Manufacturer Usage Description SpecificationCisco SystemsRichtistrasse 7WallisellenCH-8304Switzerland+41 44 878 9200lear@cisco.comCisco Systems55 Cambridge ParkwayCambridge1057United States+1 617 621 1904rdroms@cisco.comAvaya26, HaRokhmim Str., Bldg. DHolon5885849Israel+972-3-645-8414dromasca@avaya.comInternet-DraftThis memo specifies the necessary components to implement manufacturer
usage descriptions (MUD). This includes two YANG modules, IPv4 and IPv6
DHCP options, an LLDP TLV, a URL suffix specification, an X.509 certificate
extension and a means to sign and verify the descriptions.The Internet has largely been constructed on general purpose
computers; those devices that may be used for a purpose that is
specified by those who buy the device. presumed that an
end device would be most capable of protecting itself. This made
sense when the typical device was a workstation or a mainframe, and it
continues to make sense for general purpose computing devices today,
including laptops, smart phones, and tablets. discusses design patterns for, and poses questions about,
smart objects. Let us then posit a group of objects that are
specifically not general purpose computers. These devices therefore
have a purpose to their use. By definition, therefore, all other
purposes are NOT intended. The combination of these two statements
can be restated as a manufacturer usage description (MUD) that can
be applied at various points within a network. Although this memo may
seem to stress access requirements, usage intent also consists of
quality of service needs a device may have.We use the notion of “manufacturer” loosely in this context, to simply
mean the entity or organization that will state how a device is
intended to be used. In the context of a lightbulb, this might indeed
be the lightbulb manufacturer. In the context of a smarter device
that has a built in Linux stack, it might be integrator of that
device. The key points are that the device itself is expected to
serve a limited purpose, and that there may exist an organization in
the supply chain of that device that will take responsibility for
informing the network about that purpose.The converse statement holds that general computing systems will
benefit very little from MUD, as their manufacturers cannot envision a
specific communication pattern to describe.The intent of MUD is to therefore solve for the following problems:Substantially reduce the threat surface on a device entering a
network to those communications intended by the manufacturer.Provide for a means to scale network policies to the ever-increasing
number types of devices in the network.Provide a means to address at least some vulnerabilities in a way
that is faster than it might take to update systems. This will be
particularly true for systems that are no longer supported by their
manufacturer.Keep the cost of implementation of such a system to the bare minimum.No matter how good a MUD-enabled network is, it will never replace the
need for manufacturers to patch vulnerabilities. It may, however,
provide network administrators with some additional protection when
those vulnerabilities exist.A light bulb is intended to light a room. It may be remotely
controlled through the network; and it may make use of a rendezvous
service of some form that an app on smart phone accesses. What we can
say about that light bulb, then, is that all other network access is
unwanted. It will not contact a news service, nor speak to the
refrigerator, and it has no need of a printer or other devices. It
has no Facebook friends. Therefore, an access list applied to it that
states that it will only connect to the single rendezvous service will
not impede the light bulb in performing its function, while at the same
time allowing the network to provide both it and other devices an
additional layer of protection.The notion of intended use is in itself not new. Network
administrators apply access lists every day to allow for only such
use. This notion of white listing was well described by Chapman and
Zwicky in . Programmatically profiling systems have existed
for years as well. These systems make use of heuristics that take
at least some time to assert what a system is.A system could just as easily tell the network what sort of protection
it requires without going into what sort of system it is. This would,
in effect, be the converse of . In seeking a general
purpose solution, however, we assume that a device has so few
capabilities that it will implement the least necessary capabilities
to function properly. This is a basic economic constraint. Unless
the network would refuse access to such a device, its developers would
have no reason to implement such an approach. To date, such an
assertion has held true.Our work begins, therefore, with the device emitting a Universal
Resource Locator (URL) . This URL may serves both to
classify the device type and to provide a means to locate a policy
file.In this memo three means are defined to emit the MUD URL. One is a
DHCP option, that the DHCP client uses to inform
the DHCP server. The DHCP server may take further actions, such as
retrieve the URL or otherwise pass it along to network management
system or controller. The other method defined is an X.509
constraint. The IEEE has developed that provides a
certificate-based approach to communicate device characteristics,
which itself relies on . The MUD URL extension is
non-critical, as required by IEEE 802.1AR. Finally, an LLDP frame is
defined.When the MUD URL is resolved, the MUD controller retrieves a file that
describes what sort of communications a device is designed to have.
