Internet DRAFT - draft-boucadair-network-automation-requirements
draft-boucadair-network-automation-requirements
Network Working Group M. Boucadair
Internet-Draft C. Jacquenet
Intended status: Informational France Telecom
Expires: August 17, 2015 L. Contreras
Telefonica I+D
February 13, 2015
Requirements for Automated (Configuration) Management
draft-boucadair-network-automation-requirements-05
Abstract
Given the ever-increasing complexity of the configuration tasks
required for the dynamic provisioning of IP networks and services,
this document aims at listing the requirements for an automated
configuration management framework.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Scope & Overall Context . . . . . . . . . . . . . . . . . . . 4
4. Motivations . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. Issues Raised by Configuration Operations . . . . . . . . . . 5
5.1. Heterogeneous Environments . . . . . . . . . . . . . . . 5
5.2. Complex Topologies . . . . . . . . . . . . . . . . . . . 6
5.3. Multi-Functional Devices . . . . . . . . . . . . . . . . 6
5.4. Performance Impacts . . . . . . . . . . . . . . . . . . . 6
5.5. Scalability . . . . . . . . . . . . . . . . . . . . . . . 7
5.6. Limits of Manual Configuration . . . . . . . . . . . . . 7
5.7. Security Issues . . . . . . . . . . . . . . . . . . . . . 8
6. Introducing Service-Driven Configuration Management . . . . . 8
7. Detailed Requirements . . . . . . . . . . . . . . . . . . . . 9
7.1. Protocol Requirements . . . . . . . . . . . . . . . . . . 9
7.1.1. Functional Requirements . . . . . . . . . . . . . . . 9
7.1.2. Performance Requirements . . . . . . . . . . . . . . 10
7.1.3. Backward Compatibility . . . . . . . . . . . . . . . 10
7.2. Requirements for Configuration Information . . . . . . . 11
7.2.1. Network Services . . . . . . . . . . . . . . . . . . 12
7.2.2. Forwarding Services . . . . . . . . . . . . . . . . . 13
7.3. Global Management Requirements . . . . . . . . . . . . . 14
7.3.1. Fault Management . . . . . . . . . . . . . . . . . . 14
7.3.2. Configuration Management . . . . . . . . . . . . . . 14
7.3.3. Performance Management . . . . . . . . . . . . . . . 15
7.4. Security Management . . . . . . . . . . . . . . . . . . . 15
7.4.1. Device Authentication . . . . . . . . . . . . . . . . 15
7.4.2. Integrity of Configuration Information . . . . . . . 16
7.4.3. Confidentiality of Exchanged Data . . . . . . . . . . 16
7.4.4. Key Management . . . . . . . . . . . . . . . . . . . 16
7.4.5. Connection Log . . . . . . . . . . . . . . . . . . . 16
7.4.6. Profiles . . . . . . . . . . . . . . . . . . . . . . 16
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
9. Security Considerations . . . . . . . . . . . . . . . . . . . 16
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17
11. Informative References . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
IP network and service configuration procedures are currently handled
by skilled personnel who is often required to acquire a high level of
expertise that grows as the variety and the complexity of the
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services to be delivered over an IP network. This demand for a high
level of expertise is further increased by heterogeneous network and
service environments where each equipment manufacturer has developed
its own proprietary interfaces and configuration schemes. As a
consequence, the time to deliver complex yet advanced IP service
offerings (such as IP TV, VPN, etc.) is also increasing at the risk
of jeopardizing customers' quality of experience.
This document advocates for the need to undertake a standardization
effort to define an automated provisioning framework that includes a
set of interfaces and protocol(s) for conveying configuration
information which should help in facilitating the automation of the
network resource allocation and service delivery procedures.
Defining standard data and information models [RFC3444] to capture
offered network services would help to automate the process of
service ordering and activation and therefore accelerating service
provisioning.
Automation should not be targeted at dynamically enforcing policies
only, but also be encouraged to:
o Generate policy-related and configuration data based on a well-
defined set of triggers and events.
o Monitor the outcome of a configured function/device to assess
whether the observed behavior is aligned with the expected
behavior.
