Network Working Group                                       M. Behringer
Internet-Draft                                               M. Pritikin
Intended status: Informational                              S. Bjarnason
Expires: April 19, 2014                                         A. Clemm
                                                           Cisco Systems
                                                        October 16, 2013

                  A Framework for Autonomic Networking


   Autonomic systems were first described in 2001.  The fundamental goal
   is self-management, including self-configuration, self-optimization,
   self-healing and self-protection.

   This document applies the concepts of autonomic systems to a network,
   and describes a framework for Autonomic Networking.  The goal is a
   network where nodes have minimal dependencies on human administrators
   or centralized management systems.

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

   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 April 19, 2014.

Copyright Notice

   Copyright (c) 2013 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
   ( in effect on the date of
   publication of this document.  Please review these documents

Behringer, et al.        Expires April 19, 2014                 [Page 1]

Internet-Draft            Autonomic Networking              October 2013

   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction to Autonomic Networking  . . . . . . . . . . . .   2
   2.  Definitions . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Fundamental Concepts  . . . . . . . . . . . . . . . . . . . .   3
     3.1.  Domain Identity . . . . . . . . . . . . . . . . . . . . .   3
     3.2.  Discovery . . . . . . . . . . . . . . . . . . . . . . . .   4
     3.3.  Intent  . . . . . . . . . . . . . . . . . . . . . . . . .   4
     3.4.  Abstraction . . . . . . . . . . . . . . . . . . . . . . .   4
     3.5.  Autonomic Reporting . . . . . . . . . . . . . . . . . . .   5
     3.6.  Decentralisation and Distribution . . . . . . . . . . . .   5
     3.7.  Modularity  . . . . . . . . . . . . . . . . . . . . . . .   6
     3.8.  Independence of Function and Layer  . . . . . . . . . . .   6
     3.9.  Full Life Cycle Support . . . . . . . . . . . . . . . . .   6
   4.  An Autonomic Framework  . . . . . . . . . . . . . . . . . . .   7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   8
   7.  Informative References  . . . . . . . . . . . . . . . . . . .   9
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   9

1.  Introduction to Autonomic Networking

   Autonomic systems were first described in a manifesto by IBM in 2001
   [Kephart].  The fundamental concept involves eliminating external
   systems from a system's control loops and closing of control loops
   within the autonomic system itself, with the goal of providing the
   autonomic system with self-management capabilities, including self-
   configuration, self-optimization, self-healing and self-protection.

   IP networking was initially designed with similar properties in mind.
   An IP network should be distributed and redundant to withstand
   outages in any part of the network.  A routing protocol such as OSPF
   or ISIS exhibits properties of self-management, and can thus be
   considered autonomic in the definition of this framework.

   However, as IP networking evolved, the ever increasing intelligence
   of network element was often not put into protocols to follow this
   paradigm, but into configuration.  This configuration made network
   elements highly dependent on some process that manages them, either a
   human, or a network management system.

Behringer, et al.        Expires April 19, 2014                 [Page 2]

Internet-Draft            Autonomic Networking              October 2013

   Autonomic Networking aims at putting the intelligence of today's
   operations back into algorithms at the node level, to minimize
   dependency on human administrators and central management systems.
   Some information an autonomic node requires however cannot be
   discovered; where input from some central intelligence is required,
   it is provided in a highly abstract, network wide form.

   This document provides a framework for achieving this goal.

2.  Definitions

   Autonomic: Self-managing (self-configuring, self-protecting, self-
   healing and self-optimizing); however, allowing high-level guidance
   by a central entity, through intent.

   Intent: An abstract, high level policy used to operate the network
   autonomically.  Its scope is an autonomic domain, such as an
   enterprise network.  It does not contain configuration or information
   for a specific node.  It may contain information pertaining to nodes
   with a specific role.

   Autonomic Domain: A collection of autonomic nodes that instantiate
   the same intent.

   Autonomic Function: A function which requires no configuration, and
   can derive all required information either through self-knowledge,
   discovery or through intent.

   Autonomic Node: A node which employs autonomic functions.  It may
   operate on any layer of the networking stack.  Examples are routers,
   switches, personal computers, call managers, etc.

   Fully Autonomic Node: A node which employs exclusively autonomic
   functions.  It requires no configuration.

   Autonomic Network: A network containing autonomic nodes.

   Fully Autonomic Network: A network consisting of exclusively fully
   autonomic nodes.

3.  Fundamental Concepts

3.1.  Domain Identity

   Any member of the domain can assert its membership using a domain
   identity, for example a certificate issued by a domain certification
   authority.  This domain identity is used for nodes to learn about
   their neighbouring nodes, to determine the boundaries of the domain,

Behringer, et al.        Expires April 19, 2014                 [Page 3]

Internet-Draft            Autonomic Networking              October 2013

   and to cryptographically secure interactions within the domain.
   Nodes from different domains can also mutually verify their identity
   and secure interactions as long as they have a common trust anchor.