The manufacturer may specify either specific hosts for cloud based
services or certain classes for access within an operational network.
An example of a class might be “devices of a specified manufacturer
type”, where the manufacturer type itself is indicated simply by the
authority of the MUD URL. Another example might to allow or disallow
local access. Just like other policies, these may be combined. For
example:To add a bit more depth that should not be a stretch of anyone’s
imagination, one could also make use of port-based access lists. Thus
a printer might have a description that states:In this way anyone can print to the printer, but local access would
be required for the management interface.The files that are retrieved are intended to be closely aligned to
existing network architectures so that they are easy to deploy. We
make use of YANG because of the time and effort spent to
develop accurate and adequate models for use by network devices. JSON
is used as a serialization for compactness and readability, relative
to XML.The YANG modules specified here are extensions of
. The extensions to this model allow for
a manufacturer to express classes of systems that a manufacturer would
find necessary for the proper function of the device. Two modules are
specified. The first module specifies a means for domain names to be
used in ACLs so that devices that have their controllers in the cloud
may be appropriately authorized with domain names, where the mapping
of those names to addresses may rapidly change.The second module abstracts away IP addresses into certain classes
that are instantiated into actual IP addresses through local
processing. Through these classes, manufacturers can specify how the
device is designed to communicate, so that network elements can be
configured by local systems that have local topological knowledge.
That is, the deployment populates the classes that the manufacturer
specifies.Because manufacturers do not know who will be using their devices, it
is important for functionality referenced in usage descriptions to be
relatively ubiquitous, and therefore, mature. Therefore, only a
a limited subset YANG-based configuration of is permitted in a MUD file.
manufacturer usage description.
a file containing YANG-based JSON that describes a recommended behavior.
a web server that hosts a MUD file.
the system that requests and receives the MUD file from the MUD
server. After it has processed a MUD file it may direct changes to
relevant network elements.
a URL that can be used by the MUD controller to receive the MUD file.The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL
NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and
“OPTIONAL” in this document are to be interpreted as described in
.With these components laid out we now have the basis for an
archicture. This leads us to ASCII art.In the above diagram, the switch or router collects MUD URLs and
forwards them to the network management system for processing. This
happens in different ways, depending on how the URI is communicated.
For instance, in the case of DHCP, the DHCP server might receive the
URI and then process it. In the case of IEEE 802.1X, the switch
would tunnel the URI to the authentication server, who would then
process it.The information returned by the web site is valid for the duration of
the device’s connection, or as specified in the description. Thus if the
device is mobile, when it moves on, any configuration in the switch is
removed. Similarly, from time to time the description may be
refreshed, based on new capabilities or communication patterns or
vulnerabilities.The web site is typically run by or on behalf of the manufacturer.
Its domain name is that of the authority found in the MUD URL. For
legacy cases where Things cannot emit a URL, if the switch is able to
determine the appropriate URI, it may proxy it, the trivial cases
being a map between some registered device or port and a URL.A MUD file consists of JSON based on a YANG model. For purposes of
MUD, the elements that can be modified are access lists as augmented
by this model. The MUD file is limited to the serialization of a
small number of YANG schema, including the models specified in the
following documents:Publishers of MUD files MUST NOT include other elements except as
described in , and MUST only contain information
relevant to the device being described. Devices parsing MUD files
MUST cease processing if they find other elements.This module is structured into three parts. The first container holds
information that is relevant to retrieval and validity of the MUD file
itself. The second container augments the access list to indicate
direction the ACL is to be applied. The final container augments the
matching container of the ACL model to add several elements that are
relevant to the MUD URL, or other otherwise abstracted for use within
a local environment.The following elements are defined.This is a date-and-time value of the last time the MUD file was
updated. This is akin to a version number. Its form is taken from
which, for those keeping score, turn was taken from
Section 5.6 of , which was taken from .This is a URL that should point to the previous MUD URL for
auditing purposes. Because it should not be necessary to resign a MUD
file when a new one is released, the archival location of a current
MUD file should be identified prior to its release. Note the
signature file MUST also be available. For example, if
previous-mud-file is set to “https://example.com/.mud/v1/xxx”, the
corresponding signature would be found at
“https://example.com/.mud/v1/xxx.p7s”.This uint32 is the period of time in hours that a network management
station MUST wait since its last retrieval before checking for an
update. It is RECOMMENDED that this value be no less than 24 and no
