NFV Research Group S. Jeon Internet-Draft Instituto de Telecomunicacoes Intended status: Informational Y. Kim Expires: April 21, 2016 Soongsil University October 19, 2015 VNFaaS for Dynamic Resource Provisioning in Non-Virtualized Networks draft-sijeon-nfvrg-dynamic-resource-vnfaas-00.txt Abstract This draft describes examples of Virtual Network Function as a Service (VNFaaS) for dynamic resource provisioning in non-virtualized networks, with benefits, while introducing challenges and considerations. 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 http://datatracker.ietf.org/drafts/current/. 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Jeon & Kim Expires April 21, 2016 [Page 1] Internet-Draft VNFaaS for Dynamic Resource Provisioning October 2015 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Examples of Dynamic Resource Provisioning in Non-Virtualized Networks . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.1. Traffic Offloading . . . . . . . . . . . . . . . . . . . 3 2.2. Localized Processing . . . . . . . . . . . . . . . . . . 3 3. Challenges and Considerations . . . . . . . . . . . . . . . . 4 3.1. Integrated monitoring of VNFs and PNFs . . . . . . . . . 4 3.2. Interfacing between VNFs and PNFs . . . . . . . . . . . . 4 3.3. Dependencies verification between the VNFs, VNFs and PNFs 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction NFV promises reduced time-to-market and rapid deployment of novel network solutions by running the network function software instance decoupled from a hardware appliance on top of standard high-volume servers. It is also expected to address operator's issues on the flexibility. However, expecting NFV will totally replace the current 4G equipment in near future would not be realistic, as operators have different replacement schedules and evolution strategies of their networks. The NFV enables various kinds of virtualized services such as NFV Infrastructure as a Service (NFVIaaS), Virtual Network Platform as a Service (VNPaaS), Virtual Network Function as a Service (VNFaaS), and so on [ETSI-NFV-USE-CASES]. VNFaaS could be useful, particularly for dynamic resource provisioning in non-virtualized networks, for addressing dimensioning-related issues while presenting value-added services over the current network deployment, without big burdens of CAPEX and OPEX. This draft describes examples of VNFaaS for dynamic resource provisioning in non-virtualized networks, with benefits, while introducing challenges and considerations. 2. Examples of Dynamic Resource Provisioning in Non-Virtualized Networks The examples of VNFaaS introduced below focus on dynamic resource provisioning with expected benefits and optimization perspectives. Jeon & Kim Expires April 21, 2016 [Page 2] Internet-Draft VNFaaS for Dynamic Resource Provisioning October 2015 The deployed aspects and features can vary and be differently customized depending on the demand of operators. 2.1. Traffic Offloading The rapid increase of data traffic over mobile network is giving big concerns to operator; how to mitigate/offload the increasing traffic while increasing average revenue per user (ARPU). There are already well-known traffic offloading solutions for 3GPP networks, such as Local IP Access (LIPA) and Selective IP Traffic Offloading (SIPTO), which aims to localize traffic, where the target peer could be locally available. Those approaches require additional hardware deployment, such as local gateways (LGWs), where needed over regions, or call for significant changes of the deployed network, thus increasing CAPEX and OPEX. They may be useful at peak hours and days while the usability is at low in the rest of times. Instantiating virtualized EPC (vEPC) with full EPC components could be useful; however, selected VNFs in the vEPC for dynamic resource provisioning could be utilized on demand, which can effectively address the traffic offloading problem faced by the operators. That is, Serving GW (SGW) and PDN GW (PGW) can be served on a regional cloud while those are connected and interfaced with the legacy EPC (physical EPC, pEPC) components to be controlled by such as PCRF and MME in the pEPC. In addition, it is envisaged that different offloading vEPC mode can be programmed to meet more diverse aspects of traffic offloading with granularity, as proposed in [vEPC-TOF]. 