ANIMA WG M. Behringer, Ed.
Internet-Draft S. Bjarnason
Intended status: Standards Track Balaji. BL
Expires: February 18, 2016 T. Eckert
Cisco Systems
August 17, 2015
An Autonomic Control Plane
draft-ietf-anima-autonomic-control-plane-00
Abstract
Autonomic functions need a control plane to communicate, which
depends on some addressing and routing. This Autonomic Control Plane
should ideally be self-managing, and as independent as possible of
configuration. One application is a "virtual out of band channel"
for communications over a network that is not configured or mis-
configured. This document describes requirements and implementation
options for an "Autonomic Control Plane".
Status of This Memo
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on February 18, 2016.
Copyright Notice
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to this document. Code Components extracted from this document must
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Use Cases for an Autonomic Control Plane . . . . . . . . . . 4
2.1. An Infrastructure for Autonomic Functions . . . . . . . . 4
2.2. Secure Bootstrap over an Unconfigured Network . . . . . . 4
2.3. Data Plane Independent Permanent Reachability . . . . . . 4
3. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5. Self-Creation of an Autonomic Control Plane . . . . . . . . . 7
5.1. Preconditions . . . . . . . . . . . . . . . . . . . . . . 7
5.2. Adjacency Discovery . . . . . . . . . . . . . . . . . . . 8
5.3. Authenticating Neighbors . . . . . . . . . . . . . . . . 8
5.4. Capability Negotiation . . . . . . . . . . . . . . . . . 9
5.5. Channel Establishment . . . . . . . . . . . . . . . . . . 9
5.6. Context Separation . . . . . . . . . . . . . . . . . . . 10
5.7. Addressing inside the ACP . . . . . . . . . . . . . . . . 10
5.8. Routing in the ACP . . . . . . . . . . . . . . . . . . . 11
5.9. Connecting a Controller / NMS system . . . . . . . . . . 11
6. Self-Healing Properties . . . . . . . . . . . . . . . . . . . 12
7. Self-Protection Properties . . . . . . . . . . . . . . . . . 13
8. The Administrator View . . . . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 14
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15
12. Change log [RFC Editor: Please remove] . . . . . . . . . . . 15
12.1. Initial version . . . . . . . . . . . . . . . . . . . . 15
12.2. draft-behringer-anima-autonomic-control-plane-00 . . . . 15
12.3. draft-behringer-anima-autonomic-control-plane-01 . . . . 15
12.4. draft-behringer-anima-autonomic-control-plane-02 . . . . 16
12.5. draft-behringer-anima-autonomic-control-plane-03 . . . . 16
12.6. draft-ietf-anima-autonomic-control-plane-00 . . . . . . 16
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Autonomic Networking is a concept of self-management: Autonomic
functions self-configure, and negotiate parameters and settings
across the network. [RFC7575] defines the fundamental ideas and
design goals of Autonomic Networking. A gap analysis of Autonomic
Networking is given in [RFC7576]. The reference architecture for
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Autonomic Networking in the IETF is currently being defined in the
document [I-D.behringer-anima-reference-model]
Autonomic functions need a stable and robust infrastructure to
communicate on. This infrastructure should be as robust as possible,
and it should be re-usable by all autonomic functions. [RFC7575]
calls it the "Autonomic Control Plane". This document defines the
requirements and implementation options of an Autonomic Control
Plane.
Today, the management and control plane of networks typically runs in
the global routing table, which is dependent on correct configuration
and routing. Misconfigurations or routing problems can therefore
disrupt management and control channels. Traditionally, an out of
band network has been used to recover from such problems, or
personnel is sent on site to access devices through console ports.
However, both options are operationally expensive.
In increasingly automated networks either controllers or distributed
autonomic service agents in the network require a control plane which
is independent of the network they manage, to avoid impacting their
own operations.
