Internet Engineering Task Force T. Tsou
Internet-Draft Huawei Technologies
Intended status: Informational J. Schoenwaelder, Ed.
Expires: August 12, 2011 Jacobs University Bremen
Y. Shi
Hangzhou H3C Tech. Co., Ltd.
T. Taylor, Ed.
Huawei Technologies
February 8, 2011
Problem Statement for the Automated Configuration of Large IP Networks
draft-ietf-opsawg-automated-network-configuration-00
Abstract
This memo discusses the steps required to bring network devices in a
service provider network into service in an automated fashion. The
memo identifies known solutions where they exist, but notes some gaps
that require further specification.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
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This Internet-Draft will expire on August 12, 2011.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. A Model of the Process . . . . . . . . . . . . . . . . . . . . 5
4. Pre-configuration . . . . . . . . . . . . . . . . . . . . . . 6
5. Bootstrapping . . . . . . . . . . . . . . . . . . . . . . . . 6
5.1. Establishment of Link Layer Connectivity . . . . . . . . . 7
5.2. Acquisition of IP Addresses and Basic Routing
Information . . . . . . . . . . . . . . . . . . . . . . . 7
5.3. Finding the Configuration Server . . . . . . . . . . . . . 7
5.4. Establishing a Secure Channel to the Configuration
Server . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6. Initial Configuration and Configuration Updates . . . . . . . 10
7. Configuration Auditing . . . . . . . . . . . . . . . . . . . . 13
8. Missing Specifications . . . . . . . . . . . . . . . . . . . . 13
9. Security Considerations . . . . . . . . . . . . . . . . . . . 14
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 15
12. Informative References . . . . . . . . . . . . . . . . . . . . 15
Appendix A. Open Issues . . . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
New service provider networks are being deployed that entail the
installation of tens of thousands of new network devices. To keep
costs down, it is desirable to automate the establishment of such
networks and the configuration of these network devices to the
maximum extent possible. A certain amount of the information needed
to operate them must be pre-configured by the vendor or service
provider before the devices are physically deployed. Other
information is best delivered after startup, to ensure that it is
consistent with the physical deployment.
3GPP work in progress describes requirements [TS_32_500] and an
architectural specification [TS_36_300] for the self-configuration of
edge node entities called eNodeBs. (The expansion of eNodeB is too
unwieldy to spell out.) Specifically, procedures are specified for
establishing transport connections to and for exchanging
configuration data with control entities called MMEs (Mobility
Management Entities) and with neighbouring eNodeBs. [TS_36_300]
currently assumes as a starting precondition that the eNodeB knows
its own IP address and knows IP address endpoints for the target MMEs
and neighbouring eNodeBs.
The Broadband Forum has defined a CPE WAN Management Protocol
(running over SOAP/HTTP/TLS) to manage customer premise equipment
(CPE) terminating broadband access networks (typically DSL access
networks) [TR_069]. CPE devices locate and connect to an Auto-
Configuration Server (ACS), which provides configuration data and
software/firmware images and modules. The ACS also performs status
and performance monitoring and diagnostic functions. CPE devices use
DHCP to locate an ACS and since both peers, the ACS and CPE, can
initiate connections, the protocol can work across network address
translators (NATs).
IETF work on automated configuration goes back to BOOTP [RFC0951],
followed eight years later by DHCP [RFC1531] and successors. The
years since have seen a steady growth in the number of DHCP options.
The Simple Network Management Protocol (SNMP) [RFC3410] was designed
to convey management information between SNMP entities such as
managers and agents. The number of SNMP MIB modules grew steadily,
but SNMP has not historically seen only limited use for configuration
[RFC3535]. For a period, IETF configuration efforts were focussed on
the distribution of policy in the network. [RFC3139] provides a good
insight into this period. More recently, NETCONF [RFC4741] was
devised as an alternative to SNMP, but the development of standard
NETCONF data models is just beginning.
