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INFORMATIONAL
Internet Research Task Force (IRTF)                             S. JiangRequest for Comments: 7576                  Huawei Technologies Co., LtdCategory: Informational                                     B. CarpenterISSN: 2070-1721                                        Univ. of Auckland                                                            M. Behringer                                                           Cisco Systems                                                               June 2015General Gap Analysis for Autonomic NetworkingAbstract   This document provides a problem statement and general gap analysis   for an IP-based Autonomic Network that is mainly based on distributed   network devices.  The document provides background by reviewing the   current status of autonomic aspects of IP networks and the extent to   which current network management depends on centralization and human   administrators.  Finally, the document outlines the general features   that are missing from current network abilities and are needed in the   ideal Autonomic Network concept.   This document is a product of the IRTF's Network Management Research   Group.Status of This Memo   This document is not an Internet Standards Track specification; it is   published for informational purposes.   This document is a product of the Internet Research Task Force   (IRTF).  The IRTF publishes the results of Internet-related research   and development activities.  These results might not be suitable for   deployment.  This RFC represents the consensus of the Network   Management Research Group of the Internet Research Task Force (IRTF).   Documents approved for publication by the IRSG are not a candidate   for any level of Internet Standard; seeSection 2 of RFC 5741.   Information about the current status of this document, any errata,   and how to provide feedback on it may be obtained athttp://www.rfc-editor.org/info/rfc7576.Jiang, et al.                 Informational                     [Page 1]

RFC 7576            Autonomic Networking Gap Analysis          June 2015Copyright Notice   Copyright (c) 2015 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject toBCP 78 and the IETF Trust's Legal   Provisions Relating to IETF Documents   (http://trustee.ietf.org/license-info) in effect on the date of   publication of this document.  Please review these documents   carefully, as they describe your rights and restrictions with respect   to this document.Table of Contents1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .32.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .33.  Automatic and Autonomic Aspects of Current IP Networks  . . .33.1.  IP Address Management and DNS . . . . . . . . . . . . . .33.2.  Routing . . . . . . . . . . . . . . . . . . . . . . . . .53.3.  Configuration of Default Router in a Host . . . . . . . .53.4.  Hostname Lookup . . . . . . . . . . . . . . . . . . . . .53.5.  User Authentication and Accounting  . . . . . . . . . . .63.6.  Security  . . . . . . . . . . . . . . . . . . . . . . . .63.7.  State Synchronization . . . . . . . . . . . . . . . . . .74.  Current Non-autonomic Behaviors . . . . . . . . . . . . . . .74.1.  Building a New Network  . . . . . . . . . . . . . . . . .74.2.  Network Maintenance and Management  . . . . . . . . . . .84.3.  Security Setup  . . . . . . . . . . . . . . . . . . . . .94.4.  Troubleshooting and Recovery  . . . . . . . . . . . . . .95.  Features Needed by Autonomic Networks . . . . . . . . . . . .105.1.  More Coordination among Devices or Network Partitions . .115.2.  Reusable Common Components  . . . . . . . . . . . . . . .115.3.  Secure Control Plane  . . . . . . . . . . . . . . . . . .125.4.  Less Configuration  . . . . . . . . . . . . . . . . . . .125.5.  Forecasting and Dry Runs  . . . . . . . . . . . . . . . .135.6.  Benefit from Knowledge  . . . . . . . . . . . . . . . . .136.  Security Considerations . . . . . . . . . . . . . . . . . . .147.  Informative References  . . . . . . . . . . . . . . . . . . .14   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .17   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .17Jiang, et al.                 Informational                     [Page 2]

RFC 7576            Autonomic Networking Gap Analysis          June 20151.  Introduction   The general goals and relevant definitions for Autonomic Networking   are discussed in [RFC7575].  In summary, the fundamental goal of an   Autonomic Network is self-management, including self-configuration,   self-optimization, self-healing, and self-protection.  Whereas   interior gateway routing protocols such as OSPF and IS-IS largely   exhibit these properties, most other aspects of networking require   top-down configuration, often involving human administrators and a   considerable degree of centralization.  In essence, Autonomic   Networking is putting all network configurations onto the same   footing as routing, limiting manual or database-driven configuration   to an essential minimum.  