This document describes options for a self-forming, self-managing and
self-protecting "Autonomic Control Plane" (ACP) which is inband on
the network, yet as independent as possible of configuration,
addressing and routing problems (for details how this achieved, see
Section 5). It therefore remains operational even in the presence of
configuration errors, addressing or routing issues, or where policy
could inadvertently affect control plane connectivity. The Autonomic
Control Plane serves several purposes at the same time:
o Autonomic functions communicate over the ACP.
o An operator can use it to log into remote devices, even if the
data plane is misconfigured or unconfigured.
o A controller or network management system can use it to securely
bootstrap network devices in remote locations, even if the network
in between is not yet configured; no data-plane dependent
bootstrap configuration is required. An example of such a secure
bootstrap process is described in
[I-D.pritikin-anima-bootstrapping-keyinfra]
o Devices can use the ACP for direct decentralised communications,
such as negotiations or discovery. The ACP therefore supports
directly Autonomic Networking functions, as described in
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[I-D.behringer-anima-reference-model]. For example, GDNP
[I-D.carpenter-anima-gdn-protocol] can run inside the ACP.
This document describes some use cases for the ACP in Section 2, it
defines the requirements in Section 3, Section 4 gives an overview
how an Autonomic Control Plane is constructed, and in Section 5 the
detailed process is explained. The document "Autonomic Network
Stable Connectivity" [I-D.eckert-anima-stable-connectivity] describes
how the ACP can be used to provide stable connectivity for OAM
applications. It also explains on how existing management solutions
can leverage the ACP in parallel with traditional management models,
when to use the ACP versus the data plane, how to integrate IPv4
based management, etc.
2. Use Cases for an Autonomic Control Plane
2.1. An Infrastructure for Autonomic Functions
Autonomic Functions need a stable infrastructure to run on, and all
autonomic functions should use the same infrastructure to minimise
the complexity of the network. This way, there is only need for a
single discovery mechanism, a single security mechanism, and other
process that distributed functions require.
2.2. Secure Bootstrap over an Unconfigured Network
Today, bootstrapping a new device typically requires all devices
between a controlling node (such as an SDN controller) and the new
device to be completely and correctly addressed, configured and
secured. Therefore, bootstrapping a network happens in layers around
the controller. Without console access (for example through an out
of band network) it is not possible today to make devices securely
reachable before having configured the entire network between.
With the ACP, secure bootstrap of new devices can happen without
requiring any configuration on the network. A new device can
automatically be bootstrapped in a secure fashion and be deployed
with a domain certificate. This does not require any configuration
on intermediate nodes, because they can communicate through the ACP.
2.3. Data Plane Independent Permanent Reachability
Today, most critical control plane protocols and network management
protocols are running in the data plane (global routing table) of the
network. This leads to undesirable dependencies between control and
management plane on one side and the data plane on the other: Only if
the data plane is operational, will the other planes work as
expected.
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Data plane connectivity can be affected by errors and faults, for
example certain AAA misconfigurations can lock an administrator out
of a device; routing or addressing issues can make a device
unreachable; shutting down interfaces over which a current management
session is running can lock an admin irreversibly out of the device.
Traditionally only console access can help recover from such issues.
Data plane dependencies also affect NOC/SDN controller applications:
Certain network changes are today hard to operate, because the change
itself may affect reachability of the devices. Examples are address
or mask changes, routing changes, or security policies. Today such
changes require precise hop-by-hop planning.
The ACP provides reachability that is largely independent of the data
plane, which allows control plane and management plane to operate
more robustly:
o For management plane protocols, the ACP provides the functionality
of a "Virtual-out-of-band (VooB) channel", by providing
connectivity to all devices regardless of their configuration or
global routing table.
o For control plane protocols, the ACP allows their operation even
when the data plane is temporarily faulty, or during transitional
events, such as routing changes, which may affect the control
plane at least temporarily. This is specifically important for
autonomic service agents, which could affect data plane
connectivity.
The document "Autonomic Network Stable Connectivity"
[I-D.eckert-anima-stable-connectivity] explains the use cases for the
ACP in significantly more detail and explains how the ACP can be used
in practical network operations.