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Recent IETF work closest in spirit to the 3GPP self-organizing
network effort cited above is embodied in CAPWAP [RFC5415]. Like the
3GPP work, CAPWAP focusses on the configuration of edge nodes, in a
Wi-Fi rather than cellular network. The CAPWAP work goes beyond that
of 3GPP by specifying the process of AC (Access Controller) discovery
rather than leaving discovery out of scope. With regard to the
configuration process itself, CAPWAP provides for the download of new
images to the WTP (Wireless Termination Point). In contrast,
[TS_32_500] assumes that this has already been completed for the
eNodeB.
2. Scenarios
There are two different scenarios to consider. In the first
scenario, called the Intra-domain Scenario, the new network device N
is attached to the network operated by the service provider which is
also operating the new device. In the second scenario, called the
Inter-domain Scenario, the new device N is attached to a third party
network providing connectivity to the network of the service provider
operating the new device.
+------+
| CONF |
+--+---+
+---+ +---+ |
| N +-...-+ R +------+---+---+----...
+---+ +---+ | |
+--+--+ +--+---+
| DNS | | DHCP |
+-----+ +------+
|-- N's Service Provider --|
Figure 1: Intra-domain Scenario
Figure 1 depicts the Intra-domain Scenario. We assume that the new
decive N attaches to a link connected to router R. Furthermore, we
assume that the service provider provides a Domain Name System (DNS)
server, a DHCP server, and a Configuration Server (CONF). Overall,
this scenario does not differ much from conventional network
scenarios.
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+------+
| CONF |
+--+---+
+---+ +---+ +---+ |
| N +-...-+ R +-----+---+---+-----...-+ R +-----+---+---+-----...
+---+ +---+ | | +---+ | |
+--+--+ +--+---+ +--+--+ +--+---+
| DNS | | DHCP | | DNS | | DHCP |
+-----+ +------+ +-----+ +------+
|-- Service Provider X ---| |-- N's Service Provider --|
Figure 2: Inter-domain Scenario
Figure 2 depicts the Inter-domain Scenario where the new device N
attaches to a router R owned by a different service provider X. The
service provider X might offer its own DNS and DHCP services. We
assume that the service provider X has connectivity to the service
provider planning to operate the new device.
In both scenarios, the new device N is either directly reachable or
it may be behind a middlebox such as a NAT or a firewall.
Middleboxes may impose restrictions on which party is able to
initiate communication.
3. A Model of the Process
We introduce a model of the configuration process in order to
identify the parts that have well-known solutions. The remainder may
be worth studying to see if the industry can agree on a solution.
Some basic terminology is needed for the discussion. Depending on
the implementation, let us agree that "configuration data" consist of
software and sets of configured parameters in some combination.
Also, the system that provides the configuration data is called the
"configuration server". Finally, the term "joining device" is used
to denote a network device that is in the process of being
incorporated into the network.
Broadly speaking, the configuration process can be broken into five
phases:
Pre-configuration: configuration carried out either by the vendor or
by the service provider prior to physical installation. One
possible example is the pre-provisioning of certificates, as
described in [RFC5415].
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Bootstrapping: the portion of the process from the time that
physical installation is complete until a secure connection is
established between the joining device and the configuration
server.
Initial configuration: downloading of the configuration data that
the joining device needs to carry out its function in the network.
Auditing of installed configuration: tracking image versions and
configuration parameters for each network device and verifying
that the installed configuration data matches the physical
installation, the network plan, and the records of what data was
downloaded. It is possible that an initial audit of the physical
installation is done before initial configuration, so that the
validity of the intended download can be verified.
Configuration update: transferring configuration data to a fully
configured and operating device from time to time as the need
arises.
4. Pre-configuration
This memo identifies a specific requirement for pre-configuration of
an invariant device identity and authentication-related material in
the form of pre-shared secrets or certificates. There is, as one
alternative, a requirement for pre-configuration of information that
permits the joining device to discover the address of the
configuration server.