It should be noted that this is highly   unlikely to eliminate the need for human administrators, because many   of their essential tasks will remain.  The idea is to eliminate   tedious and error-prone tasks, for example, manual calculations,   cross-checking between two different configuration files, or tedious   data entry.  Higher-level operational tasks, and complex   troubleshooting, will remain to be done by humans.   This document represents the consensus of the IRTF's Network   Management Research Group (NMRG).  It first provides background by   identifying examples of partial autonomic behavior in the Internet   and by describing important areas of non-autonomic behavior.  Based   on these observations, it then describes missing general mechanisms   that would allow autonomic behaviors to be added throughout the   Internet.2.  Terminology   The terminology defined in [RFC7575] is used in this document.3.  Automatic and Autonomic Aspects of Current IP Networks   This section discusses the history and current status of automatic or   autonomic operations in various aspects of network configuration, in   order to establish a baseline for the gap analysis.  In particular,   routing protocols already contain elements of autonomic processes,   such as information exchange and state synchronization.3.1.  IP Address Management and DNS   For many years, there was no alternative to completely manual and   static management of IP addresses and their prefixes.  Once a site   had received an IPv4 address assignment (usually a Class C /24 or   Class B /16, and rarely a Class A /8), it was a matter of paper-and-   pencil design of the subnet plan (if relevant) and the addressing   plan itself.  Subnet prefixes were manually configured into routers,Jiang, et al.                 Informational                     [Page 3]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   and /32 addresses were assigned administratively to individual host   computers and configured manually by system administrators.  Records   were typically kept in a plain text file or a simple spreadsheet.   Clearly, this method was clumsy and error-prone as soon as a site had   more than a few tens of hosts, but it had to be used until DHCP   [RFC2131] became a viable solution during the second half of the   1990s.  DHCP made it possible to avoid manual configuration of   individual hosts (except, in many deployments, for a small number of   servers configured with static addresses).  Even so, prefixes had to   be manually assigned to subnets and their routers, and DHCP servers   had to be configured accordingly.   In terms of management, there is a linkage between IP address   management and DNS management, because DNS mappings typically need to   be appropriately synchronized with IP address assignments.  At   roughly the same time as DHCP came into widespread use, it became   very laborious to manually maintain DNS source files in step with IP   address assignments.  Because of reverse DNS lookup, it also became   necessary to synthesize DNS names even for hosts that only played the   role of clients.  Therefore, it became necessary to synchronize DHCP   server tables with forward and reverse DNS.  For this reason, IP   address management tools emerged, as discussed for the case of   renumbering in [RFC7010].  These are, however, centralized solutions   that do not exhibit autonomic properties as defined in [RFC7575].   A related issue is prefix delegation, especially in IPv6 when more   than one prefix may be delegated to the same physical subnet.  DHCPv6   Prefix Delegation [RFC3633] is a useful solution, but it requires   specific configuration so cannot be considered autonomic.  How this   topic is to be handled in home networks is still in discussion   [Pfister].  Still further away is autonomic assignment and delegation   of routable IPv4 subnet prefixes.   An IPv6 network needs several aspects of host address assignments to   be configured.  The network might use stateless address   autoconfiguration [RFC4862] or DHCPv6 [RFC3315] in stateless or   stateful modes, and there are various alternative forms of Interface   Identifier [RFC7136].   Another feature is the possibility of Dynamic DNS Update [RFC2136].   With appropriate security, this is an automatic approach, where no   human intervention is required to create the DNS records for a host   after it acquires a new address.  However, there are coexistence   issues with a traditional DNS setup, as described in [RFC7010].Jiang, et al.                 Informational                     [Page 4]

