<?xml version="1.0" encoding="US-ASCII"?>

<!DOCTYPE rfc SYSTEM "rfc2629.dtd" [
    <!ENTITY rfc6130 PUBLIC '' 'reference.RFC.6130.xml'>
    <!ENTITY rfc6568 PUBLIC '' 'reference.RFC.6568.xml'>
    <!ENTITY rfc6779 PUBLIC '' 'reference.RFC.6779.xml'>
    <!ENTITY rfc6988 PUBLIC '' 'reference.RFC.6988.xml'>
    <!ENTITY rfc7181 PUBLIC '' 'reference.RFC.7181.xml'>
    <!ENTITY rfc7228 PUBLIC '' 'reference.RFC.7228.xml'>
    <!ENTITY rfc7326 PUBLIC '' 'reference.RFC.7326.xml'>
]>

<rfc submissionType="IETF"
     category="info"
     consensus="yes" 
     number="7548"
     ipr="trust200902">

<?xml-stylesheet type='text/xsl' href='rfc2629.xslt' ?>

<?rfc toc="yes"?>
<?rfc tocompact="yes"?>
<?rfc tocdepth="4"?>
<?rfc symrefs="yes"?>
<?rfc sortrefs="no" ?>
<?rfc compact="yes"?>
<?rfc subcompact="no"?>
<?rfc rfcedstyle="yes"?>

<front>
  <title abbrev="Constrained Management: Use Cases">
    Management of Networks with Constrained Devices: Use Cases
  </title>
  
  <author fullname="Mehmet Ersue" 
          initials="M.E."
          surname="Ersue"  role="editor">
    <organization>Nokia Networks</organization>
    <address>
      <email>mehmet.ersue@nokia.com</email>
    </address>
  </author>
  
  <author fullname="Dan Romascanu" 
          initials="D.R."
          surname="Romascanu" >
    <organization>Avaya</organization>
    <address>
      <email>dromasca@avaya.com</email>
    </address>
  </author>
  
  <author fullname="Juergen Schoenwaelder" 
          initials="J.S."
          surname="Schoenwaelder" >
    <organization>Jacobs University Bremen</organization>
    <address>
      <email>j.schoenwaelder@jacobs-university.de</email>
    </address>
  </author>
  
  <author fullname="Anuj Sehgal" 
          initials="A.S."
          surname="Sehgal" >
    <organization>Jacobs University Bremen</organization>
    <address>
      <email>s.anuj@jacobs-university.de</email>
    </address>
  </author>
  
  <date month="May" year="2015"/>
  <area>Management</area>
  <workgroup>Internet Engineering Task Force</workgroup>
  <keyword>Constrained</keyword>
  <keyword>Management</keyword>
  <keyword>IoT</keyword>
  <keyword>M2M</keyword>
  
  <abstract>
    <t>
      This document discusses use cases concerning the management of
      networks in which constrained devices are involved. A problem
      statement, deployment options, and the requirements on the
      networks with constrained devices can be found in the companion
      document on "Management of Networks with Constrained Devices:
      Problem Statement and Requirements" (RFC 7547).
    </t>
  </abstract>
</front>

<middle>

  <section title="Introduction">
    <t>
      Constrained devices (also known as sensors, smart objects, or smart
  devices) with limited CPU, memory, and power resources can be
  connected to a network.  Such a network of
      constrained devices itself may be constrained or challenged,
      e.g., with unreliable or lossy channels, wireless technologies
      with limited bandwidth and a dynamic topology, needing the
      service of a gateway or proxy to connect to the Internet. In
      other scenarios, the constrained devices can be connected to a
      unconstrained network using off-the-shelf protocol
      stacks. Constrained devices might be in charge of gathering
      information in diverse settings including natural ecosystems,
      buildings, and factories and sending the information to one or more
      server stations.

    </t>
    <t>
      Network management is characterized by monitoring network
      status, detecting faults (and inferring their causes), setting
      network parameters, and carrying out actions to remove faults,
      maintain normal operation, and improve network efficiency and
      application performance.  The traditional network management application
  periodically collects information from a set of managed network
  elements, it processes the collected data, and it presents the
  results to the network management users.  Constrained
      devices, however, often have limited power, have low transmission
      range, and might be unreliable. Such unreliability might arise
      from device itself (e.g., battery exhausted) or from the channel
      being constrained (i.e., low-capacity and high-latency). They
      might also need to work in hostile environments with advanced
      security requirements or need to be used in harsh environments
      for a long time without supervision. Due to such constraints,
      the management of a network with constrained devices offers
      different types of challenges compared to the management of a
      traditional IP network.
    </t>
    <t> 
      This document aims to understand use cases for the management of
      a network in which constrained devices are involved. It
      lists and discusses diverse use cases for management from
      the network as well as from the application point of view. The
      list of discussed use cases is not an exhaustive one since other
      scenarios, currently unknown to the authors, are possible. The
      application scenarios discussed aim to show where networks of
      constrained devices are expected to be deployed. For each
      application scenario, we first briefly describe the
      characteristics followed by a discussion on how network
      management can be provided, who is likely going to be
      responsible for it, and on which time-scale management
      operations are likely to be carried out.
    </t>
    <t> A problem statement, deployment and management topology
      options as well as the requirements on the networks with
      constrained devices can be found in the companion document
      <xref target="RFC7547"/>.
    </t>
    <t>
      This documents builds on the terminology defined in
      <xref target="RFC7228"/> and
      <xref target="RFC7547"/>. <xref target="RFC7228"/> is a base
      document for the terminology concerning constrained devices and
      constrained networks. Some use cases specific to IPv6 over
      Low-Power Wireless Personal Area Networks (6LoWPANs) can be
      found in <xref target="RFC6568"/>.
    </t>
  </section> <!-- Introduction -->

