HTTP/1.1 200 OK Date: Mon, 08 Apr 2002 22:54:48 GMT Server: Apache/1.3.20 (Unix) Last-Modified: Tue, 17 Mar 1998 16:31:00 GMT ETag: "2e7e17-8214-350ea544" Accept-Ranges: bytes Content-Length: 33300 Connection: close Content-Type: text/plain INTERNET-DRAFT Networking Working Group Gerhard Bogler Internet Draft Siemens AG Expires January 16, 1998 Internet Technology for Integration of Carrier Network Management (TMN) and Enterprise Network Management Status of this Memo This document is an Internet-Draft. 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.'' To learn the current status of any Internet-Draft, please check the ``1id-abstracts.txt'' listing contained in the Internet-Drafts Shadow Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe), munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or ftp.isi.edu (US West Coast). This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Abstract The complexity of telecommunication networks, i.e. enterprise and carrier networks, has grown over the last two decades. Management of carrier networks and enterprise networks has followed different paradigms up to now: - In carrier networks the Telecommunications Management Network (TMN) as created by ITU-T in the early 1980s is still being propagated. - In enterprise networks the SNMP based approach is widely accepted. The borders between public (carrier) and private (enterprise) networks are becoming increasingly transparent, a distinction between both types of networks may soon be irrelevant from a network management point of view. Expires January 16, 1998 Page 1 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 In the light of this development an integrating framework for network management can be expected to gain rapid importance. This Internet Draft shows that Internet technology and existing IETF standards supplemented by a quite limited set of additional specifica- tions can be used as the basis for a cooperative network management approach, integrating management of both network management worlds while leaving their interior essentially untouched. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Existing Management Frameworks . . . . . . . . . . . . . . . . . 3 3. Basic Requirements for a Framework for Integrated Network Management . . . . . . . . . . . . . . . . . . . . . . . 6 4. Framework Architecture . . . . . . . . . . . . . . . . . . . . . 8 5. Areas for Work in the IETF . . . . . . . . . . . . . . . . . . .13 6. Security Considerations . . . . . . . . . . . . . . . . . . . .15 7. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . .15 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . .15 9. Author's Address . . . . . . . . . . . . . . . . . . . . . . . .16 1. Introduction 1.1 Motivation: the Challenge for Integrated Network Management Today, enterprise and carrier networks are converging. The discrimina- tion between enterprise and carrier networks, between IT and telecommuni- cation is fading. Some consequences for network management are: - De-regulation in many countries allows organizations to be customers (users) of a network as well as providers of a service. Network management is shared among many parties: the "classical" network operator ('Telco'), the value-adding service provider, the ISP, the enterprise network user operating an own network, brokers/resellers of network services etc. - There is a need to integrate management for different types of nodes as the underlying technologies are being more and more integrated. Examples include but are not limited to: IP over ATM, MPOA (Multiprotocol over ATM, standardized by the ATM-Forum), ATM over SDH/Sonet. - Some technologies which are commonly used in enterprise and carrier networks, e.g. ATM, require integrated management. Note that ATM nodes in carrier networks are managed using MIBs according to ATM Forum specifications (M4) or ITU-T Recommendations (I.751) while ATM nodes in enterprise networks are managed using e.g. the AToM MIB of the IETF (RFC 1695). Expires January 16, 1998 Page 2 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 - Virtual Private Networks (VPNs) using "public" network resources require cooperation between enterprise and carrier network management. VPN owners need to manage their dedicated resources in the carrier network. In a nutshell, the challenge that the progressing convergence of networks presents is to manage several network management worlds (SNMP, CMIP and existing proprietary solutions) in a consistent way while preserving the vast investments in existing networks and network management solutions. This Internet Draft shows that while much of the needed technology and the standards are already in place, some additional standardization efforts will be needed to create a common framework for enterprise and carrier network management. 