RFC 7576            Autonomic Networking Gap Analysis          June 20153.2.  Routing   Since a very early stage, it has been a goal that Internet routing   should be self-healing when there is a failure of some kind in the   routing system (i.e., a link or a router goes wrong).  Also, the   problem of finding optimal routes through a network was identified   many years ago as a problem in mathematical graph theory, for which   well known algorithms were discovered (the Dijkstra and Bellman-Ford   algorithms).  Thus, routing protocols became largely autonomic from   the start, as it was clear that manual configuration of routing   tables for a large network was impractical.   IGP routers do need some initial configuration data to start up the   autonomic routing protocol.  Also, BGP-4 routers need detailed static   configuration of routing policy data.3.3.  Configuration of Default Router in a Host   Originally, the configuration of a default router in a host was a   manual operation.  Since the deployment of DHCP, this has been   automatic as far as most IPv4 hosts are concerned, but the DHCP   server must be appropriately configured.  In simple environments such   as a home network, the DHCP server resides in the same box as the   default router, so this configuration is also automatic.  In more   complex environments, where an independent DHCP server or a local   DHCP relay is used, DHCP configuration is more complex and not   automatic.   In IPv6 networks, the default router is provided by Router   Advertisement messages [RFC4861] from the router itself, and all IPv6   hosts make use of it.  The router may also provide more complex Route   Information Options.  The process is essentially autonomic as far as   all IPv6 hosts are concerned, and DHCPv6 is not involved.  However,   there are still open issues when more than one prefix is in use on a   subnet, and more than one first-hop router may be available as a   result (see, for example, [RFC6418]).3.4.  Hostname Lookup   Originally, hostnames were looked up in a static table, often   referred to as "hosts.txt" from its traditional file name.  When the   DNS was deployed during the 1980s, all hosts needed DNS resolver code   and needed to be configured with the IP addresses (not the names) of   suitable DNS servers.  Like the default router, these were originally   manually configured.  Today, they are provided automatically via DHCP   or DHCPv6 [RFC3315].  For IPv6 end systems, there is also a way for   them to be provided automatically via a Router Advertisement option.   However, the DHCP or DHCPv6 server, or the IPv6 router, needs to beJiang, et al.                 Informational                     [Page 5]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   configured with the appropriate DNS server addresses.  Additionally,   some networks deploy Multicast DNS [RFC6762] locally to provide   additional automation of the name space.3.5.  User Authentication and Accounting   Originally, user authentication and accounting was mainly based on   physical connectivity and the degree of trust that follows from   direct connectivity.  Network operators charged based on the setup of   dedicated physical links with users.  Automated user authentication   was introduced by the Point-to-Point Protocol [RFC1661], [RFC1994]   and RADIUS protocol [RFC2865] [RFC2866] in the early 1990s.  As long   as a user completes online authentication through the RADIUS   protocol, the accounting for that user starts on the corresponding   Authentication, Authorization, and Accounting (AAA) server   automatically.  This mechanism enables business models with charging   based on the amount of traffic or time.  However, user authentication   information continues to be manually managed by network   administrators.  It also becomes complex in the case of mobile users   who roam between operators, since prior relationships between the   operators are needed.3.6.  Security   Security has many aspects that need configuration and are therefore   candidates to become autonomic.  On the other hand, it is essential   that a network's central policy be applied strictly for all security   configurations.  As a result, security has largely been based on   centrally imposed configurations.   Many aspects of security depend on policy, for example, password   rules, privacy rules, firewall rulesets, intrusion detection and   prevention settings, VPN configurations, and the choice of   cryptographic algorithms.  Policies are, by definition, human made   and will therefore also persist in an autonomic environment.   However, policies are becoming more high-level, abstracting   addressing, for example, and focusing on the user or application.   The methods to manage, distribute, and apply policy and to monitor   compliance and violations could be autonomic.   Today, many security mechanisms show some autonomic properties.  For   example user authentication via IEEE 802.1x allows automatic mapping   of users after authentication into logical contexts (typically   VLANs).  While today configuration is still very important, the   overall mechanism displays signs of self-adaption to changing   situations.Jiang, et al.                 Informational                     [Page 6]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   BGP Flowspec [RFC5575] allows a partially autonomic threat-defense   mechanism, where threats are identified, the flow information is   automatically distributed, and counter-actions can be applied.   Today, typically a human operator is still in the loop to check   correctness, but over time such mechanisms can become more autonomic.   