  <section anchor="access" title="Access Technologies">
    <t>
      Besides the management requirements imposed by the different use
      cases, the access technologies used by constrained devices can
      impose restrictions and requirements upon the Network Management
      System (NMS) and protocol of choice.
    </t>
    <t>
      It is possible that some networks of constrained devices might
      utilize traditional unconstrained access technologies for
      network access, e.g., local area networks with plenty of
      capacity. In such scenarios, the constrainedness of the device
      presents special management restrictions and requirements rather
      than the access technology utilized.
    </t>
    <t>
      However, in other situations, constrained or cellular access
      technologies might be used for network access, thereby causing
      management restrictions and requirements to arise as a result of
      the underlying access technologies.
    </t>
    <t>
      A discussion regarding the impact of cellular and constrained
      access technologies is provided in this section since they
      impose some special requirements on the management of
      constrained networks. On the other hand, fixed-line networks
      (e.g., power-line communications) are not discussed here since
      tend to be quite static and do not typically impose any special
      requirements on the management of the network.
    </t>
    <section title="Constrained Access Technologies">
      <t>
        Due to resource restrictions, embedded devices deployed as
        sensors and actuators in the various use cases utilize
        low-power, low-data-rate wireless access technologies such as
        <xref target="IEEE802.15.4" />, Digital Enhanced Cordless Telecommunication (DECT) Ultra Low Energy (ULE), or Bluetooth Low-Energy (BT-LE) for
        network connectivity.
      </t>
      <t>
        In such scenarios, it is important for the NMS to be aware of
        the restrictions imposed by these access technologies to
        efficiently manage these constrained devices. Specifically,
        such low-power, low-data-rate access technologies typically
        have small frame sizes. So it would be important for the NMS
        and management protocol of choice to craft packets in a way
        that avoids fragmentation and reassembly of packets since this
        can use valuable memory on constrained devices.
      </t>
      <t>
        Devices using such access technologies might operate via a
        gateway that translates between these access technologies and
        more traditional Internet protocols. A hierarchical approach
        to device management in such a situation might be useful,
        wherein the gateway device is in-charge of devices connected
        to it, while the NMS conducts management operations only to
        the gateway.
      </t>
    </section>
    <section anchor="access_mobile" title="Cellular Access Technologies">
      <t>
        Machine-to-machine (M2M) services are increasingly provided by
        mobile service providers as numerous devices, home appliances,
        utility meters, cars, video surveillance cameras, and health
        monitors are connected with mobile broadband
        technologies. Different applications, e.g., in a home
        appliance or in-car network, use Bluetooth, Wi-Fi, or ZigBee
        locally and connect to a cellular module acting as a gateway
        between the constrained environment and the mobile cellular
        network.
      </t>
      <t>
        Such a gateway might provide different options for the
        connectivity of mobile networks and constrained devices:
        <list style="symbols">
          <t>
            a smartphone with 3G/4G and WLAN radio might use BT-LE to
            connect to the devices in a home area network,
          </t>
          <t>
            a femtocell might be combined with home gateway
            functionality acting as a low-power cellular base station
            connecting smart devices to the application server of a
            mobile service provider,
          </t>
          <t>
            an embedded cellular module with LTE radio connecting the
            devices in the car network with the server running the
            telematics service,
          </t>
          <t>
            an M2M gateway connected to the mobile operator network
            supporting diverse Internet of Things (IoT) connectivity technologies including
            ZigBee and Constrained Application Protocol (CoAP) over 6LoWPAN over IEEE 802.15.4.
          </t>
        </list>
      </t>
      <t>
        Common to all scenarios above is that they are embedded in a
        service and connected to a network provided by a mobile
        service provider. Usually, there is a hierarchical deployment
        and management topology in place where different parts of the
        network are managed by different management entities and the
        count of devices to manage is high (e.g., many thousands).  In
        general, the network is comprised of manifold types and sizes of
        devices matching to different device classes.  As such, the
        managing entity needs to be prepared to manage devices with
        diverse capabilities using different communication or
        management protocols.  In the case in which the devices are directly
        connected to a gateway, they most likely are managed by a
        management entity integrated with the gateway, which itself is
        part of the NMS run by the mobile
        operator.  Smartphones or embedded modules connected to a
        gateway might themselves be in charge of managing the devices on
        their level.  The initial and subsequent configuration of such
        a device is mainly based on self-configuration and is
        triggered by the device itself.
      </t>
      <t>
        The gateway might be in charge of filtering and aggregating
        the data received from the device as the information sent by
        the device might be mostly redundant.
      </t>
    </section>
  </section> <!-- Access Technologies -->

 <section anchor="lifecycle" title="Device Life Cycle">
   <t>
     Since constrained devices deployed in a network might go through
     multiple phases in their lifetime, it is possible for different
     managers of networks and/or devices to exist during different
     parts of the device lifetimes. An in-depth discussion regarding
     the possible device life cycles can be found in <xref
     target="IOT-SEC"/>.
   </t>
   <section title="Manufacturing and Initial Testing">
     <t>
       Typically, the life cycle of a device begins at the
       manufacturing stage. During this phase, the manufacturer of the
       device is responsible for the management and configuration of
       the devices. It is also possible that a certain use case might
       utilize multiple types of constrained devices (e.g.,
       temperature sensors, lighting controllers, etc.) and these
       could be manufactured by different entities. As such, during
       the manufacturing stage, different managers can exist for
       different devices. Similarly, during the initial testing phase,
       where device quality-assurance tasks might be performed, the
       manufacturer remains responsible for the management of devices
       and networks that might comprise them.
     </t>
   </section>
   <section title="Installation and Configuration">
     <t>
       The responsibility of managing the devices must be transferred
       to the installer during the installation phase. There must
       exist procedures for transferring management responsibility
       between the manufacturer and installer. The installer may be
       the customer or an intermediary contracted to set up the devices
       and their networks. It is important that the NMS that is utilized
       allows devices originating at different vendors to be managed,
       ensuring interoperability between them and the configuration of
       trust relationships between them as well.
     </t>
     <t>
       It is possible that the installation and configuration
       responsibilities might lie with different entities. For
       example, the installer of a device might only be responsible
       for cabling a network, physically installing the devices, and
       ensuring initial network connectivity between them (e.g.,
       configuring IP addresses). Following such an installation, the
       customer or a subcontractor might actually configure the
       operation of the device. As such, during installation and
       configuration multiple parties might be responsible for
       managing a device and appropriate methods must be available to
       ensure that this management responsibility is transferred
       suitably.
     </t>
   </section>
   <section title="Operation and Maintenance">
     <t>
       At the outset of the operation phase, the operational
       responsibility of a device and network should be passed on to
       the customer. It is possible that the customer, however, might
       contract the maintenance of the devices and network to a
       subcontractor. In this case, the NMS and management protocol
       should allow for configuring different levels of access to the
       devices. Since different maintenance vendors might be used for
       devices that perform different functions (e.g., HVAC, lighting,
       etc.), it should also be possible to restrict management access
       to devices based on the currently responsible manager.
     </t>
   </section>
   <section title="Recommissioning and Decommissioning">
     <t>
       The owner of a device might choose to replace, repurpose, or
       even decommission it. In each of these cases, either the
       customer or the contracted maintenance agency must ensure that
       appropriate steps are taken to meet the end goal.
     </t>
     <t>
       In case the devices needs to be replaced, the manager of the
       network (customer or contractor responsible) must detach the
       device from the network, remove all appropriate configuration,
       and discard the device. A new device must then be configured to
       replace it. The NMS should allow for the transferring of the configuration
       and replacing an existing device. The management
       responsibility of the operation/maintenance manager would end
       once the device is removed from the network. During the
       installation of the new replacement device, the same
       responsibilities would apply as those during the Installation
       and Configuration phases.
     </t>
     <t>
       The device being replaced may not have yet reached end-of-life,
       and as such, instead of being discarded, it may be installed in
       a new location. In this case, the management responsibilities
       are once again resting in the hands of the entities responsible
       for the Installation and Configuration phases at the new
       location.
     </t>
     <t>
       If a device is repurposed, then it is possible that the
       management responsibility for this device changes as well. For
       example, a device might be moved from one building to
       another. In this case, the managers responsible for devices and
       networks in each building could be different. As such, the NMS
       must not only allow for changing configuration but also
       the transferring of management responsibilities.
     </t>
     <t>
       In case a device is decommissioned, the management
       responsibility typically ends at that point.
     </t>
   </section>
 </section>
   
