Network Working Group T. Suzuki Internet-Draft Hitachi, Ltd. Intended status: Informational February 14, 2014 Expires: August 18, 2014 Requirements for a Network Disaster Recovery System draft-suzuki-ndrs-requirements-00 Abstract Requirements concerning a network disaster recovery system such as a wide area network management system based on Software Defined Networking (SDN) architecture are presented. Specifically, a multi- layer network management system, which is composed of multiple network layers, layer management functions to manage each network layer, and integrated-layer management, is focused on. The problems that need to be overcome in order to consistently manage dmake the system are presented. The requirements that should be satisfied in order to solve these problems are presented. 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 August 18, 2014. 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 Suzuki Expires August 18, 2014 [Page 1] Internet-Draft Network Disaster Recovery System February 2014 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 . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 4 3. Use Case . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.1. Wide Area Network Disaster Recovery . . . . . . . . . . . 5 3.2. Management System Structure (Type I) . . . . . . . . . . . 5 3.3. Management System Structure (Type II) . . . . . . . . . . 6 4. Requirement . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.1. Requirement for Interface of Type-I System . . . . . . . . 7 4.2. Requirement for Interface of Type-II System . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 7. Informative References . . . . . . . . . . . . . . . . . . . . 10 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 11 Suzuki Expires August 18, 2014 [Page 2] Internet-Draft Network Disaster Recovery System February 2014 1. Introduction This draft describes the requirements that a multi-layer network management system for a disaster recovery should satisfy. An example of the network management system is a Software Defined Networking (SDN) system. Recently, the SDN system has been attracting lots of attention. For example, the SDN system has logically centralized architecture and is expected to make the entire network resource more efficient. In addition, it is also expected to reduce operating cost by creating an automatic network managing function. It is also expected to manage the network to provide high quality data transmission such as low latency and low jitter, or to provide efficient usage of network resource such as bandwidth and so forth. Under the above circumstances, the requirements concerning a network disaster recovery system to manage the network to become highly reliable are described in this draft. The network disaster recovery system is created by controlling multiple network management functions for each network layer in a coordinated manner. Specifically, multi-layer network is managed on the basis of cooperation between the lower-layer network management functions and the upper-layer network management functions. The requirements concerning the multi-layer network management for the network disaster recovery are described here while the requirements for other functions have been discussed in many groups including SDN [SDN] research group. In section 2, specific issues on the multi-layer network management for the network disaster recovery are discussed. In section 3, use cases for a multi-layer network management system are described. In section 4, requirements that the system should satisfy are prescribed. Suzuki Expires August 18, 2014 [Page 3] Internet-Draft Network Disaster Recovery System February 2014 2. Problem Statement One way to create a network disaster recovery system for a network composed of multiple layers is to create a large management function that can control multiple network layers. However, if there is only one network management function or server to manage a large network composed of multiple layers and/or domains, it might become a huge network management object. To avoid such issue, it is better to create a management function for a large scale network by combining multiple network management components. In regard to a conventional network management system, there is a network management function or server for each network layer or domain. Therefore, if multiple network management functions execute their recovery procedures independently, they might be executed inconsistently. For example, if the upper-layer management tries to recover by using routing protocol or policy routing etc. in accordance with an old network topology when the lower-layer management changes the lower-layer topology to recover from a network disaster, the upper-layer data will not be transmitted under the recovered new topology. In this case, the upper-layer management should try to recover in accordance with the new network topology. Therefore, to create a network disaster recovery system for multi- layer network under the conventional conditions, the system has to be created by including multiple management functions for each network layer. In addition, the multiple management functions should cooperate to recover from a network disaster. However, a method or protocol for communication among multiple network management functions for each layer has not been defined yet. Specifically, communication procedures for recovering from a network disaster have not been defined. Suzuki Expires August 18, 2014 [Page 4] Internet-Draft Network Disaster Recovery System February 2014 3. Use Case 3.1. Wide Area Network Disaster Recovery One of use cases for the multi-layer network management system based on the SDN architecture is a wide area network disaster recovery. In case of a network disaster, many network apparatuses are severely damaged and various network services also go down. Therefore, the system has to recover from an out-of-service state by managing the remaing network resources. 