Routing Over Low power and Lossy networks (roll)

Last Modified: 2009-06-22

Additional information is available at tools.ietf.org/wg/roll

Chair(s):

  • JP Vasseur <jpv@cisco.com>

  • David Culler <culler@eecs.berkeley.edu>

    Routing Area Director(s):

  • Ross Callon <rcallon@juniper.net>
  • Adrian Farrel <adrian.farrel@huawei.com>

    Routing Area Advisor:

  • Adrian Farrel <adrian.farrel@huawei.com>

    Technical Advisor(s):

  • Rene Struik <rstruik@certicom.com>

    Mailing Lists:

    General Discussion: roll@ietf.org
    To Subscribe: http://www.ietf.org/mailman/listinfo/roll
    Archive: http://www.ietf.org/mail-archive/web/roll/

    Description of Working Group:

    Low power and Lossy networks (LLNs) are made up of many
    embedded devices with limited power, memory, and processing
    resources. They are interconnected by a variety of links, such as
    IEEE 802.15.4, Bluetooth, Low Power WiFi, wired or other low
    power PLC (Powerline Communication) links. LLNs are transitioning
    to an end-to-end IP-based solution to avoid the problem of
    non-interoperable networks interconnected by protocol translation
    gateways and proxies.

    Generally speaking, LLNs have at least five distinguishing
    characteristics:
    - LLNs operate with a hard, very small bound on state.
    - In most cases, LLN optimize for saving energy.
    - Typical traffic patterns are not simply unicast flows (e.g. in some
    cases most if not all traffic can be point to multipoint).
    - In most cases, LLNs will be employed over link layers with 
    restricted frame-sizes, thus a routing protocol for LLNs should be
    specifically
    adapted for such link layers.
    - LLN routing protocols have to be very careful when trading off
    efficiency for generality; many LLN nodes do not have resources to 
    waste.

    These specific properties cause LLNs to have specific routing
    requirements.

    Existing routing protocols such as OSPF, IS-IS, AODV, and OLSR have 
    been evaluated by the working group and have in their current form been 
    found to not satisfy all of these specific routing requirements.

    The Working Group is focused on routing issues for LLN.

    There is a wide scope of application areas for LLNs, including 
    industrial monitoring, building automation (HVAC, lighting, access
    control, 
    fire), connected homes, healthcare, environmental monitoring, urban sensor
    networks (e.g. Smart Grid), asset tracking. The Working Group focuses
    on routing solutions for a subset of these: industrial, connected 
    home, building and urban sensor networks for which routing requirements have
    been specified. These application-specific routing requirement 
    documents will be used for protocol design.

    The Working Group focuses only on IPv6 routing architectural framework
    for these application scenarios. The Framework will take into 
    consideration various aspects including high reliability in the presence
    of time 
    varying loss characteristics and connectivity while permitting low-power 
    operation with very modest memory and CPU pressure in networks
    potentially comprising
    a very large number (several thousands) of nodes.

    The Working Group will pay particular attention to routing security 
    and manageability (e.g., self routing configuration) issues. It will 
    also need to consider the transport characteristic the routing protocol 
    messages will experience. Mechanisms that protect an LLN from congestion
    collapse or
    that establish some degree of fairness between concurrent 
    communication sessions are out of scope of the Working Group. It is
    expected that
    upper-layer applications utilizing LLNs define appropriate mechanisms.
    The solution must include unicast and multicast considerations.

    Work Items:

    - Specification of routing metrics used in path calculation. This
    includes static and dynamic link/node attributes required for routing in
    LLNs.

    - Provide an architectural framework for routing and path selection at
    Layer 3 (Routing for LLN Architecture) that addresses such issues as
    whether LLN routing require a distributed and/or centralized path
    computation models, whether additional hierarchy is necessary and how it
    is 
    applied.

    Manageability will be considered with each approach, along with 
    various trade-offs for maintaining low power operation, including the 
    presence of non-trivial loss and networks with a very large number of nodes.

    - Produce a routing security framework for routing in LLNs.

    - Protocol work: The Working Group will consider specific routing 
    requirements from the four application documents collectively, and
    specify either 
    a new protocol or extend an existing routing protocol in cooperation
    with the 
    relevant Working Group.
    If requirements from the four target application areas cannot be met 
    with a single protocol, the WG may choose to specify or extend more than
    one 
    protocol (this will require a recharter of the WG).

    - Documentation of applicability statement of ROLL routing protocols.

    Goals and Milestones:

    Done  Submit Routing requirements for Industrial applications to the IESG to be considered as an Informational RFC.
    Done  Submit Routing requirements for Connected Home networks applications to the IESG to be considered as an Informational RFC.
    Done  Submit Routing requirements for Building applications to the IESG to be considered as an Informational RFC.
    Done  Submit Routing requirements for Urban networks applications to the IESG to be considered as an Informational RFC.
    Feb 2009  Submit Protocol Survey to the IESG to be considered as an Informational RFC.
    Apr 2009  Submit Security Framework to the IESG to be considered as an Informational RFC
    May 2009  Submit the Routing for LLNs Architecture document to the IESG as an Informational RFC.
    Jul 2009  Submit Routing metrics for LLNs document to the IESG to be considered as a Proposed Standard.
    Jul 2009  Submit first draft of ROLL routing protocol specification as Proposed Standard.
    Nov 2009  Submit first draft of the MIB module of the ROLL routing protocol specification.
    Feb 2010  Submit the ROLL routing protocol specification to the IESG as Proposed Standard.
    Mar 2010  Submit the MIB module of the ROLL routing protocol specification to the IESG as Proposed Standard.
    Apr 2010  Evaluate WG progress, recharter or close.

    Internet-Drafts:

    Industrial Routing Requirements in Low Power and Lossy Networks (67226 bytes)
    Home Automation Routing Requirements in Low Power and Lossy Networks (37325 bytes)
    Overview of Existing Routing Protocols for Low Power and Lossy Networks (64895 bytes)
    Terminology in Low power And Lossy Networks (14014 bytes)
    Building Automation Routing Requirements in Low Power and Lossy Networks (60450 bytes)
    Routing Metrics used for Path Calculation in Low Power and Lossy Networks (24974 bytes)

    Request For Comments:

    Routing Requirements for Urban Low-Power and Lossy Networks (RFC 5548) (47759 bytes)
    IETF Secretariat - Please send questions, comments, and/or suggestions to ietf-web@ietf.org.

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