NFV RG CJ. Bernardos Internet-Draft UC3M Intended status: Experimental A. Mourad Expires: September 6, 2018 InterDigital March 5, 2018 IPv6-based discovery and association of Virtualization Infrastructure Manager (VIM) and Network Function Virtualization Orchestrator (NFVO) draft-bernardos-nfvrg-vim-discovery-00 Abstract Virtualized resources do not need to be limited to those available in traditional data centers, where the infrastructure is stable, static, typically homogeneous and managed by a single admin entity. Computational capabilities are becoming more and more ubiquitous, with terminal devices getting extremely powerful, as well as other types of devices that are close to the end users at the edge (e.g., vehicular onboard devices for infotainment, micro data centers deployed at the edge, etc.). It is envisioned that these devices would be able to offer storage, computing and networking resources to nearby network infrastructure, devices and things (the fog paradigm). These resources can be used to host functions, for example to offload/complement other resources available at traditional data centers, but also to reduce the end-to-end latency or to provide access to specialized information (e.g., context available at the edge) or hardware. This document describes mechanisms allowing dynamic discovery of virtualization resources and orchestrators in IPv6-based networks. New IPv6 neighbor discovery options are defined. 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." Bernardos & Mourad Expires September 6, 2018 [Page 1]
Internet-Draft VIM+NFVI discovery March 2018 This Internet-Draft will expire on September 6, 2018. Copyright Notice Copyright (c) 2018 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Network Function Virtualization . . . . . . . . . . . . . . . 4 4. Fog Virtualization Overview . . . . . . . . . . . . . . . . . 7 5. Problem statemement . . . . . . . . . . . . . . . . . . . . . 8 6. Advertisement and discovery of mobile resources (VIM+NFVI) . 9 6.1. IPv6 ND-based discovery . . . . . . . . . . . . . . . . . 11 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 8. Security Considerations . . . . . . . . . . . . . . . . . . . 11 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 10.1. Normative References . . . . . . . . . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 1. Introduction The telecommunications sector is experiencing a major revolution that will shape the way networks and services are designed and deployed for the next decade. We are witnessing an explosion in the number of applications and services demanded by users, which are now really capable of accessing them on the move. In order to cope with such a demand, some network operators are looking at the cloud computing paradigm, which enables a potential reduction of the overall costs by outsourcing communication services from specific hardware in the operator's core to server farms scattered in data centers. These services have different characteristics if compared with conventional IT services that have to be taken into account in this cloudification process. Also the transport network is affected in that it is Bernardos & Mourad Expires September 6, 2018 [Page 2]
Internet-Draft VIM+NFVI discovery March 2018 evolving to a more sophisticated form of IP architecture with trends like separation of control and data plane traffic, and more fine- grained forwarding of packets (beyond looking at the destination IP address) in the network to fulfill new business and service goals. Virtualization of functions also provides operators with tools to deploy new services much faster, as compared to the traditional use of monolithic and tightly integrated dedicated machinery. As a natural next step, mobile network operators need to re-think how to evolve their existing network infrastructures and how to deploy new ones to address the challenges posed by the increasing customers' demands, as well as by the huge competition among operators. All these changes are triggering the need for a modification in the way operators and infrastructure providers operate their networks, as they need to significantly reduce the costs incurred in deploying a new service and operating it. Some of the mechanisms that are being considered and already adopted by operators include: sharing of network infrastructure to reduce costs, virtualization of core servers running in data centers as a way of supporting their load- aware elastic dimensioning, and dynamic energy policies to reduce the monthly electricity bill. However, this has proved to be tough to put