3. Requirements
The Autonomic Control Plane has the following requirements:
1. The ACP SHOULD provide robust connectivity: As far as possible,
it should be independent of configured addressing, configuration
and routing. (2 and 3 build on this requirement, but also have
value on their own)
2. The ACP MUST have a separate address space from the data plane.
Reason: traceability, debug-ability, separation from data plane,
security (can block at edge)
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3. The ACP MUST use autonomically managed address space. Reason:
easy bootstrap and setup ("autonomic"); robustness (admin can't
mess things up so easily). ULA seems like a good choice for 1
and 2.
4. The ACP MUST be generic. Usable by all the functions and
protocols of the AN infrastructure. MUST NOT be tied to a
particular protocol.
5. The ACP MUST provide security: Messages coming through the ACP
MUST be authenticated to be from a trusted node, and SHOULD (very
strong SHOULD) be encrypted.
The default mode of operation of the ACP is hop-by-hop, because this
interaction can be built on IPv6 link local addressing, which is
autonomic, and has no dependency on configuration (requirement 1).
It may be necessary to have end-to-end connectivity in some cases,
for example to provide an end-to-end security association for some
protocols. This is possible, but then has a dependency on routable
address space.
4. Overview
The Autonomic Control Plane is constructed in the following way (for
details, see Section 5):
o Each autonomic node creates a virtual routing and forwarding (VRF)
instance, or a similar virtual context.
o When an autonomic node discovers another autonomic node from the
same domain, it authenticates that node and negotiates a secure
tunnel to it. These tunnels are placed into the previously set up
VRF. This creates an overlay network with hop-by-hop tunnels.
o Inside the ACP VRF, each node sets up a loopback interface with a
ULA IPv6 address.
o Each node runs a lightweight routing protocol, to announce
reachability of the loopback addresses inside the ACP.
o NMS systems or controllers have to be manually connected into the
ACP.
o None of the above operations is reflected in the configuration of
the device.
The following figure illustrates the ACP.
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autonomic node 1 autonomic node 2
................... ...................
secure . . secure . . secure
tunnel : +-----------+ : tunnel : +-----------+ : tunnel
..--------| ACP VRF |---------------------| ACP VRF |---------..
: / \ / \ <--routing--> / \ / \ :
: \ / \ / \ / \ / :
..--------| loopback |---------------------| loopback |---------..
: +-----------+ : : +-----------+ :
: : : :
: data plane :...............: data plane :
: : link : :
:.................: :.................:
Figure 1
The resulting overlay network is normally based exclusively on hop-
by-hop tunnels. This is because addressing used on links is IPv6
link local addressing, which does not require any prior set-up. This
way the ACP can be built even if there is no configuration on the
devices, or if the data plane has issues such as addressing or
routing problems.
An alternative ACP design can be achieved without the VRFs. In this
case, the autonomic virtual addresses are part of the data plane, and
subject to routing, filtering, QoS, etc on the data plane. The
secure tunnels are in this case used by traffic to and from the
autonomic address space. They are still required to provide the
authentication function for all autonomic packets.
5. Self-Creation of an Autonomic Control Plane
This section describes the steps to set up an Autonomic Control
Plane, and highlights the key properties which make it
"indestructible" against many inadvert changes to the data plane, for
example caused by misconfigurations.
5.1. Preconditions
Each autonomic device has a globally unique domain certificate, with
which it can cryptographically assert its membership of the domain.
The document [I-D.pritikin-anima-bootstrapping-keyinfra] describes
how a domain certificate can be automatically and securely derived
from a vendor specific Unique Device Identifier (UDI) or IDevID
certificate. (Note the UDI used in this document is NOT the UUID
specified in [RFC4122].)
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5.2. Adjacency Discovery
Adjacency discovery exchanges identity information about neighbors,
either the UDI or, if present, the domain certificate (see
Section 5.1. This document assumes the existence of a domain
certificate.
Adjacency discovery provides a table of information of adjacent
neighbors. Each neighbor is identified by a globally unique device
identifier (UDI).
The adjacency table contains the following information about the
adjacent neighbors.
o Globally valid Unique device identifier (UDI).
o Link Local IPv6 address with its scope.
o Trust information: The certificate chain, if available.
o Validity of the trust (once validated, see next section).
Adjacency discovery can populate this table by several means. One
such mechanism is to discover using link local multicast probes,
which has no dependency on configured addressing and is preferable in
an autonomic network.
