Hi,

I have reviewed this document as part of the security directorate's 
ongoing effort to review all IETF documents being processed by the 
IESG.  These comments were written primarily for the benefit of the 
security area directors.  Document editors and WG chairs should treat 
these comments just like any other last call comments.

   The Routing Protocol for Low Power and Lossy Networks (RPL)
   specification defines a generic Distance Vector protocol that is
   adapted to a variety of networks types by the application of specific
   Objective Functions.  An Objective Function defines how a RPL node
   selects and optimizes routes within a RPL Instance based on the
   information objects available.  This document specifies a basic
   Objective Function that relies only on the objects that are defined
   in RPL and does not use any extension.

The security considerations section references the same I.D. twice:

   described in [I-D.ietf-roll-rpl] and [I-D.ietf-roll-rpl].  This

I suspect that the second instance is a typo and instead it should
refer to a different specification?

Beyond that, I see no security issues with this document.

-derek

-- 
       Derek Atkins                 617-623-3745
       derek at ihtfp.com             www.ihtfp.com
       Computer and Internet Security Consultant