Truong-Xuan Do Internet Draft Younghan Kim Intended status: Informational Soongsil University, Korea Expires: Jan 2017 Jul 7, 2016 Policy-based Service Function Path Adjustment draft-xuan-sfc-policy-sfp-adjustment-00 Abstract This document describes about policy-based SFP adjustment which covers two new use cases for SFP adjustment in addition to existing use cases defined in [ietf-sfc-control-plane] and in [irtf-nfvrg-resource-management]. These two use cases include QoS and affinity policies. 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), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on Jan 2017. Expires January 7,2017 [Page 1] Internet-Draft Jul 7, 2016 Copyright Notice Copyright (c) 2014 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 (http://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. Table of Contents 1. Introduction...................................................3 2. Conventions used in this document..............................3 3. Service Function Path Adjustment...............................3 4. Policy architecture for SFC....................................4 5. Policy-based SFP adjustment....................................5 6. Alignment with control plane document..........................6 7. Security Considerations........................................6 8. IANA Considerations............................................6 9. References.....................................................6 9.1. Normative References......................................6 9.2. Informative References....................................6 Expires January 7,2017 [Page 2] Internet-Draft Jul 7, 2016 1. Introduction The SFP could be dynamically adjusted based on the state and attributes of the SFP components. In some cases, the SFP adjustment is carried out due to the failure of one SFP component or the policies of network operators. This document describes about policy- based SFP adjustment which covers two new use cases for SFP adjustment in addition to existing use cases defined in [ietf-sfc-control-plane] and in [irtf-nfvrg-resource-management]. These two use cases include polices related to Quality of Service treatment and affinity rules. 2. Conventions used in this document 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 RFC-2119 [RFC2119]. The terms about SFC, SFP, SFF, SF, and classifier are defined in [RFC7665] and [ietf-sfc-control-plane] 3. Service Function Path Adjustment As discribed in [RFC7665], the SFP is composed by the combination of different SF instances, SFFs, and classifiers. One SFC can have more than one SFPs. The SFP can be adjusted due to the failure of one SF in the chain or load balancing requirements of the network operators. These use cases are covered in the [ietf-sfc-control-plane] as below: + SFP fail-over + SFP with better latency + Traffic engineered SFP + SF/SFP load-balancing Other use cases are also covered in [irtf-nfvrg-resource-management] + Path Optimization + Energy efficiency Expires January 7,2017 [Page 3] Internet-Draft Jul 7, 2016 4. Policy architecture for SFC Figure 1 shows the policy architecture for service function chain. The policies are described in high level languagues at policy decision point (PDP) which will be translated into subsystem configurations and enforced at enforcement points (PEP). +------------+ | Policy | | decision | +-----+------+ | +------|---------------------------------------+ | +----v------+ | | |Policy | SFC Control Plane | +-------+ |enforcement| | | | +-----------+ | C1 +------------------^-------------^-------------+ +------+--------------|C3+------------------------------------+ | | +----+ | | | | | | SF | |C2 |C2 | | | +-+--+ | | | | +----V--- --+ | | | | | | SFC | +-+--+ +-+---+ +-+---+ | | |Classifier +----^+SFF +-----^+SFF +-------^+SFF | | | | Node +v----+(PEP)v-----+(PEP)+v-------+(PEP)| | | +-----------+ +-+--+ +-+---+ +--+--+ | | | | | | | |C2 ---+--- | | | | | | +----+------+ C4 | | V +-+--+ +--+-+ | SFC Proxy +--> | | | SF | |SF | +-----------+ | | +----+ +----+ | | |C3 |C3 | | SFC Data Plane Components V V | +-------------------------------------------------------------+ Figure 1. Policy architecture for SFC Expires January 7,2017 [Page 4] Internet-Draft Jul 7, 2016 5. Policy-based SFP adjustment We assume that the control plane which is responsible for calculating the SFP has the global view and real-time status of network components such as service function, service function forwarder. The control plane knows the capacity, location of each network component. The control plane also monitors the network metrics: workload, latency, bandwidth of each component. Based on this information, the SFP adjustment can be done based on the policies from network operators as followings: + QoS policies: depending on the service plan of each customer,the new SFP is calculated which takes into account the QoS parameters of that customer. For example, the customer with gold plan will be served by the SFP which consists of SFs, SFFs, and classifiers satisfying the QoS parameters of that gold plan. +---------------------------------------------------------------+ | Policy: "A customer with a Gold service plan" | +------+----------------+----------------+-----------------+----+ | | | | + + + + V V V V +-------------+ +------------+ +------------+ +------------+ |Service | |Service | |Classifier | | Networking | |Function | |Function | | | | subsystem | | | |Forwarder | | | | | |Policy | |Policy | |Policy | | Policy | |translation: | |translation:| |translation:| | Translation| | | | | | | | | |Selected SF | |Selected SFF| |Selected | | Give the | |has low | |has strong | |classifier | | SFP best | |working load | |capacity | |has strong | | latency | |low latency | | | |capacity | | bandwidth | | | | | | | | | | | | | | | | | +-------------+ +------------+ +------------+ +------------+ Figure 2. Policy-based SFP adjustment + Affinity and anti-affinity policies: the new SFP is calculated which takes into account the affinity or anti-affinity policies. For example, when a SF in the SFP fails, the replacement SF should satisfy some anti-affinity policies defined by network operators for achieving the resiliency. That is, the replacement SF and failed SF instances should be located in the different physical hosts or hypervisors or NFVIs. + Traffic engineering and load balancing policies: mentioned in the [ietf-sfc-control-plane] Expires January 7,2017 [Page 5] Internet-Draft Jul 7, 2016 6. Alignment with control plane document This document adds two more use cases for SFP adjustment to the control plane document [ietf-sfc-control-plane] of SFC WG. 7. Security Considerations TBD. 8. IANA Considerations TBD. 9. References 9.1. Normative References [RFC7665] J. Halpern, C. Pignataro, "Service Function Chaining (SFC) architecture", IETF RFC 7665, Oct 2015 9.2. Informative References [ietf-sfc-control-plane] M. Boucadair, "Service Function Chaining (SFC) Control Plane Components & Requirements", draft-ietf-sfc-control-plane-06, May 2016 [irtf-nfvrg-resource-management] Lee, S., Pack, S., Shin, M., and E. Paik, "Resource Management in Service Chaining", draft-irtf-nfvrg- resource-management-service-chain-03, Mar 2016. Expires January 7,2017 [Page 6] Internet-Draft Jul 7, 2016 Authors' Addresses Truong-Xuan Do Soongsil University Changui Bldg. 403, (156-743) 511 Sangdo-Dong, Dongjak-Gu, Seoul, Korea Phone: +82 10 4473 6869 Email: thespring1989@gmail.com Younghan Kim Soongsil University 11F Hyungnam Engineering Bldg. 1107, (156-743) 511 Sangdo-Dong, Dongjak-Gu, Seoul, Korea Phone: +82-2-820-0904 Email: younghak@ssu.ac.kr Expires January 7,2017 [Page 7]