The "Generic Discovery and Negotiation Protocol" GDNP described in
[I-D.carpenter-anima-gdn-protocol] is a possible candidate protocol
to meet the requirements for Adjacency Discovery described here.
5.3. Authenticating Neighbors
Each neighbor in the adjacency table is authenticated. The result of
the authentication of the neighbor information is stored in the
adjacency table. We distinguish the following cases:
o Inside the domain: If the domain certificate presented is
validated (including proof of possession of the corresponding
private key) to be in the same domain as that of the autonomic
entity then the neighbor is deemed to be inside the autonomic
domain. Only entities inside the autonomic domain will by default
be able to establish the autonomic control plane. Alternatively,
policy can define whether to simply trust devices with the same
trust anchor. An ACP channel will be established.
o Outside the domain: If there is no domain certificate presented by
the neighbor, or if the domain certificate presented is invalid or
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expired, then the neighbor is deemed to be outside the autonomic
domain. No ACP channel will be established.
Certificate management questions such as enrolment, revocation,
renewal, etc, are not discussed in this draft. Please refer to
[I-D.pritikin-anima-bootstrapping-keyinfra] for more details.
5.4. Capability Negotiation
Autonomic devices have different capabilities based on the type of
device and where it is deployed. To establish a trusted secure
communication channel, devices must be able to negotiate with each
neighbor a set of parameters for establishing the communication
channel, most notably channel type and security type. the
communication channel, most notably channel type and security type.
The channel type could be any tunnel mechanism that is feasible
between two adjacent neighbors, for example a GRE tunnel. The
security type could be any of the channel protection mechanism that
is available between two adjacent neighbors on a given channel type,
for example TLS, DTLS or IPsec. The establishment of the autonomic
control plane can happen after the channel type and security type is
negotiated.
The "Generic Discovery and Negotiation Protocol GDNP described in
[I-D.carpenter-anima-gdn-protocol] is a possible candidate protocol
to meet the requirements for capability negotiation described here.
5.5. Channel Establishment
After authentication and capability negotiation autonomic nodes
establish a secure channel towards their direct AN neighbors with the
above negotiated parameters. In order to be independent of
configured link addresses, these channels can be implemented in
several ways:
o As a secure IP tunnel (e.g., IPsec, DTLS, TLS, etc.), using IPv6
link local addresses between two adjacent neighbors. This way,
the ACP tunnels are independent of correct network wide routing.
They also do not require larger than link local scope addresses,
which would normally need to be configured or maintained. Each AN
node MUST support this function.
o L2 separation, for example via a separate 802.1q tag for ACP
traffic. This even further reduces dependency against the data
plane (not even IPv6 link-local there required), but may be harder
to implement.
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Since channels are established between adjacent neighbors, the
resulting overlay network does hop by hop encryption. Each node
decrypts incoming traffic from the ACP, and encrypts outgoing traffic
to its neighbors in the ACP. Routing is discussed in Section 5.8.
If two nodes are connected via several links, the ACP SHOULD be
established on every link, but it is possible to establish the ACP
only on a sub-set of links. Having an ACP channel on every link has
a number of advantages, for example it allows for a faster failover
in case of link failure, and it reflects the physical topology more
closely. Using a subset of links (for example, a single link),
reduces resource consumption on the devices, because state needs to
be kept per ACP channel.
5.6. Context Separation
The ACP is in a separate context from the normal data plane of the
device. This context includes the ACP channels IPv6 forwarding and
routing as well as any required higher layer ACP functions.
In classical network device platforms, a dedicated so called "Virtual
routing and forwarding instance" (VRF) is one logical implementation
option for the ACP. If possible by the platform SW architecture,
separation options that minimize shared components are preferred.
The context for the ACP needs to be established automatically during
bootstrap of a device and - as necessitated by the implementation
option be protected from being modified unintential from data plane
configuration.
In addition this provides for security, because the ACP is not
reachable from the global routing table. Also, configuration errors
from the data plane setup do not affect the ACP.