   A strong, cryptographically verifiable domain identity is a
   fundamental cornerstone in autonomic networking.  It can be leveraged
   to secure all communications, and allows thus automatic security
   without traditional configuration, for example pre-shared keys.

   Autonomic nodes must be able to adapt their behaviour depending on
   the domain of the node they are interacting with.

3.2.  Discovery

   In traditional networks, significant amounts of the information that
   a node needs to operate are provided through northbound interfaces,
   for example configuration.  An autonomic node has a minimal
   northbound interface, limited to receiving intent and providing
   feedback loops.

   Discovery is the default way for a node to receive the information it
   needs to operate.

   There are certain pieces of information that a node cannot discover,
   because they derive from non-technical business objectives.  For
   example a routing policy cannot be discovered through intelligence in
   the network.  This type of information is an exception to the rule of
   "default discover", and is propagated in intent.

3.3.  Intent

   An autonomic network has to allow for input from the outside to guide
   the network's behaviour.  The administrator's desired behaviour of
   the network is expressed as "intent".  It contains certain
   information which is derived from business level objectives.  Intent
   should only include information which the network cannot infer or

   Intent has a network wide scope and must be communicated to all nodes
   of the network, independent of their function.  A node may
   instantiate only the portions of intent that are relevant to its
   function.  Intent must not be used to address specific nodes or
   locations in the network.

3.4.  Abstraction

   An administrator or autonomic management system interacts with an
   autonomic network on a high level of abstraction.  Intent is defined

Behringer, et al.        Expires April 19, 2014                 [Page 4]

Internet-Draft            Autonomic Networking              October 2013

   at a level of abstraction that is much higher than that of typical
   configuration parameters, for example, "optimize my network for
   energy efficiency".  Intent must not be used to convey low-level
   commands or concepts, since those are on a different abstraction
   level.  The administrator should not even be exposed to the version
   of the IP protocol running in the network.

   Also on the reporting and feedback side an autonomic network
   abstracts information and provides high-level messages such as "the
   link between node X and Y is down".

3.5.  Autonomic Reporting

   An autonomic network, while minimizing the need for user
   intervention, still needs to provide users with visibility like in
   traditional networks.  However, in an autonomic network reporting
   should happen on a network wide basis.  Information about the network
   should be collected and aggregated by the network itself, presented
   in consolidated fashion to the administrator.

   The layers of abstraction that are provided via intent need to be
   supported for reporting functions as well, in order to give users an
   indication about the effectiveness of their intent.  For example, in
   order to assess how effective the network performs with regards to
   the intent "optimize my network for energy efficiency", the network
   should provide aggregate information about the number of ports that
   were able to be shut down while validating current service levels are
   on aggregate still met.

   Autonomic network events should concern the autonomic network as a
   whole, not individual systems in isolation.  For example, the same
   failure symptom should not be reported from every system that
   observes it, but only once for the autonomic network as a whole.
   Ultimately, the autonomic network should support exception based
   management, in which only events that truly require user attention
   are actually notified.  This requires capabilities that allow systems
   within the network to compare information and apply special
   algorithms to determine what should be reported.

3.6.  Decentralisation and Distribution

   The goal of Autonomic Networking is to minimise dependencies on
   central elements; therefore, de-centralisation and distribution are
   fundamental to the concept.  If a problem can be solved in a
   distributed manner, it should not be centralised.

   In certain cases it is today operationally preferable to keep a
   central repository of information, for example a user database on a

Behringer, et al.        Expires April 19, 2014                 [Page 5]

Internet-Draft            Autonomic Networking              October 2013

   AAA server.  An autonomic network must also be able to use such
   central systems, in order to be deployable.  However, it is possible
   to distribute such databases as well, and such efforts should be at
   least considered.

3.7.  Modularity

   It is unrealistic to expect a fully autonomic network in complex
   environments for many years to come.  While simple networks may
   become autonomic in one single step, a phased approach is required
   for most of today's networks.

   Autonomic functions can be implemented in a modular way.  For
   example, the internal routing algorithm in many networks today is
   already mostly autonomic.  Other modules can be made autonomic step
   by step.

3.8.  Independence of Function and Layer

   Today's autonomic functions may reside on any layer in the networking
   stack.  For example, layer 2 switching today is already relatively
   autonomic in many environments; routing functions can be autonomic.
   "Autonomic" in the context of this framework is a property of a node.
   This node can be a switch, router, server, or call manager.
   Autonomic functionality is independent of the function of a node.
   Even application layer functionality such as unified communications
   can be autonomic.