1.2 Scope This Internet-Draft does NOT intend to - contribute to the discussion about pro's and con's of SNMP and CMIP, - propose any concept to replace existing SNMP and CMIP based solutions, - define a new management protocol and a new management scheme. Instead, this Internet-Draft - is intended to initiate work on the integration of the traditionally separated network management for enterprise networks and carrier networks. - identifies basic requirements and introduces functional entities which enhance the current management architectures, - proposes areas of work to be tackled by the IETF in order to support the requirements. 2 Existing Management Frameworks Network management for carrier and enterprise networks has been traditionally separated: TMN framework vs. SNMP/SMI framework. 2.1 The TMN Framework In the 1980s, the vision was established to monitor and tune all types of telecommunication network, usually without any manual intervention. In 1988, the International Telecommunications Union (formerly CCITT) was the first to define formally the concept of Telecommunications Management Networks [7]. Expires January 16, 1998 Page 3 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 The TMN concept relies on 3 pillars: - its functional architecture (which may be mapped in various ways to concrete physical configurations), - its Logical Layered Architecture (LLA) and - its standardized interfaces. 2.1.1 The TMN Functional Architecture TMN according to ITU-T Rec. M.3010 identifies 3 main function blocks: - Operations Systems Function (OSF) block: The OSF processes management information for the purpose of monitoring/coordinating and/or controlling telecommunication functions. - Network Element Function (NEF) block: The NEF is a functional block which communicates with the TMN for the purpose of being monitored and/or controlled. The NEF is the characterizing part of the Network Elements, such as switches. - Q-Adapter Function (QAF) block: The QAF is used to connect non-TMN entities, i.e. entities with non-TMN interfaces. It should be noted that from a TMN's point of view SNMP-based Network Elements would have to interact with a TMN via a QAF. The TMN function blocks interact accross TMN reference points. 2.1.2 The TMN Logical Layered Architecture (LLA) Management functions in the TMN, i.e. the TMN OSFs, have been organized in 4 layers defining the so called Logical Layered Architecture (LLA) of the TMN. The layers are: - Element management layer (EML): The EML manages each network element on an individual basis and supports an abstraction of the functions provided by the NE layer. - Network management layer (NML): the NML has the responsibility for the management of all the NEs, as presented by the EML, both individually and as a set. It is not concerned with how a particular element provides services internally. - Service management layer (SML): Service management is concerned with, and responsible for, the contractual aspects of services that are being provided to customers or are being made available to potential new customers. Expires January 16, 1998 Page 4 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 - Business management layer (BML): The business management layer has responsibility for the total enterprise and is the layer at which agreements between network operators are made. 2.1.3 The TMN Interfaces In order to achieve interoperability between management systems (in TMN terms Operations Systems = OS) and managed systems, respectively, between two management systems, TMN defines standardized interfaces (see [9]). The TMN interfaces are the realization of the TMN reference points. The most prominent ones are: - The Q3 interface is the interface between management systems and network elements of one network operator (corresponding to the q3 reference point in the TMN functional architecture shown in Figure 1). Q3 has been the main focus of TMN standarization up to now. - The X interface is the interface between management systems of different network operators (carrier or enterprise networks). As basis for the TMN interfaces, the OSI systems management technology was chosen, a set of standards developed jointly by the International Standards Organization (ISO) and ITU. According to ITU-T Rec. M.3010, TMN interfaces consist of a communications protocol stack, defined in ITU-T Recommendations Q.811 and Q.812 [9] with the CMIP protocol on top [8] and an information model specified according to ITU-T Recs. X.722 (Guide to the Definition of Managed Objects [10]). TMN interfaces have been deployed in a number of carrier networks. In enterprise networks, TMN interfaces have had virtually no influence up to now. 2.2 The SNMP/SMI Framework Management of modern enterprise networks is dominantly based on Internet standards. SNMP version 1 (SNMPv1) is the original Internet-standard Network Management Framework. It consists of these three documents: - RFC 1157 [1] defines the Simple Network Management Protocol (SNMP), the protocol used for network access to managed objects. Expires January 16, 1998 Page 5 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 - RFC 1155 [2] defines the Structure of Management Information (SMI), the mechanisms used for describing and naming objects for the purpose of management. - RFC 1212 [3] defines a more concise description mechanism which is wholly consistent with the SMI. Currently, SNMP is being progressed by the IETF towards SNMP v3. 