more than 1440 for any device that is supported.This optional element refers to the URL that should be used to
resolve the location any MASA service, as specified in
.This boolean is an indication from the manufacturer to the network
administrator as to whether or not the device is supported. In this
context a device is said to be supported if the manufacturer might
issue an update to the device or if the manufacturer might update the
MUD file. describes access-lists but does not
attempt to indicate where they are applied as that is handled
elsewhere in a configuration. However, in this case, a MUD
file must be explicit in describing the communcation pattern of a
device, and that includes indicating what is to be permitted or denied
in either direction of communication. This element takes a single
value of either “to-device” or “from-device”, based on a typedef
“direction”.This element consists of a hostname that would be matched against the
authority section of another device’s MUD URL.This is an equivalent for when the manufacturer element is used
to indicate the authority that is found in another device’s MUD URL
matches that of the authority found in this device’s MUD URL.This string matches the one and only segment following the
authority section of the MUD URL. It refers to a model that is unique
within the context of the authority. It may also include product
version information. Thus how this field is constructed is entirely a
local matter for the manufacturer.This null-valued element expands to include local networks. Its
default expansion is that packets must not traverse toward a default
route that is received from the router.This URI specifies a value that a controller will register with the
network management station. The element then is expanded to the set
of hosts that are so registered.In addition, some meta information is defined in order to determine
when a usage description should be refreshed.When applied this matches packets when the flow was initiated in the
corresponding direction. provides guidance for IPv6 guidance
best practices. While that document is scoped specifically to IPv6,
its contents are applicable for IPv4 as well. When this flag is set,
and the system has no reason to believe a flow has been initiated it
MUST drop the packet. This match SHOULD be applied with specific
transport parameters, such as protocol.To keep things relatively simple in addition to whatever definitions
exist, we also apply two additional default behaviors:Anything not explicitly permitted is denied.Local DNS, DHCP, and NTP are, by default, permitted to and from the device.To begin with, MUD takes full advantage of both the https: scheme and
the use of .well-known. HTTPS is important in this case because a man
in the middle attack could otherwise harm the operation of a class of
devices. .well-known is used because we wish to add additional
structure to the URL. And so the URL appears as follows:mud-rev signifies the version of the manufacturer usage description
file. This memo specifies “v1” of that file. Later versions may
permit additional schemas or modify the format.“model” represents a device model as the manufacturer wishes to
represent it. It could be a brand name or something more specific.
It also may provide a means to indicate what version the product is.
Specifically if it has been updated in the field, this is the place
where evidence of that update would appear. The field should be
changed when the intended communication patterns of a device change.
While from a controller standpoint, only comparison and matching
operations are safe, it is envisioned that updates will require some
administrative review. Processing of this URL occurs as specified in
and .This module specifies an extension to IETF-ACL model such that domain
names may be referenced by augmenting the “matches” element.
Different implementations may deploy differing methods to maintain the
mapping between IP address and domain name, if indeed any are needed.
However, the intent is that resources that are referred to using a
name should be authorized (or not) within an access list.The structure of the change is as follows:The choice of this particular point in the access-list model is based
on the assumption that we are in some way referring to IP-related
resources, as that is what the DNS returns. A domain name in our
context is defined in .The following elements are defined.The argument corresponds to a domain name of a source as specified by
inet:host. Depending on how the model is used, it may or may not be
resolved, as required by the implementation and circumstances.The argument corresponds to a domain name of a destination as
specified by inet:host. Depending on how the model is used, it may or
may not be resolved, as required by the implementation and
circumstances.This example contains two access lists that are intended to provide
outbound access to a cloud service on TCP port 443.The IPv4 MUD URL client option has the following format:Code OPTION_MUD_URL_V4 (TBD) is assigned by IANA. len is a single
octet that indicates the length of the URL in octets. MUD URL is a
URL. The length of a MUD URL does not exceed 255 bytes.The IPv6 MUD URL client option has the following format:OPTION_MUD_URL_V6 (TBD; assigned by IANA).option-length contains the length of the URL in octets. The length
MUST NOT exceed 255 octets.The intent of this option is to provide both a new device classifier
to the network as well as some recommended configuration to the
routers that implement policy. However, it is entirely the purview of
the network system as managed by the network administrator to decide
what to do with this information. The key function of this option is
simply to identify the type of device to the network in a structured
way such that the policy can be easily found with existing toolsets.A DHCP client MAY emit either a DHCPv4 or DHCPv6 option or both.