 <section anchor="usecase" title="Use Cases">

  <section anchor="use_env_mon" title="Environmental Monitoring">
    <t>
      Environmental monitoring applications are characterized by the
      deployment of a number of sensors to monitor emissions, water
      quality, or even the movements and habits of wildlife. Other
      applications in this category include earthquake or tsunami
      early-warning systems. The sensors often span a large geographic
      area; they can be mobile; and they are often difficult to
      replace. Furthermore, the sensors are usually not protected
      against tampering.
    </t>
    <t>
      Management of environmental-monitoring applications is largely
      concerned with monitoring whether the system is still
      functional and the roll out of new constrained devices in case
      the system loses too much of its structure. The constrained
      devices themselves need to be able to establish connectivity
      (autoconfiguration), and they need to be able to deal with
      events such as losing neighbors or being moved to other
      locations.
    </t>

    <t>
      Management responsibility typically rests with the organization
      running the environmental-monitoring application. Since these
      monitoring applications must be designed to tolerate a number of
      failures, the time scale for detecting and recording failures is,
      for some of these applications, likely measured in hours and
      repairs might easily take days. In fact, in some scenarios it
      might be more cost- and time-effective not to repair such
      devices at all. However, for certain environmental monitoring
      applications, much tighter time scales may exist and might be
      enforced by regulations (e.g., monitoring of nuclear radiation).
    </t>
    <t>
      Since many applications of environmental-monitoring sensors are
      likely to be in areas that are important to safety (flood
      monitoring, nuclear radiation monitoring, etc.), it is important
      for management protocols and NMSs to
      ensure appropriate security protections. These protections
      include not only access control, integrity, and availability of
      data, but also provide appropriate mechanisms that can deal with
      situations that might be categorized as emergencies or when
      tampering with sensors/data might be detected.
    </t>
  </section>

  <section anchor="use_infra-mon" title="Infrastructure Monitoring">
    <t>
      Infrastructure monitoring is concerned with the monitoring of
      infrastructures such as bridges, railway tracks, or (offshore)
      windmills. The primary goal is usually to detect any events or
      changes of the structural conditions that can impact the risk
      and safety of the infrastructure being monitored. Another
      secondary goal is to schedule repair and maintenance activities
      in a cost-effective manner.
    </t>
    <t>
      The infrastructure to monitor might be in a factory or spread
      over a wider area (but difficult to access). As such, the network
      in use might be based on a combination of fixed and wireless
      technologies, which use robust networking equipment and support
      reliable communication via application-layer transactions. It is
      likely that constrained devices in such a network are mainly C2
      devices <xref target="RFC7228"/> and have to be controlled
      centrally by an application running on a server. In case such a
      distributed network is widely spread, the wireless devices might
      use diverse long-distance wireless technologies such as Worldwide Interoperability for Microwave Access (WiMAX)
      or 3G/LTE. In cases, where an in-building network is involved,
      the network can be based on Ethernet or wireless technologies
      suitable for in-building use.
    </t>
    <t>
      The management of infrastructure monitoring applications is
      primarily concerned with the monitoring of the functioning of
      the system. Infrastructure monitoring devices are typically
      rolled out and installed by dedicated experts, and updates are
      rare since the infrastructure itself does not change often. However,
      monitoring devices are often deployed in unsupervised
      environments; hence, special attention must be given to
      protecting the devices from being modified.
    </t>
    <t>
      Management responsibility typically rests with the organization
      owning the infrastructure or responsible for its operation. The
      time scale for detecting and recording failures is likely
      measured in hours and repairs might easily take days. However,
      certain events (e.g., natural disasters) may require that status
      information be obtained much more quickly and that replacements
      of failed sensors can be rolled out quickly (or redundant
      sensors are activated quickly). In case the devices are
      difficult to access, a self-healing feature on the device might
      become necessary. Since infrastructure monitoring is closely
      related to ensuring safety, management protocols and systems
      must provide appropriate security protections to ensure
      confidentiality, integrity, and availability of data.
    </t>
  </section>
  