5. Bootstrapping
[I-D.sarikaya-core-sbootstrapping] deals with the process of security
bootstrapping, with particular emphasis on the requirements for
highly resource-constrained devices. The document makes a
distinction between a data channel, which is used during network
operation, and a control channel, which is used during bootstrapping.
While both channels can be the same physical channel, they can also
be different (e.g., a wireless access point using an infrared control
channel to receive bootstrapping information). The draft discusses a
number of possible security bootstrapping protocols for resource
constrained devices that can be executed in several bootstrapping
rounds and can be adapted to the specific contexts in terms of the
resources available within individual devices and for the network as
a whole.
For network devices in service provider networks, bootstrapping
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consists of several stages:
1. establishment of link layer connectivity with neighbouring nodes;
2. acquisition of IP addresses and basic routing information;
3. discovery of the configuration server;
4. establishment of a secure channel to the configuration server.
5.1. Establishment of Link Layer Connectivity
The protocol aspects of this phase are out of scope, since it
involves non-IETF protocols only. While some link-layer technologies
may provide authentication and access control, this cannot be assumed
to be available in the general case.
5.2. Acquisition of IP Addresses and Basic Routing Information
For IPv4, DHCPv4 [RFC2131] is widely deployed and the usual way to
obtain an IPv4 address, the IPv4 address of a link-local router and
the IPv4 address of a DNS server. For IPv6, a choice has to be made
between stateful DHCPv6 [RFC3315] versus stateless DHCPv6 [RFC3736]
combined with stateless address autoconfiguration [RFC4862]. In the
latter case, DHCPv6 is needed to configure parameters such as DNS
server addresses. An experimental routing advertisement option to
configure the IPv6 address of a DNS server as part of the stateless
address autoconfiguration is defined in [RFC5006] and may become a
standards-track specification.
Some security protection is provided in this stage by using DHCP
authentication [RFC3118]. However, security of the configuration
process as a whole has to be assured by other means. This is
discussed further below.
Currently the lack of a stable identifier for use in DHCPv6 messaging
is an impediment to authentication of the joining device.
[I-D.ietf-dhc-duid-uuid] discusses the problems with the current
DHCPv6 identifiers (DUIDs) and proposes a new form that could be a
more stable alternative.
5.3. Finding the Configuration Server
Four alternatives are available for finding the configuration server:
o pre-configuration;
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o DHCP configuration;
o Service Location Protocol [RFC2608]; or
o DNS service discovery using SRV records [RFC2782].
Pre-configuration of an IP address is brittle and not recommended.
Pre-configuration of a Uniform Resource Identifier (URI) or fully
qualified domain name (FQDN) is a better approach. One variant that
has been suggested is to burn the URI of a vendor server into the
device's firmware along with a device identifier, and have that
server redirect to the URI of the service provider's configuration
server based on the device identity. Such an approach requires that
a device vendor offers such a service for the lifetime of their
devices and that service providers are able to update the URI of the
service provider's configuration server. This requires a trust
relationship between the vendor and the service provider and
agreement on a protocol to update the redirect information on the
vendor's server.
DHCP configuration can use the usual DHCP options and is technically
straightforward since DHCP is widely used by end user devices to
obtain basic configuration information. There is, however, no
standardized DHCP option to communicate the address of a
configuration server.
The Service Location Protocol (SLP) has seen some usage to locate
services such as printers or file system shares. Usage of SLP to
locate configuration servers requires to define a new service
template [RFC2609].
The use of DNS SRV records requires the joining device to obtain the
correct domain suffix first, presumably from DHCP or via Routing
Advertisements in the case of IPv6 or preconfiguration. A service
type for the desired configuration protocol would have to be defined
in the DNS for the purpose. See Section 3.3 of [RFC5415] for a
discussion of the corresponding discovery process for CAPWAP.
