RFC3535 Overview of the 2002 IAB Network Management Workshop

3535 Overview of the 2002 IAB Network Management Workshop. J.Schoenwaelder. May 2003. (Format: TXT=42566 bytes) (Status: INFORMATIONAL)

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Network Working Group                                   J. Schoenwaelder
Request for Comments: 3535               International University Bremen
Category: Informational                                         May 2003


          Overview of the 2002 IAB Network Management Workshop

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2003).  All Rights Reserved.

Abstract

   This document provides an overview of a workshop held by the Internet
   Architecture Board (IAB) on Network Management.  The workshop was
   hosted by CNRI in Reston, VA, USA on June 4 thru June 6, 2002.  The
   goal of the workshop was to continue the important dialog started
   between network operators and protocol developers, and to guide the
   IETFs focus on future work regarding network management.  This report
   summarizes the discussions and lists the conclusions and
   recommendations to the Internet Engineering Task Force (IETF)
   community.























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Table of Contents

   1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  2
   2. Network Management Technologies  . . . . . . . . . . . . . . .  3
        2.1 SNMP / SMI / MIBs  . . . . . . . . . . . . . . . . . . .  4
        2.2 COPS-PR / SPPI / PIBs  . . . . . . . . . . . . . . . . .  5
        2.3 CIM / MOF / UML / PCIM . . . . . . . . . . . . . . . . .  6
        2.4 CLI / TELNET / SSH . . . . . . . . . . . . . . . . . . .  7
        2.5 HTTP / HTML  . . . . . . . . . . . . . . . . . . . . . .  8
        2.6 XML  . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   3. Operator Requirements  . . . . . . . . . . . . . . . . . . . . 10
   4. SNMP Framework Discussions . . . . . . . . . . . . . . . . . . 12
   5. Consolidated Observations  . . . . . . . . . . . . . . . . . . 14
   6. Recommendations  . . . . . . . . . . . . . . . . . . . . . . . 16
   7. Security Considerations  . . . . . . . . . . . . . . . . . . . 17
   8. Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 17
   Normative References  . . . . . . . . . . . . . . . . . . . . . . 18
   Informative References  . . . . . . . . . . . . . . . . . . . . . 18
   Appendix - Participants . . . . . . . . . . . . . . . . . . . . . 19
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . . 19
   Full Copyright Statement  . . . . . . . . . . . . . . . . . . . . 20

1. Introduction

   The IETF has started several activities in the operations and
   management area to develop technologies and standards that aim to
   help network operators manage their networks.  The main network
   management technologies currently being developed within the IETF
   are:

   o  The Simple Network Management Protocol (SNMP) [RFC3410] was
      created in the late 1980s.  The initial version (SNMPv1) is widely
      deployed, while the latest version (SNMPv3), which addresses
      security requirements, is just beginning to gain significant
      deployment.

   o  The Common Information Model (CIM) [CIM], developed by the
      Distributed Management Task Force (DMTF), has been extended in
      cooperation with the DMTF to describe high-level policies as rule
      sets (PCIM) [RFC3060].  Mappings of the CIM policy extensions to
      LDAP schemas have been defined and work continues to define
      specific schema extension for QoS and security policies.

   o  The Common Open Policy Service (COPS) [RFC2748] protocol has been
      extended to provision configuration information on devices (COPS-
      PR) [RFC3084].  Work is underway to define data definitions for
      specific services such as Differentiated Services (DiffServ).




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   During 2001, several meetings have been organized at various events
   (NANOG-22 May 2001, RIPE-40 October 2001, LISA-XV December 2001,
   IETF-52 December 2001) to start a direct dialog between network
   operators and protocol developers.  During these meetings, several
   operators have expressed their opinion that the developments in the
   IETF do not really address their requirements, especially for
   configuration management.  This naturally leads to the question of
   whether the IETF should refocus resources, and which strategic future
   activities in the operations and management area should be started.

   The Internet Architecture Board (IAB), on June 4 thru June 6, 2002,
   held an invitational workshop on network management.  The goal of the
   workshop was to continue the important dialog started between network
   operators and protocol developers, and to guide the IETFs focus on
   future work regarding network management.