  <section anchor="use_ind_app" title="Industrial Applications">
    <t>
      Industrial Applications and smart manufacturing refer to tasks
      such as networked control and monitoring of manufacturing
      equipment, asset and situation management, or manufacturing
      process control.  For the management of a factory, it is becoming
      essential to implement smart capabilities.  From an engineering
      standpoint, industrial applications are intelligent systems
      enabling rapid manufacturing of new products, dynamic response
      to product demands, and real-time optimization of manufacturing
      production and supply-chain networks.  Potential industrial
      applications (e.g., for smart factories and smart manufacturing)
      are:
      <list style="symbols">      
        <t> 
          Digital control systems with embedded, automated process
          controls; operator tools; and service information
          systems optimizing plant operations and safety.
        </t>
        <t>
          Asset management using predictive maintenance tools,
          statistical evaluation, and measurements maximizing plant
          reliability.
        </t>
        <t>
          Smart sensors detecting anomalies to avoid abnormal or
          catastrophic events.
        </t>
        <t>
          Smart systems integrated within the industrial energy-management system and externally with the smart grid
          enabling real-time energy optimization.
        </t>
      </list>
    </t>
    <t>
      Management of Industrial Applications and smart manufacturing
      may, in some situations, involve Building Automation tasks such as
      control of energy, HVAC, lighting, or access control. Interacting with
      management systems from other application areas might be
      important in some cases (e.g., environmental monitoring for
      electric energy production, energy management for dynamically
      scaling manufacturing, vehicular networks for mobile asset
      tracking). Management of constrained devices and networks may
      not only refer to the management of their network
      connectivity. Since the capabilities of constrained devices are
      limited, it is quite possible that a management system would
      even be required to configure, monitor, and operate the primary
      functions for which a constrained device is utilized, besides
      managing its network connectivity.
    </t>
    <t>
      Sensor networks are an essential technology used for smart
      manufacturing. Measurements, automated controls, plant
      optimization, health and safety management, and other functions
      are provided by a large number of networked sectors. Data
      interoperability and seamless exchange of product, process, and
      project data are enabled through interoperable data systems used
      by collaborating divisions or business systems. Intelligent
      automation and learning systems are vital to smart manufacturing,
      but they must be effectively integrated with the decision
      environment. The NMS utilized must ensure timely delivery of
      sensor data to the control unit so it may take appropriate
      decisions. Similarly, the relaying of commands must also be
      monitored and managed to ensure optimal functioning. Wireless
      sensor networks (WSNs) have been developed for machinery
      Condition-based Maintenance (CBM) as they offer significant cost
      savings and enable new functionalities. Inaccessible locations,
      rotating machinery, hazardous areas, and mobile assets can be
      reached with wireless sensors. Today, WSNs can provide wireless
      link reliability, real-time capabilities, and quality-of-service
      and they can enable industrial and related wireless sense and control
      applications.
    </t>
    <t>
      Management of industrial and factory applications is largely
      focused on monitoring whether the system is still functional,
      real-time continuous performance monitoring, and optimization as
      necessary. The factory network might be part of a campus network
      or connected to the Internet. The constrained devices in such a
      network need to be able to establish configuration themselves
      (autoconfiguration) and might need to deal with error
      conditions as much as possible locally. Access control has to be
      provided with multi-level administrative access and
      security. Support and diagnostics can be provided through remote
      monitoring access centralized outside of the factory.
    </t>
    <t>
      Factory-automation tasks require that continuous monitoring be
      used to optimize production. Groups of manufacturing and
      monitoring devices could be defined to establish relationships
      between them. To ensure timely optimization of processes,
      commands from the NMS must arrive at all destination within an
      appropriate duration. This duration could change based on the
      manufacturing task being performed. Installation and operation
      of factory networks have different requirements. During the
      installation phase, many networks, usually distributed along
      different parts of the factory/assembly line, coexist without a
      connection to a common backbone. A specialized installation tool
      is typically used to configure the functions of different types
      of devices, in different factory locations, in a secure
      manner. At the end of the installation phase, interoperability
      between these stand-alone networks and devices must be
      enabled. During the operation phase, these stand-alone networks
      are connected to a common backbone so that they may retrieve
      control information from and send commands to appropriate
      devices.
    </t>
    <t>
      Management responsibility is typically owned by the organization
      running the industrial application. Since the monitoring
      applications must handle a potentially large number of failures,
      the time scale for detecting and recording failures is, for some
      of these applications, likely measured in minutes. However, for
      certain industrial applications, much tighter time scales may
      exist, e.g., in real-time, which might be enforced by the
      manufacturing process or the use of critical
      material. Management protocols and NMSs must ensure appropriate
      access control since different users of industrial control
      systems will have varying levels of permissions. For example, while
      supervisors might be allowed to change production parameters,
      they should not be allowed to modify the functional
      configuration of devices like a technician should. It is also
      important to ensure integrity and availability of data since
      malfunctions can potentially become safety issues. This also
      implies that management systems must be able to react to
      situations that may pose dangers to worker safety.
    </t>
  </section>


  <section anchor="use_energy" title="Energy Management">
    <t>
      The EMAN working group developed an energy-management framework
      <xref target="RFC7326"/> for devices and device components
      within or connected to communication networks.  This document
      observes that one of the challenges of energy management is that
      a power distribution network is responsible for the supply of
      energy to various devices and components, while a separate
      communication network is typically used to monitor and control
      the power distribution network.  Devices in the context of
      energy management can be monitored for parameters like power,
      energy, demand and power quality.  If a device contains
      batteries, they can be also monitored and managed.
    </t>
    <t>
      Energy devices differ in complexity and may include basic
      sensors or switches, specialized electrical meters, or power
      distribution units (PDU), and subsystems inside the network
      devices (routers, network switches) or home or industrial
      appliances.  The operators of an energy-management system are
      either the utility providers or customers that aim to control
      and reduce the energy consumption and the associated costs.  The
      topology in use differs and the deployment can cover areas from
      small surfaces (individual homes) to large geographical areas.
      The EMAN requirements document <xref target="RFC6988"/>
      discusses the requirements for energy management concerning
      monitoring and control functions.
    </t> 
    <t> 
      It is assumed that energy management will apply to a large range
      of devices of all classes and networks topologies.  Specific
      resource monitoring, like battery utilization and availability,
      may be specific to devices with lower physical resources (device
      classes C0 or C1 <xref target="RFC7228"/>).
    </t> 
    <t>
      Energy management is especially relevant to the Smart Grid.  A
      Smart Grid is an electrical grid that uses data networks to
      gather and act on energy and power-related information in an
      automated fashion with the goal to improve the efficiency,
      reliability, economics, and sustainability of the production and
      distribution of electricity.
    </t>
    <t>
      Smart Metering is a good example of an energy-management application based on Smart Grid.  Different types of possibly wireless
      small meters all together produce a large amount of data, which
      is collected by a central entity and processed by an application
      server, which may be located within the customer's residence or
      off site in a data center.  The communication infrastructure can
      be provided by a mobile network operator as the meters in urban
      areas will most likely have a cellular or WiMAX radio.  In case
      the application server is located within the residence, such
      meters are more likely to use Wi&nbhy;Fi protocols to interconnect
      with an existing network.
    </t>
    <t>
      An Advanced Metering Infrastructure (AMI) network is another
      example of the Smart Grid that enables an electric utility to
      retrieve frequent electric usage data from each electric meter
      installed at a customer's home or business.  Unlike Smart
      Metering, in which case the customer or their agents install
      appliance-level meters, an AMI is typically
      managed by the utility providers and could also include other
      distribution automation devices like transformers and
      reclosers. Meters in AMI networks typically contain constrained
      devices that connect to mesh networks with a low-bandwidth
      radio. Usage data and outage notifications can be sent by these
      meters to the utility's headend systems, via aggregation points
      of higher-end router devices that bridge the constrained network
      to a less constrained network via cellular, WiMAX, or
      Ethernet. Unlike meters, these higher-end devices might be
      installed on utility poles owned and operated by a separate
      entity.
    </t>
    <t>
      It thereby becomes important for a management application not
      only to be able to work with diverse types of devices, but also
      to work over multiple links that might be operated and managed by
      separate entities, each having divergent policies for their own
      devices and network segments. During management operations, like
      firmware updates, it is important that the management systems
      perform robustly in order to avoid accidental outages of
      critical power systems that could be part of AMI networks. In
      fact, since AMI networks must also report on outages, the
      management system might have to manage the energy properties of
      battery-operated AMI devices themselves as well.
    </t>
    <t>
      A management system for home-based Smart Metering solutions is
      likely to have devices laid out in a simple topology. However,
      AMI network installations could have thousands of nodes per
      router, i.e., higher-end device, which organize themselves in an
      ad hoc manner. As such, a management system for AMI networks
      will need to discover and operate over complex topologies as
      well. In some situations, it is possible that the management
      system might also have to set up and manage the topology of
      nodes, especially critical routers.  Encryption-key management
      and sharing in both types of networks are also likely to be
      important for providing confidentiality for all data traffic.
      In AMI networks, the key may be obtained by a meter only after an
      end-to-end authentication process based on certificates. The Smart
      Metering solution could adopt a similar approach or the security
      may be implied due to the encrypted Wi-Fi networks they become
      part of.
    </t>
    <t>
      The management of such a network requires end-to-end management
      of and information exchange through different types of networks.
      However, as of today, there is no integrated energy-management
      approach and no common information model available.  Specific
      energy-management applications or network islands use their own
      management mechanisms.
    </t>
</section>
   