The Inter-domain Scenario requires that the DHCP server or the SLP
server of service provider X's network is able to provide the correct
information to the joining devices. To accomplish this, the
discovery servers need to be able to match a device identification
against a list of possible configuration servers. Furthermore, there
needs to be a mechanism for the service provider operating the
joining device to provision the configuration server's address, e.g.
by using an extension of the Extensible Provisioning Protocol (EPP)
[RFC5730]. However, if the joining device has preconfigured
information about the name of the service provider's network, DNS SRV
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records may be queried after obtaining IP connectivity, avoiding the
need to provision information in service provider X's network.
5.4. Establishing a Secure Channel to the Configuration Server
It is essential that the configuration server and the joining device
authenticate themselves to each other, since the steps leading up to
this point in the process may not be fully secure. This raises two
issues: how the joining device identifies itself, and how
authentication takes place.
It seems best if the device has an invariant identity built in and
accessible to whatever operating system is running on it. If
[I-D.ietf-dhc-duid-uuid], mentioned above, becomes a standard, the
UUID on which that proposal is based would be the required invariant
identity. The vendor should make that identity available in a form
that can be read and transferred into a database accessible to the
configuration server along with the associated configuration data in
advance of the bootstrapping stage (e.g., in bar-coded format on the
device packaging).
This leaves the mutual authentication process itself. This has two
aspects: the security protocol used to perform authentication, and
initial keying methodology. The security protocol is tied together
with the choice of configuration data transport, but the basic
choices are:
o IP Security (IPsec) [RFC4301];
o Transport Layer Security (TLS) [RFC5246];
o Datagram Transport Layer Security (DTLS) [RFC4347];
o Secure Shell (SSH) [RFC4251], [RFC4252], [RFC4253], and [RFC4254];
and
o SNMPv3's User-based Security Model (USM) [RFC3414].
For initial keying methodology, the two basic choices are between
pre-shared secrets and certificates. All of the security protocols
listed above except USM support both methods. USM supports pre-
shared secrets only.
The usual concern with pre-shared secrets is scalability. In the
bootstrapping case, the scale of operation required is linear with
the number of devices to be configured, so it would definitely be a
feasible approach if connection to the configuration system were the
only consideration. The most likely procedure would be for the
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secret to be configured in the device during preconfiguration and
also captured in a database along with the device identity, for use
by the configuration server.
The problem with the use of pre-shared secrets is that the device
needs to authenticate itself at an earlier stage, while it is
establishing communications with its neighbours and acquiring IP
addresses. It seems undesirable to use the same secret for that
purpose as for the connection to the configuration server, on the
basic principle of limiting the potential damage from disclosure of a
particular key.
This need for additional pre-shared secrets argues for consideration
of certificates as an alternative. One issue for certificates is
where the trust anchor resides. It seems logical that it should
reside with the service provider rather than the vendor, to make it
easy to install equipment from multiple vendors. On that basis,
preconfiguration requires service provider input.
CAPWAP (Section 2.4.4.3 of [RFC5415]) makes use of the Extended Key
Usage (EKU) certificate extension [RFC5280] to distinguish
certificates identifying the Access Controllers (i.e., the
configuration servers in the CAPWAP case) from the Wireless Transfer
Points (the configured devices in the CAPWAP case). Thought should
be given to whether such distinctions are required in the general
case of network device configuration.
CAPWAP (Section 12.8 of [RFC5415]) also discusses the use of the
Common Name rather than SubjectAltName field of the certificate to
carry device identity, due to lack of specifications allowing the use
of SubjectAltName to carry MAC addresses. This issue needs to be
investigated further if another form of device unique identity is
used, as discussed above.
Middleboxes such as NATs or firewalls may impose restriction on which
party is able to initiate communication. In the common case of NATs
in IPv4 access networks, communication can only be established from
the device to the configuration server. Not all secure transports,
in particular those where authentication is not symmetric, support
this "call home" mode of operation.