This document assumes that service differentiation at the network
layer can be enforced by tweaking various parameters which belong to
distinct dimensions (e.g, forwarding, routing, traffic access
management, traffic classification, etc.). As such, the decision
point is likely to interact with several engines (e.g., routing
engine, forwarding engine, etc.). In particular, this document
considers that an I2RS system can be seen as a subset of an overall
framework. I2RS is limited to routing and forwarding actions (see
Section 7.2.2). To meet performance requirements (see
Section 7.1.2), it is encouraged to design a system which interacts
directly with the routing and forwarding system, rather than
requiring local proxy functions which are responsible for translating
vendor-independent commands and policies into vendor-specific
configuration commands and syntax.
In addition to protocol-related considerations, automating network
operations heavily relies upon the availability of intelligent policy
decision points. Sharing best design practices for policy decision
point logics would facilitate the adoption of the proposed approach
(see Section 6).
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The document enumerates a set of encountered issues (see Section 5)
and identifies a set of requirements (see Section 7). A service-
driven approach is purposed in Section 6.
2. Terminology
This document makes use of the following terms:
o Decision point: is an entity that is responsible for making
decisions that yield the production of configuration information
which will be conveyed towards (and processed by) the set of
relevant managed entities.
o Managed entity: any (networking) device that will participate in
the establishment, the activation and the maintenance of a given
service. Such devices MAY include routers and terminals, whatever
the configuration procedures and underlying technologies to be
used for the delivery of the said service.
3. Scope & Overall Context
Maintain and operate self-adaptive networks may be seen as a long
term objective for IP service providers. To achieve this goal,
intermediate objectives should be defined, such as:
1. Define a framework to expose IP connectivity services to external
parties, including peering IP network operators, content
providers, services relying on connectivity services (e.g., IP
TV, VoIP) (see for example [RFC7297]).
2. Ability to automatically translate IP connectivity requirements
into configuration and provision actions.
3. Dynamically adapt service configuration to be aligned with
expected service objectives.
4. Automate service negotiation and service activation (e.g.,
[I-D.boucadair-connectivity-provisioning-protocol]).
5. Optimize resource utilization, e.g., automatically set traffic
engineering objectives.
Discussing the items above is out of scope. This document only
discusses requirements for (automated) configuration procedures and
protocol.
4. Motivations
Service providers and network operators have gained experience in
implementing, deploying and manipulating a large set of protocols and
associated information. Some data models have also been defined for
network management purposes. Thus, several protocols have been
standardized, such as SNMP (Simple Network Management Protocol
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[RFC3410]), COPS (Common Open Policy Service [RFC2748]), (COPS-PR
[RFC3084]) or, more recently, NETCONF [RFC6241].
In addition, multiple data models have been defined and used by
operators like CIM (Core Information Model), DEN (Directory-Enabled
Network), SMI (Structure of Management Information [RFC2578]), SPPI
(Structure of Policy Provisioning Information [RFC3159]), and, more
recently, YANG [RFC6022].
Despite this standardization effort, most of the service operators
still assume manual configuration through proprietary CLI (Command
Line Interface) commands possibly combined with in-house developed,
vendor-specific scripts to proceed with the configuration of numerous
features, such as forwarding and routing capabilities, Quality of
Service (sometimes including traffic engineering) capabilities, and
security capabilities. Some of these requirements are fulfilled by
existing tools/protocols but there is still a lack of wide adoption
of those tools.
Other non-technological challenges are also to be taken into
consideration when discussing network automation (e.g., to what
extent an automated system will accommodate both simple and complex
business scenarios, how an automated system will evolve to
accommodate changes and new procedures, assess the impact on testing
methodologies,etc.).
The purpose of this document is to document requirements rather than
focusing on the non-technological challenges.
5. Issues Raised by Configuration Operations
The following sub-sections enumerates a set of issues.
5.1. Heterogeneous Environments
The delivery of IP services relies upon the activation of a set of
capabilities located in various devices that include routers,
switches, service platforms, etc. In particular, a large set of
protocols need to be configured, such as routing protocols,
management protocols, security protocols, let alone capabilities that
relate to addressing scheme management, policy enforcement, etc.
Such a diversity of features and protocols may increase the risk of
inconsistency at the cost of QoS degradation or even service
disruption. Therefore, the configuration information which is
forwarded to the whole set of participating devices for delivering a
given service or a set of services should be consistent, whatever the
number of features/services to be activated/deployed in the network.