3.2. Management System Structure (Type I) A target network disaster recovery system is shown in Figure 1. The system is composed of multiple networks such as an upper-layer network and a lower-layer network, and an upper-layer management server, a lower-layer management server, and an integrated-layer management server. To execute network disaster recovery, multiple network management servers must interact in a coordinated manner. Therefore, as shown in Figure 1, two new interfaces are needed. One is the interface between the integrated-layer network management server and the upper-layer network management server. The other is the interface between the integrated-layer network management server and the lower-layer network management server. +-------------------------------------------------------------+ | Integrated-Layer Network Management Server | +-------------+---------------------------+-------------------+ |(1) New I/F |(2) New I/F +-------------+------------+ | | Upper-Layer Network | | | Management Server | | +-------------+------------+ +-------+-------------------+ | | Lower-Layer Network | | | Management Server | | +-------+-------------------+ |Conventional I/F |Conventional I/F _______|___________________________|_____________ _( ____________________|__ )_ _( _( )_ )_ ( Upper-Layer ( Lower-Layer ) ) (_ Network (_ Network _) _) (_ (________________________) _) (____________________________________________________) Suzuki Expires August 18, 2014 [Page 5] Internet-Draft Network Disaster Recovery System February 2014 Figure 1: Example of a target multi-layer network management system 3.3. Management System Structure (Type II) Another target network disaster recovery system is shown in Figure 2. The system is composed of multiple networks such as an upper-layer network and a lower-layer network, and an upper-layer management server and a lower-layer management server. To execute network disaster recovery, multiple network management servers must interact in a coordinated manner. In this case, as shown in Figure 2, a new interface is needed. It is the interface between the upper-layer network management server and the lower-layer network management server. +-----------------------+ +-----------------------+ | Upper-Layer Network |(3) New I/F | Lower-Layer Network | | Management Server |------------| Management Server | +-------------+---------+ +----+------------------+ | | | | | | |Conventional I/F |Conventional I/F _______|___________________________|_____________ _( ____________________|__ )_ _( _( )_ )_ ( Upper-Layer ( Lower-Layer ) ) (_ Network (_ Network _) _) (_ (________________________) _) (____________________________________________________) Figure 2: Another example of a target multi-layer network management system Suzuki Expires August 18, 2014 [Page 6] Internet-Draft Network Disaster Recovery System February 2014 4. Requirement The interfaces shown in Figure 1 and Figure 2 are needed to create the network disaster recovery system based on the schemes described in the previous section. The requirements for each interface are briefly described below. 4.1. Requirement for Interface of Type-I System (1)Interface between Integrated-layer and Upper-Layer: The first interface is used by the integrated-layer network management server to control the upper-layer network. For example, the integrated-layer network management server controls timing to execute the upper-layer network disaster recovery procedures against the lower-layer network disaster recovery procedures. In addition, the integrated-layer network management server uses the interface to gather information of the lower-layer network conditions such as a topology and provides it to the upper-layer network management server. (2)Interface between Integrated-layer and Lower-Layer: The second interface is used by the integrated-layer network management server to control the lower-layer network. For example, the integrated-layer network management server controls timing to execute the lower-layer network disaster recovery procedures against the upper-layer network disaster recovery procedures. In addition, the integrated-layer network management server uses the interface to gather information of the upper-layer network conditions such as a topology and provides it to the lower-layer network management server. 4.2. Requirement for Interface of Type-II System (3) Interface between Upper-layer and Lower-layer: The third interface is used by the upper-layer network management server and the lower-layer network management server. For example, the lower-layer network management server requests the upper-layer network management server not to start the network disaster recovery procedures while the lower-layer disaster recovery procedures are executed. Suzuki Expires August 18, 2014 [Page 7] Internet-Draft Network Disaster Recovery System February 2014 5. Security Considerations This document describes problems and requirements for a network disaster recovery system. The system might be composed of multiple management functions to manage each network layer and each management function might be implemented in a different computational equipment. To achieve network disaster recovery in a coordinated manner by using multiple management functions, it is necessary to exchange information between them. It is therefore necessary to use a secure communication channel between the management functions. Suzuki Expires August 18, 2014 [Page 8] Internet-Draft Network Disaster Recovery System February 2014 6. IANA Considerations This document includes no request for IANA. Suzuki Expires August 18, 2014 [Page 9] Internet-Draft Network Disaster Recovery System February 2014 7. Informative References [SDN] "SDN Research Group". Suzuki Expires August 18, 2014 [Page 10] Internet-Draft Network Disaster Recovery System February 2014 Author's Address Toshiaki Suzuki Central Research Laboratory, Hitachi, Ltd. 292 Yoshida-cho Totsuka-ku, Yokohama, Kanagawa 244-0817 Japan Phone: +81-50-3135-3066 Email: toshiaki.suzuki.cs@hitachi.com Suzuki Expires August 18, 2014 [Page 11]