6. Initial Configuration and Configuration Updates
As mentioned at the beginning, the configuration data being
downloaded may be a combination of software and configuration
parameters. Some of the data will be vendor-specific, not subject to
standardization. It appears that there is a continuing debate on
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whether the configuration data should be pushed to the joining device
or whether the device should pull the configuration data down. In
the latter case, the device needs to know about the existence of the
data and the path to reach it before it can act. One way to acquire
this information is through DHCP. DHCPv4 has provided the necessary
options from its beginnings, inheriting them from BOOTP. They have
been recently added to DHCPv6 [RFC5970].
Protocols that can transport configuration data can be classified as
follows: The first class consists of generic file transfer protocols
that can carry configuration data serialized into configuration
files. The second class consists of protocols that manipulate
structured configuration data directly. The structure of the
configuration data is defined by some data model.
In the first class, we find the following file transfer protocols:
o The File Transfer Protocol (FTP) [RFC0959] can be used to move
files containing configuration data. It can be secured by running
FTP over TLS [RFC4217].
o The Trivial File Transfer Protocol (TFTP) [RFC1350] has been used
extensively to load boot images over the network. However, it
does not provide security and the only option is to rely on IP
layer security (IPsec).
o The Hypertext Transfer Protocol (HTTP) [RFC2616] can be used to
transfer documents containing configuration data. It is commonly
secured by running HTTP over TLS [RFC2817] [RFC2818].
o The SSH File Transfer Protocol (SFTP) [I-D.ietf-secsh-filexfer]
provides roughly the same services as FTP but runs over SSH and
thus utilizes the security services provided by SSH.
o UNIX utilities to transfer files such as RCP and SCP provide
limited flexibility and they differ in their degree of integration
with SSH.
o The Control And Provisioning of Wireless Access Points (CAPWAP)
protocol [RFC5415] can be used to control the download of images.
CAPWAP can be secured by running CAPWAP over DTLS.
In the second class, we find the following configuration protocols:
o Version 3 of the Simple Network Management Protocol (SNMPv3)
[RFC3411]-[RFC3418] can be used to manipulate MIB objects and to
carry event notifications. It has its own security protocol (USM)
but can also run over SSH [RFC5592], TLS, or DTLS [RFC5953].
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o The Common Open Policy Service for Policy Provisioning protocol
(COPS-PR) [RFC3084] was designed to provision structured policy
information from a Policy Decision Point (PDP) to a Policy
Enforcement Point (PEP). The COPS protocol [RFC2748] provides an
integrity object that can achieve authentication, message
integrity, and replay prevention. Optionally, COPS and COPS-PR
can run over TLS.
o The NETCONF protocol [RFC4741] provides mechanisms to install,
manipulate, and delete the configuration of network devices. A
protocol extension provides an asychronous even notification
delivery mechanism [RFC5277]. NETCONF by default runs over SSH
but can also run over transports secured by TLS.
o The Control And Provisioning of Wireless Access Points protocol
(CAPWAP) [RFC5415] supports the discovery of so called Access
Controller (AC) by Wireless Termination Points (WTPs) and the
configuration of WTPs by an AC. While CAPWAP can be extended to
configure other devices, its main focus are WTPs. The CAPWAP
protocol is protected by using DTLS after the discovery phase.
Table 1 lists the protocols plus their security options. Note that
all protocols can be secured at the IP layer by using IPsec and hence
this is not mentioned explicitly in Table 1.