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5.2. Complex Topologies
Network operators should have means to dynamically discover the
topology of the network.
Such topological information should be as elaborate as possible,
including details like the links that connect network devices, their
capacity, such as the total bandwidth, the available bandwidth, the
bandwidth that can be reserved, etc.
5.3. Multi-Functional Devices
Numerous, often multi-vendor devices are involved in the delivery of
IP services. These devices support various capabilities that need to
be combined for the delivery of a given service or a set of services.
The availability and status of such capabilities is therefore a
critical information for service providers, since it is likely to
affect service and network design, let alone operational procedures.
Therefore, service providers and network operators should have means
to:
o Dynamically retrieve, list and classify the capabilities supported
by a given device (or a set thereof),
o Dynamically acquire detailed information about the availability
and status of any activated capability of any device at any given
time.
o Dynamically retrieve the version of embedded software modules,
interfaces, OS version, etc.
5.4. Performance Impacts
Configuring a set of devices to deliver a service takes time. In
addition, depending on the complexity of the service, erroneous
configurations may occur at the cost of jeopardizing the overall
quality of a service, if not causing service disruption. From this
perspective, some performance indicators must be defined and measured
to assess:
o The time to deliver a service, from subscription to operation.
Such indicator may be further decomposed into elementary
performance metrics, e.g., the time it takes to complete the
configurations tasks that are specific to the enforcement of a
given policy (forwarding, routing, QoS, etc.)
o The impact of any configuration change on the overall service
performance (including customer's own perception).
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Tools to qualify (by simulation or emulation) any possible impact of
an elementary configuration task before such task is performed should
be supported. These tools aims to prevent errors amplification.
5.5. Scalability
As far as scalability is concerned, adequate indicators should be
specified in order to assess the ability of configuration techniques
and protocols to support a large number of simultaneous processes.
The maintenance of these processes should not impact the performance
of the configuration system as a whole (i.e., manager and managed
entities, amount of configuration task-specific traffic exchanged
between manager and managed entities, periodicity of configuration
operations, etc.).
Therefore, configuration operations should be qualified with
performance indicators in order to check whether the architecture
designed for configuration management is scalable in terms of:
o Amount of configuration data to be processed per unit of time, as
a function of the number and the nature of the capabilities and
devices that need to be configured.
o Amount of traffic generated by any reporting mechanism that may be
associated to a configuration process.
o Number of processes that are created in order to achieve specific
configuration operations.
5.6. Limits of Manual Configuration
Manual configuration is not only a likely source of errors, but it
also affects the time it takes to complete a configuration task (or a
combination thereof) to deliver a service, as a function of the task
complexity and the need for global consistency. Thus, the efficiency
of a configuration process is likely to be improved by the
introduction of a high level of automation. Automation is defined as
follows:
o Automatic provisioning of configuration information to the
participating devices.
o Dynamic enforcement of policies (possibly based upon the use of
dynamic resource allocation techniques).
o Dynamic reporting mechanisms to notify about the actual processing
of configuration information by a participating device.
o Autonomic provisioning capabilities for triggering self-
configuration mechanisms for the network devices.
Refer to Section 4.1 of [RFC7149] for a discussion on the
implications of full automation.
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5.7. Security Issues
Configuring a network or a service raises several security issues,
including (but not limited to):
o The integrity of the configuration information, possibly yielding
the preservation of the confidentiality of such information when
being forwarded over a public IP infrastructure,
o The need for authorizing and authenticating devices/entities that
have the ability of manipulating configuration information
(define, instantiate, forward and process),
o Mutual authentication between manager and managed entities.
6. Introducing Service-Driven Configuration Management
Current practice consists in configuring elementary functions, i.e.,
configuration management for a given service offering is decomposed
into a set of elementary tasks. Thus, the consistency of
configuration operations for the sake of service delivery must be
checked by any means appropriate.
A network device should be seen as a means to deploy a service and
not just as a component of such service. Thus, service delivery
procedures should not assume the configuration of devices one after
the other, but rather globally, i.e., at the scale of the network
that supports the said service. Such a service-driven configuration
management scheme is therefore meant to facilitate and improve the
completion of configuration tasks, by means of highly automated,
service-wise, global configuration procedures.