5.7. Addressing inside the ACP
The channels explained above only establish communication between two
adjacent neighbors. In order for the communication to happen across
multiple hops, the autonomic control plane requires internal network
wide valid addresses and routing. Each autonomic node must create a
loopback interface with a network wide unique address inside the ACP
context mentioned in Section 5.6.
We suggest to create network wide Unique Local Addresses (ULA) in
accordance with [RFC4193] with the following algorithm:
o Prefix FC01::/8
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o Global ID: a hash of the domain ID; this way all devices in the
same domain have the same /48 prefix. Conversely, global ID from
different domains are unlikely to clash, such that two networks
can be merged, as long as the policy allows that merge. See also
Section 6 for a discussion on merging domains.
o Subnet ID and interface ID: These can be either derived
deterministically from the name of the device, or assigned at
registration time of the device.
Links inside the ACP only use link-local IPv6 addressing, such that
each node only requires one routable loopback address.
5.8. Routing in the ACP
Once ULA address are set up all autonomic entities should run a
routing protocol within the autonomic control plane context. This
routing protocol distributes the ULA created in the previous section
for reachability. The use of the autonomic control plane specific
context eliminates the probable clash with the global routing table
and also secures the ACP from interference from the configuration
mismatch or incorrect routing updates.
The establishment of the routing plane and its parameters are
automatic and strictly within the confines of the autonomic control
plane. Therefore, no manual configuration is required.
All routing updates are automatically secured in transit as the
channels of the autonomic control plane are by default secured.
The routing protocol inside the ACP should be light weight and highly
scalable to ensure that the ACP does not become a limiting factor in
network scalability. We suggest the use of RPL as one such protocol
which is light weight and scales well for the control plane traffic.
5.9. Connecting a Controller / NMS system
The Autonomic Control Plane can be used by management systems, such
as controllers or network management system (NMS) hosts (henceforth
called simply "NMS hosts"), to connect to devices through it. For
this, an NMS host must have access to the ACP. By default, the ACP
is a self-protecting overlay network, which only allows access to
trusted systems. Therefore, a traditional NMS system does not have
access to the ACP by default, just like any other external device.
The preferred way for an NMS host to connect to the ACP of a network
is to enrol that NMS host as a domain device, such that it shares a
domain certificate with the same trust anchor as the network devices.
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Then, the NMS host can automatically discover an adjacent network
element, and join the ACP automatically, just like a network device
would connect to a neighboring device. Alternatively, if there is no
directly connected autonomic network element, a secure connection to
a single remote network element can be established by configuration,
authenticated using the domain certificates. There, the NMS host
"enters" the ACP, from which point it can use the ACP to reach
further nodes.
If the NMS host does not support autonomic negotiation of the ACP,
then it can be brought into the ACP by configuration. On an adjacent
autonomic node with ACP, the interface with the NMS host can be
configured to be part of the ACP. In this case, the NMS host is with
this interface entirely and exclusively inside the ACP. It would
likely require a second interface for connections between the NMS
host and administrators, or Internet based services. This mode of
connecting an NMS host has security consequences: All systems and
processes connected to this implicitly trusted interface have access
to all autonomic nodes on the entire ACP, without further
authentication. Thus, this connection must be physically controlled.
In both options, the NMS host must be routed in the ACP. This
involves two parts: 1) the NMS host must point default to the AN
device for all IPv6, or for the ULA prefix used inside the ACP, and
2) the prefix used between AN node and NMS host must be announced
into the ACP, and distributed there.
The document "Autonomic Network Stable Connectivity"
[I-D.eckert-anima-stable-connectivity] explains in more detail how
the ACP can be integrated in a mixed NOC environment.
6. Self-Healing Properties
The ACP is self-healing:
o New neighbors will automatically join the ACP after successful
validation and will become reachable using their unique ULA
address across the ACP.
o When any changes happen in the topology, the routing protocol used
in the ACP will automatically adapt to the changes and will
continue to provide reachability to all devices.
o If an existing device gets revoked, it will automatically be
denied access to the ACP as its domain certificate will be
validated against a Certificate Revocation List during
authentication. Since the revocation check is only done at the
establishment of a new security association, existing ones are not
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automatically torn down. If an immediate disconnect is required,
existing sessions to a freshly revoked device can be re-set.