in practice, and not enough. Indeed, it is not easy to deploy new mechanisms in a running operational network due to the high dependency on proprietary (and sometime obscure) protocols and interfaces, which are complex to manage and often require configuring multiple devices in a decentralized way. Network function virtualization (NFV) [etsi_nfv_whitepaper] and software defined networking (SDN) [onf_sdn_architecture] are changing the way the telecommunications sector will deploy, extend and operate their networks. The ETSI NFV Industry Specification Group (ISG) is developing the baseline NFV architecture, under some assumptions to make this development easier. One of these assumptions is that the resources used to run the virtualized functions are well known in advance by the management and orchestration entities, as well as stable. This document goes beyond this assumption [I-D.irtf-nfvrg-gaps-network-virtualization], by describing mechanisms allowing dynamic discovery of virtualization resources and orchestrators in IPv6-based networks. 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. While [RFC2119] describes interpretations of these key words in terms of protocol specifications and implementations, they are used in this Bernardos & Mourad Expires September 6, 2018 [Page 3]
Internet-Draft VIM+NFVI discovery March 2018 document to describe requirements for the SFC mechanisms to efficiently enable fog RAN. The following terms used in this document are defined by the ETSI NFV ISG, the ONF and the IETF: NFV Infrastructure (NFVI): totality of all hardware and software components which build up the environment in which VNFs are deployed NFV Management and Orchestration (NFV-MANO): functions collectively provided by NFVO, VNFM, and VIM. NFV Orchestrator (NFVO): functional block that manages the Network Service (NS) lifecycle and coordinates the management of NS lifecycle, VNF lifecycle (supported by the VNFM) and NFVI resources (supported by the VIM) to ensure an optimized allocation of the necessary resources and connectivity. Virtualized Infrastructure Manager (VIM): functional block that is responsible for controlling and managing the NFVI compute, storage and network resources, usually within one operator's Infrastructure Domain. Virtualized Network Function (VNF): implementation of a Network Function that can be deployed on a Network Function Virtualisation Infrastructure (NFVI). Virtualized Network Function Manager (VNFM): functional block that is responsible for the lifecycle management of VNF. 3. Network Function Virtualization The ETSI ISG NFV is a working group which, since 2012, aims to evolve quasi-standard IT virtualization technology to consolidate many network equipment types into industry standard high volume servers, switches, and storage. It enables implementing network functions in software that can run on a range of industry standard server hardware and can be moved to, or loaded in, various locations in the network as required, without the need to install new equipment. The ETSI NFV is one of the predominant NFV reference framework and architectural footprints [nfv_sota_research_challenges]. The ETSI NFV framework architecture framework is composed of three domains (Figure 1): o Virtualized Network Function, running over the NFVI. Bernardos & Mourad Expires September 6, 2018 [Page 4]
Internet-Draft VIM+NFVI discovery March 2018 o NFV Infrastructure (NFVI), including the diversity of physical resources and how these can be virtualized. NFVI supports the execution of the VNFs. o NFV Management and Orchestration, which covers the orchestration and life-cycle management of physical and/or software resources that support the infrastructure virtualization, and the life-cycle management of VNFs. NFV Management and Orchestration focuses on all virtualization specific management tasks necessary in the NFV framework. +-------------------------------------------+ +---------------+ | Virtualized Network Functions (VNFs) | | | | ------- ------- ------- ------- | | | | | | | | | | | | | | | | | VNF | | VNF | | VNF | | VNF | | | | | | | | | | | | | | | | | ------- ------- ------- ------- | | | +-------------------------------------------+ | | | | +-------------------------------------------+ | | | NFV Infrastructure (NFVI) | | NFV | | ----------- ----------- ----------- | | Management | | | Virtual | | Virtual | | Virtual | | | and | | | Compute | | Storage | | Network | | | Orchestration | | ----------- ----------- ----------- | | | | +---------------------------------------+ | | | | | Virtualization Layer | | | | | +---------------------------------------+ | | | | +---------------------------------------+ | | | | | ----------- ----------- ----------- | | | | | | | Compute | | Storage | | Network | | | | | | | ----------- ----------- ----------- | | | | | | Hardware resources | | | | | +---------------------------------------+ | | | +-------------------------------------------+ +---------------+ Figure 1: ETSI NFV framework The NFV architectural framework identifies functional blocks and the main reference points between such blocks. Some of these are already present in current deployments, whilst others might be necessary additions in order to support the virtualization process and consequent operation. The functional blocks are (Figure 2): o Virtualized Network Function (VNF). o Element Management (EM). Bernardos & Mourad Expires September 6, 2018 [Page 5]
Internet-Draft VIM+NFVI discovery March 2018 o NFV Infrastructure, including: Hardware and virtualized resources, and Virtualization Layer. o Virtualized Infrastructure Manager(s) (VIM). o NFV Orchestrator. o VNF Manager(s). o Service, VNF and Infrastructure Description. o Operations and Business Support Systems (OSS/BSS). +--------------------+ +-------------------------------------------+ | ---------------- | | OSS/BSS | | | NFV | | +-------------------------------------------+ | | Orchestrator +-- | | ---+------------ | | +-------------------------------------------+ | | | | | --------- --------- --------- | | | | | | | EM 1 | | EM 2 | | EM 3 | | | | | | | ----+---- ----+---- ----+---- | | ---+---------- | | | | | | |--|-| VNF | | | | ----+---- ----+---- ----+---- | | | manager(s) | | | | | VNF 1 | | VNF 2 | | VNF 3 | | | ---+---------- | | | ----+---- ----+---- ----+---- | | | | | +------|-------------|-------------|--------+ | | | | | | | | | | | +------+-------------+-------------+--------+ | | | | | NFV Infrastructure (NFVI) | | | | | | ----------- ----------- ----------- | | | | | | | Virtual | | Virtual | | Virtual | | | | | | | | Compute | | Storage | | Network | | | | | | | ----------- ----------- ----------- | | ---+------ | | | +---------------------------------------+ | | | | | | | | Virtualization Layer | |--|-| VIM(s) +-------- | | +---------------------------------------+ | | | | | | +---------------------------------------+ | | ---------- | | | ----------- ----------- ----------- | | | | | | | Compute | | Storage | | Network | | | | | | | | hardware| | hardware| | hardware| | | | | | | ----------- ----------- ----------- | | | | | | Hardware resources | | | NFV Management | | +---------------------------------------+ | | and Orchestration | +-------------------------------------------+ +--------------------+ Figure 2: ETSI NFV reference architecture Bernardos & Mourad Expires September 6, 2018 [Page 6]
Internet-Draft VIM+NFVI discovery March 2018 4. Fog Virtualization Overview Virtualization is invading all domains of the E2E 5G network, including the access, as a mean to achieve the necessary flexibility in support of the E2E slicing concept. The ETSI NFV framework is the cornerstone for making virtualization such a promising technology that can be matured in time for 5G. Typically, virtualization has been mostly envisaged in the core network, where sophisticated data centers and clouds provided the right substrate. And mostly, the framework focused on virtualizing network functions, so called VNFs (virtualized network functions), which were somewhat limited to functions that are delay tolerant, typically from the core and aggregation transport. As the community has recently been developing the 5G applications and their technical requirements, it has become clear that certain applications would require very low latency which is extremely challenging and stressing for the network to deliver through a pure centralized architecture. The need to provide networking, computing, and storage capabilities closer to the users has therefore emerged, leading to what is known today as the concept of intelligent edge. ETSI has been the first to address this need recently by developing the framework of mobile edge computing (MEC). Such an intelligent edge could not be envisaged without virtualization. Beyond applications, it raises a clear opportunity for networking functions to execute at the edge benefiting from inherent low latencies. Whilst it is appreciated the particular challenge for the intelligent edge concept in dealing with mobile users, the edge virtualization substrate has been largely assumed to be fixed or stationary. Although little developed, the intelligent edge