Routing Over Low power and Lossy networks

The information below is for an older approved charter
Document Charter Routing Over Low power and Lossy networks WG (roll) Snapshot
Title Routing Over Low power and Lossy networks
Last updated 2015-04-04
State Approved
WG State Active
IESG Responsible AD Alvaro Retana
Charter Edit AD Alvaro Retana
Send notices to "Rene Struik" <>, "Michael Richardson" <>, "Alvaro Retana" <>, "Ines Robles" <>


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
  - 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
  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  
  These specific properties cause LLNs to have specific routing
  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
  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
  - 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
   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
  protocol (this will require a recharter of the WG).
  - Documentation of applicability statement of ROLL routing protocols.