Internet Draft Policy-Based Management MIB March 8, 2000 Policy Based Management MIB draft-ietf-snmpconf-pm-00.txt March 8, 2000 Steve Waldbusser Jon Saperia Thippanna Hongal Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Copyright Notice Copyright (C) The Internet Society (2000). All Rights Reserved. 1. Abstract This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in TCP/IP- based internets. In particular, this MIB defines objects that enable policy-based configuration management of SNMP Various Authors Expires September 8, 2000 [Page 1] Internet Draft Policy-Based Management MIB March 8, 2000 infrastructures. 2. The SNMP Management Framework The SNMP Management Framework presently consists of five major components: o An overall architecture, described in RFC 2571 [1]. o Mechanisms for describing and naming objects and events for the purpose of management. The first version of this Structure of Management Information (SMI) is called SMIv1 and described in STD 16, RFC 1155 [2], STD 16, RFC 1212 [3] and RFC 1215 [4]. The second version, called SMIv2, is described in STD 58, RFC 2578 [5], RFC 2579 [6] and RFC 2580 [7]. o Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in STD 15, RFC 1157 [8]. A second version of the SNMP message protocol, which is not an Internet standards track protocol, is called SNMPv2c and described in RFC 1901 [9] and RFC 1906 [10]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [10], RFC 2572 [11] and RFC 2574 [12]. o Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in STD 15, RFC 1157 [8]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [13]. o A set of fundamental applications described in RFC 2573 [14] and the view-based access control mechanism described in RFC 2575 [15]. A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 [18]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the mechanisms defined in the SMI. Various Authors Expires September 8, 2000 [Page 2] Internet Draft Policy-Based Management MIB March 8, 2000 This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate translations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable information is not considered to change the semantics of the MIB. Various Authors Expires September 8, 2000 [Page 3] Internet Draft Policy-Based Management MIB March 8, 2000 3. Overview Large IT organizations have developed management strategies to cope with the extraordinarily large scale inherent in large networks. In particular, they try to manage the network as a whole by describing and implementing high-level business policies, rather than managing device by device, where orders of magnitude more decisions (and mistakes) may be made. Following this management practice results in the following benefits: - Reduced training needs (fewer details to learn) - Reduced documentation costs (fewer details to document) - Reduced impact of turnover (less ad-hoc knowledge goes out the door) - Greater testability (a greater percentage of fielded configurations may be tested in the lab) - Higher reliability (combination of factors above) - Lower cost of changes (changes can be simpler and operate over a wider extent) - Lower cost of corporate mergers (less knowledge to transfer; fewer policies to integrate) - Lower cost of ownership (combination of factors above) To illustrate the concept of "business policies", some examples are: - All routers will run code version 6.2 - On-site contracters will all have special security restrictions on their ports - All voice over cable ports in California must provide free local calling - Apply special forwarding to all ports whose customers have paid for premium service. Each of these policies could represent an action applied to hundreds of thousands of configuration variables. In order to automate this practice, customers need software tools that will implement business policies across their network, as well as a standard protocol that will ensure that it can be applied to all of their devices, regardless of the vendor. This practice is called Policy-Based Network Management. This document defines standard managed objects for the Simple Network Management Protocol that are used to distribute policies in a standard form throughout the network. Various Authors Expires September 8, 2000 [Page 4] Internet Draft Policy-Based Management MIB March 8, 2000 4. Policy-Based Network Management Architecture Policy-based network management is the practice of applying management operations globally on all managed objects that share certain attributes. Policies always express a notion of: if (an object has certain characteristics) then (apply operation to that object) Policies take the following normal form: if (policyFilter) then (policyAction) A policyFilter is an expression which results in a boolean to determine whether or not an object is a member of a set of objects upon which an action is to be performed. A policyAction is an operation performed