  <section anchor="use_med_app" title="Medical Applications">
    <t>
      Constrained devices can be seen as an enabling technology for
      advanced and possibly remote health-monitoring and emergency-notification systems, ranging from monitors for blood pressure and heart rate
      to advanced devices capable of monitoring implanted
      technologies, such as pacemakers or advanced hearing
      aids. Medical sensors may not only be attached to human bodies,
      they might also exist in the infrastructure used by humans such
      as bathrooms or kitchens. Medical applications will also be used
      to ensure treatments are being applied properly, and they might
      guide people losing orientation. Fitness and wellness
      applications, such as connected scales or wearable heart
      monitors, encourage consumers to exercise and empower
      self-monitoring of key fitness indicators. Different
      applications use Bluetooth, Wi-Fi, or ZigBee connections to
      access the patient's smartphone or home cellular connection to
      access the Internet.
    </t>
    <t>
      Constrained devices that are part of medical applications are
      managed either by the users of those devices or by an
      organization providing medical (monitoring) services for
      physicians. In the first case, management must be automatic
      and/or easy to install and set up by laypeople. In the
      second case, it can be expected that devices will be controlled by
      specially trained people.     In both cases, however,
  it is crucial to protect the safety and privacy of the people who use medical devices. Security precautions to protect access
      (authentication, encryption, integrity protections, etc.) to
      such devices may be critical to safeguarding the individual. The
      level of access granted to different users also may need to be
      regulated. For example, an authorized surgeon or doctor must be
      allowed to configure all necessary options on the devices;
      however, a nurse or technician may only be allowed to retrieve
      data that can assist in diagnosis. Even though the data
      collected by a heart monitor might be protected, the pure
      fact that someone carries such a device may need protection. As
      such, certain medical appliances may not want to participate in
      discovery and self-configuration protocols in order to remain
      invisible.
    </t>
    <t>
  Many medical devices are likely to be used (and relied upon) to
  provide data to physicians in critical situations in which the
  patient might not be able to report such data themselves.
  Timely
      delivery of data can be quite important in certain applications
      like patient-mobility monitoring in nursing homes. Data must
      reach the physician and/or emergency services within specified
      limits of time in order to be useful. As such, fault detection
      of the communication network or the constrained devices becomes
      a crucial function of the management system that must be carried
      out with high reliability and, depending on the medical
      appliance and its application, within seconds.
    </t>
  </section>
    
  <section anchor="use_build_aut" title="Building Automation">
    <t>
      Building automation comprises the distributed systems designed
      and deployed to monitor and control the mechanical, electrical,
      and electronic systems inside buildings with various
      destinations (e.g., public and private, industrial,
      institutions, or residential). Advanced Building Automation
      Systems (BASs) may be deployed concentrating the various
      functions of safety, environmental control, occupancy,
      and security. Increasingly, the deployment of the various functional
      systems is connected to the same communication infrastructure
      (possibly IP-based), which may involve wired or
      wireless communication networks inside the building. 
    </t>
    <t>
      Building automation requires the deployment of a large number
      (10 to 100,000) of sensors that monitor the status of devices,
      parameters inside the building, and controllers with different
      specialized functionality for areas within the building or the
      totality of the building. Inter-node distances between
      neighboring nodes vary from 1 to 20 meters.  The NMS must, as
      a result, be able to manage and monitor a large number of
      devices, which may be organized in multi-hop meshed
      networks. Distances between the nodes, and the use of
      constrained protocols, means that networks of nodes might be
      segmented. The management of such network segments and nodes in
      these segments should be possible. Contrary to home automation,
      in building management the devices are expected to be managed
      assets and known to a set of commissioning tools and a data
      storage, such that every connected device has a known
      origin. This requires the management system to be able to
      discover devices on the network and ensure that the expected
      list of devices is currently matched. Management here includes
      verifying the presence of the expected devices and detecting the
      presence of unwanted devices.
    </t>
    <t>
      Examples of functions performed by controllers in building
      automation are regulating the quality, humidity, and temperature
      of the air inside the building as well as regulating the lighting. Other systems may
      report the status of the machinery inside the building like
      elevators or inside the rooms like projectors in meeting
      rooms. Security cameras and sensors may be deployed and operated
      on separate dedicated infrastructures connected to the common
      backbone. The deployment area of a BAS is typically inside one
      building (or part of it) or several buildings geographically
      grouped in a campus. A building network can be composed of
      network segments, where a network segment covers a floor, an
      area on the floor, or a given functionality (e.g., security
      cameras). It is possible that the management tasks of different
      types of some devices might be separated from others (e.g,
      security cameras might operate and be managed via a network separate
      from that of the HVAC in a building).
    </t>
    <t>
      Some of the sensors in BASs (for example,
      fire alarms or security systems) register, record, and transfer
      critical alarm information; therefore, they must be resilient to
      events like loss of power or security attacks. A management
      system must be able to deal with unintentional segmentation of
      networks due to power loss or channel unavailability. It must
      also be able to detect security events. Due to specific
      operating conditions required from certain devices, there might
      be a need to certify components and subsystems operating in such
      constrained conditions based on specific requirements. Also, in
      some environments, the malfunctioning of a control system (like
      temperature control) needs to be reported in the shortest
      possible time. Complex control systems can misbehave, and their
      critical status reporting and safety algorithms need to be basic
      and robust and perform even in critical conditions. Providing
      this monitoring, configuration and notification service is an
      important task of the management system used in building
      automation.
    </t>    
    <t>
      In some cases, building automation solutions are deployed in
      newly designed buildings; in other cases, it might be over
      existing infrastructures. In the first case, there is a broader
      range of possible solutions, which can be planned for the
      infrastructure of the building. In the second case, the solution
      needs to be deployed over an existing infrastructure taking into
      account factors like existing wiring, distance limitations, and the
      propagation of radio signals over walls and floors, thereby
      making deployment difficult. As a result, some of the existing
      WLAN solutions (e.g., <xref target="IEEE802.11" /> or <xref target="IEEE802.15" />) may be
      deployed. In mission-critical or security-sensitive environments
      and in cases where link failures happen often, topologies that
      allow for reconfiguration of the network and connection
      continuity may be required. Some of the sensors deployed in
      building automation may be very simple constrained devices for
      which C0 or C1 <xref target="RFC7228"/> may be assumed. 
    </t>    
    <t>
      For lighting applications, groups of lights must be defined and
      managed. Commands to a group of light must arrive within 200 ms
      at all destinations. The installation and operation of a
      building network has different requirements. During the
      installation, many stand-alone networks of a few to 100 nodes
      coexist without a connection to the backbone. During this
      phase, the nodes are identified with a network identifier
      related to their physical location. Devices are accessed from an
      installation tool to connect them to the network in a secure
      fashion. During installation, the setting of parameters of
      common values to enable interoperability may be required. During
      operation, the networks are connected to the backbone while
      maintaining the network identifier to physical location
      relation. Network parameters like address and name are stored in
      the DNS. The names can assist in determining the physical location
      of the device.
    </t>
    <t>
      It is also important for a building automation NMS to take
      safety and security into account. Ensuring privacy and
      confidentiality of data, such that unauthorized parties do not
      get access to it, is likely to be important since users'
      individual behaviors could be potentially understood via their
      settings. Appropriate security considerations for authorization
      and access control to the NMS is also important since different
      users are likely to have varied levels of operational
      permissions in the system. For example, while end users should be able
      to control lighting systems, HVAC systems, etc., only qualified
      technicians should be able to configure parameters that change
      the fundamental operation of a device. It is also important for
      devices and the NMS to be able to detect and report any
      tampering they might find, since these could lead to potential
      user safety concerns, e.g., if sensors controlling air quality
      are tampered with such that the levels of carbon monoxide become
      life threatening. This implies that an NMS should also be able to
      deal with and appropriately prioritize situations that might
      potentially lead to safety concerns.
    </t>
  </section>

