Internet DRAFT - draft-irtf-nmrg-an-gap-analysis
draft-irtf-nmrg-an-gap-analysis
Network Management Research Group S. Jiang
Internet-Draft Huawei Technologies Co., Ltd
Intended status: Informational B. Carpenter
Expires: November 2, 2015 Univ. of Auckland
M. Behringer
Cisco Systems
May 1, 2015
General Gap Analysis for Autonomic Networking
draft-irtf-nmrg-an-gap-analysis-06
Abstract
This document is a product of the IRTF's Network Management Research
Group. It 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 a background by reviewing the
current status of autonomic aspects of IP networks and the extent to
which current network management depends on centralisation and human
administrators. Finally the document outlines the general features
missing from current network abilities that are needed in the ideal
Autonomic Network concept.
Status of This Memo
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This Internet-Draft will expire on November 2, 2015.
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Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Provisions Relating to IETF Documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Automatic and Autonomic Aspects of Current IP Networks . . . 3
3.1. IP Address Management and DNS . . . . . . . . . . . . . . 3
3.2. Routing . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.3. Configuration of Default Router in a Host . . . . . . . . 5
3.4. Hostname Lookup . . . . . . . . . . . . . . . . . . . . . 5
3.5. User Authentication and Accounting . . . . . . . . . . . 6
3.6. Security . . . . . . . . . . . . . . . . . . . . . . . . 6
3.7. State Synchronization . . . . . . . . . . . . . . . . . . 7
4. Current Non-Autonomic Behaviors . . . . . . . . . . . . . . . 7
4.1. Building a New Network . . . . . . . . . . . . . . . . . 7
4.2. Network Maintenance and Management . . . . . . . . . . . 8
4.3. Security Setup . . . . . . . . . . . . . . . . . . . . . 9
4.4. Troubleshooting and Recovery . . . . . . . . . . . . . . 9
5. Features Needed by Autonomic Networks . . . . . . . . . . . . 10
5.1. More Coordination among Devices or Network Partitions . . 11
5.2. Reusable Common Components . . . . . . . . . . . . . . . 11
5.3. Secure Control Plane . . . . . . . . . . . . . . . . . . 12
5.4. Less Configuration . . . . . . . . . . . . . . . . . . . 12
5.5. Forecasting and Dry Runs . . . . . . . . . . . . . . . . 13
5.6. Benefit from Knowledge . . . . . . . . . . . . . . . . . 13
6. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. Change log [RFC Editor: Please remove] . . . . . . . . . . . 14
10. Informative References . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
The general goals and relevant definitions for Autonomic Networking
are discussed in [I-D.irtf-nmrg-autonomic-network-definitions]. 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,
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often involving human administrators and a considerable degree of
centralisation. 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 trouble-shooting, 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
which would allow autonomic behaviours to be added throughout the
Internet.
2. Terminology
The terminology defined in
[I-D.irtf-nmrg-autonomic-network-definitions] 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,
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
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[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 synthesise DNS names even for hosts that only played the
role of clients. Therefore, it became necessary to synchronise DHCP
server tables with forward and reverse DNS. For this reason,
Internet Protocol address management tools emerged, as discussed for
the case of renumbering in [RFC7010]. These are, however,
centralised solutions that do not exhibit autonomic properties as
defined in [I-D.irtf-nmrg-autonomic-network-definitions].
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
[I-D.ietf-homenet-prefix-assignment]. Still further away is
autonomic assignment and delegation of routeable 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].
3.2. 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
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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 this 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 host names 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, need to be configured with the appropriate DNS
server addresses. Additionally, some networks deploy Multicast DNS
[RFC6762] locally to provide additional automation of the name space.
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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 set up
of dedicated physical links with users. Automated user
authentication was introduced by 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 AAA server automatically. This mechanism enables
business models with charging based on traffic based or time based
usage. However, the management of user authentication information
remains manual 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 should 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 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.
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.
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Negotiation capabilities, present in many security protocols, also
display simple autonomic behaviours. 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 centralised 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 NMS system 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, and during emergencies and difficult trouble-
shooting.
This section analyzes the existing human and central dependencies in
typical current 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, configure
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
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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 manages 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. One or the other of these is
therefore the source of all network configuration errors - either the
human was wrong, or the template was wrong (or both). 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].
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.,
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[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, which also prevents
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
location of trust anchors (certificate authority, registration
authority), certificate revocation lists, policy server, etc., can be
found by service discovery. Transactions such as a certificate
revocation list download 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 [I-D.behringer-default-secure]
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. 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
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actual faults) could increase the possibility and success rate of
Autonomic Network diagnoses and troubleshooting.