   The workshop started with two breakout session to (a) identify a list
   of technologies relevant for network management together with their
   strengths and weaknesses, and to (b) identify the most important
   operator needs.  The results of these discussions are documented in
   Section 2 and Section 3.  During the following discussions, many more
   specific characteristics of the current SNMP framework were
   identified.  These discussions are documented in Section 4.  Section
   5 defines a combined feature list that was developed during the
   discussions following the breakout sessions.  Section 6 gives
   concrete recommendations to the IETF.

   The following text makes no explicit distinction between different
   versions of SNMP.  For the majority of the SNMP related statements,
   the protocol version is irrelevant.  Nevertheless, some statements
   are more applicable to SNMPv1/SNMPv2c environments, while other
   statements (especially those concerned with security) are more
   applicable to SNMPv3 environments.

2. Network Management Technologies

   During the breakout sessions, the protocol developers assembled a
   list of the various network management technologies that are
   available or under active development.  For each technology, a list
   of strong (+) and weak (-) points were identified.  There are also
   some characteristics which appear to be neutral (o).

   The list does not attempt to be complete.  Focus was given to IETF
   specific technologies (SNMP, COPS-PR, PCIM) and widely used
   proprietary technologies (CLI, HTTP/HTML, XML).  The existence of
   other generic management technologies (such as TL1, CORBA, CMIP/GDMO,





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   TMN) or specific management technologies for specific problem domains
   (such as RADIUS, DHCP, BGP, OSPF) were acknowledged, but were not the
   focus of discussion.

2.1 SNMP / SMI / MIBs

   The SNMP management technology was created in the late 1980s and has
   since been widely implemented and deployed in the Internet.  There is
   lots of implementational and operational experience, and the
   characteristics of the technology are thus well understood.

   +  SNMP works reasonably well for device monitoring.  The stateless
      nature of SNMP is useful for statistical and status polling.

   +  SNMP is widely deployed for basic monitoring.  Some core MIB
      modules, such as the IF-MIB [RFC2863], are implemented on most
      networking devices.

   +  There are many well defined proprietary MIB modules developed by
      network device vendors to support their management products.

   +  SNMP is an important data source for systems that do event
      correlation, alarm detection, and root cause analysis.

   o  SNMP requires applications to be useful.  SNMP was, from its early
      days, designed as a programmatic interface between management
      applications and devices.  As such, using SNMP without management
      applications or smart tools appears to be more complicated.

   o  Standardized MIB modules often lack writable MIB objects which can
      be used for configuration, and this leads to a situation where the
      interesting writable objects exist in proprietary MIB modules.

   -  There are scaling problems with regard to the number of objects in
      a device.  While SNMP provides reasonable performance for the
      retrieval of a small amount of data from many devices, it becomes
      rather slow when retrieving large amounts of data (such as routing
      tables) from a few devices.

   -  There is too little deployment of writable MIB modules.  While
      there are some notable exceptions in areas, such as cable modems
      where writable MIB modules are essential, it appears that router
      equipment is usually not fully configurable via SNMP.

   -  The SNMP transactional model and the protocol constraints make it
      more complex to implement MIBs, as compared to the implementation
      of commands of a command line interface interpreter.  A logical
      operation on a MIB can turn into a sequence of SNMP interactions



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      where the implementation has to maintain state until the operation
      is complete, or until a failure has been determined.  In case of a
      failure, a robust implementation must be smart enough to roll the
      device back into a consistent state.

   -  SNMP does not support easy retrieval and playback of
      configurations.  One part of the problem is that it is not easy to
      identify configuration objects.  Another part of the problem is
      that the naming system is very specific and physical device
      reconfigurations can thus break the capability to play back a
      previous configuration.

   -  There is often a semantic mismatch between the task-oriented view
      of the world usually preferred by operators and the data-centric
      view of the world provided by SNMP.  Mapping from a task-oriented
      view to the data-centric view often requires some non-trivial code
      on the management application side.

   -  Several standardized MIB modules lack a description of high-level
      procedures.  It is often not obvious from reading the MIB modules
      how certain high-level tasks are accomplished, which leads to
      several different ways to achieve the same goal, which increases
      costs and hinders interoperability.

   A more detailed discussion about the SNMP management technology can
   be found in Section 4.

2.2 COPS-PR / SPPI / PIBs

   The COPS protocol [RFC2748] was defined in the late 1990s to support
   policy control over QoS signaling protocols.  The COPS-PR extension
   allows provision policy information on devises.