+-----------+--------------+----------------------------------------+
| Transport | Security | Data Transfer Model |
+-----------+--------------+----------------------------------------+
| FTP | TLS | Push or pull of (configuration) files |
| TFTP | | Push or pull of (configuration) files |
| HTTP | TLS | Push or pull of (configuration) files |
| SFTP | SSH | Push or pull of (configuration) files |
| RCP | | Push or pull of (configuration) files |
| SCP | SSH | Push or pull of (configuration) files |
| CAPWAP | DTLS | AC pushes configuration parameters, |
| | | WTP pulls software |
| SNMPv3 | USM [SSH, | Push of structured configuration |
| | TLS, DTLS] | parameters, event notifications |
| COPS-PR | TLS | Push of structured policy information |
| NETCONF | SSH [TLS] | Push of structured configuration data, |
| | | event notifications |
+-----------+--------------+----------------------------------------+
Table 1: Protocols for transporting configuration data
SNMPv3, NETCONF, and COPS-PR carry structured data specified in pre-
defined data models. SNMPv3 and COPS-PR have size limitations on the
data objects and thus make the transport of larger software images
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difficult. NETCONF does not suffer from hard size restrictions and
can in principle carry software images inline. However, there is
currently no work in progress to standardize the transfer of software
images over NETCONF. An advantage of NETCONF over SNMPv3 and CAPWAP
is the support or concurrent updates through locking mechanisms and
the support of network wide configuration change transactions through
the confirmed commit capability. CAPWAP combines the functions of
configuration parameter transport and software download. The
parameter transport aspect lacks the generality offered by SNMP,
NETCONF, and COPS-PR, since the parameters are specified within the
protocol specification itself. The remaining transports are
independent of the nature of the information being transferred.
7. Configuration Auditing
To complete the process, it must be possible to audit the
configuration status of the device in some detail. This is likely to
begin even before all the configuration data has been downloaded.
For instance, configuration management may wish to collect basic
information such as the MAC addresses of the device's interfaces, the
link-local addresses assigned to them, and similar information for
the neighbours of the joining device.
SNMP and SNMP MIB modules are obviously one way to collect this
information. NETCONF [RFC4741] is an alternative, but the necessary
data models have to be defined. YANG modules for NETCONF [RFC6020]
can be prepared relatively quickly from existing SNMP MIB modules by
translating the SNMP modules into YANG modules. Work to standardize
such translations is currently being chartered in the NETMOD working
group.
Another important auditing activity is the analysis of system events.
The SYSLOG protocol [RFC5424] is widely used for this purpose but
SNMPv3 and NETCONF can ship event notifications as well.
Translations of SNMP notifications into structured SYSLOG messages
and vice versa do exist [RFC5675] [RFC5676]. NETCONF can carry
SYSLOG content as well [RFC5277].
8. Missing Specifications
This document discussed the automated configuration of devices in
service provider networks. Several gaps were identified requiring
further specification:
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G1: Definition of stable unique device identifiers such as the work
described in [I-D.ietf-dhc-duid-uuid].
G2: Definition of a DHCP option to provide the IPv4/IPv6 address of
a configuration server. Such an option allows a joining device
to pickup the configuration server's address as part of the DHCP
exchange. This is particularly interesting for Intra-domain
Scenarios.
G3: Definition of DNS SRV records for locating configuration
servers. Such an option allows a joining device to lookup the
configuration server's in the DNS; this is particularly useful
in an Inter-domain Scenario.
G4: Definition of a SLP template for discovering configuration
servers. Such a template is useful only in environments where
SLP is used also for other purposes.
G5: Definition of NETCONF data models to support the download /
update of software images through NETCONF.
G6: Definition of NETCONF data models for collecting basic system
information and integrity information (e.g., checksums of
software images) and for sending configuration management
related notifications.
G7: Some management protocols do not provide mechanisms for devices
to initiate a secure communication channel with a management
system ("call home").
9. Security Considerations
The security of a configuration management solution is of crucial
importance. Section 6 discusses the security options of several
protocols that might be used. The relevant protocol definitions
should be consulted to learn more about the specific security aspects
of the various protocols.
It should be noted that some steps in the described process, in
particular the bootstrapping phase, may not be secure and it is thus
important to verify the identity of the device and the identity of
the configuration server when a secure connection to a configuration
server is established. Usage of IPsec, which focuses on securing the
IP layer, may not be sufficient for this.