This in particular assumes the need for robust configuration
mechanisms that include appropriate protocol machinery (e.g., from a
reliable transport mode perspective) to convey configuration
information between manager and managed entities, as well as reliable
consistency check procedures. The latter is not only meant to assess
the validity of all the configuration operations service-wise, but
also the efficiency of the corresponding yet dynamic policy
enforcement and resource allocation schemes.
An implementation example is the case of service providers who could
dedicate (logical) centralized entities which are responsible for the
provisioning and the management of participating devices. The main
function of these centralized entities is to make appropriate
decisions and generate the decision-derived configuration data that
will be forwarded to the participating devices. In addition, these
centralized entities will make sure of the consistency of the
decisions that have been made to deliver the service, according to a
dynamic configuration policy enforcement scheme. These logical
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entities will be responsible for assessing whether the enforced
policies are compliant with the expected behavior and how efficiently
they are enforced.
Service-driven configuration management leads to the following
assumptions:
o Data and information models must be service-oriented,
o Configuration protocol(s) should reuse existing standard data and
information models as much as possible,
o Configuration protocol(s) should be flexible enough to facilitate
the support of new features without compromising the protocol
robustness (especially from a performance and scalability
standpoints),
o Configuration protocol(s) should provide means to check the
consistency of configuration information service-wise.
7. Detailed Requirements
7.1. Protocol Requirements
Configuration information must be provided to the participating
devices by means of a protocol to be used between such devices and a
presumably centralized manager entity. The latter can be seen as a
decision point where configuration information is stored, maintained
and updated whenever required.
Decisions about configuring additional features or devices, enforcing
policies and allocating resources are made accordingly, e.g., as a
function of the number of Service Level Specification templates that
are processed per unit of time combined with traffic forecasts that
are updated on a regular basis. Such decisions are converted into
configuration information that is forwarded towards the relevant
managed entities.
7.1.1. Functional Requirements
The vendor-independent communication protocol for conveying
configuration information should have the following characteristics:
1. The protocol must be reliable, and be independent from the
network layer (i.e., configuration information must be conveyed
over IPv4 and IPv6 network infrastructures indifferently),
2. The protocol architecture should provide a means for dynamically
providing the configuration information to the participating
devices, so that a high level of automation is introduced in the
actual delivery of any given service.
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3. The protocol should provide the relevant means (encoding
capabilities, operation and command primitives, extension
capabilities that allow additional operations, etc.) to be able
to reliably and securely convey configuration information,
4. The protocol should be a privileged vector for the dynamic
provisioning of configuration data, as well as the dynamic
enforcement of any policy such as a routing policy, a QoS policy
or a security policy. This requirement suggests the definition
and the support of vendor-independent instantiation procedures
that will aim at uniquely identifying the configuration data
model and the policy enforcement scheme that refer to a given IP
service.
5. The protocol should support a reporting mechanism for various
purposes, including the assessment of the efficiency of a given
policy, the ability to dynamically notify the aforementioned
decision point about the completion of a set of configuration
tasks, or the ability to dynamically report any event that may
affect global service operation,
6. The protocol should support the appropriate security mechanisms
to provide guarantees as far as the preservation of the
confidentiality of the configuration information is concerned.
7. The protocol should provide a mean of preserving the order in
which the configuration information should be applied in the
participating devices. The ordering of the configuration
information could be implemented by means of sequence numbers,
timing or scheduling indicators, etc. Through this requirement,
any aged or disordered configuration information is prevented to
be applied to the devices.
7.1.2. Performance Requirements
The protocol for conveying configuration information within a network
should be designed so that:
1. The activation of the protocol by the participating devices must
not affect the overall performance of such devices, whatever the
amount of configuration data these devices will have to process
at any given time.
2. The activation of the protocol should not dramatically affect the
global resources of the network infrastructure that will convey
configuration information whatever its amount and scope (e.g.,
the set of policies that need to be dynamically enforced).
7.1.3. Backward Compatibility
The introduction and the activation of a protocol for conveying
configuration information should allow for smooth migration
procedures, so that vendor-specific and vendor-independent
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configuration procedures may gracefully co-exist on a (hopefully)
limited period of time.