3. Basic Requirements for a Framework for Integrated Network Management Two types of basic requirements can be identified: operational requirements stating the goals, i.e. what shall be achieved by this management framework, and technology requirements stating which technology is best suited to achieve these goals. 3.1 Key Operational Requirements The network management framework shall support - end-to-end management. This requirement addresses the need to cooperate with more than one network element to perform complex management tasks at the higher management layers, i.e. above element management. An example is the creation of an ATM virtual circuit or a SONET path. - integrated management across multiple network technologies. This requirement addresses the need to jointly manage network elements of different technologies. An example is coordinated management of IP routers and ATM switches. - cooperation between several (human) operators, management applications and managed systems. This requirement acknowledges the fact that management in modern networks is shared among many parties. Examples include: management of ATM end-to-end accross the boundaries of network operators' domains or coordinated provisioning of services involving various departments of a service provider's organization (e.g. customer care and switch managements, billing department etc.). - network user access to network management in a 'public' operator's domain. This capability is generally known as Customer Network Management (CNM). This requirement addresses the trend that, in particular, operators of enterprise networks require direct control of their subscribed services and network resources in a carrier's network. Expires January 16, 1998 Page 6 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 An example is management of a Virtual Private Network (VPN) by a corporate user of the carrier network. - interworking with existing and new SNMP and CMIP based management systems. The framework shall allow also for interworking with proprietary management systems. This requirement addresses the fact that huge investments have been made by enterprise and carrier network operators in their infra- structures. Any management framework which proposed to replace existing solutions, e.g. by introducing a new management protocol between management systems and Network Elements is most probably bound to fail. 3.2 Technology Requirements The network management framework shall support - a WWW-style user interface. Off-the shelf WWW-browsers shall be used in the management stations. This requirement addresses the fact that the user interfaces provided by WWW browsers have received wide acceptance and can be seen as state-of-the-art for user interfaces to server-based information services. - a common representation of management procedures, operations and information elements of different styles and formats. This requirement addresses the need to provide the operator with one common view of the items he is handling. That means he should be able to work at a service (= management task) level view which integrates or at least hides details of network resource. Another requirement is to integrate management related information resources, e.g. operation manuals and training/tutorial information. - flexible linking of the entities listed above by hyperlinks as used in the WWW. This requirement is a consequence from the need to support the variety of end-to-end operational procedures, network management task steps etc. A browser-based user interface is used to present the various elements making up integrated network management to the operator. - customization of this linked HTML structure via the network operators management stations and also across a CNM interface. This requirement addresses the fact that in practice network management is highly network operator specific. Basic management operations are combined in very specific ways to fit into the respective organization of a network operator. Obviously this is also true for enterprise network users. Therefore the requirement for customization capabilities holds also for a CNM interface. Expires January 16, 1998 Page 7 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 - interfaces to existing management systems (SNMP and CMIP based, and