Negotiation capabilities, present in many security protocols, also   display simple autonomic behaviors.  In this case, a security policy   about algorithm strength can be configured into servers but will   propagate automatically to clients.3.7.  State Synchronization   Another area where autonomic processes between peers are involved is   state synchronization.  In this case, several devices start out with   inconsistent state and go through a peer-to-peer procedure after   which their states are consistent.  Many autonomic or automatic   processes include some degree of implicit state synchronization.   Network time synchronization [RFC5905] is a well-established explicit   example, guaranteeing that a participating node's clock state is   synchronized with reliable time servers within a defined margin of   error, without any overall point of control of the synchronization   process.4.  Current Non-autonomic Behaviors   In current networks, many operations are still heavily dependent on   human intelligence and decision, or on centralized top-down network   management systems.  These operations are the targets of Autonomic   Networking technologies.  The ultimate goal of Autonomic Networking   is to replace human and automated operations by autonomic functions,   so that the networks can run independently without depending on a   human or Network Management System (NMS) for routine details, while   maintaining central control where required.  Of course, there would   still be the absolute minimum of human input required, particularly   during the network-building stage, emergencies, and difficult   troubleshooting.   This section analyzes the existing human and central dependencies in   typical networks and suggests cases where they could, in principle,   be replaced by autonomic behaviors.4.1.  Building a New Network   Building a network requires the operator to analyze the requirements   of the new network, design a deployment architecture and topology,   decide device locations and capacities, set up hardware, design   network services, choose and enable required protocols, configureJiang, et al.                 Informational                     [Page 7]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   each device and each protocol, set up central user authentication and   accounting policies and databases, design and deploy security   mechanisms, etc.   Overall, these jobs are quite complex work that cannot become fully   autonomic in the foreseeable future.  However, part of these jobs may   be able to become autonomic, such as detailed device and protocol   configurations and database population.  The initial network   management policies/behaviors may also be transplanted from other   networks and automatically localized.4.2.  Network Maintenance and Management   Network maintenance and management are very different for ISP   networks and enterprise networks.  ISP networks have to change much   more frequently than enterprise networks, given the fact that ISP   networks have to serve a large number of customers who have very   diversified requirements.  The current rigid model is that network   administrators design a limited number of services for customers to   order.  New requirements of network services may not be able to be   met quickly by human management.  Given a real-time request, the   response must be autonomic, in order to be flexible and quickly   deployed.  However, behind the interface, describing abstracted   network information and user authorization management may have to   depend on human intelligence from network administrators in the   foreseeable future.  User identification integration/consolidation   among networks or network services is another challenge for Autonomic   Network access.  Currently, many end users have to manually manage   their user accounts and authentication information when they switch   among networks or network services.   Classical network maintenance and management mainly handle the   configuration of network devices.  Tools have been developed to   enable remote management and make such management easier.  However,   the decision about each configuration detail depends either on human   intelligence or rigid templates.  Therefore, these are the sources of   all network configuration errors -- the human was wrong, the template   was wrong, or both were wrong.  This is also a barrier to increasing   the utility of network resources, because the human managers cannot   respond quickly enough to network events, such as traffic bursts,   that were not foreseen in the template.  For example, currently, a   light load is often assumed in network design because there is no   mechanism to properly handle a sudden traffic flood.  It is therefore   common to avoid performance collapses caused by traffic overload by   configuring idle resources, with an overprovisioning ratio of at   least 2 being normal [Xiao02].Jiang, et al.                 