  <section anchor="use_home_aut" title="Home Automation">
    <t>
      Home automation includes the control of lighting, heating,
      ventilation, air conditioning, appliances, entertainment and
      home security devices to improve convenience, comfort, energy
      efficiency, and safety. It can be seen as a residential
      extension of building automation. However, unlike a BAS, the infrastructure in a home is operated in a
      considerably more ad hoc manner. While in some installations it
      is likely that there is no centralized management system akin
      to a BAS available, in other
      situations outsourced and cloud-based systems responsible for
      managing devices in the home might be used.
    </t>
    <t>
      Home-automation networks need a certain amount of configuration
      (associating switches or sensors to actuators) that is either
      provided by electricians deploying home-automation solutions, by
      third-party home-automation service providers (e.g., small
      specialized companies or home-automation device manufacturers)
      or by residents by using the application user interface provided
      by home-automation devices to configure (parts of) the home-automation solution. Similarly, failures may be reported via
      suitable interfaces to residents or they might be recorded and
      made available to services providers in charge of the
      maintenance of the home-automation infrastructure.
    </t>
    <t>
      The management responsibility either lies with the residents or
      is outsourced to electricians and/or third parties
      providing management of home-automation solutions as a
      service. A varying combination of electricians, service
      providers, or the residents may be responsible for different
      aspects of managing the infrastructure.  The time scale for
      failure detection and resolution is, in many cases, likely counted
      in hours to days.
    </t>
  </section>

 
  <section anchor="use_trpt_app" title="Transport Applications">
    <t>
      "Transport application" is a generic term for the integrated
      application of communications, control, and information
      processing in a transportation system.  "Transport telematics" and
      "vehicle telematics" are both used as terms for the group of
      technologies that support transportation systems.  Transport
      applications running on such a transportation system cover all
      modes of the transport and consider all elements of the
      transportation system, i.e. the vehicle, the infrastructure, and
      the driver or user, interacting together dynamically.  Examples
      for transport applications are inter- and intra-vehicular
      communication, smart traffic control, smart parking, electronic
      toll-collection systems, logistic and fleet management, vehicle
      control, and safety and roadside assistance.
    </t>
    <t>
      As a distributed system, transport applications require an
      end-to-end management of different types of networks.  It is
      likely that constrained devices in a network (e.g., a moving
      in-car network) have to be controlled by an application running
      on an application server in the network of a service provider.
      Such a highly distributed network including cellular devices on
      vehicles is assumed to include a wireless access network using
      diverse long-distance wireless technologies such as WiMAX,
      3G/LTE, or satellite communication, e.g., based on an embedded
      hardware module.  As a result, the management of constrained
      devices in the transport system might be necessary to plan
      top-down and might need to use data models obliged from and
      defined on the application layer.  The assumed device classes in
      use are mainly C2 <xref target="RFC7228"/> devices.  In cases,
      where an in-vehicle network is involved, C1 devices <xref
      target="RFC7228"/> with limited capabilities and a
      short-distance constrained radio network, e.g., IEEE 802.15.4
      might be used additionally.
    </t>

    <t>
      All Transport Applications will require an IT infrastructure to
      run on top of, e.g., in public-transport scenarios like trains,
      buses, or metro networks infrastructure might be provided,
      maintained, and operated by third parties like mobile-network or
      satellite-network operators.  However, the management
      responsibility of the transport application typically rests
      within the organization running the transport application (in
      the public-transport scenario, this would typically be the
      public-transport operator). Different aspects of the
      infrastructure might also be managed by different entities. For example, the in-car devices are likely to be installed and managed by the
manufacturer, while the local government or transportation authority might be
responsible for the on-road vehicular communication infrastructure used by
these devices. The backend
      infrastructure is also likely to be maintained by third-party
      operators. As such, the NMS must be able to deal with different
      network segments (each being operated and controlled by separate
      entities) and enable appropriate access control and security.
    </t>
    <t>
      Depending on the type of application domain (vehicular or
      stationary) and service being provided, it is important
      for the NMS to be able to function with different architectures,
      since different manufacturers might have their own proprietary
      systems relying on a specific management topology option, as
      described in <xref target="RFC7547"/>. Moreover, constituents of
      the network can either be private, belong to individuals or
      private companies, or be owned by public institutions leading to
      different legal and organization requirements. Across the entire
      infrastructure, a variety of constrained devices is likely to
      be used, and they must be individually managed. The NMS must be able
      to either work directly with different types of devices or have
      the ability to interoperate with multiple different systems.
    </t>
    <t>
      The challenges in the management of vehicles in a mobile-transport application are manifold. The up-to-date position of
      each node in the network should be reported to the corresponding
      management entities, since the nodes could be moving within or
      roaming between different networks.  Secondly, a variety of
      troubleshooting information, including sensitive location
      information, needs to be reported to the management system in
      order to provide accurate service to the customer. Management
      systems dealing with mobile nodes could possibly exploit
      specific patterns in the mobility of the nodes. These patterns
      emerge due to repetitive vehicular usage in scenarios like
      people commuting to work and supply vehicles transporting
      shipments between warehouses, etc. The NMS must also be able
      to handle partitioned networks, which would arise due to the
      dynamic nature of traffic resulting in large inter-vehicle gaps
      in sparsely populated scenarios. Since mobile nodes might roam
      in remote networks, the NMS should be able to provide operating
      configuration updates regardless of node location.
    </t>
    <t>
      The constrained devices in a moving transport network might be
      initially configured in a factory, and a reconfiguration might be
      needed only rarely.  New devices might be integrated in an
      ad hoc manner based on self-management and self-configuration
      capabilities.  Monitoring and data exchange might be necessary
      via a gateway entity connected to the backend transport
      infrastructure.  The devices and entities in the transport
      infrastructure need to be monitored more frequently and may be
      able to communicate with a higher data rate.  The connectivity
      of such entities does not necessarily need to be wireless.  The
      time scale for detecting and recording failures in a moving
      transport network is likely measured in hours, and repairs might
      easily take days.  It is likely that a self-healing feature
      would be used locally. On the other hand, failures in fixed
      transport-application infrastructure (e.g., traffic lights,
      digital-signage displays) are likely to be measured in minutes so
      as to avoid untoward traffic incidents. As such, the NMS must be
      able to deal with differing timeliness requirements based on the
      type of devices.
    </t>
    <t>
      Since transport applications of the constrained devices and
      networks deal with automotive vehicles, malfunctions and misuse
      can potentially lead to safety concerns as well. As such,
      besides access control, privacy of user data, and timeliness,
      management systems should also be able to detect situations that
      are potentially hazardous to safety. Some of these situations
      could be automatically mitigated, e.g., traffic lights with
      incorrect timing, but others might require human intervention,
      e.g., failed traffic lights. The management system should take
      appropriate actions in these situations. Maintaining data
      confidentiality and integrity is also an important security
      aspect of a management system since tampering (or malfunction)
      can also lead to potentially dangerous situations.
    </t>
  </section>