proprietary). This requirement is a consequence from the need to cooperate with existing management systems especially at the element management layer. - the mapping of linked HTML structures to sets/sequences of SNMP/CMIP (or proprietary) operations. This requirement is a consequence from the fact that from the operator's point of view network management tasks, operations and information elements are represented by a WWW-like structure while interaction with existing management systems has to use existing protocols and data structures. - linking of network originating events (traps in SNMP, event notifications in CMIP) to the relevant pages in the SIB. This requirement addresses the need for the network operator to get knowledge of, and react to, events in the managed network. Examples include major outages of network resources, overload of nodes and transport systems. 4. Framework Architecture 4.1 Building Blocks This section proposes three architectural enhancements to the existing management frameworks which address the requirements in the previous section: - the use of WWW technology for representing management tasks - the introduction of cooperative sessions for network management - the interworking with SNMP based, CMIP based and proprietary management systems. The principal architectural entities which are introduced are: - CSC Cooperative Session Control - SIB Server Information Base - GAP Gateway Application Figure 1 gives an overview. For the sake of simplicity standard components are not shown such as the WWW-server function and the SNMP respectively CMIP protocol machines for communication with existing management systems. Expires January 16, 1998 Page 8 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 -- -- | | management stations | | -- (using WWW browsers) -- / \ / \ ---- +-----------------+ ---- | | | | +----------+ Inter/Intranet +----------+ | | -- +---+---------+---+ | | | | -- SIB +-----+---------+------+ \ / \ customiz. | ----- ----- | | ---- interface | | CSC |-----| SIB | | | +--------------+ ----- ----- | | +-+---------+--------+-+ > Management | | | | Server +-+--+ +-+--+ +-+--+ | |GAP | |GAP | |GAP | | +-+--+ +-+--+ +-+--+ / | | | +----------+ +----+-----+ +----------+ |Mgmt.syst.| |Mgmt.syst.| |Mgmt.syst.| |e.g. SNM | |e.g. CM | |e.g. propr| +----+-----+ +----+-----+ +-----+----+ | | | +--+-+ +--+-+ +-+--+ Network | NE | | NE | | NE | Elements +----+ +----+ +----+ e.g. router, bridge e.g. carrier switch e.g. transm. equipm. Figure 1: Architectural Entities for WWW-based network management The principal functional entities are characterized as follows: - Cooperative Session Control Function (CSC) The CSC controls the multi-party sessions. It handles adding and removing of session participants which can be humans (e.g. operator staff) and applications (e.g. in existing management systems). The CSC uses information represented by so-called cooperation task descriptions which are represented by linked HTML pages. - Server Information Base (SIB) The server information base is the repository of entities required for WWW-based, cooperative, multi-technology, end-to-end management. It contains the following types of entities: Expires January 16, 1998 Page 9 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 - Managed entities representing the resources to be managed; this includes also resources in the management server - management task descriptions - elementary management operations - information entities (help texts, multimedia guidance etc.) - processing entities, i.e. pieces of code representing management logic relating to one or more of the entities above, e.g. the mapping of a management task to a set of management operations, or the mapping of an elementary operation to an SNMP operation etc. - event-related entities, i.e. stored event notifications (spontaneously emitted in the case of CMIP, retrieved by polling in the case of SNMP) All these entities are represented to the operator by WWW-type pages connected by hyperlinks. - Gateway Applications (GAP) The management server makes use of Gateway Application (GAP) to cooperate with existing (and new) management systems, i.e. for sending commands and receiving event information. The GAPs include the conversion of management commands and event messages to/from WWW representation (HTTP/HTML) and handle access authorization to existing management systems. GAPs can be used to adapt to management systems based on standard MIBs (SNMP or CMIP) or to proprietary management systems. It should be noted that this adaptation does not necessarily need to cover the complete functionality of the respective element management systems. 