These options singletons, as specified in . Because clients are
intended to have at most one MUD URL associated with them, they may
emit at most one MUD URL option via DHCPv4 and one MUD URL option via
DHCPv6. In the case where both v4 and v6 DHCP options are emitted,
the same URL MUST be used.Clients SHOULD log or otherwise report improper acknowledgments from
servers, but they MUST NOT modify their MUD URL configuration based on
a server’s response. The server’s response is only an acknowledgment
that the server has processed the option, and promises no specific
network behavior to the client. In particular, it may not be possible
for the server to retrieve the file associated with the MUD URL,
or the local network administration may not wish to use the usage
description. Neither of these situations should be considered in any
way exceptional.A DHCP server may ignore these options or take action based on receipt
of these options. For purposes of debugging, if a server successfully
parses the option and the URL, it MUST return the option with the same
URL as an acknowledgment. Even in this circumstance, no specific
network behavior is guaranteed. When a server consumes this option,
it will either forward the URL and relevant client information to a
network management system (such as the giaddr), or it will retrieve
the usage description by resolving the URL.DHCP servers may implement MUD functionality themselves or they may
pass along appropriate information to a network management system or
controller. A DHCP server that does process the MUD URL MUST adhere to
the process specified in and to validate the
TLS certificate of the web server hosting the MUD file. Those servers
will retrieve the file, process it, create and install the necessary
configuration on the relevant network element. Servers SHOULD monitor the
gateway for state changes on a given interface. A DHCP server that
does not provide MUD functionality and has forwarded a MUD URL to a
network management system MUST notify the network management of any
corresponding change to the DHCP state of the client (such as
expiration or explicit release of a network address lease).There are no additional requirements for relays. provides a procedure and means to specify extensions to
X.509 certificates. The MUD URL is a non-critical Certificate
extension that points to an on-line Manufacturer Usage Description
concerning the certificate subject. This extension contains a single
Uniform Resource Identifier (URI). Internationalized Resource
Identifiers must be represented as URI’s in the way described in RFC
5280, section 7.4.The choice of id-pe is based on guidance found in Section 4.2.2 of
:The MUD URL is precisely that: online information about the particular
subject.The new extension is identified as follows:– The MUD URL extension
id-pe-mud-url OBJECT IDENTIFER ::= { id-pe TBD }The extension returns a single value:mudURLSyntax ::= IA5String – for use with MUD architecture.The semantics of the URI are defined .The IEEE802.1AB Link Layer Discovery Protocol (LLDP) is a
one hop vendor-neutral link layer protocols used by end hosts network
devices for advertising their identity, capabilities, and neighbors on
an IEEE 802 local area network. Its Type-Length-Value (TLV) design
allows for ‘vendor-specific’ extensions to be defined. IANA has a
registered IEEE 802 organizationally unique identifier (OUI) defined
as documented in . The MUD LLDP extension uses a subtype
defined in this document to carry the MUD URL.The LLDP vendor specific frame has the following format:where:TLV Type = 127 indicates a vendor-specific TLVlen – indicates the TLV string lengthOUI = 00 00 5E is the organizationally unique identifier of IANAsubtype = 1 (to be assigned by IANA for the MUD URL)MUD URL – the length MUST NOT exceed 256 octets (consistent with
the DHCP option defined in )The intent of this extension is to provide both a new device
classifier to the network as well as some recommended configuration to
the routers that implement policy. However, it is entirely the
purview of the network system as managed by the network administrator
to decide what to do with this information. The key function of this
extension is simply to identify the type of device to the network in a
structured way such that the policy can be easily found with existing
toolsets.Hosts, routers, or other network devices that implement this option
are intended to have at most one MUD URL associated with them, so they
may transmit at most one MUD URL value.Hosts, routers, or other network devices that implement this option
may ignore these options or take action based on receipt of these
options. For example they may fill in information in the respective