on a set of objects. These policies are executed on managed devices, where the objects live (and thus their characteristics may be easily inspected), and where operations on those objects will be performed. A management station is responsible for distributing an organization's policies to all of the managed devices in the infrastructure. The pmPolicyTable provides managed objects for sending a policy to a managed device. In this architecture, the objects that policies act on are called elements. An element is a group of related MIB variables such as all the variables for interface #7. This enables policies to be expressed more efficiently and concisely. Elements can also model circuits, CPUs, queues, processes, systems, etc. The execution model for policies on a managed device is: foreach element for which policyFilter returns true execute policyAction on that element For example: If (interface is fast ethernet) then (apply full-duplex mode) If (interface is access) then (apply security filters) If (gold service paid for on circuit) then (apply special queueing) Various Authors Expires September 8, 2000 [Page 5] Internet Draft Policy-Based Management MIB March 8, 2000 PolicyFilters have the capability of performing comparison operations on SNMP variables, logical expressions, and other functions. Many device characteristics are already defined in MIBs and are easy to include in policyFilter expressions (ifType == ethernet, frCircuitCommittedBurst < 128K, etc). However, there are important characteristics that aren't currently in MIB objects, and worse, it is not current practice to store this information on managed devices. Therefore, this document defines MIB objects for this information. To meet today's needs there are two missing areas: roles and capacity. Roles A role is an abstract characteristic assigned to an element that expresses a notion, such as a political, financial, legal, geographical, or architectural attribute, typically not directly derivable from information stored on the managed system. For example, "paid for premium service" or "is plugged into a UPS" are examples of roles, whereas the percent utilization of a link would not be. The types of information one would put into a role are: political - describes the role of a person or group of people, or of a service that a group of people use. Examples: executive, sales, outside-contracter, customer. If (attached user is executive) then (apply higher bandwidth) If (attached user is outside-contracter) then (restrict access) financial/legal - describes what financial consideration was received. Could also include contractual or legal considerations. Examples: paid, gold, free, trial, demo, lifeline (The lifeline example is supposed to model the RBOC's legal obligation to provide dial tone to elderly/poor). If (gold service paid for) then (apply special queueing) geographical - describes the location of an element. Examples: California, Headquarters, insecure conduit. If (interface leaves the building) then (apply special security) architectural - describes the network architects "intent" for an element. For example: backup, trunk. If (interface is backup) then (set ifAdminStatus = down) Various Authors Expires September 8, 2000 [Page 6] Internet Draft Policy-Based Management MIB March 8, 2000 Collectively, these 4 classes of characteristics are called roles. Roles are human defined strings that can be referenced by a policyFilter. Multiple roles may be assigned to each element. Capabilities Some actions are inappropriate for certain elements or are simply unsupported. PolicyFilter's must be able to be defined so that a policy can be applied only to elements that have the proper capability. The capabilities table provides MIB objects that describe the capabilities of the system. Time Managers may wish to define policies that are true for certain periods of time. This might mean that a policy is downloaded and is dormant for a period of time, becomes active, and then later becomes inactive. Sometimes these time periods will be regular (M-F 9-5) and sometimes ad-hoc. This MIB provides MIB objects that allow policies to be dependent on time. Various Authors Expires September 8, 2000 [Page 7] Internet Draft Policy-Based Management MIB March 8, 2000 5. Definitions pmPolicyEntry OBJECT-TYPE SYNTAX PmPolicyEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry in the policy table. A policy is a pairing of a policyFilter and a policyAction which is used to apply the action to a selected set of objects." INDEX { pmPolicyIndex } ::= { pmPolicyTable 1 } PmPolicyEntry ::= SEQUENCE { pmPolicyIndex Integer32, pmPolicyFilter OCTET STRING, pmPolicyAction TBD, pmPolicyDescription SnmpAdminString, pmPolicyMatches Gauge32, pmPolicyStatus RowStatus } -- roleTable PmRoleESEntry OBJECT-TYPE SYNTAX PmRoleESEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A role string entry associates a role string with an