Also, in case of any kind of protocol failure, it must be possible to
rely upon any vendor-specific configuration procedure as some kind of
rollback procedure. Such a rollback procedure must protect services
that are up and running from any risk of disruption.
7.2. Requirements for Configuration Information
Configuration tasks are currently performed with vendor-specific
solutions that reflect technology-specific information. It is
therefore more and more difficult for a service provider to get a
unified, homogeneous view of the network resources service-wise
(rather than device-wise).
Configuration information should therefore be provided to the
participating devices as unified, vendor-agnostic, service
configuration parameters. These parameters must reflect a
standardized service data model rather than a vendor-specific
information model, unlike the current situation. Examples of such
service data models include a tunneling service, an intra-domain
routing service, or a VPN service.
The need for a unified, homogeneous access to a multi-vendor
environment is becoming critical for N-Play, residential and
corporate, fixed and mobile service providers so that a high level of
automation can be introduced while proceeding with the configuration
of the said multi-vendor environment. This unification is clearly
conditioned by the availability of two key components: A
configuration protocol (the container) and a set of data models (the
content).
The standardization of these two components has several yet major
benefits:
o Devices are seen as functional blocks that support a set of
standardized capabilities;
o These functional blocks are described as vendor-independent
capabilities;
o These functional blocks are all managed homogeneously, whatever
the underlying technology.
As a consequence, it becomes possible to add semantic rules to
automate detection and correction of erroneous configurations, either
at the scale of a single device or at the scale of a whole network.
Furthermore, an equipment from vendor X could de replaced by another
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technology from vendor Y with very little impact (if no impact at
all) on the configuration management procedures.
To do so, the data models should satisfy the following requirements.
7.2.1. Network Services
7.2.1.1. Interface Identification
Configuration information for identification purposes mostly deals
with the naming of any interface supported by a given device. This
naming scheme describes the properties of an interface, and must take
into account all the parameters that are required to correctly
configure an interface. The following information must be provided:
o A name, with a generic syntax that is vendor-agnostic by nature.
The name can define the media type of the interface. Depending on
the medium type, further information MAY be added (such as MTU,
bandwidth, supported framing and encapsulation modes, etc.).
o The interface technology (e.g., optical / electrical) and nominal
capacity (e.g., 10 GE / 100 GE).
o Optionally, a logical descriptor (e.g., VLANs declared on Ethernet
interfaces). In this case the encapsulation mode must be part of
the configuration information.
o Optionally, a description field that provides general (possibly
administrative) information about the interface.
7.2.1.2. Quality of Service (QoS)
IP services are provided with a level of quality that MAY be
guaranteed (either qualitatively or quantitatively) by any means
appropriate. QoS policies should be dynamically enforced according
to a data model that will accurately reflect all the elementary QoS
capabilities that MAY be configured and activated to enforce such
policies.
For instance, in the case of the activation of the Diffserv QoS model
within a network infrastructure, the participating routers should be
provided with the appropriate PHB (Per Hop Behavior) configuration
parameters.
Additional information relevant to the service, such as path
protection, can be provided to the participating devices to mitigate
network failures. This information can be proactively or reactively
provided, according to the service level agreed.
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7.2.1.3. Applications
Network devices usually support functions that allow the activation
of specific services like HTTP, BOOTP, DHCP, SYSLOG, etc. These
devices must therefore be provided with the corresponding
configuration information.
7.2.2. Forwarding Services
7.2.2.1. Routing and Forwarding Configuration Information
Routing and forwarding configuration information deals with the
decision that should be applied by a participating device to forward
an incoming IP datagram, according to the (possibly service-specific)
forwarding and routing policies defined by the service provider.
From this perspective, the participating devices should be provided
with the following configuration information:
1. Metric information for IGP route computation purposes,
2. Attribute information for BGP route computation purposes,
3. Static routes (if any).
Any candidate protocol must be compliant with the following
requirements:
1. Ability to retrieve routing and forwarding tables.
2. Ability to retrieve the configuration information of each
routing/forwarding device.
3. Ability to retrieve the capabilities of each routing/forwarding
device.
4. Ability to dynamically enforce policies on active routing
processes.