   +  COPS-PR allows high-level transactions for single devices,
      including deleting one configuration and replacing it with
      another.

   +  COPS-PRs non-overlapping instance namespace normally ensures that
      no other manager can corrupt a specific configuration.  All
      transactions for a given instance namespace are required to be
      executed in-order.

   +  Both manager and device states are completely synchronized with
      one another at all times.  If there is a failure in communication,
      the state is resynchronized when the network is operating properly
      again and the device's network configuration is valid.





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   +  The atomicity of transactions is well-defined.  If there is any
      failure in a transaction, that specific failure is reported to the
      manager, and the local configuration is supposed to be
      automatically rolled-back to the state of the last "good"
      transaction.

   +  Capability reporting is part of the framework PIB which must be
      supported by COPS-PR implementations.  This allows management
      applications to adapt to the capabilities present on a device.

   +  The focus of COPS-PR is configuration, and the protocol has been
      optimized for this purpose (by using for example TCP as a
      transport mechanism).

   o  Only a single manager is allowed to have control, at any point in
      time, for a given subject category on a device.  (The subject
      category maps to a COPS Client-Type.)  This single manager
      assumption simplifies the protocol as it makes it easier to
      maintain shared state.

   o  Similar to SNMP, COPS-PR requires applications to be useful since
      it is also designed as a programmatic interface between management
      applications and devices.

   -  As of the time of the meeting, there are no standardized PIB
      modules.

   -  Compared to SNMP, there is not yet enough experience to understand
      the strong and weak aspects of the protocol in operational
      environments.

   -  COPS-PR does not support easy retrieval and playback of
      configurations.  The reasons are similar as for SNMP.

   -  The COPS-PR view of the world is data-centric, similar to SNMP's
      view of the world.  A mapping from the data-centric view to a
      task-oriented view and vice versa, has similar complexities as
      with SNMP.

2.3 CIM / MOF / UML / PCIM

   The development of the Common Information Model (CIM) [CIM] started
   in the DMTF in the mid 1990s.  The development follows a top-down
   approach where core classes are defined first and later extended to
   model specific services.  The DMTF and the IETF jointly developed
   policy extensions of the CIM, known as PCIM [RFC3060].





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   +  The CIM technology generally follows principles of object-
      orientation with full support of methods on data objects, which is
      not available in SNMP or COPS-PR.

   +  The MOF format allows representation of instances in a common
      format.  No such common format exists for SNMP or COPS-PR.  It is
      of course possible to store instances in the form of BER encoded
      ASN.1 sequences, but this is generally not suitable for human
      readability.

   +  There is support for a query facility which allows the locating of
      CIM objects.  However, the query language itself is not yet
      specified as part of the CIM standards.  Implementations currently
      use proprietary query languages, such as the Windows Management
      Instrumentation Query Language (WQL).

   +  The information modeling work in CIM is done by using Unified
      Modeling Language (UML) as a graphical notation.  This attracts
      people with a computer science background who have learned to use
      UML as part of their education.

   o  The main practical use of CIM schemas today seems to be the
      definition of data structures used internally by management
      systems.

   -  The CIM schemas have rather complex interrelationships that must
      be understood before one can reasonably extend the set of existing
      schemas.

   -  Interoperability between CIM implementations seems to be
      problematic compared to the number of interoperable SNMP
      implementations available today.

   -  So far, CIM schemas have seen limited implementation and usage as
      an interface between management systems and network devices.

2.4 CLI / TELNET / SSH

   Most devices have a builtin command line interface (CLI) for
   configuration and troubleshooting purposes.  Network access to the
   CLI has traditionally been through the TELNET protocol, while the SSH
   protocol is gaining momentum to address security issues associated
   with TELNET.  In the following, only CLIs that actually parse and
   execute commands are considered.  (Menu-oriented interfaces are
   difficult for automation and thus not relevant here.)

   +  Command line interfaces are generally task-oriented, which make
      them easier to use for human operators.



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   +  A saved sequence of textual commands can easily be replayed.
      Simple substitutions can be made with arbitrary text processing
      tools.

   +  It is usually necessary to learn at least parts of the command
      line interface of new devices in order to create the initial
      configuration.  Once people have learned (parts of) the command
      line interface, it is natural for them to use the same interface
      and abstractions for automating configuration changes.