concept is being extended further to scenarios where for example the edge computing substrate is on the move, e.g., on-board a car or a train, or that it is distributed further down the edge, even integrating resources from different stakeholders, into what is known as the fog. The challenges and opportunities for such extensions of the intelligent edge remain an exciting area of future research. Figure 3 shows a diagram representing the fog virtualization concept. The fog is composed by virtual resources on top of heterogeneous resources available at the edge and even further in the RAN and end- user devices. These resources are therefore owned by different stakeholders who collaboratively form a single hosting environment for the VNFs to run. As an example, virtual resources provided to the fog might be running on eNBs, APs, at micro data centers deployed in shopping malls, cars, trains, etc. The fog is connected to data Bernardos & Mourad Expires September 6, 2018 [Page 7]
Internet-Draft VIM+NFVI discovery March 2018 centers deeper into the network architecture (at the edge ir the core). On the top part of the figure, an example of user and control plane VNFs is shown. User plane VNFs are represented as "fx", and control ones as "ctrlx". Depending on the functionality implemented by these VNFs and the service requirements, these VNFs would be mapped (i.e., instantiated) differently to the physical resouces (as described in [I-D.aranda-sfc-dp-mobile]). -------- --------- --------- control | ctr1 |........................| ctrl2 |...| ctrl3 | plane -------- --------- --------- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ------ ------ ------ .| f3 |.........| f5 |.....| f6 | ------ ------ . ------ ------ ------ user | f1 |.......| f2 |. . plane ------ ------ . ------ . .| f4 |............. ------ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +--------------------------------+ +-------------------+ | ------- -------- -------- | | ---------- | | | | | | | | | | ---------- | | | | @UE | | @car | | @eNB | | | ---------- | | | | ------- -------- -------- | | | Data | | | | | | | | Center | | - | | -------- Heterogeneous ------- | | | (DC) |- | phy | | | computing | | | | ---------- | infra | |@train| devices | @AP | |==| ---------- | | -------- forming ------- | | ---------- | | | the fog | | ---------- | | | | --------- ------------ | | | Data | | | | | | | | | | | | Center | | - | | | @mall | | @localDC | | | | (DC) |- | | --------- ------------ | | ---------- | | FOG | | CLOUD | +--------------------------------+ +-------------------+ <--------- fog and edge -----------------> <--- edge & central cloud ---> Figure 3: Fog virtualization 5. Problem statemement Virtualized resources do not need to be limited to those available in traditional data centers, where the infrastructure is stable, static, typically homogeneous and managed by a single admin entity. Computational capabilities are becoming more and more ubiquitous, Bernardos & Mourad Expires September 6, 2018 [Page 8]
Internet-Draft VIM+NFVI discovery March 2018 with terminal devices getting extremely powerful, as well as other types of devices that are close to the end users at the edge (e.g., vehicular onboard devices for infotainment, micro data centers deployed at the edge, etc.). It is envisioned that these devices would be able to offer storage, computing and networking resources to nearby network infrastructure, devices and things (the fog paradigm). These resources can be used to host functions, for example to offload/complement other resources available at traditional data centers, but also to reduce the end-to-end latency or to provide access to specialized information (e.g., context available at the edge) or hardware. Since the fog resources are volatile, i.e. may dynamically appear and disappear, and may be mobile, i.e. may move from one place to another, mechanisms to discover and advertise virtualized fog resources are required. Taking ETSI NFV architecture (see Section 3) as a baseline for the virtualization of the fog nodes, the discovery of a virtualization resource can be done either through (i) the discovery of NFVI from a VIM; or through (ii) the discovery of VIMs and associated NFVI from an NFVO. In this document we focus on the alternative ii) that is the discovery of the VIMs and NFVI from an NFVO. This is so because a VIM is typically NFVI-specific, and therefore these two are more often than not tied together. The relationship between an NFVO and the resources it is capable to orchestrate through a VIM is statically defined according to the current ETSI NFV specifications [etsi_nfv_002] [etsi_nfv_ifa_005]. The interface Or-Vi (between NFVO and VIM) [etsi_nfv_ifa_005] does not include any discovery and automatic registration of (mobile) VIMs from a (mobile) NFVO. 6. Advertisement and discovery of mobile resources (VIM+NFVI) This document describes IPv6 extensions to allow discovery of virtualization resources, in the form of a VIM + associated NFVI. Examples of scenarios where this is useful are shown in Figure 4 and Figure 5, including also a high-level view of the solution. Bernardos & Mourad Expires September 6, 2018 [Page 9]