Informational                     [Page 8]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   There are grounds for concern that the introduction of new, more   flexible, methods of network configuration, typified by Software-   Defined Networking (SDN), will only make the management problem more   complex unless the details are managed automatically or   autonomically.  There is no doubt that SDN creates both the necessity   and the opportunity for automation of configuration management, e.g.,   [Kim13].  This topic is discussed from a service provider viewpoint   in [RFC7149].   Autonomic decision processes for configuration would enable dynamic   management of network resources (by managing resource-relevant   configuration).  Self-adapting network configuration would adjust the   network into the best possible situation; this would prevent   configuration errors from having lasting impact.4.3.  Security Setup   Setting up security for a network generally requires very detailed   human intervention or relies entirely on default configurations that   may be too strict or too risky for the particular situation of the   network.  While some aspects of security are intrinsically top-down   in nature (e.g., broadcasting a specific security policy to all   hosts), others could be self-managed within the network.   In an Autonomic Network, where nodes within a domain have a mutually   verifiable domain identity, security processes could run entirely   automatically.  Nodes could identify each other securely, negotiating   required security settings and even shared keys if needed.  The   locations of the trust anchors (certificate authority, registration   authority), certificate revocation lists, policy server, etc., can be   found by service discovery.  Transactions such as a download of a   certificate revocation list can be authenticated via a common trust   anchor.  Policy distribution can also be entirely automated and   secured via a common trust anchor.   These concepts lead to a network where the intrinsic security is   automatic and applied by default, i.e., a "self-protecting" network.   For further discussion, see [Behringer].4.4.  Troubleshooting and Recovery   Current networks suffer difficulties in locating the cause of network   failures.  Although network devices may issue many warnings while   running, most of them are not sufficiently precise to be identified   as errors.  Some of them are early warnings that would not develop   into real errors.  Others are, in effect, random noise.  During a   major failure, many different devices will issue multiple warnings   within a short time, causing overload for the NMS and the operators.Jiang, et al.                 Informational                     [Page 9]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   However, for many scenarios, human experience is still vital to   identify real issues and locate them.  This situation may be improved   by automatically associating warnings from multiple network devices   together.  Also, introducing automated learning techniques (comparing   current warnings with historical relationships between warnings and   actual faults) could increase the possibility and success rate of   Autonomic Network diagnoses and troubleshooting.   Depending on the network errors, some of them (particularly hardware   failures) may always require human intervention.  However, Autonomic   Network management behavior may help to reduce the impact of errors,   for example, by switching traffic flows around.  Today, this is   usually manual (except for classical routing updates).  Fixing   software failures and configuration errors currently depends on   humans and may even involve rolling back software versions and   rebooting hardware.  Such problems could be autonomically corrected   if there were diagnostics and recovery functions defined in advance   for them.  This would fulfill the concept of self-healing.   Another possible autonomic function is predicting device failures or   overloads before they occur.  A device could predict its own failure   and warn its neighbors, or a device could predict its neighbor's   failure.  In either case, an Autonomic Network could respond as if   the failure had already occurred by routing around the problem and   reporting the failure, with no disturbance to users.  The criteria   for predicting failure could be temperature, battery status, bit   error rates, etc.  The criteria for predicting overload could be   increasing load factor, latency, jitter, congestion loss, etc.5.  Features Needed by Autonomic Networks   There are innumerable properties of network devices and end systems   that today need to be configured either manually, by scripting, or by   using a management protocol such as the Network Configuration   Protocol (NETCONF) [RFC6241].  In an Autonomic Network, all of these   would need to either have satisfactory default values or be   configured automatically.  Some examples are parameters for tunnels   of various kinds, flows (in an SDN context), quality of service,   service function chaining, energy management, system identification,   and NTP configuration, but the list is endless.   The task of Autonomic Networking is to incrementally build up   individual autonomic processes that could progressively be combined   to respond to every type of network event.  Building on the preceding   background information, and on the reference model in [RFC7575], this   section outlines the gaps and missing features in general terms and,   in some cases, mentions general design principles that should apply.Jiang, et al.                 Informational                    [Page 10]