  <section anchor="use_comm-net" title="Community Network Applications">
    <t>
      Community networks are comprised of constrained routers in a
      multi-hop mesh topology, communicating over lossy, and often
      wireless, channels. While the routers are mostly non-mobile, the
      topology may be very dynamic because of fluctuations in link
      quality of the (wireless) channel caused by, e.g., obstacles, or
      other nearby radio transmissions. Depending on the routers that
      are used in the community network, the resources of the routers
      (memory, CPU) may be more or less constrained -- available
      resources may range from only a few kilobytes of RAM to several
      megabytes or more, and CPUs may be small and embedded, or more
      powerful general-purpose processors. Examples of such community
      networks are the FunkFeuer network (Vienna, Austria), FreiFunk
      (Berlin, Germany), Seattle Wireless (Seattle, USA), and AWMN
      (Athens, Greece). These community networks are public and
      non-regulated, allowing their users to connect to each other and
      -- through an uplink to an ISP -- to the Internet. No fee, other
      than the initial purchase of a wireless router, is charged for
      these services. Applications of these community networks can be
      diverse, e.g., location-based services, free Internet access,
      file sharing between users, distributed chat services, social
      networking, video sharing, etc.
    </t>
    <t>
      As an example of a community network, the FunkFeuer network
      comprises several hundred routers, many of which have several
      radio interfaces (with omnidirectional and some directed
      antennas). The routers of the network are small-sized wireless
      routers, such as the Linksys WRT54GL, available in 2011 for less
      than 50 euros. Each router, with 16 MB of RAM and 264 MHz of
      CPU power, is mounted on the rooftop of a user. When a new
      user wants to connect to the network, they acquire a wireless
      router, install the appropriate firmware and routing protocol,
      and mount the router on the rooftop. IP addresses for the router
      are assigned manually from a list of addresses (because of the
      lack of autoconfiguration standards for mesh networks in the
      IETF).
    </t>
    <t>
      While the routers are non-mobile, fluctuations in link quality
      require an ad hoc routing protocol that allows for quick
      convergence to reflect the effective topology of the network
      (such as Neighborhood Discovery Protocol (NHDP) <xref target="RFC6130"/> and Optimized Link State Routing version 2 (OLSRv2)
      <xref target="RFC7181"/> developed in the MANET WG). Usually, no
      human interaction is required for these protocols, as all
      variable parameters required by the routing protocol are either
      negotiated in the control traffic exchange or are only of local
      importance to each router (i.e. do not influence
      interoperability). However, external management and monitoring
      of an ad hoc routing protocol may be desirable to optimize
      parameters of the routing protocol. Such an optimization may
      lead to a topology that is perceived to be more stable and to a lower control
      traffic overhead (and therefore to a higher delivery success
      ratio of data packets, a lower end-to-end delay, and less
      unnecessary bandwidth and energy use).
    </t>

    <t>
      Different use cases for the management of community networks are
      possible:
      <list style="symbols">      


        <t>A single NMS, e.g., a border
          gateway providing connectivity to the Internet, requires
          managing or monitoring routers in the community network, in
          order to investigate problems (monitoring) or to improve
          performance by changing parameters (managing). As the
          topology of the network is dynamic, constant connectivity of
          each router towards the management station cannot be
          guaranteed. Current network management protocols, such as
          SNMP and Network Configuration Protocol (NETCONF), may be used (e.g., use of interfaces such
          as the NHDP-MIB <xref target="RFC6779"/>). However, when
          routers in the community network are constrained, existing
          protocols may require too many resources in terms of memory
          and CPU; and more importantly, the bandwidth requirements
          may exceed the available channel capacity in wireless mesh
          networks. Moreover, management and monitoring may be
          unfeasible if the connection between the NMS and the routers is frequently interrupted.
        </t>
        <t>
          Distributed network monitoring, in which more than one
          management station monitors or manages other
          routers. Because connectivity to a server cannot be
          guaranteed at all times, a distributed approach may provide
          a higher reliability, at the cost of increased
          complexity. Currently, no IETF standard exists for
          distributed monitoring and management.
        </t>
        <t>
          Monitoring and management of a whole network or a group of
          routers. Monitoring the performance of a community network
          may require more information than what can be acquired from
          a single router using a network management
          protocol. Statistics, such as topology changes over time,
          data throughput along certain routing paths, congestion,
          etc., are of interest for a group of routers (or the routing
          domain) as a whole. As of 2014, no IETF standard allows for
          monitoring or managing whole networks instead of single
          routers.
        </t>
      </list>
    </t>
    