   +  A command line interface does not require any special purpose
      applications (telnet and ssh are readily available on most systems
      today).

   +  Most command line interfaces provide context sensitive help that
      reduces the learning curve.

   -  Some command line interfaces lack a common data model.  It is very
      well possible that the same command on different devices, even
      from the same vendor, behaves differently.

   -  The command line interface is primarily targeted to humans which
      can adapt to minor syntax and format changes easily.  Using
      command line interfaces as a programmatic interface is troublesome
      because of parsing complexities.

   -  Command line interfaces often lack proper version control for the
      syntax and the semantics.  It is therefore time consuming and
      error prone to maintain programs or scripts that interface with
      different versions of a command line interface.

   -  Since command line interfaces are proprietary, they can not be
      used efficiently to automate processes in an environment with a
      heterogenous set of devices.

   -  The access control facilities, if present at all, are often ad-hoc
      and sometimes insufficient.

2.5 HTTP / HTML

   Many devices have an embedded web server which can be used to
   configure the device and to obtain status information.  The commonly
   used protocol is HTTP, and information is rendered in HTML.  Some
   devices also expect that clients have facilities such as Java or Java
   Script.

   +  Embedded web servers for configuration are end-user friendly and
      solution oriented.



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   +  Embedded web servers are suitable for configuring consumer devices
      by inexperienced users.

   +  Web server configuration is widely deployed, especially in boxes
      targeted to the consumer market.

   +  There is no need for specialized applications to use embedded web
      servers since web browsers are commonly available today.

   -  Embedded web servers are management application hostile.  Parsing
      HTML pages to extract useful information is extremely painful.

   -  Replay of configuration is often problematic, either because the
      web pages rely on some active content or because different
      versions of the same device use different ways to interact with
      the user.

   -  The access control facilities, if present at all, are often ad-hoc
      and sometimes insufficient.

2.6 XML

   In the late 1990's, some vendors started to use the Extensible Markup
   Language (XML) [XML] for describing device configurations and for
   protocols that can be used to retrieve and manipulate XML formatted
   configurations.

   +  XML is a machine readable format which is easy to process and
      there are many good off the shelf tools available.

   +  XML allows the description of structured data of almost arbitrary
      complexity.

   +  The basic syntax rules behind XML are relatively easy to learn.

   +  XML provides a document-oriented view of configuration data
      (similar to many proprietary configuration file formats).

   +  XML has a robust schema language XSD [XSD] for which many good off
      the shelf tools exist.

   o  XML alone is just syntax.  XML schemas must be carefully designed
      to make XML truly useful as a data exchange format.








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   -  XML is rather verbose.  This either increases the bandwidth
      required to move management information around (which is an issue
      in e.g., wireless or asymmetric cable networks) or it requires
      that the systems involved have the processing power to do on the
      fly compression/decompression.

   -  There is a lack of commonly accepted standardized management
      specific XML schemas.

3. Operator Requirements

   During the breakout session, the operators were asked to identify
   needs that have not been sufficiently addressed.  The results
   produced during the breakout session were later discussed and
   resulted in the following list of operator requirements.

   1.  Ease of use is a key requirement for any network management
       technology from the operators point of view.

   2.  It is necessary to make a clear distinction between configuration
       data, data that describes operational state and statistics.  Some
       devices make it very hard to determine which parameters were
       administratively configured and which were obtained via other
       mechanisms such as routing protocols.

   3.  It is required to be able to fetch separately configuration data,
       operational state data, and statistics from devices, and to be
       able to compare these between devices.

   4.  It is necessary to enable operators to concentrate on the
       configuration of the network as a whole rather than individual
       devices.

   5.  Support for configuration transactions across a number of devices
       would significantly simplify network configuration management.

   6.  Given configuration A and configuration B, it should be possible
       to generate the operations necessary to get from A to B with
       minimal state changes and effects on network and systems.  It is
       important to minimize the impact caused by configuration changes.

   7.  A mechanism to dump and restore configurations is a primitive
       operation needed by operators.  Standards for pulling and pushing
       configurations from/to devices are desirable.







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   8.  It must be easy to do consistency checks of configurations over
       time and between the ends of a link in order to determine the
       changes between two configurations and whether those
       configurations are consistent.