The ACP can also sustain network partitions and mergers. Practically
all ACP operations are link local, where a network partition has no
impact. Devices authenticate each other using the domain
certificates to establish the ACP locally. Addressing inside the ACP
remains unchanged, and the routing protocol inside both parts of the
ACP will lead to two working (although partitioned) ACPs.
There are few central dependencies: A certificate revocation list
(CRL) may not be available during a network partition; a suitable
policy to not immediately disconnect neighbors when no CRL is
available can address this issue. Also, a registrar or Certificate
Authority might not be available during a partition. This may delay
renewal of certificates that are to expire in the future, and it may
prevent the enrolment of new devices during the partition.
After a network partition, a re-merge will just establish the
previous status, certificates can be renewed, the CRL is available,
and new devices can be enrolled everywhere. Since all devices use
the same trust anchor, a re-merge will be smooth.
Merging two networks with different trust anchors requires the trust
anchors to mutually trust each other (for example, by cross-signing).
As long as the domain names are different, the addressing will not
overlap (see Section 5.7).
7. Self-Protection Properties
As explained in Section 5, the ACP is based on channels being built
between devices which have been previously authenticated based on
their domain certificates. The channels themselves are protected
using standard encryption technologies like DTLS or IPsec which
provide additional authentication during channel establishment, data
integrity and data confidentiality protection of data inside the ACP
and in addition, provide replay protection.
An attacker will therefore not be able to join the ACP unless having
a valid domain certificate, also packet injection and sniffing
traffic will not be possible due to the security provided by the
encryption protocol.
The remaining attack vector would be to attack the underlying AN
protocols themselves, either via directed attacks or by denial-of-
service attacks. However, as the ACP is built using link-local IPv6
address, remote attacks are impossible. The ULA addresses are only
reachable inside the ACP context, therefore unreachable from the data
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plane. Also, the ACP protocols should be implemented to be attack
resistant and not consume unnecessary resources even while under
attack.
8. The Administrator View
An ACP is self-forming, self-managing and self-protecting, therefore
has minimal dependencies on the administrator of the network.
Specifically, it cannot be configured, there is therefore no scope
for configuration errors on the ACP itself. The administrator may
have the option to enable or disable the entire approach, but
detailed configuration is not possible. This means that the ACP must
not be reflected in the running configuration of devices, except a
possible on/off switch.
While configuration is not possible, an administrator must have full
visibility of the ACP and all its parameters, to be able to do
trouble-shooting. Therefore, an ACP must support all show and debug
options, as for any other network function. Specifically, a network
management system or controller must be able to discover the ACP, and
monitor its health. This visibility of ACP operations must clearly
be separated from visibility of data plane so automated systems will
never have to deal with ACP aspect unless they explicitly desire to
do so.
Since an ACP is self-protecting, a device not supporting the ACP, or
without a valid domain certificate cannot connect to it. This means
that by default a traditional controller or network management system
cannot connect to an ACP. See Section 5.9 for more details on how to
connect an NMS host into the ACP.
9. Security Considerations
An ACP is self-protecting and there is no need to apply configuration
to make it secure. Its security therefore does not depend on
configuration.
However, the security of the ACP depends on a number of other
factors:
o The usage of domain certificates depends on a valid supporting PKI
infrastructure. If the chain of trust of this PKI infrastructure
is compromised, the security of the ACP is also compromised. This
is typically under the control of the network administrator.
o Security can be compromised by implementation errors (bugs), as in
all products.
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Fundamentally, security depends on correct operation, implementation
and architecture. Autonomic approaches such as the ACP largely
eliminate the dependency on correct operation; implementation and
architectural mistakes are still possible, as in all networking
technologies.
10. IANA Considerations
This document requests no action by IANA.
11. Acknowledgements
This work originated from an Autonomic Networking project at Cisco
Systems, which started in early 2010. Many people contributed to
this project and the idea of the Autonomic Control Plane, amongst
which (in alphabetical order): Ignas Bagdonas, Parag Bhide, Alex
Clemm, Toerless Eckert, Yves Hertoghs, Bruno Klauser, Max Pritikin,
Ravi Kumar Vadapalli.
