Routing Over Low power and Lossy networks (roll)
------------------------------------------------

 Charter
 Last Modified: 2009-06-22

 Current Status: Active Working Group

 Chair(s):
     JP Vasseur  <jpv@cisco.com>
     David Culler  <culler@eecs.berkeley.edu>

 Routing Area Director(s):
     Stewart Bryant  <stbryant@cisco.com>
     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:

Posted Revised         I-D Title   <Filename>
------ ------- --------------------------------------------
Oct 2008 Mar 2010   <draft-ietf-roll-terminology-03.txt>
                Terminology in Low power And Lossy Networks 

Oct 2008 Jan 2010   <draft-ietf-roll-building-routing-reqs-09.txt>
                Building Automation Routing Requirements in Low Power and Lossy 
                Networks 

May 2009 Jun 2010   <draft-ietf-roll-routing-metrics-07.txt>
                Routing Metrics used for Path Calculation in Low Power and 
                Lossy Networks 

Aug 2009 May 2010   <draft-ietf-roll-rpl-08.txt>
                RPL: IPv6 Routing Protocol for Low power and Lossy Networks 

Dec 2009 Jun 2010   <draft-ietf-roll-of0-02.txt>
                RPL Objective Function 0 

Mar 2010 Apr 2010   <draft-ietf-roll-trickle-01.txt>
                The Trickle Algorithm 

Mar 2010 Mar 2010   <draft-ietf-roll-security-framework-00.txt>
                A Security Framework for Routing over Low Power and Lossy 
                Networks 

 Request For Comments:

  RFC   Stat Published     Title
------- -- ----------- ------------------------------------
RFC5548 I    May 2009    Routing Requirements for Urban Low-Power and Lossy 
                       Networks 

RFC5673 I    Oct 2009    Industrial Routing Requirements in Low Power and Lossy 
                       Networks 

RFC5826 I    Apr 2010    Home Automation Routing Requirements in Low Power and 
                       Lossy Networks