RFC 7576            Autonomic Networking Gap Analysis          June 20155.1.  More Coordination among Devices or Network Partitions   Network services are dependent on a number of devices and parameters   to be in place in a certain order.  For example, after a power   failure, a coordinated sequence of "return to normal" operations is   desirable (e.g., switches and routers first, DNS servers second,   etc.).  Today, the correct sequence of events is either known only by   a human administrator or automated in a central script.  In a truly   Autonomic Network, elements should understand their dependencies and   be able to resolve them locally.   In order to make right or good decisions autonomically, the network   devices need to know more information than just reachability   (routing) information from the relevant or neighbor devices.  Devices   must be able to derive, for themselves, the dependencies between such   information and configurations.   There are therefore increased requirements for horizontal information   exchange in the networks.  Particularly, three types of interaction   among peer network devices are needed for autonomic decisions:   discovery (to find neighbors and peers), synchronization (to agree on   network status), and negotiation (when things need to be changed).   Thus, there is a need for reusable discovery, synchronization, and   negotiation mechanisms that would support the discovery of many   different types of device, the synchronization of many types of   parameter, and the negotiation of many different types of objective.5.2.  Reusable Common Components   Elements of autonomic functions already exist today, within many   different protocols.  However, all such functions have their own   discovery, transport, messaging, and security mechanisms as well as   non-autonomic management interfaces.  Each protocol has its own   version of the above-mentioned functions to serve specific and narrow   purposes.  It is often difficult to extend an existing protocol to   serve different purposes.  Therefore, in order to provide the   reusable discovery, synchronization, and negotiation mechanisms   mentioned above, it is desirable to develop a set of reusable common   protocol components for Autonomic Networking.  These components   should be:   o  Able to identify other devices, users, and processes securely.   o  Able to automatically secure operations, based on the above      identity scheme.   o  Able to manage any type of information and information flows.Jiang, et al.                 Informational                    [Page 11]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   o  Able to discover peer devices and services for various Autonomic      Service Agents (or autonomic functions).   o  Able to support closed-loop operations when needed to provide      self-managing functions involving more than one device.   o  Separable from the specific Autonomic Service Agents (or autonomic      functions).   o  Reusable by other autonomic functions.5.3.  Secure Control Plane   The common components will, in effect, act as a control plane for   autonomic operations.  This control plane might be implemented in-   band as functions of the target network, in an overlay network, or   even out-of-band in a separate network.  Autonomic operations will be   capable of changing how the network operates and allocating resources   without human intervention or knowledge, so it is essential that they   are secure.  Therefore, the control plane must be designed to be   secure against forged autonomic operations and man-in-the middle   attacks and as secure as reasonably possible against denial-of-   service attacks.  It must be decided whether the control plane needs   to be resistant to unwanted monitoring, i.e., whether encryption is   required.5.4.  Less Configuration   Many existing protocols have been defined to be as flexible as   possible.  Consequently, these protocols need numerous initial   configurations to start operations.  There are choices and options   that are irrelevant in any particular case, some of which target   corner cases.  Furthermore, in protocols that have existed for years,   some design considerations are no longer relevant, since the   underlying hardware technologies have evolved meanwhile.  To   appreciate the scale of this problem, consider that more than 160   DHCP options have been defined for IPv4.  Even sample router   configuration files readily available online contain more than 200   lines of commands.  There is therefore considerable scope for   simplifying the operational tools for configuration of common   protocols, even if the underlying protocols themselves cannot be   simplified.   