martinez-Julia, P., Homma, S., and D. R. Lopez, "Artificial Intelligence Framework for Network Management", draft-pedro-nmrg-ai-framework-00 (work in progress), October 2021. [OpenStack] "OpenStack performance documentation", https://docs.openstack.org/developer/performance-docs/ index.html . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC8597] Contreras, LM., Bernardos, CJ., Lopez, D., Boucadair, M., and P. Iovanna, "Cooperating Layered Architecture for Software-Defined Networking (CLAS)", RFC 8597, DOI 10.17487/RFC8597, May 2019, . [TMV] "Service performance measurement methods over 5G experimental networks", 5G-PPP TMV white paper , May 2021. Acknowledgments The work of L.M. Contreras has been partly funded by the European Commission through the H2020 project 5GROWTH (Grant Agreement no. 856709). Author's Address Contreras Expires April 27, 2022 [Page 8] Internet-DrafCLAS Evolution with Compute and Data Awareness October 2021 Luis M. Contreras Telefonica Ronda de la Comunicacion, s/n Sur-3 building, 3rd floor Madrid 28050 Spain Email: luismiguel.contrerasmurillo@telefonica.com URI: http://lmcontreras.com/ Contreras Expires April 27, 2022 [Page 9]