   9.  Network wide configurations are typically stored in central
       master databases and transformed into formats that can be pushed
       to devices, either by generating sequences of CLI commands or
       complete configuration files that are pushed to devices.  There
       is no common database schema for network configuration, although
       the models used by various operators are probably very similar.
       It is desirable to extract, document, and standardize the common
       parts of these network wide configuration database schemas.

   10. It is highly desirable that text processing tools such as diff,
       and version management tools such as RCS or CVS, can be used to
       process configurations, which implies that devices should not
       arbitrarily reorder data such as access control lists.

   11. The granularity of access control needed on management interfaces
       needs to match operational needs.  Typical requirements are a
       role-based access control model and the principle of least
       privilege, where a user can be given only the minimum access
       necessary to perform a required task.

   12. It must be possible to do consistency checks of access control
       lists across devices.

   13. It is important to distinguish between the distribution of
       configurations and the activation of a certain configuration.
       Devices should be able to hold multiple configurations.

   14. SNMP access control is data-oriented, while CLI access control is
       usually command (task) oriented.  Depending on the management
       function, sometimes data-oriented or task-oriented access control
       makes more sense.  As such, it is a requirement to support both
       data-oriented and task-oriented access control.

   So far, there is no published document that clearly defines the
   requirements of the operators.











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4. SNMP Framework Discussions

   During the discussions, many properties of the SNMP framework were
   identified.

   1.  It is usually not possible to retrieve complete device
       configurations via SNMP so that they can be compared with
       previous configurations or checked for consistency across
       devices.  There is usually only incomplete coverage of device
       features via the SNMP interface, and there is a lack of
       differentiation between configuration data and operational state
       data for many features.

   2.  The quality of SNMP instrumentations is sometimes disappointing.
       SNMP access sometimes crashes systems or returns wrong data.

   3.  MIB modules and their implementations are not available in a
       timely manner (sometimes MIB modules lag years behind) which
       forces users to use the CLI.

   4.  Operators view current SNMP programming/scripting interfaces as
       being too low-level and thus too time consuming and inconvenient
       for practical use.

   5.  Lexicographic ordering is sometimes artificial with regard to
       internal data structures and causes either significant runtime
       overhead, or increases implementation costs or implementation
       delay or both.

   6.  Poor performance for bulk data transfers.  The typical examples
       are routing tables.

   7.  Poor performance on query operations that were not anticipated
       during the MIB design.  A typical example is the following query:
       Which outgoing interface is being used for a specific destination
       address?

   8.  The SNMP credentials and key management are considered complex,
       especially since they do not integrate well with other existing
       credential and key management systems.

   9.  The SMI language is hard to deal with and not very practical.

   10. MIB modules are often over-engineered in the sense that they
       contain lots of variables that operators do not look at.






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   11. SNMP traps are used to track state changes but often syslog
       messages are considered more useful since they usually contain
       more information to describe the problem.  SNMP traps usually
       require subsequent get operations to figure out what the trap
       really means.

   12. Device manufacturers find SNMP instrumentations inherently
       difficult to implement, especially with complex table indexing
       schemes and table interrelationships.

   13. MIB modules often lack a description of how the various objects
       can be used to achieve certain management functions.  (MIB
       modules can often be characterized as a list of ingredients
       without a recipe.)

   14. The lack of structured types and various RPC interactions
       (methods) make MIB modules much more complex to design and
       implement.

   15. The lack of query and aggregation capabilities (reduction of
       data) causes efficiency and scalability problems.

   16. The SNMP protocol was simplified in terms of the number of
       protocol operations and resource requirements on managed devices.
       It was not simplified in terms of usability by network operators
       or instrumentation implementors.

   17. There is a semantic mismatch between the low-level data-oriented
       abstraction level of MIB modules and the task-oriented
       abstraction level desired by network operators.  Bridging the gap
       with tools is in principle possible, but in general it is
       expensive as it requires some serious development and programming
       efforts.

   18. SNMP seems to work reasonably well for small devices which have a
       limited number of managed objects and where end-user management
       applications are shipped by the vendor.  For more complex
       devices, SNMP becomes too expensive and too hard to use.

   19. There is a disincentive for vendors to implement SNMP equivalent
       MIB modules for all their CLI commands because they do not see a
       valued proposition.  This undermines the value of third party
       standard SNMP solutions.

   20. Rapid feature development is in general not compatible with the
       standardization of the configuration interface.