Internet-Draft VIM+NFVI discovery March 2018 __ ___________ _( )_ ------------ _( )_ ----------- _( )_ | terminal |-(_ VIM--NFVI _) | network |-(_ NFVO _) ------------ (___________) ----------- (_ _) | | (__) XXX (1. attachment) | | | +---2. Advertisement----------->| | | |<......(3. VIM Registration)...+ | | Figure 4: VIM+NFVI advertisement Figure 4 shows an scenario in which a mobile terminal with available resources (NFVI, and associated VIM) attaches to a network (step 1). Then, it advertises (step 2) that it has virtualization resources (and their characteristics, such as the type of VIM) that could be eventually used. An NFVO sitting in the network can then decide to register the VIM for later use (step 3). This document specifies some options for step 2 based on IP signaling. Step 3 is implementation dependent and very much VIM-NFVO specific. Similarly, Figure 5 shows a scenario with a mobile NFVO. A mobile terminal with an embedded NFVO attaches to a network (step 1). Then, it queries the network (step 2) to learn if there are virtualization resources available. If so, the network conveys that information (step 3). The NFVO can then decide to register the VIM for later use (step 4). This document specifies some options for steps 2 and 3 based on IP signaling. Step 4 is implementation dependent and very much VIM-NFVO specific. Bernardos & Mourad Expires September 6, 2018 [Page 10]
Internet-Draft VIM+NFVI discovery March 2018 ___________ _( )_ ______ _( +-NFVI )_ ------------ _( )_ ----------- _( / )_ | terminal |-(_ NFVO _) | network |-(_ VIM(s)---NFVI _) ------------ (______) ----------- (_ \ _) | | (_ +-NFVI _) XXX (1. attachment) | (___________) | | +---2. Request----------------->| | | |<-----------3. Advertisement---| | | +...(4. VIM Registration)......>| | | Figure 5: VIM+NFVI discovery 6.1. IPv6 ND-based discovery TBD. 7. IANA Considerations N/A. 8. Security Considerations TBD. 9. Acknowledgments The work in this draft will be further developed and explored under the framework of the H2020 5G-CORAL project (Grant 761586). 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, <https://www.rfc-editor.org/info/rfc2119>. Bernardos & Mourad Expires September 6, 2018 [Page 11]
Internet-Draft VIM+NFVI discovery March 2018 10.2. Informative References [etsi_nfv_002] ""Network Functions Virtualization (NFV); Architectural Framework," ETSI GS NFV 002 v1.1.1", October 2013. [etsi_nfv_ifa_005] ""Network Functions Virtualisation (NFV) Release 2; Management and Orchestration; Or-Vi reference point - Interface and Information Model Specification," ETSI GS NFV-IFA 005 V2.3.1", August 2017. [etsi_nfv_whitepaper] "Network Functions Virtualisation (NFV). White Paper 2", October 2014. [I-D.aranda-sfc-dp-mobile] Gutierrez, P., Gramaglia, M., Lopez, D., and W. Haeffner, "Service Function Chaining Dataplane Elements in Mobile Networks", draft-aranda-sfc-dp-mobile-04 (work in progress), June 2017. [I-D.irtf-nfvrg-gaps-network-virtualization] Bernardos, C., Rahman, A., Zuniga, J., Contreras, L., Aranda, P., and P. Lynch, "Network Virtualization Research Challenges", draft-irtf-nfvrg-gaps-network- virtualization-09 (work in progress), February 2018. [nfv_sota_research_challenges] Mijumbi, R., Serrat, J., Gorricho, J-L., Bouten, N., De Turck, F., and R. Boutaba, "Network Function Virtualization: State-of-the-art and Research Challenges", IEEE Communications Surveys & Tutorials Volume: 18, Issue: 1, September 2015. [onf_sdn_architecture] "SDN Architecture (Issue 1.1), ONF TR-521", February 2016. Authors' Addresses Bernardos & Mourad Expires September 6, 2018 [Page 12]
Internet-Draft VIM+NFVI discovery March 2018 Carlos J. Bernardos Universidad Carlos III de Madrid Av. Universidad, 30 Leganes, Madrid 28911 Spain Phone: +34 91624 6236 Email: cjbc@it.uc3m.es URI: http://www.it.uc3m.es/cjbc/ Alain Mourad InterDigital Europe Email: Alain.Mourad@InterDigital.com URI: http://www.InterDigital.com/ Bernardos & Mourad Expires September 6, 2018 [Page 13]