2.2. Localized Processing 3GPP Machine-Type Communications (MTC) architecture is dedicated for effectively handling machine-to-machine (M2M), which can be interchangeably called MTC, traffic over a 3GPP network. Characteristics of MTC traffic vary over developed MTC applications. Some MTC applications generate lots of signaling traffic including the subscription control, which may be huge by taking into consideration millions of MTC devices. For effective processing with reduced delay on demand, subscription control function can be additionally provided within the Radio Access Network (RAN) in close proximity to MTC devices, which aspect could be similar with the concept of the ETSI Mobile-Edge Computing (MEC) [ETSI-MEC-Whitepaper]. It may enable localized processing of huge amounts of MTC signaling traffic that should have gone through the MTC core over regional access networks, while contributing to reliability of overall MTC system architecture. Jeon & Kim Expires April 21, 2016 [Page 3] Internet-Draft VNFaaS for Dynamic Resource Provisioning October 2015 3. Challenges and Considerations We briefly mention challenges for the VNFaaS-based dynamic resource provisioning over non-virtualized networks are described with consideration in previously submitted IRTF drafts and scientific publications. More aspects regarding those will be updated in next version. 3.1. Integrated monitoring of VNFs and PNFs Determination, deployment, and initiation of VNFs can be made by a human intervention. However, to decide proper a dynamic resource provisioning strategy in an automated process, it should be able to exactly identify the current situation and determine optimal placement of the VNFs with resource availability. Integrated monitoring of deployed VNFs and Physical Network Functions (PNFs) should be possible. [ETSI-NFV-MANO] introduces several ways of the event monitoring, i.e. VNF-initiated, Element Management (EM)- initiated, OSS/BSS-initiated, and VNF Manager (VNFM)-initiated. One easy way to get the event monitoring of the PNFs could be using OSS/ BSS-initiated. And the NFV Orchestrator should get properly notified from those monitored events. 3.2. Interfacing between VNFs and PNFs It may need to interface between dynamically deployed VNFs and PNFs running over a network, where the VNFs cannot work standalone but requires interfacing for a control plane operation. In case of the traffic offloading scenario, deployed SGW and PGW should be connected with physical MME, and the MME should be able to be aware of newly initiated GWs' context information in a running time. 3.3. Dependencies verification between the VNFs, VNFs and PNFs Once VNFs to be instantiated are determined, it should be identified availability of the VNFs and cloud resource. Then, dependencies verification should be followed, to identify whether there are dependencies issues to be working with other VNFs and PNFs. The need of dependencies of network service components in NFV framework was mentioned in [I-D.shin-nfvrg-service-verification], with an example, i.e. case of inconsistency between states stored and managed in VNF Forwarding Graphs (FGs), however, not covering the dependencies between VNFs and PNFs. One idea to avoid such dependencies could come from policy-based intent statement that regulates specific actions with constraints [I-D.irtf-nfvrg-nfv-policy-arch], which can block undesired actions before instantiation and execution of the determined VNFs, however, Jeon & Kim Expires April 21, 2016 [Page 4] Internet-Draft VNFaaS for Dynamic Resource Provisioning October 2015 it may be difficult to check deeper level of dependencies issues made over the possibility of diverse combination of different kinds of VNFs. 4. IANA Considerations 5. Security Considerations 6. References 6.1. Normative References [I-D.irtf-nfvrg-nfv-policy-arch] Figueira, N., Krishnan, R., Lopez, D., Wright, S., and D. Krishnaswamy, "Policy Architecture and Framework for NFV Infrastructures", draft-irtf-nfvrg-nfv-policy-arch-02 (work in progress), October 2015. 6.2. Informative References [ETSI-MEC-Whitepaper] ETSI, "Mobile-Edge Computing - Introductory Technical White Paper", September 2014. [ETSI-NFV-MANO] ETSI, "Network Function Virtualisation (NFV) Management and Orchestration, v1.1.1", December 2014. [ETSI-NFV-USE-CASES] ETSI, "Network Functions Virtualisation (NFV); Use Cases, v1.1.1", October 2013. [I-D.shin-nfvrg-service-verification] Shin, M., Nam, K., Pack, S., Lee, S., Krishnan, R., and T. Kim, "Verification of NFV Services : Problem Statement and Challenges", draft-shin-nfvrg-service-verification-04 (work in progress), October 2015. [vEPC-TOF] Jeon, S., Corujo, D., and R. Aguiar, "Virtualised EPC for On-Demand Mobile Traffic Offloading in 5G Environments", Proceedings of IEEE Conference on Standards and Communications Networking (CSCN) 2015, October 2015. Jeon & Kim Expires April 21, 2016 [Page 5] Internet-Draft VNFaaS for Dynamic Resource Provisioning October 2015 Authors' Addresses Seil Jeon Instituto de Telecomunicacoes Campus Universitario de Santiago Aveiro 3810-193 Portugal Email: seiljeon@av.it.pt Younghan Kim Soongsil University 369, Sangdo-ro, Dongjak-gu Seoul 156-743 Korea Email: younghak@ssu.ac.kr Jeon & Kim Expires April 21, 2016 [Page 6]