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5. Consolidated Observations

   1.  Programmatic interfaces have to provide full coverage otherwise
       they will not be used by network operators since they have to
       revert to CLIs anyway.

   2.  Operators perceive that equipment vendors do not implement MIB
       modules in a timely manner.  Neither read-only nor read-write MIB
       modules are available on time today.

   3.  The attendees perceive that right now it is too hard to implement
       useful MIB modules within network equipment.

   4.  Because of the previous items, SNMP is not widely used today for
       network device configuration, although there are notable
       exceptions.

   5.  It is necessary to clearly distinguish between configuration data
       and operational data.

   6.  It would be nice to have a single data definition language for
       all programmatic interfaces (in case there happen to be multiple
       programmatic interfaces).

   7.  In general, there is a lack of input from the enterprise network
       space.  Those enterprises who provided input tend to operate
       their networks like network operators.

   8.  It is required to be able to dump and reload a device
       configuration in a textual format in a standard manner across
       multiple vendors and device types.

   9.  It is desirable to have a mechanism to distribute configurations
       to devices under transactional constraints.

   10. Eliminating SNMP altogether is not an option.

   11. Robust access control is needed.  In addition, it is desirable to
       be able to enable/disable individual MIB modules actually
       implemented on a device.

   12. Textual configuration files should be able to contain
       international characters.  Human-readable strings should utilize
       the least-bad internationalized character set and encoding, which
       this year almost certainly means UTF-8.  Protocol elements should
       be in case insensitive ASCII.





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   13. The deployed tools for event/alarm correlation, root cause
       analysis and logging are not sufficient.

   14. There is a need to support a human interface and a programmatic
       interface.

   15. The internal method routines for both interfaces should be the
       same to ensure that data exchanged between these two interfaces
       is always consistent.

   16. The implementation costs have to be low on devices.

   17. The implementation costs have to be low on managers.

   18. The specification costs for data models have to be low.

   19. Standardization costs for data models have to be low.

   20. There should be a single data modeling language with a human
       friendly syntax.

   21. The data modeling language must support compound data types.

   22. There is a need for data aggregation capabilities on the devices.

   23. There should be a common data interchange format for instance
       data that allows easy post-processing and analysis.

   24. There is a need for a common data exchange format with single and
       multi-system transactions (which implies rollback across devices
       in error situations).

   25. There is a need to reduce the semantic mismatch between current
       data models and the primitives used by operators.

   26. It should be possible to perform operations on selected subsets
       of management data.

   27. It is necessary to discover the capabilities of devices.

   28. There is a need for a secure transport, authentication, identity,
       and access control which integrates well with existing key and
       credential management infrastructure.

   29. It must be possible to define task oriented views and access
       control rules.





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RFC 3535            IAB Network Management Workshop             May 2003


   30. The complete configuration of a device should be doable with a
       single protocol.

   31. A configuration protocol must be efficient and reliable and it
       must scale in the number of transactions and devices.

   32. Devices must be able to support minimally interruptive
       configuration deltas.

   33. A solution must support function call semantics (methods) to
       implement functions, such as a longest prefix match on a routing
       table.

6. Recommendations

   1.  The workshop recommends that the IETF stop forcing working groups
       to provide writable MIB modules.  It should be the decision of
       the working group whether they want to provide writable objects
       or not.

   2.  The workshop recommends that a group be formed to investigate why
       current MIB modules do not contain all the objects needed by
       operators to monitor their networks.

   3.  The workshop recommends that a group be formed to investigate why
       the current SNMP protocol does not satisfy all the monitoring
       requirements of operators.

   4.  The workshop recommends, with strong consensus from both protocol
       developers and operators, that the IETF focus resources on the
       standardization of configuration management mechanisms.

   5.  The workshop recommends, with strong consensus from the operators
       and rough consensus from the protocol developers, that the
       IETF/IRTF should spend resources on the development and
       standardization of XML-based device configuration and management
       technologies (such as common XML configuration schemas, exchange
       protocols and so on).

   6.  The workshop recommends, with strong consensus from the operators
       and rough consensus from the protocol developers, that the
       IETF/IRTF should not spend resources on developing HTML-based or
       HTTP-based methods for configuration management.








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RFC 3535            IAB Network Management Workshop             May 2003


   7.  The workshop recommends, with rough consensus from the operators
       and strong consensus from the protocol developers, that the IETF
       should continue to spend resources on the evolution of the
       SMI/SPPI data definition languages as being done in the SMIng
       working group.