5. Ability to dynamically inject new routing and forwarding entries.
6. Ability to receive notifications when route changes occurred,
tagged by the decision point.
7.2.2.2. Traffic Engineering Configuration Information
Traffic Engineering (TE) is an important and often complex task of
configuration management: the participating devices should be
provided with the configuration information that will help them to
select the appropriate routes that lead to a set of destinations,
according to specific constraints and requirements that may have been
dynamically negotiated with the customer.
These constraints may be expressed in terms of time duration (e.g.,
the use of a traffic-engineered route on a weekly basis), traffic
characterization (e.g., all IP multicast traffic should be forwarded
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along a specific distribution tree), security concerns (e.g., use
IPsec tunnels), and/or QoS considerations (e.g., EF (Expedited
Forwarding)-marked traffic [RFC3246] should always use a subset of
"EF-compliant" routes).
7.2.2.3. Configuration Information for Tunnel Design and Activation
7.2.2.3.1. Tunnel Identification Information
The identification of a tunnel should be globally unique, especially
if the tunnel is to be established and activated across autonomous
systems. The tunnel identification schemes (e.g., endpoint
numbering) should be left to service providers, assuming that the
corresponding formalism is commonly understood, whatever the number
of autonomous systems the tunnel may cross.
The tunnel identification information should at least be composed of
the tunnel endpoint identification information. The tunnel
identification information MAY also be composed of an informal
description of the tunnel, e.g., the purpose of its establishment,
customer traffic that may be forwarded into this tunnel, etc.
7.2.2.3.2. Tunneling Protocol Configuration Information
Any participating device must be provided with the configuration
information related to the tunneling technique to be used for the
establishment and the activation of the tunnel. Such techniques
include Generic Routing Encapsulation (GRE, [RFC2784]), IP Secure in
tunnel mode (IPsec, [RFC2401]), Layer 2 Tunneling Protocol (L2TP,
[RFC2661]), etc.
7.3. Global Management Requirements
7.3.1. Fault Management
Mechanisms to monitor and report any fault that affects service
operation should be independent of the configuration protocol.
7.3.2. Configuration Management
Errors during a configuration procedure could impact the availability
of a given service offering, while consistency checks are mandatory
so as to correctly enforce a configuration policy.
The following requirements have been identified:
o Provisioning of configuration information should be as automated
as possible,
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o Mechanisms to detect and diagnose configuration errors must be
supported,
o Consistency of configuration operations service-wise must be
checked,
o Simulation tools should be used to assess the validity of
configuration information before it is downloaded to the relevant
participant devices.
o Autonomic provisioning capabilities should be enabled to
facilitate new device deployments in an automatic way, ideally
without any human configuration intervention. Of course, the
procedure must be designed to allow for administrative validation
under some events. The purpose of allowing for such events is to
ease troubleshooting and react to failures events when unexpected
behaviors are experienced.
o Means to prevent against "mad robot" phenomena should be
supported.
7.3.3. Performance Management
Performance management is key for guaranteeing Service Assurance by
proactively detecting network degradation.
In a vendor-agnostic scenario, the mechanisms for performance
management should implement standardized measurements among the
involved devices, represented by abstract, standard data models.
There are a number of measurements that can be taken into account for
different purposes, such as CPP validation, bandwidth utilization or
network and service level resilience. To that end, the performance
management tools should provide reporting capabilities of the
obtained measurements through counters or any other mean agnostic to
specific vendor implementations.
The activation (and de-activation) of the reporting capabilities MAY
be enabled by using automated configuration mechanisms.
7.4. Security Management
7.4.1. Device Authentication
It must be possible to activate mutual authentication between manager
and managed entities. The authentication must be checked before
exchanging any configuration data, so as to prevent DoS (Denial of
Service) attacks.
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7.4.2. Integrity of Configuration Information
Two types of integrity must be provided. The first one may be done
at the network layer, e.g., by using the IPsec protocol suite. The
second type should protect configuration data at the application
layer (e.g., the entire file configuration is integrity protected).
7.4.3. Confidentiality of Exchanged Data
The participating device should provide security functions that
provide confidentiality. Encryption algorithms must be standard and
manually or automatically activated.