  </section>
  
  <section anchor="use_field" title="Field Operations">
    <t>
      The challenges of configuring and monitoring networks
      operated in the field by rescue and security agencies can be
      different from the other use cases since the requirements and
      operating conditions of such networks are quite different.
    </t>
    <t>
      With technology advancements, field networks operated nowadays
      are becoming large and can consist of a variety of different
      types of equipment that run different protocols and tools that
      obviously increase complexity of these mission-critical
      networks.  In many scenarios, configurations are, most likely,
      manually performed.  Furthermore, some legacy and even modern
      devices do not even support IP networking.  A majority of
      protocols and tools developed by vendors that are being used are
      proprietary, which makes integration more difficult.
    </t>
    <t>
      The main reason for this disjoint operation scenario is that
      most equipment is developed with specific task requirements in
      mind, rather than interoperability of the varied equipment
      types.  For example, the operating conditions experienced by
      high altitude security equipment is significantly different from
      that used in desert conditions. Similarly, equipment used in fire rescue has different
      requirements than flood-relief equipment. Furthermore,
      interoperation of equipment with telecommunication equipment was
      not an expected outcome or (in some scenarios) may not even
      be desirable.
    </t>
    <t>
      Currently, field networks operate with a fixed Network
      Operations Center (NOC) that physically manages the
      configuration and evaluation of all field devices.  Once
      configured, the devices might be deployed in fixed or mobile
      scenarios.  Any configuration changes required would need to be
      appropriately encrypted and authenticated to prevent
      unauthorized access.
    </t>
    <t>
      Hierarchical management of devices is a common requirement in
      such scenarios since local managers or operators may need to
      respond to changing conditions within their purview.  The level
      of configuration management available at each hierarchy must
      also be closely governed.
    </t>
    <t>
      Since many field operation devices are used in hostile
      environments, a high failure and disconnection rate should be
      tolerated by the NMS, which must also be able to deal with
      multiple gateways and disjoint management protocols.
    </t>
    <t>
      Multi-national field operations involving search, rescue, and
      security are becoming increasingly common, requiring
      interoperation of a diverse set of equipment designed with
      different operating conditions in mind.  Furthermore, different
      intra- and inter-governmental agencies are likely to have a
      different set of standards, best practices, rules and
      regulations, and implementation approaches that may contradict or
      conflict with each other.  The NMS should be able to detect
      these and handle them in an acceptable manner, which may require
      human intervention.
    </t>
  </section> <!-- Field -->

  </section> <!-- Use Cases -->
 

  <section anchor="Security" title="Security Considerations">
    <t>
      This document discusses use cases for management of networks
      with constrained devices. The security considerations described
      throughout the companion document <xref target="RFC7547"/> apply
      here as well.
    </t>

  </section>
                  
</middle>

  <!--  ***** BACK MATTER ***** -->
<back>



<references title="Informative References">
  &rfc6130;
  &rfc6568;
  &rfc6779;
  &rfc6988;
  &rfc7181;
  &rfc7228;
  &rfc7326;

  <!-- draft-ietf-opsawg-coman-probstate-reqs: RFC 7547 -->
  <reference anchor="RFC7547" target="http://www.rfc-editor.org/info/rfc7547">
    <front>
      <title>
        Management of Networks with Constrained Devices: Problem
        Statement and Requirements
      </title>
      <author initials="M" surname="Ersue" fullname="Mehmet Ersue" role="editor">
        <organization/>
      </author>
      <author initials="D" surname="Romascanu" fullname="Dan
                                                         Romascanu">
        <organization/>
      </author>
      <author initials="J" surname="Schoenwaelder" fullname="Jurgen
        Schoenwaelder">
        <organization/>
      </author>
      <author initials="U" surname="Herberg" fullname="Ulrich Herberg">
         <organization/>
      </author>
      <date month="May" year="2015"/>
    </front>
    <seriesInfo name="RFC" value="7547"/>

  </reference>

<!--draft-garcia-core-security-06; Expired -->
  <reference anchor="IOT-SEC">
    <front>
      <title>
        Security Considerations in the IP-based Internet of Things
      </title>
      <author initials="O" surname="Garcia-Morchon" fullname="Oscar Garcia-Morchon">
        <organization/>
      </author>
      <author initials="S" surname="Kumar" fullname="Sandeep S. Kumar">
        <organization/>
      </author>
      <author initials="S" surname="Keoh" fullname="Sye Loong Keoh">
        <organization/>
      </author>
      <author initials="R" surname="Hummen" fullname="Rene Hummen">
        <organization/>
      </author>
      <author initials="R" surname="Struik" fullname="Rene Struik">
        <organization/>
      </author>
      <date month="September" day="11" year="2013"/>
    </front>
    <seriesInfo name="Work in Progress," value="draft-garcia-core-security-06"/>
  </reference>


<reference anchor="IEEE802.11" target="http://standards.ieee.org/about/get/802/802.11.html">
<front>
<title>Part 11: Wireless LAN Medium Access Control
(MAC) and Physical Layer (PHY) Specifications</title>
<author>
<organization>IEEE</organization>
</author>
<date month="March" year="2012" />
</front>
<seriesInfo name="IEEE" value="Standard 802.11" />

</reference>

      <reference anchor="IEEE802.15" target="https://standards.ieee.org/about/get/802/802.15.html">
        <front>
          <title>WIRELESS PERSONAL AREA NETWORKS (PANs)</title>

	  <author>
	    <organization>IEEE</organization>
	    </author>

          <date month="" year="2003-2014"/>
        </front>
  <seriesInfo name="IEEE" value="Standard 802.15" />
      </reference>


      <reference anchor="IEEE802.15.4" target="https://standards.ieee.org/about/get/802/802.15.html">
        <front>
          <title>Part 15.4: Low-Rate Wireless Personal Area Networks (LR-WPANs)</title>

	  <author>
	    <organization>IEEE</organization>
	    </author>

          <date month="September" year="2011"/>
        </front>
         <seriesInfo name="IEEE" value="Standard 802.15.4" />
      </reference>



</references>

  <section title="Acknowledgments" numbered="no">
    <t>
      The following persons reviewed and provided valuable comments during the creation of this document:
    </t>
    <t>
      Dominique Barthel, Carsten Bormann, Zhen Cao, Benoit Claise,
      Bert Greevenbosch, Ulrich Herberg, Ted Lemon, Kathleen Moriarty,
      James Nguyen, Zach Shelby, Peter van der Stok, and Martin
      Thomson.
    </t>

    <t>
      The authors would like to thank the reviewers and the
      participants on the Coman mailing list for their valuable
      contributions and comments.
    </t>

<t>Juergen Schoenwaelder and Anuj Sehgal were partly funded by Flamingo,
  a Network of Excellence project (ICT-318488) supported by the
  European Commission under its Seventh Framework Programme.</t>
 </section>

  <section title="Contributors" numbered="no">
    <t>
      Following persons made significant contributions to and reviewed
      this document:
      <list style="symbols">

      <t>Ulrich Herberg contributed <xref target="use_comm-net"/>, "Community Network Applications".</t>
      <t>Peter van der Stok contributed to <xref target="use_build_aut"/>, "Building Automation".</t>
      <t>Zhen Cao contributed to <xref target="access_mobile"/>, "Cellular Access Technologies".</t>
      <t>Gilman Tolle contributed <xref target="use_energy"/> "Energy Management".</t>
      <t>James Nguyen and Ulrich Herberg contributed to <xref
      target="use_field"/> "Field Operations".</t>

      </list>
    </t>
  </section>

</back>
</rfc>