extensions of the LLDP Management Information Base (LLDP MIB). LLDP
operates in a one-way direction. LLDPDUs are not exchanged as
information requests by one device and response sent by another
device. The other devices do not acknowledge LLDP information received
from a device. No specific network behavior is guaranteed. When a
device consumes this extension, it may either forward the URL and
relevant remote device information to a network management system, or
it will retrieve the usage description by resolving the URL.Because MUD files contain information that may be used to configure
network access lists, they are sensitive. To insure that they have
not been tampered with, it is important that they be signed. We make
use of DER-encoded Cryptographic Message Syntax (CMS) for
this purpose.A MUD file MUST be signed using CMS as an opaque binary object. In
order to make successful verification more likely, intermediate
certificates SHOULD be included. If the device that is being
described supports IEEE 802.1AR, its manufacturer certificate and the
certificate in the MUD file MUST share a common trust anchor in
order to insure that manufacturer of the device is also the provider
of the MUD file. The signature is stored at the same location as the
MUD URL but with the suffix of “.p7s”. Signatures are transferred
using content-type “Application/pkcs7-signature”.For example:Note: A MUD file may need to be resigned if the signature expires.Prior to retrieving a MUD file the MUD controller SHOULD retrieve the
MUD signature file using the MUD URL with a suffix of “.p7s”. For
example, if the MUD URL is
“https://example.com/.well-known/v1/modela”, the MUD signature URL
will be “https://example.com/.well-known/v1/modela.p7s”.Upon retrieving a MUD file, a MUD controller MUST validate the
signature of the file before continuing with further processing. A
MUD controller SHOULD produce an error and it MUST cease all
processing of that file if the signature cannot be validated. If the
MUD controller has received the MUD URL via IEEE 802.1AR containing an
IDevID (a manufacturer certificate), it MUST further confirm that the
manufacturer certificate and that of the MUD file share a common trust
anchor.For Example:Note the additional step of verifying the common trust root.One of our design goals is to see that MUD files are able to be
understood by as broad a cross-section of systems as is possible.
Coupled with the fact that we have also chosen to leverage existing
mechanisms, we are left with no ability to negotiate extensions and a
limited desire for those extensions in any event. A such, a
two-tier extensibility framework is employed, as follows:At a coarse grain, a protocol version is included in a MUD URL.
This memo specifies MUD version 1. Any and all changes are
entertained when this version is bumped. Transition approaches
between versions would be a matter for discussion in future versions.At a finer grain, only extensions that would not incur additional
risk to the device are permitted. Specifically, augmenting of the
meta-information container is permitted with the understanding that
such additions may be ignored. In addition, augmentation of the ACL
model is permitted so long as it remains safe for a given ACE to be
ignored by the MUD Controller or the network elements it configures.
Most specifically, is is not permitted to include as an augmentation
that modifies “deny” behavior without bumping the version.
Furthermore, implementations that are not able to parse a component
of the ACE array MUST ignore the entire array entry (e.g., not the
entire array) and MAY ignore the entire MUD file.Based on the means a URL is procured, a device may be able to lie
about what it is, thus gaining additional network access. There are
several means to limit risk in this case. The most obvious is to only
believe devices that make use of certificate-based authentication such
as IEEE 802.1AR certificates. When
those certificates are not present, devices claiming to be of a
certain manufacturer SHOULD NOT be included in that manufacturer
grouping without additional validation of some form. This will
occur when it makes use of primitives such as “manufacturer” for the
purpose of accessing devices of a particular type.Network management systems SHOULD NOT deploy a usage description for a
device with the same MAC address that has indicated a change of
authority without some additional validation (such as review of the
class). New devices that present some form of unauthenticated MUD URL
SHOULD be validated by some external means when they would be
otherwise be given increased network access.It may be possible for a rogue manufacturer to inappropriately
exercise the MUD file parser, in order to exploit a vulnerability.