individual element." INDEX { pmRoleESElement, pmRoleESString } ::= { pmRoleESTable 1 } PmRoleESEntry ::= SEQUENCE { pmRoleESElement OBJECT IDENTIFIER, pmRoleESString SnmpAdminString, pmRoleESStatus RowStatus } pmRoleSEEntry OBJECT-TYPE SYNTAX PmRoleSEEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION Various Authors Expires September 8, 2000 [Page 8] Internet Draft Policy-Based Management MIB March 8, 2000 "A role string entry associates a role string with an individual element." INDEX { pmRoleSEString, pmRoleSEElement } ::= { roleSETable 1 } PmRoleSEEntry ::= SEQUENCE { pmRoleSEString SnmpAdminString, pmRoleSEElement OBJECT IDENTIFIER } pmCapabilitiesEntry OBJECT-TYPE SYNTAX PmCapabilitiesEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The capabilities table describes the inherent capabilities of the system." INDEX { pmCapabilitiesIndex } PmCapabilitiesEntry ::= SEQUENCE { pmCapabilitiesIndex Integer32, pmCapabilitiesType OBJECT IDENTIFIER, pmCapabilitiesSubType OBJECT IDENTIFIER } END Various Authors Expires September 8, 2000 [Page 9] Internet Draft Policy-Based Management MIB March 8, 2000 6. Security Considerations There are a number of management objects defined in this MIB that have a MAX-ACCESS clause of read-write and/or read- create. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. SNMPv1 by itself is not a secure environment. Even if the network itself is secure (for example by using IPSec), even then, there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB. It is recommended that the implementors consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model RFC 2574 [12] and the View-based Access Control Model RFC 2575 [15] is recommended. It is then a customer/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them. Various Authors Expires September 8, 2000 [Page 10] Internet Draft Policy-Based Management MIB March 8, 2000 7. References [1] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing SNMP Management Frameworks", RFC 2571, April 1999. [2] Rose, M., and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", STD 16, RFC 1155, May 1990. [3] Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD 16, RFC 1212, March 1991. [4] Rose, M., "A Convention for Defining Traps for use with the SNMP", RFC 1215, March 1991. [5] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [6] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [7] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [8] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple Network Management Protocol", STD 15, RFC 1157, May 1990. [9] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Introduction to Community-based SNMPv2", RFC 1901, January 1996. [10] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1906, January 1996. [11] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", RFC 2572, April 1999. Various Authors Expires September 8, 2000 [Page 11] Internet Draft Policy-Based Management MIB March 8, 2000 [12] Blumenthal, U., and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2574, April 1999. [13] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1905, January 1996. [14] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications", RFC 2573, April 1999. [15] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2575, April 1999. [16] McCloghrie, K. and M. Rose, Editors, "Management Information Base for Network Management of TCP/IP-based internets: MIB-II", STD 17, RFC 1213, Hughes LAN Systems, Performance Systems International, March 1991. [17] McCloghrie, K. and F. Kastenholz, "The Interfaces Group MIB using SMIv2", RFC 2233, Cisco Systems, FTP Software, November 1997. [18] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction to Version 3 of the Internet-standard Network Management Framework", RFC 2570, April 1999. 8. Intellectual Property The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification can be obtained from the IETF Secretariat. Various Authors Expires September 8, 2000 [Page 12] Internet Draft Policy-Based Management MIB March 8, 2000 The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 9. Full Copyright Statement Copyright (C) The Internet Society (2000). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Various Authors Expires September 8, 2000 [Page 13] Internet Draft Policy-Based Management MIB March 8, 2000 Table of Contents 1 Abstract .............................................. 1 2 The SNMP Management Framework ......................... 2 3 Overview .............................................. 4 4 Policy-Based Network Management Architecture .......... 5 5 Definitions ........................................... 8 6 Security Considerations ............................... 10 7 References ............................................ 11 8 Intellectual Property ................................. 12 9 Full Copyright Statement .............................. 13 Various Authors Expires September 8, 2000 [Page 14]