During the choice of protocols, the available security mechanisms and
the required key management infrastructures may play a major role in
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the selection of protocols. Easy integration into existing
Authentication, Authorization and Accounting (AAA) infrastructures
can significantly reduce the operational costs associated with the
security management of the configuration system.
While [I-D.sarikaya-core-sbootstrapping] discusses security
bootstrapping mechanisms in the context of constrained devices, many
of the mechanisms are also applicable for bootstrapping security in
normal devices.
Finally, [RFC6092] discusses security capabilities for customer
premises equipment providing residential IPv6 Internet service.
10. IANA Considerations
This memo includes no request to IANA.
11. Contributors
Thanks to Mehmet Ersue, Yiu Lee, and Cathy Zhou Ersue for help in
preparing this memo.
12. Informative References
[I-D.ietf-dhc-duid-uuid]
Narten, T. and J. Johnson, "Definition of the UUID-based
DHCPv6 Unique Identifier (DUID-UUID)",
draft-ietf-dhc-duid-uuid-02 (work in progress),
December 2010.
[I-D.ietf-secsh-filexfer]
Galbraith, J. and O. Saarenmaa, "SSH File Transfer
Protocol", draft-ietf-secsh-filexfer-13 (work in
progress), July 2006.
[I-D.sarikaya-core-sbootstrapping]
Sarikaya, B., Ohba, Y., Cao, Z., and R. Cragie, "Security
Bootstrapping of Resource-Constrained Devices",
draft-sarikaya-core-sbootstrapping-01 (work in progress),
January 2011.
[RFC0951] Croft, B. and J. Gilmore, "Bootstrap Protocol", RFC 951,
September 1985.
[RFC0959] Postel, J. and J. Reynolds, "File Transfer Protocol",
Tsou, et al. Expires August 12, 2011 [Page 15]
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STD 9, RFC 959, October 1985.
[RFC1350] Sollins, K., "The TFTP Protocol (Revision 2)", STD 33,
RFC 1350, July 1992.
[RFC1531] Droms, R., "Dynamic Host Configuration Protocol",
RFC 1531, October 1993.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",
RFC 2131, March 1997.
[RFC2608] Guttman, E., Perkins, C., Veizades, J., and M. Day,
"Service Location Protocol, Version 2", RFC 2608,
June 1999.
[RFC2609] Guttman, E., Perkins, C., and J. Kempf, "Service Templates
and Service: Schemes", RFC 2609, June 1999.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 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.
[RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for
specifying the location of services (DNS SRV)", RFC 2782,
February 2000.
[RFC2817] Khare, R. and S. Lawrence, "Upgrading to TLS Within
HTTP/1.1", RFC 2817, May 2000.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 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.
[RFC3118] Droms, R. and W. Arbaugh, "Authentication for DHCP
Messages", RFC 3118, June 2001.
[RFC3139] Sanchez, L., McCloghrie, K., and J. Saperia, "Requirements
for Configuration Management of IP-based Networks",
RFC 3139, June 2001.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
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and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction and Applicability Statements for Internet-
Standard Management Framework", RFC 3410, December 2002.
[RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing Simple Network Management
Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
December 2002.
[RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management
Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.
[RFC3418] Presuhn, R., "Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)", STD 62,
RFC 3418, December 2002.
[RFC3535] Schoenwaelder, J., "Overview of the 2002 IAB Network
Management Workshop", RFC 3535, May 2003.
[RFC3736] Droms, R., "Stateless Dynamic Host Configuration Protocol
(DHCP) Service for IPv6", RFC 3736, April 2004.
[RFC4217] Ford-Hutchinson, P., "Securing FTP with TLS", RFC 4217,
October 2005.
[RFC4251] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Protocol Architecture", RFC 4251, January 2006.
[RFC4252] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, January 2006.