Further input and suggestions were received from: Rene Struik, Brian
Carpenter, Benoit Claise.
12. Change log [RFC Editor: Please remove]
12.1. Initial version
First version of this document:
[I-D.behringer-autonomic-control-plane]
12.2. draft-behringer-anima-autonomic-control-plane-00
Initial version of the anima document; only minor edits.
12.3. draft-behringer-anima-autonomic-control-plane-01
o Clarified that the ACP should be based on, and support only IPv6.
o Clarified in intro that ACP is for both, between devices, as well
as for access from a central entity, such as an NMS.
o Added a section on how to connect an NMS system.
o Clarified the hop-by-hop crypto nature of the ACP.
o Added several references to GDNP as a candidate protocol.
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o Added a discussion on network split and merge. Although, this
should probably go into the certificate management story longer
term.
12.4. draft-behringer-anima-autonomic-control-plane-02
Addresses (numerous) comments from Brian Carpenter. See mailing list
for details. The most important changes are:
Introduced a new section "overview", to ease the understanding of
the approach.
Merged the previous "problem statement" and "use case" sections
into a mostly re-written "use cases" section, since they were
overlapping.
Clarified the relationship with draft-eckert-anima-stable-
connectivity
12.5. draft-behringer-anima-autonomic-control-plane-03
o Took out requirement for IPv6 --> that's in the reference doc.
o Added requirement section.
o Changed focus: more focus on autonomic functions, not only virtual
out of band. This goes a bit throughout the document, starting
with a changed abstract and intro.
12.6. draft-ietf-anima-autonomic-control-plane-00
No changes; re-submitted as WG document.
13. References
[I-D.behringer-anima-reference-model]
Behringer, M., Carpenter, B., Eckert, T., Ciavaglia, L.,
Liu, B., Jeff, J., and J. Strassner, "A Reference Model
for Autonomic Networking", draft-behringer-anima-
reference-model-03 (work in progress), June 2015.
[I-D.behringer-autonomic-control-plane]
Behringer, M., Bjarnason, S., BL, B., and T. Eckert, "An
Autonomic Control Plane", draft-behringer-autonomic-
control-plane-00 (work in progress), June 2014.
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[I-D.carpenter-anima-gdn-protocol]
Carpenter, B. and B. Liu, "A Generic Discovery and
Negotiation Protocol for Autonomic Networking", draft-
carpenter-anima-gdn-protocol-04 (work in progress), June
2015.
[I-D.eckert-anima-stable-connectivity]
Eckert, T. and M. Behringer, "Using Autonomic Control
Plane for Stable Connectivity of Network OAM", draft-
eckert-anima-stable-connectivity-01 (work in progress),
March 2015.
[I-D.pritikin-anima-bootstrapping-keyinfra]
Pritikin, M., Richardson, M., Behringer, M., and S.
Bjarnason, "Bootstrapping Key Infrastructures", draft-
pritikin-anima-bootstrapping-keyinfra-02 (work in
progress), July 2015.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
DOI 10.17487/RFC4122, July 2005,
<http://www.rfc-editor.org/info/rfc4122>.
[RFC4193] Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
Addresses", RFC 4193, DOI 10.17487/RFC4193, October 2005,
<http://www.rfc-editor.org/info/rfc4193>.
[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>.
[RFC7576] Jiang, S., Carpenter, B., and M. Behringer, "General Gap
Analysis for Autonomic Networking", RFC 7576,
DOI 10.17487/RFC7576, June 2015,
<http://www.rfc-editor.org/info/rfc7576>.
Authors' Addresses
Michael H. Behringer (editor)
Cisco Systems
Building D, 45 Allee des Ormes
Mougins 06250
France
Email: mbehring@cisco.com
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Steinthor Bjarnason
Cisco Systems
Email: sbjarnas@cisco.com
Balaji BL
Cisco Systems
Email: blbalaji@cisco.com
Toerless Eckert
Cisco Systems
Email: eckert@cisco.com
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