7.4.4. Key Management
The configuration system must provide a scalable key management
scheme. The number of keys to be managed must be at most linearly
proportional to the number of the devices.
7.4.5. Connection Log
The participating device must log all configuration connections. At
least the following information must be provided:
o Identity of the device which provided the configuration
information,
o Date of the connection,
o Identity of the user who has initiated the configuration process,
o Description of the configuration information that has been
forwarded.
7.4.6. Profiles
The configuration system must allow the definition and the activation
of several privilege levels. Each level could be associated to a set
of administrative functions. Each configuration administrator could
be assigned a specific access level to perform a (possibly limited)
set of configuration tasks.
8. IANA Considerations
This document does not require any action from IANA.
9. Security Considerations
This document reflects a set of requirements as far as the design and
the enforcement of configuration policies are concerned for
(automated) service subscription, delivery and maintenance. The
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document addresses some security concerns that have been depicted in
Section 7.4, and that should be taken into account when considering
the specification of a protocol that will convey configuration
information, as well as configuration information itself.
10. Acknowledgements
Many thanks to M. Achemlal and Y. Adam who contributed to a first
version of this text.
Thanks for W. George for the comments.
11. Informative References
[I-D.boucadair-connectivity-provisioning-protocol]
Boucadair, M., Jacquenet, C., Zhang, D., and P.
Georgatsos, "Connectivity Provisioning Negotiation
Protocol (CPNP)", draft-boucadair-connectivity-
provisioning-protocol-08 (work in progress), September
2014.
[RFC2401] Kent, S. and R. Atkinson, "Security Architecture for the
Internet Protocol", RFC 2401, November 1998.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2661] Townsley, W., Valencia, A., Rubens, A., Pall, G., Zorn,
G., and B. Palter, "Layer Two Tunneling Protocol "L2TP"",
RFC 2661, August 1999.
[RFC2748] Durham, D., Boyle, J., Cohen, R., Herzog, S., Rajan, R.,
and A. Sastry, "The COPS (Common Open Policy Service)
Protocol", RFC 2748, January 2000.
[RFC2784] Farinacci, D., Li, T., Hanks, S., Meyer, D., and P.
Traina, "Generic Routing Encapsulation (GRE)", RFC 2784,
March 2000.
[RFC3084] Chan, K., Seligson, J., Durham, D., Gai, S., McCloghrie,
K., Herzog, S., Reichmeyer, F., Yavatkar, R., and A.
Smith, "COPS Usage for Policy Provisioning (COPS-PR)", RFC
3084, March 2001.
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[RFC3159] McCloghrie, K., Fine, M., Seligson, J., Chan, K., Hahn,
S., Sahita, R., Smith, A., and F. Reichmeyer, "Structure
of Policy Provisioning Information (SPPI)", RFC 3159,
August 2001.
[RFC3246] Davie, B., Charny, A., Bennet, J., Benson, K., Le Boudec,
J., Courtney, W., Davari, S., Firoiu, V., and D.
Stiliadis, "An Expedited Forwarding PHB (Per-Hop
Behavior)", RFC 3246, March 2002.
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction and Applicability Statements for Internet-
Standard Management Framework", RFC 3410, December 2002.
[RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between
Information Models and Data Models", RFC 3444, January
2003.
[RFC6022] Scott, M. and M. Bjorklund, "YANG Module for NETCONF
Monitoring", RFC 6022, October 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)", RFC
6241, June 2011.
[RFC7149] Boucadair, M. and C. Jacquenet, "Software-Defined
Networking: A Perspective from within a Service Provider
Environment", RFC 7149, March 2014.
[RFC7297] Boucadair, M., Jacquenet, C., and N. Wang, "IP
Connectivity Provisioning Profile (CPP)", RFC 7297, July
2014.
Authors' Addresses
Mohamed Boucadair
France Telecom
Rennes 35000
France
Email: mohamed.boucadair@orange.com
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Christian Jacquenet
France Telecom
Rennes 35000
France
Email: christian.jacquenet@orange.com
Luis M. Contreras
Telefonica I+D
Ronda de la Comunicacion, s/n
Madrid 28050
Spain
Email: lmcm@tid.es
URI: http://people.tid.es/LuisM.Contreras/
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