[RFC4253] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Transport Layer Protocol", RFC 4253, January 2006.
[RFC4254] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Connection Protocol", RFC 4254, January 2006.
[RFC4301] Kent, S. and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005.
[RFC4347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security", RFC 4347, April 2006.
[RFC4741] Enns, R., "NETCONF Configuration Protocol", RFC 4741,
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December 2006.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[RFC5006] Jeong, J., Park, S., Beloeil, L., and S. Madanapalli,
"IPv6 Router Advertisement Option for DNS Configuration",
RFC 5006, September 2007.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC5277] Chisholm, S. and H. Trevino, "NETCONF Event
Notifications", RFC 5277, July 2008.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008.
[RFC5415] Calhoun, P., Montemurro, M., and D. Stanley, "Control And
Provisioning of Wireless Access Points (CAPWAP) Protocol
Specification", RFC 5415, March 2009.
[RFC5424] Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009.
[RFC5592] Harrington, D., Salowey, J., and W. Hardaker, "Secure
Shell Transport Model for the Simple Network Management
Protocol (SNMP)", RFC 5592, June 2009.
[RFC5675] Marinov, V. and J. Schoenwaelder, "Mapping Simple Network
Management Protocol (SNMP) Notifications to SYSLOG
Messages", RFC 5675, October 2009.
[RFC5676] Schoenwaelder, J., Clemm, A., and A. Karmakar,
"Definitions of Managed Objects for Mapping SYSLOG
Messages to Simple Network Management Protocol (SNMP)
Notifications", RFC 5676, October 2009.
[RFC5730] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
STD 69, RFC 5730, August 2009.
[RFC5953] Hardaker, W., "Transport Layer Security (TLS) Transport
Model for the Simple Network Management Protocol (SNMP)",
RFC 5953, August 2010.
[RFC5970] Huth, T., Freimann, J., Zimmer, V., and D. Thaler, "DHCPv6
Options for Network Boot", RFC 5970, June 2010.
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[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010.
[RFC6092] Woodyatt, J., "Recommended Simple Security Capabilities in
Customer Premises Equipment (CPE) for Providing
Residential IPv6 Internet Service", RFC 6092,
January 2011.
[TR_069] Blackford, J., Ed., Kirksey, H., Ed., and W. Lupton, Ed.,
"CPE WAN Management Protocol", Broadband Forum TR-069,
November 2010.
[TS_32_500]
3rd Generation Partnership Project, "3rd Generation
Partnership Project; Technical Specification Group
Services and System Aspects; Telecommunication Management;
Self-Organizing Networks (SON); Concepts and requirements
(Release 9)", 3GPP TS 32.500, 2010.
[TS_36_300]
3rd Generation Partnership Project, "3rd Generation
Partnership Project; Technical Specification Group Radio
Access Network; Evolved Universal Terrestrial Radio Access
(E-UTRA) and Evolved Universal Terrestrial Radio Access
Network (E-UTRAN); Overall description; Stage 2 (Release
9)", 3GPP TS 36.300, 2010.
Appendix A. Open Issues
The document should discuss the usage of VPNs in the Inter-domain
scenario.
Authors' Addresses
Tina Tsou
Huawei Technologies
Bantian, Longgang District
Shenzhen 518129
P.R. China
Email: tena@huawei.com
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Juergen Schoenwaelder (editor)
Jacobs University Bremen
Campus Ring 1
Bremen 28759
Germany
Email: j.schoenwaelder@jacobs-university.de
Yang Shi
Hangzhou H3C Tech. Co., Ltd.
Beijing R&D Center of H3C, Digital Technology Plaza,
NO.9 Shangdi 9th Street, Haidian District,
Beijing
China(100085)
Phone: +86 010 82775276
Email: young@h3c.com
Tom Taylor (editor)
Huawei Technologies
1852 Lorraine Ave.
Ottawa K1H 6Z8
Canada
Email: tom111.taylor@bell.net
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