Depending on the network errors, some of them may always require
human interventions, particularly for hardware failures. 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 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
[I-D.irtf-nmrg-autonomic-network-definitions], this section outlines
the gaps and missing features in general terms, and in some cases
mentions general design principles that should apply.
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5.1. 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. There
are dependencies between such information and configurations, which
devices must be able to derive for themselves.
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 neighbours 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, which 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 mechanism
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.
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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 otions have been defined for IPv4. Even sample router
configuration files readily available on line 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 result 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.
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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. That 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 which
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 over-commitment 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 take. 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 centralised 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 new
network devices. Knowledge of relationships between network events
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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 of course security settings.
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. IANA Considerations
This memo includes no request to IANA.
8. Acknowledgements
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.
This document was produced using the xml2rfc tool [RFC2629].
9. Change log [RFC Editor: Please remove]
draft-irtf-nmrg-an-gap-analysis-06: RFC Editor comments actioned,
2015-05-01.
draft-irtf-nmrg-an-gap-analysis-05: IESG Review comments actioned,
2015-03-23.
draft-irtf-nmrg-an-gap-analysis-04: Additional IRSG Review comments
actioned, 2015-03-04.
draft-irtf-nmrg-an-gap-analysis-03: IRSG Review comments actioned,
2014-12-11.
draft-irtf-nmrg-an-gap-analysis-02: Review comments actioned,
2014-10-02.
draft-irtf-nmrg-an-gap-analysis-01: RG comments added and more
content in "Approach toward Autonomy" section, 2014-08-30.
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draft-irtf-nmrg-an-gap-analysis-00: RG comments added, 2014-04-02.
draft-jiang-nmrg-an-gap-analysis-00: original version, 2014-02-14.
10. Informative References
[I-D.behringer-default-secure]
Behringer, M., Pritikin, M., and S. Bjarnason, "Making The
Internet Secure By Default", draft-behringer-default-
secure-00 (work in progress), January 2014.
[I-D.ietf-homenet-prefix-assignment]
Pfister, P., Paterson, B., and J. Arkko, "Distributed
Prefix Assignment Algorithm", draft-ietf-homenet-prefix-
assignment-05 (work in progress), April 2015.
[I-D.irtf-nmrg-autonomic-network-definitions]
Behringer, M., Pritikin, M., Bjarnason, S., Clemm, A.,
Carpenter, B., Jiang, S., and L. Ciavaglia, "Autonomic
Networking - Definitions and Design Goals", draft-irtf-
nmrg-autonomic-network-definitions-07 (work in progress),
March 2015.
[Kim13] Kim, H. and N. Feamster, "Improving Network Management
with Software Defined Networking", IEEE Communications
Magazine, Pages 114-119, February 2013.
[RFC1661] Simpson, W., "The Point-to-Point Protocol (PPP)", STD 51,
RFC 1661, July 1994.
[RFC1994] Simpson, W., "PPP Challenge Handshake Authentication
Protocol (CHAP)", RFC 1994, August 1996.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC
2131, March 1997.
[RFC2136] Vixie, P., Thomson, S., Rekhter, Y., and J. Bound,
"Dynamic Updates in the Domain Name System (DNS UPDATE)",
RFC 2136, April 1997.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)", RFC
2865, June 2000.
[RFC2866] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.
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[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic
Host Configuration Protocol (DHCP) version 6", RFC 3633,
December 2003.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, August 2009.
[RFC5905] Mills, D., Martin, J., Burbank, J., and W. Kasch, "Network
Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, June 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)", RFC
6241, June 2011.
[RFC6418] Blanchet, M. and P. Seite, "Multiple Interfaces and
Provisioning Domains Problem Statement", RFC 6418,
November 2011.
[RFC6762] Cheshire, S. and M. Krochmal, "Multicast DNS", RFC 6762,
February 2013.
[RFC7010] Liu, B., Jiang, S., Carpenter, B., Venaas, S., and W.
George, "IPv6 Site Renumbering Gap Analysis", RFC 7010,
September 2013.
[RFC7136] Carpenter, B. and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, February 2014.
[RFC7149] Boucadair, M. and C. Jacquenet, "Software-Defined
Networking: A Perspective from within a Service Provider
Environment", RFC 7149, March 2014.
[Xiao02] Xiao, X. and others, "A Practical Approach for Providing
QoS in the Internet Backbone", IEEE Communications
Magazine, Pages 56-59, December 2002.
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Authors' Addresses
Sheng Jiang
Huawei Technologies Co., Ltd
Q14, Huawei Campus, No.156 Beiqing Road
Hai-Dian District, Beijing, 100095
P.R. 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.com
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