NFVRG R. Gu Internet-Draft S. Hu Intended status: Informational China Mobile Expires: September 1, 2017 February 28, 2017 Control and User Plane Seperation Architecture of Cloud based BNG draft-gu-nfvrg-cloud-bng-architecture-00 Abstract This document defines the architecture of Clond-based BNG devices with control plane (CP) and user plane (UP) seperation. Both BNG-CP and BNG-UP are core components for fixed broadband services and deployed seperately at different network layer. 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/. 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 September 1, 2017. Copyright Notice Copyright (c) 2017 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. 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. Gu & Hu Expires September 1, 2017 [Page 1] Internet-Draft Cloud BNG Architecture February 2017 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Definition of terms . . . . . . . . . . . . . . . . . . . . . 2 4. Cloud-based BNG architecture . . . . . . . . . . . . . . . . 3 5. Cloud_BNG use case . . . . . . . . . . . . . . . . . . . . . 4 6. Cloud_BNG related interfaces . . . . . . . . . . . . . . . . 6 7. Security Considerations . . . . . . . . . . . . . . . . . . . 6 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 9. Normative References . . . . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction BNG device is defined as an Ethernet-centric IP edge router, and the aggregation point for the user traffic. It performs Ethernet aggregation and packets forwarding via IP/MPLS, and supports user management, access protocols termination, QoS and policy management, etc. The basic idea of control plane and user plane seperation is to extract and centralize the user management function of multiple BNG devices forming a separate CP, while UP takes function as router CP and BNG forwarding plane. Thus a BNG is constructed of CP and UP which is benefit in cloud-based BNG with the advantages of resource utilization improvement, resource control centralization, new service rapid provision and so on. 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]. 3. Definition of terms AAA:Authentication Authorization Accounting BNG:Broadband Network Gateway CP:Control Plane DHCP:Dynamic Host Configuration Protocol MANO:Management and Orchestration NFV:Network Function Virtualization Gu & Hu Expires September 1, 2017 [Page 2] Internet-Draft Cloud BNG Architecture February 2017 PPPoE:Point to Point Protocol over Ethernet UP: User Plane 4. Cloud-based BNG architecture There are two parts of functions in traditional BNG: one is user access management function, the other is router function. While in cloud-based BNG, we find out that tearing these two functions apart can make a difference. Actually the user management function can be centralized deployed as a concentrated control plane. The reserved functions such as router functi on and forwarding engine can be deployed in the form of user plane. Thus the Cloud-based BNG architecture is made up of control plane and user plane. +------------------------------------------------------------------+ | Neighboring policy and resource management systems | | | | +-------------+ +-----------+ +---------+ +----------+ | | |Radius Server| |DHCP Server| | EMS | | MANO | | | +-------------+ +-----------+ +---------+ +----------+ | +------------------------------------------------------------------+ +------------------------------------------------------------------+ | CU-separated BNG system | | +--------------------------------------------------------------+ | | |+----------+ +---+ +----------+ +------++------++-----------+ | | | || Address | |AAA| |Subscriber| |Radius||PPPoE/|| UP | | | | ||management| | | |management| | ||IPoE ||management | | | | |+----------+ +---+ +----------+ +------++------++-----------+ | | | | CP | | | +--------------------------------------------------------------+ | | +---------------------------+ +--------------------------+ | | | +------------------+ | | +------------------+ | | | | | Routing control | | | | Routing control | | | | | +------------------+ | ... | +------------------+ | | | | +------------------+ | | +------------------+ | | | | |Forwarding engine | | | |Forwarding engine | | | | | +------------------+ UP | | +------------------+ UP| | | +---------------------------+ +--------------------------+ | +------------------------------------------------------------------+ Figure 1: Architecture of C/U Seperation BNG The CP is a user control management component that supports (1)address management:unified address pool management Gu & Hu Expires September 1, 2017 [Page 3] Internet-Draft Cloud BNG Architecture February 2017 (2)AAA and RADIUS:cooperation with the RADIUS server and others to implement AAA for access users (3)Subscriber management:user entry management and forwarding policy management (4)PPPoE/IPoE:process user dialup packets of PPPoE/IPoE (5)UP management:management of UP interface status, and the setup, deletion, maintenance of channels between CP and UP The UP is a network edge and user policy implementation component, including (1)Control plane functions including routing, multicast, and MPLS (2)forwarding plane functions including traffic forwarding, QoS, and traffic statistics collection (3)Other functions such as configuration of routing services through EMS Cooperation with the DHCP server or use of the local Neighboring policy and resource management systems deploys different service systems such as RADIUS server, DHCP server and EMS. Besides NFV infrastructure management system MANO is included in resource mangement systems. All of them have connections with BNG CP. 5. Cloud_BNG use case In the next generation of Telecom Integrated Cloud (TIC) focusing on content and traffic instead of voice, there can be several layers which we call core TIC layer and edge TIC layer. Core TIC layer: mainly responsible for control, management, and scheduling functions and carries control-plane NE, centralized media- plane NE, CDN device, and backbone network traffic. BNG-CP is deployed in this layer. Edge TIC layer: oriented towards major media planes and is mainly responsible for terminating media traffic. BNG-CP is deployed in this layer. Gu & Hu Expires September 1, 2017 [Page 4] Internet-Draft Cloud BNG Architecture February 2017 ---------------- ///--- ---\\\ //// \\\\ /// +--------------------------------+ \\\ // | Orchestrator | \\ | +--------------------------------+ | | | |+----------------+ +-------+ | || SDN CONTROLLER | | CSCF | | |+----------------+ +-------+ | | | | ********** +-------+ +-------+ | \\ * BNG CP * | MME | | 5G CP | // \\\ ********** +-------+ +-------+ /// \\\\ //// \\\--- ---/// CORE TIC LAYER ---------------- +-------+ | 5G UP | +-------+ ----- ----- ----- ///- -\\\ ///- -\\\ //- -\\\ / ********* \ / +-------+ \ / \ | *BNG UP* | | | SBC | | | | | ********* | | +-------+ | | +-------+ | | +-------+ | | +-------+ | | | CDN | | | | S-CPE | | | | GW | | | +-------+ | \ +-------+ / \ +-------+ / \ / \\\- -/// \\\- -/// \\\- -/// ----- ----- ----- Fixed network Mobile network Content media plane media plane media plane EDGE TIC LAYER Figure 2: C/U Seperation BNG USE CASE In the Core TIC layer, BNG CP is deployed including the BNG Service and Subscriber Session Control function which could be virtualized and centralized. The functional components inside the BNG Service and Subscriber Session Control can be implemented as VNFs and run in x86 servers. In the Edge TIC layer, the routing and forwarding parts could be distributed as BNG UP. Due to high packet processing performance requirements, BNG UP can remain as physical devices. If it's in some Gu & Hu Expires September 1, 2017 [Page 5] Internet-Draft Cloud BNG Architecture February 2017 practical situation, the number of subscribers is relatively small, the BNG UP can be virtualized as well. 6. Cloud_BNG related interfaces TBD. 7. Security Considerations None. 8. IANA Considerations None. 9. 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, . [RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, DOI 10.17487/RFC2234, November 1997, . Authors' Addresses Rong Gu China Mobile 32 Xuanwumen West Ave, Xicheng District Beijing, Beijing 100053 China Email: gurong_cmcc@outlook.com Shujun Hu China Mobile 32 Xuanwumen West Ave, Xicheng District Beijing, Beijing 100053 China Email: hushujun@chinamobile.com.com Gu & Hu Expires September 1, 2017 [Page 6]