4.2 External Interfaces Internal interfaces, i.e. interfaces within the management server such as the interface between CSC and SIB (see Fig. 1), are outside the scope of this Internet Draft. (1) Interface: Management Station (operator or user domain) - Management Server This shall be a WWW-type interface (HTTP). Expires January 16, 1998 Page 10 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 (2) Interface: Management Server - existing/new element management systems The communication mechanisms for this interface are determined by the corresponding management system, i.e. SNMP or CMIP (or proprietary). (3) Interface: SIB Customization This shall be a WWW-type interface. This interface allows the operator staff to customize the Server Information Base. The corresponding MIB (SIB MIB) is described using the SNMP framework. This SIB MIB is proposed as a subject for further study. 4.3 Principles of the Server Information Base (SIB) The SIB consists of a linked structure of WWW-type pages. The operator performs management tasks by surfing this linked WWW structure. He follows hyperlinks which lead to management task descriptions and operation forms (corresponding to elementary management operations) to be filled in. Concrete management interaction with an existing EM/NM (element management/network management) system is implicitly invoked by clicking at the corresponding hyperlink. Data and operation results received from an element management system at one step of a management task can be passed to subsequent steps of the management task by following predefined hyperlinks. The operator can view alarm messages originating from the network by selecting corresponding WWW pages. The operator can access multimedia guidance information ("help", represented as WWW pages) in any phase of a management task. Gateway applications are responsible for interworking with the existing element managers. This includes coordination of these interactions. An example may illustrate these principles: A member of an operator's staff accesses network management functionality by entering the URL designated for end-to-end management. This causes a start page to pop up. Expires January 16, 1998 Page 11 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 Let's assume that the staff member intends to create an ATM PVC (Permanent Virtual Circuit). By following the appropriate hyperlinks he will finally arrive at a task description page titled 'Create an ATM PVC'. At this point the staff member has several options: - to enter immediately the requested information for creating the ATM PVC, e.g. Quality of Service (QoS) parameters, identification of the respective end points in the network elements etc. - to ask for further information about the task, i.e. request a description of the procedure 'how to create an ATM PVC' or request information about syntax and/or semantics of a specific parameter, e.g. QoS. - to request information about availability, current status etc. of the network resources required for that task. - to request another human operator or management to join the management session; an example may be to query the account status of the future owner of the ATM PVC being provisioned. The staff member can choose between these options by selecting the appropriate hyperlink. He is guided through the whole management task step by step, being offered only those hyperlinks which are relevant depending on the status of the task. After providing all the information needed to create the ATM PVC, execution of the single elementary operations which make up the task is triggered in the respective element management systems. These element management systems perform the necessary actions on the network elements in their respective domains. The responses of the element managers are collected, corresponding HTML pages are created and stored in the SIB. A summary response page is generated and stored in the SIB. Finally the staff member who has initiated the management task is informed about completion of this task. Expires January 16, 1998 Page 12 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 5. Areas for Work in the IETF 5.1 What is Already in Place, or Currently under Work? The majority of the needed technology and standards is already in place: Transport Protocols: IETF: IP, TCP, UDP, HTTP ISO/ITU-T: OSI layers 1-6, layer 7 association control (ACSE) No additional standardization effort is necessary in this area. Management Protocols/MIBs: IETF: SNMP, SMI, many equipment specific MIBs ISO/ITU-T: CMIP, GDMO, several application specific MIBs SNMP version 3 is currently under work. No additional standardization efforts in the management protocol area are proposed in this Internet draft. MIB efforts are proposed in section 5.2. User Interfaces: IETF: HTML and add-ons No additional standardization efforts in the user interface area are proposed in this Internet draft. 