From another perspective, the deep reason why human decisions are   often needed mainly results from the lack of information.  When a   device can collect enough information horizontally from other   devices, it should be able to decide many parameters by itself,   instead of receiving them from top-down configuration.Jiang, et al.                 Informational                    [Page 12]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   It is desired that top-down management is reduced in Autonomic   Networking.  Ideally, only the abstract Intent is needed from the   human administrators.  Neither users nor administrators should need   to create and maintain detailed policies and profiles; if they are   needed, they should be built autonomically.  The local parameters   should be decided by distributed Autonomic Nodes themselves, either   from historic knowledge, analytics of current conditions, closed   logical decision loops, or a combination of all.5.5.  Forecasting and Dry Runs   In a conventional network, there is no mechanism for trying something   out safely, which means that configuration changes have to be   designed in the abstract and their probable effects have to be   estimated theoretically.  In principle, an alternative to this would   be to test the changes on a complete and realistic network simulator.   However, this is a practical impossibility for a large network that   is constantly changing, even if an accurate simulation could be   performed.  There is therefore a risk that applying changes to a   running network will cause a failure of some kind.  An autonomic   network could fill this gap by supporting a closed loop "dry run"   mode in which each configuration change could be tested out   dynamically in the control plane without actually affecting the data   plane.  If the results are satisfactory, the change could be made   live on the running network.  If there is a consistency problem such   as overcommitment of resources or incompatibility with another   configuration setting, the change could be rolled back dynamically   with no impact on traffic or users.5.6.  Benefit from Knowledge   The more knowledge and experience we have, the better decisions we   can make.  It is the same for networks and network management.  When   one component in the network lacks knowledge that affects what it   should do, and another component has that knowledge, we usually rely   on a human operator or a centralized management tool to convey the   knowledge.   Up to now, the only available network knowledge is usually the   current network status inside a given device or relevant current   status from other devices.   However, historic knowledge is very helpful to make correct   decisions, in particular, to reduce network oscillation or to manage   network resources over time.  Transplantable knowledge from other   networks can be helpful to initially set up a new network or newJiang, et al.                 Informational                    [Page 13]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   network devices.  Knowledge of relationships between network events   and network configuration may help a network to decide the best   parameters according to real performance feedback.   In addition to such historic knowledge, powerful data analytics of   current network conditions may also be a valuable source of knowledge   that can be exploited directly by Autonomic Nodes.6.  Security Considerations   This document is focused on what is missing to allow autonomic   network configuration, including security settings, of course.   Therefore, it does not itself create any new security issues.  It is   worth underlining that autonomic technology must be designed with   strong security properties from the start, since a network with   vulnerable autonomic functions would be at great risk.7.  Informative References   [Behringer]              Behringer, M., Pritikin, M., and S. Bjarnason, "Making The              Internet Secure By Default", Work in Progress,draft-behringer-default-secure-00, January 2014.   [Kim13]    Kim, H. and N. Feamster, "Improving Network Management              with Software Defined Networking", IEEE Communications              Magazine, pages 114-119, February 2013.   [Pfister]  Pfister, P., Paterson, B., and J. Arkko, "Distributed              Prefix Assignment Algorithm", Work in Progress,draft-ietf-homenet-prefix-assignment-07, June 2015.   [RFC1661]  Simpson, W., Ed., "The Point-to-Point Protocol (PPP)",              STD 51,RFC 1661, DOI 10.17487/RFC1661, July 1994,              <http://www.rfc-editor.org/info/rfc1661>.   [RFC1994]  Simpson, W., "PPP Challenge Handshake Authentication              Protocol (CHAP)",RFC 1994, DOI 10.17487/RFC1994, August              1996, <http://www.rfc-editor.org/info/rfc1994>.   [RFC2131]  Droms, R., "Dynamic Host Configuration Protocol",RFC 2131, DOI 10.17487/RFC2131, March 1997,              <http://www.rfc-editor.org/info/rfc2131>.   [RFC2136]  Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound,              "Dynamic Updates in the Domain Name System (DNS UPDATE)",RFC 2136, DOI 10.17487/RFC2136, April 1997,              <http://www.rfc-editor.org/info/rfc2136>.Jiang, et al.                 Informational                    [Page 14]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,              "Remote Authentication Dial In User Service (RADIUS)",RFC 2865, DOI 10.17487/RFC2865, June 2000,              <http://www.rfc-editor.org/info/rfc2865>.   [RFC2866]  Rigney, C., "RADIUS Accounting",RFC 2866,              DOI 10.17487/RFC2866, June 2000,              <http://www.rfc-editor.org/info/rfc2866>.   [RFC3315]  Droms, R., Ed., Bound, J., Volz, B., Lemon, T., Perkins,              C., and M. Carney, "Dynamic Host Configuration Protocol              for IPv6 (DHCPv6)",RFC 3315, DOI 10.17487/RFC3315, July              2003, <http://www.rfc-editor.org/info/rfc3315>.   [RFC3633]  Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic              Host Configuration Protocol (DHCP) version 6",RFC 3633,              DOI 10.17487/RFC3633, December 2003,              <http://www.rfc-editor.org/info/rfc3633>.   [RFC4861]  Narten, T., Nordmark, E., Simpson, W., and H. Soliman,              "Neighbor Discovery for IP version 6 (IPv6)",RFC 4861,              DOI 10.17487/RFC4861, September 2007,              <http://www.rfc-editor.org/info/rfc4861>.   [RFC4862]  Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless              Address Autoconfiguration",RFC 4862,              DOI 10.17487/RFC4862, September 2007,              <http://www.rfc-editor.org/info/rfc4862>.   [RFC5575]  Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,              and D. McPherson, "Dissemination of Flow Specification              Rules",RFC 5575, DOI 10.17487/RFC5575, August 2009,              <http://www.rfc-editor.org/info/rfc5575>.   [RFC5905]  Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,              "Network Time Protocol Version 4: Protocol and Algorithms              Specification",RFC 5905, DOI 10.17487/RFC5905, June 2010,              <http://www.rfc-editor.org/info/rfc5905>.   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,              and A. Bierman, Ed., "Network Configuration Protocol              (NETCONF)",RFC 6241, DOI 10.17487/RFC6241, June 2011,              <http://www.rfc-editor.org/info/rfc6241>.   [RFC6418]  Blanchet, M. and P. Seite, "Multiple Interfaces and              Provisioning Domains Problem Statement",RFC 6418,              DOI 10.17487/RFC6418, November 2011,              <http://www.rfc-editor.org/info/rfc6418>.Jiang, et al.                 Informational                    [Page 15]

RFC 7576            Autonomic Networking Gap Analysis          June 2015   [RFC6762]  Cheshire, S. and M. Krochmal, "Multicast DNS",RFC 6762,              DOI 10.17487/RFC6762, February 2013,              <http://www.rfc-editor.org/info/rfc6762>.   [RFC7010]  Liu, B., Jiang, S., Carpenter, B., Venaas, S., and W.              George, "IPv6 Site Renumbering Gap Analysis",RFC 7010,              DOI 10.17487/RFC7010, September 2013,              <http://www.rfc-editor.org/info/rfc7010>.   [RFC7136]  Carpenter, B. and S. Jiang, "Significance of IPv6              Interface Identifiers",RFC 7136, DOI 10.17487/RFC7136,              February 2014, <http://www.rfc-editor.org/info/rfc7136>.   [RFC7149]  Boucadair, M. and C. Jacquenet, "Software-Defined              Networking: A Perspective from within a Service Provider              Environment",RFC 7149, DOI 10.17487/RFC7149, March 2014,              <http://www.rfc-editor.org/info/rfc7149>.   [RFC7575]  Behringer, M., Pritikin, M., Bjarnason, S., Clemm, A.,              Carpenter, B., Jiang, S., and L. Ciavaglia, "Autonomic              Networking: Definitions and Design Goals",RFC 7575,              DOI 10.17487/RFC7575, June 2015,              <http://www.rfc-editor.org/info/rfc7575>.   [Xiao02]   Xiao, X., Telkamp, T., Fineberg, V., Chen, C., and L. Ni,              "A Practical Approach for Providing QoS in the Internet              Backbone", IEEE Communications Magazine, pages 56-62,              December 2002.Jiang, et al.                 Informational                    [Page 16]

RFC 7576            Autonomic Networking Gap Analysis          June 2015Acknowledgements   The authors would like to acknowledge the valuable comments made by   participants in the IRTF Network Management Research Group.  Reviews   by Kevin Fall and Rene Struik were especially helpful.Authors' Addresses   Sheng Jiang   Huawei Technologies Co., Ltd   Q14, Huawei Campus, No.156 Beiqing Road   Hai-Dian District, Beijing, 100095   China   EMail: jiangsheng@huawei.com   Brian Carpenter   Department of Computer Science   University of Auckland   PB 92019   Auckland  1142   New Zealand   EMail: brian.e.carpenter@gmail.com   Michael H. Behringer   Cisco Systems   Building D, 45 Allee des Ormes   Mougins 06250   France   EMail: mbehring@cisco.comJiang, et al.                 Informational                    [Page 17]

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