   8.  The workshop recommends, with split consensus from the operators
       and rough consensus from the protocol developers, that the IETF
       should spend resources on fixing the MIB development and
       standardization process.

   The workshop also discussed the following items and achieved rough
   consensus, but did not make a recommendation.

   1.  The workshop had split consensus from the operators and rough
       consensus from the protocol developers, that the IETF should not
       focus resources on CIM extensions.

   2.  The workshop had rough consensus from the protocol developers
       that the IETF should not spend resources on COPS-PR development.
       So far, the operators have only very limited experience with
       COPS-PR.  In general, however, they felt that further development
       of COPS-PR might be a waste of resources as they assume that
       COPS-PR does not really address their requirements.

   3.  The workshop had rough consensus from the protocol developers
       that the IETF should not spend resources on SPPI PIB definitions.
       The operators had rough consensus that they do not care about
       SPPI PIBs.

7. Security Considerations

   This document is a report of an IAB Network Management workshop.  As
   such, it does not have any direct security implications for the
   Internet.

8. Acknowledgments

   The editor would like to thank Dave Durham, Simon Leinen and John
   Schnizlein for taking detailed minutes during the workshop.











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Normative References

   [RFC3410]  Case, J., Mundy, R., Partain, D. and B. Stewart,
              "Introduction and Applicability Statements for Internet-
              Standard Management Framework", RFC 3410, December 2002.

   [CIM]      Distributed Management Task Force, "Common Information
              Model (CIM) Specification Version 2.2", DSP 0004, June
              1999.

   [RFC3060]  Moore, B., Ellesson, E., Strassner, J. and A. Westerinen,
              "Policy Core Information Model -- Version 1
              Specification", RFC 3060, February 2001.

   [RFC2748]  Durham, D., Boyle, J., Cohen, R., Herzog, S., Rajan, R.
              and A. Sastry, "The COPS (Common Open Policy Service)
              Protocol", RFC 2748, January 2000.

   [RFC3084]  Chan, K., Seligson, J., Durham, D., Gai, S., McCloghrie,
              K., Herzog, S., Reichmeyer, F., Yavatkar, R. and A. Smith,
              "COPS Usage for Policy Provisioning (COPS-PR)", RFC 3084,
              March 2001.

   [XML]      Bray, T., Paoli, J. and C. Sperberg-McQueen, "Extensible
              Markup Language (XML) 1.0", W3C Recommendation, February
              1998.

Informative References

   [RFC2863]  McCloghrie, K. and F. Kastenholz, "The Interfaces Group
              MIB", RFC 2863, June 2000.

   [XSD]      David, D., "XML Schema Part 0: Primer", W3C
              Recommendation, May 2001.

















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RFC 3535            IAB Network Management Workshop             May 2003


Appendix - Participants

   Ran Atkinson          Extreme Networks
   Rob Austein           InterNetShare
   Andy Bierman          Cisco Systems
   Steve Bellovin        AT&T
   Randy Bush            AT&T
   Leslie Daigle         VeriSign
   David Durham          Intel
   Vijay Gill
   Wes Hardaker          Network Associates Laboratories
   Ed Kern
   Simon Leinen          Switch
   Ken Lindahl           University of California Berkeley
   David Partain         Ericsson
   Andrew Partan         UUnet/Verio/MFN
   Vern Paxson           ICIR
   Aiko Pras             Univeristy of Twente
   Randy Presuhn         BMC Software
   Juergen Schoenwaelder University of Osnabrueck
   John Schnizlein       Cisco Systems
   Mike St. Johns
   Ruediger Volk         Deutsche Telekom
   Steve Waldbusser
   Margaret Wassermann   Windriver
   Glen Waters           Nortel Networks
   Bert Wijnen           Lucent

Author's Address

   Comments should be submitted to the  mailing
   list.

   Juergen Schoenwaelder
   International University Bremen
   P.O. Box 750 561
   28725 Bremen
   Germany

   Phone: +49 421 200 3587
   EMail: j.schoenwaelder@iu-bremen.de










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RFC 3535            IAB Network Management Workshop             May 2003


Full Copyright Statement

   Copyright (C) The Internet Society (2003).  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 assignees.

   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.

Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.



















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