5.2 What Needs Still to Be Done? In order to fulfill the requirements for integrated network management some additions to the existing technology/standards are proposed: Framework: Work is proposed to determine and detail the functional entities and their principal interaction needed for cooperative, WWW based network management. This framework should also cover security aspects. Expires January 16, 1998 page 13 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 Multi-party Sessions: Work is proposed to investigate usability of protocols defined by the mmusic-group (Session Initiation Protocol; Session Description Protocol) for network management. MIBs: Work is proposed for creating a SIB MIB for managing the Server Information Base (SIB). This 'SIB MIB' shall be used by the network operator and (parts of it) also by selected users via a CNM interface. The SIB MIB shall cover managed objects representing: - management tasks - elementary management operations (which are mapped by GAPs to SNMP or CMIP operations) - information entities (e.g. help texts, multimedia guidance information etc.) - processing entities, i.e. software components performing a specific task, such as plausibility checks etc. - grouping entities of the SIB to new complex SIB entities - linking entities of the SIB - network originating events - managed objects representing supporting entities (e.g. event logs) Mapping (GAPs): Work is proposed to investigate the rules for mapping between the linked HTML structure of the SIB and the elementary management operations determined by the cooperating management systems (SNMP, CMIP). An initial proposal addressing this topic was submitted in 11/96 as an Internet Draft (in the meantime deleted). What kind of RFCs should be created? The output of this activity could be structured as follows: Expires January 16, 1998 Page 14 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 RFC 'Requirements and Framework': requirements and framework architecture of WWW-based integrated network management (scope: roughly characterized by the contents of sections 2 and 3 of this Internet draft). This should include also security aspects of integrated network management. RFC 'Mapping': mapping management tasks (procedures), management elementary operations, text and multimedia information to URLs (design a scheme which allows to represent and address the various entities which make up network management using WWW techniques). RFC 'SIB MIB': A 'Customizing MIB' for the support of management of the server information base. This MIB shall support creating, deleting and modifying management tasks and other entities of the SIB. A further RFC which may be created (depending on the usability of IP session protocol for cooperative network management): RFC 'CSC': This RFC could cover the application and management of a multi-party session control for network management. This includes a 'session control MIB'. 6. Security Considerations Security considerations are not discussed in this initial draft. 7. Acknowledgments The author is indebted for valuable comments from Reinhard Scholl and Max Sevcik. 8. References [1] J. Case, M.Fedor, M. Schoffstall and C. Davin, "The Simple Network Management Protocol (SNMP)", RFC 1157, May 1990 [2] M. Rose, K. McCloghrie,"Structure and Identification of Management Information for TCP/IP-based Internets", RFC 1155, May 1990 [3] M. Rose, K. McCloghrie, "Concise MIB Definitions", RFC 1212, March 1991 Expires January 16, 1998 Page 15 Internet Draft Internet Tech. for Integr. of Netw.Mgmt. July 16, 1997 [4] T. Berners-Lee, R. Fielding and H. Frystyck, "Hypertext Transfer Protocol, HTTP/1.0", RFC 1945, May 1996, [5] T. Berners-Lee, D. Connolly: "Hypertext Markup Language 2.0", RFC 1866, November 1995. [6] T. Berners-Lee, L. Masinter, M. McCahill, "Uniform Resource Locators (URL)", RFC 1738, December 1994. [7] ITU-T: Recommendation M.3010 "Principles for a Telecommunications Management Network", [8] ISO/IEC, ITU-T, Information Technology - OSI, Common Management Information Protocol (CMIP) - Part 1: Specification ISO/IEC 9596-1, ITU-T Recommendation X.711 [9] ITU-T, Lower Layer Protocol Profiles for the Q3 Interface, Recommendation Q.811 Higher Layer Protocol Profiles for the Q3 Interface, Recommendation Q.812 [10] ISO/IEC, ITU-T, Information Technology - OSI, Guidelines for the Definition of Managed Objects, Recommendation X.722 [11] ITU-T, Asynchronous Transfer Mode (ATM) Management of the Network Element View, Recommendation I.751 [12] ATM Forum, M4 Interface Requirements and Logical MIB: ATM Network Element View, af-nm-0020.000, October 1994 ATR Forum, CMIP Specification for the M4 Interface, af-nm-0027.001, September 1995 [13] M. Ahmed, K. Tesink, IETF, "Definition of Managed Objects for ATM Management version 8.0 using SMIv2, RFC 1695 9. Author's Address Gerhard Bogler Siemens AG, Hofmannstrasse 51, D-81359 Munich, Germany tel.: +49-89-722 27685, fax: +49-89-722 23528, gerhard.bogler@oen.siemens.de Expires January 16, 1998 Page 16