   An Autonomic Network requires an overall control plane for autonomic
   nodes to communicate.  As in general IP networking, IP is the layer
   that binds all those elements together; autonomic functions in the
   context of this framework should therefore operate at the IP layer.
   This concerns neighbour discovery protocols and other autonomic
   control plane functions.

3.9.  Full Life Cycle Support

   An autonomic node does not depend on external input to operate; it
   needs to understand its current situation and surrounding, and
   operate according to its current state.  Therefore, an autonomic node
   must understand its full life cycle, from first manufacturing testing
   through deployment, testing, troubleshooting, up to decommissioning.

   The state of the life-cycle of an autonomic node is reflected in a
   state model.  The behaviour of an autonomic node may be different for
   different deployment states.

Behringer, et al.        Expires April 19, 2014                 [Page 6]

Internet-Draft            Autonomic Networking              October 2013

4.  An Autonomic Framework

   An Autonomic Network consists of Autonomic Nodes.  Those nodes
   communicate with each other through an Autonomic Control Plane which
   provides a robust and secure communications overlay.  The Autonomic
   Control Plane is self-organizing and autonomic itself.

   An Autonomic Node contains various elements, such as autonomic
   service agents.  Figure 1 shows a reference model of an autonomic
   node.  The elements and their interaction are:

   o  Autonomic Service Agents, which implement the autonomic behaviour
      of a specific service or function.

   o  Self-knowledge: An autonomic node knows its own properties and

   o  Network Knowledge (Discovery): An autonomic service agent may
      require various discovery functions in the network, such as
      service discovery.

   o  Intent: Network wide high level policy.  Autonomic Service Agents
      use an intent interpretation engine to locally instantiate the
      global intent.  This may involve coordination with other Autonomic

   o  Feedback Loops: Control elements outside the node may interact
      with autonomic nodes through feedback loops.

   o  An Autonomic User Agent, providing a front-end to external users
      (administrators and management applications) through which they
      can communicate intent, receive reports, and monitor the Autonomic

   o  Autonomic Control Plane: Allows the node to communicate with other
      autonomic nodes.  Autonomic functions such as intent distribution,
      feedback loops, discovery mechanisms, etc, use the autonomic
      control plane.

Behringer, et al.        Expires April 19, 2014                 [Page 7]

Internet-Draft            Autonomic Networking              October 2013

   |               +----------+ +--------------+                |
   |               |          | | Feedback     |                |
   |               | Intent   | |    Loops     |                |
   |               +----------+ +--------------+                |
   |                         ^     ^                            |
   |                    Autonomic User Agent                    |
   |                         V     V                            |
   | +-----------+        +------------+        +------------+  |
   | | Self-     |        | Autonomic  |        | Network    |  |
   | | knowledge |<------>| Service    |<------>| Knowledge  |  |
   | |           |        | Agents     |        | (Discovery)|  |
   | +-----------+        +------------+        +------------+  |
   |                            ^                     ^         |
   |                            |                     |         |
   |                            V                     V         |
   |                 Autonomic Control Plane                    |
   |           Standard Operating System Functions              |

                                 Figure 1

5.  Security Considerations

   This document specifies a framework.  Security is an integral part of
   this framework.

6.  Acknowledgements

   The work on Autonomic Networking is the result of a large team
   project at Cisco Systems.  In alphabetical order: Ignas Bagdonas,
   Parag Bhide, Balaji BL, Toerless Eckert, Yves Hertoghs, Bruno

   The ETSI working group AFI ( defines a
   similar framework for autonomic networking in the "General Autonomic
   Network Architecture" [GANA].  Many concepts explained in this
   document can be mapped to the GANA framework.  The mapping is outside
   the scope of this document.  Special thanks to Ranganai Chaparadza
   for his comments and help on this document.

Behringer, et al.        Expires April 19, 2014                 [Page 8]

Internet-Draft            Autonomic Networking              October 2013

7.  Informative References

   [GANA]     ETSI GS AFI 002, ., "Autonomic network engineering for the
              self-managing Future Internet (AFI): GANA Architectural
              Reference Model for Autonomic Networking, Cognitive
              Networking and Self-Management. ", April 2013, <http://

   [Kephart]  Kephart, J. and D. Chess, "The Vision of Autonomic
              Computing", IEEE Computer vol. 36, no. 1, pp. 41-50,
              January 2003.

Authors' Addresses

   Michael H. Behringer
   Cisco Systems


   Max Pritikin
   Cisco Systems


   Steinthor Bjarnason
   Cisco Systems


   Alex Clemm
   Cisco Systems


Behringer, et al.        Expires April 19, 2014                 [Page 9]