There are three recommended approaches to address this threat. The
first is to validate the signature of the MUD file. The second is to
have a system do a primary scan of the file to ensure that it is both
parseable and believable at some level. MUD files will likely be
relatively small, to start with. The number of ACEs used by any given
device should be relatively small as well. Second, it may be useful
to limit retrieval of MUD URLs to only those sites that are known to
have decent web reputations.Use of a URL necessitates the use of domain names. If a domain name
changes ownership, the new owner of that domain may be able to provide
MUD files that MUD controllers would consider valid. There are a few
approaches that can mitigate this attack. First, MUD file servers
SHOULD cache certificates used by the MUD file server. When a new
certificate is retrieved for whatever reason, the MUD controller
should check to see if ownership of the domain has changed. A fair
programmatic approximation of this is when the name servers for the
domain have changed. If the actual MUD file has changed, the
controller MAY check the WHOIS database to see if registration
ownership of a domain has changed. If a change has occured, or if for
some reason it is not possible to determine whether ownership has
changed, further review may be warranted. Note, this remediation does
not take into account the case of a device that was produced long ago
and only recently fielded, or the case where a new MUD controller has
been installed.IANA is requested to allocated the DHCPv4 and v6 options as specified
in .The IANA is requested to assign a value for id-pe-mud-uri in the “SMI
Security for PKIX Certificate Extension” Registry. Its use is
specified in .The IANA is requested to register the URL suffix of “mud” as follows:o URI Suffix: “mud”
o Specification documents: this document
o Related information: n/aThe following media-type is defined for transfer of MUD file:IANA is requested to create a new registry for IANA Link Layer
Discovery Protocol (LLDP) TLV subtype values. The recommended policy
for this registry is Expert Review. The maximum number of entries in
the registry is 256.IANA is required to populate the initial registry with the value:LLDP subtype value = 1Description = the Manufacturer Usage Description (MUD) Uniform Resource Locator (URL)Reference = < this document >The authors would like to thank Einar Nilsen-Nygaard, Bernie Volz, Tom
Gindin, Brian Weis, Sandeep Kumar, Thorsten Dahm, John
Bashinski, Steve Rich, Jim Bieda, and Dan Wing for their valuable
advice and reviews. The remaining errors in this work are entirely
the responsibility of the author.Key words for use in RFCs to Indicate Requirement LevelsIn many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.Uniform Resource Identifier (URI): Generic SyntaxA Uniform Resource Identifier (URI) is a compact sequence of characters that identifies an abstract or physical resource. This specification defines the generic URI syntax and a process for resolving URI references that might be in relative form, along with guidelines and security considerations for the use of URIs on the Internet. The URI syntax defines a grammar that is a superset of all valid URIs, allowing an implementation to parse the common components of a URI reference without knowing the scheme-specific requirements of every possible identifier. This specification does not define a generative grammar for URIs; that task is performed by the individual specifications of each URI scheme. [STANDARDS-TRACK]YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK]Network Access Control List (ACL) YANG Data ModelThis document describes a data model of Access Control List (ACL) basic building blocks.Bootstrapping Remote Secure Key Infrastructures (BRSKI)This document specifies automated bootstrapping of a remote secure key infrastructure (BRSKI) using vendor installed IEEE 802.1AR manufacturing installed certificates, in combination with a vendor based service on the Internet. Before being authenticated, a new device has only link-local connectivity, and does not require a routable address. When a vendor provides an Internet based service devices can be redirected to a local service. In limited/ disconnected networks or legacy environments we describe a variety of options that allow bootstrapping to proceed. Support for lower security models, including devices with minimal identity, is described for legacy reasons but not encouraged.HTTP Over TLSThis memo describes how to use Transport Layer Security (TLS) to secure Hypertext Transfer Protocol (HTTP) connections over the Internet. This memo provides information for the Internet community.Common YANG Data TypesThis document introduces a collection of common data types to be used with the YANG data modeling language. This document obsoletes RFC 6021.Dynamic Host Configuration ProtocolThe Dynamic Host Configuration Protocol (DHCP) provides a framework for passing configuration information to hosts on a TCPIP network. DHCP is based on the Bootstrap Protocol (BOOTP), adding the capability of automatic allocation of reusable network addresses and additional configuration options. [STANDARDS-TRACK]Dynamic Host Configuration Protocol for IPv6 (DHCPv6)Guidelines for Creating New DHCPv6 OptionsThis document provides guidance to prospective DHCPv6 option developers to help them create option formats that are easily adoptable by existing DHCPv6 software. It also provides guidelines for expert reviewers to evaluate new registrations. This document updates RFC 3315.Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) ProfileThis memo profiles the X.509 v3 certificate and X.509 v2 certificate revocation list (CRL) for use in the Internet. An overview of this approach and model is provided as an introduction. The X.509 v3 certificate format is described in detail, with additional information regarding the format and semantics of Internet name forms. Standard certificate extensions are described and two Internet-specific extensions are defined. A set of required certificate extensions is specified. The X.509 v2 CRL format is described in detail along with standard and Internet-specific extensions. An algorithm for X.509 certification path validation is described. An ASN.1 module and examples are provided in the appendices. [STANDARDS-TRACK]Cryptographic Message Syntax (CMS)This document describes the Cryptographic Message Syntax (CMS). This syntax is used to digitally sign, digest, authenticate, or encrypt arbitrary message content. [STANDARDS-TRACK]Recommended Simple Security Capabilities in Customer Premises Equipment (CPE) for Providing Residential IPv6 Internet ServiceThis document identifies a set of recommendations for the makers of devices and describes how to provide for "simple security" capabilities at the perimeter of local-area IPv6 networks in Internet-enabled homes and small offices. This document is not an Internet Standards Track specification; it is published for informational purposes.Object Identifier Registry for the PKIX Working GroupWhen the Public-Key Infrastructure using X.509 (PKIX) Working Group was chartered, an object identifier arc was allocated by IANA for use by that working group. This document describes the object identifiers that were assigned in that arc, returns control of that arc to IANA, and establishes IANA allocation policies for any future assignments within that arc.IEEE Standard for Local and Metropolitan Area Networks-- Station and Media Access Control Connectivity DiscoveryInstitute for Electrical and Electronics EngineersIAB and IESG Statement on Cryptographic Technology and the InternetIABIESGThe Internet Architecture Board (IAB) and the Internet Engineering Steering Group (IESG), the bodies which oversee architecture and standards for the Internet, are concerned by the need for increased protection of international commercial transactions on the Internet, and by the need to offer all Internet users an adequate degree of privacy. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.Date and Time on the Internet: TimestampsIANA Considerations and IETF Protocol and Documentation Usage for IEEE 802 ParametersSome IETF protocols make use of Ethernet frame formats and IEEE 802 parameters. This document discusses several uses of such parameters in IETF protocols, specifies IANA considerations for assignment of points under the IANA OUI (Organizationally Unique Identifier), and provides some values for use in documentation. This document obsoletes RFC 5342.Architectural Considerations in Smart Object NetworkingThe term "Internet of Things" (IoT) denotes a trend where a large number of embedded devices employ communication services offered by Internet protocols. Many of these devices, often called "smart objects", are not directly operated by humans but exist as components in buildings or vehicles, or are spread out in the environment. Following the theme "Everything that can be connected will be connected", engineers and researchers designing smart object networks need to decide how to achieve this in practice.This document offers guidance to engineers designing Internet- connected smart objects.Port Control Protocol (PCP) Server SelectionThis document specifies the behavior to be followed by a Port Control Protocol (PCP) client to contact its PCP server(s) when one or several PCP server IP addresses are configured.This document updates RFC 6887.Data elements and interchange formats - Information interchange - Representation of dates and timesInternational Organization for StandardizationSecure Device IdentityInstitute for Electrical and Electronics EngineersBuilding Internet FirewallsRFC Editor to remove this section prior to publication.Draft -03 to -04:
* add LLDP extension.
* add Dan Romascanu as co-author.Draft -02 to -03:
* incorporate domain name model.
* discuss extensibility.
* leave placeholder for LLDP TLV.Draft -01 to -02:XML->JSONRemove device versioning information from URLAdd PKIX and DHCP optionsAdd Content-type informationClean up IANA considerations to match registration templatesRalph Droms carried over as author from DHCP option.Signing informationExpanded Security ConsiderationsAdd directionality for both packets and flows.add previous-mud-fileDraft -00 to -01:Add MASA server element