ROLL J. Guo
Internet-Draft P. Orlik
Intended status: Standards Track G. Bhatti
Expires: June 30, 2013 Mitsubishi Electric Research Laboratories
December 27, 2012
Loop Free RPL
draft-guo-roll-loop-free-rpl-01
Abstract
IETF has been developing IPv6 based standards for Low-power and Lossy
Networks (LLNs) to meet requirements of constrained applications,
such as field monitoring, inventory control and so on. IPv6 Routing
Protocol for LLNs (RPL) has been published in [RFC6550]. Based on
routing metrics and constraints [RFC6551], RPL builds Directed
Acyclic Graph (DAG) topology to establish bidirectional routes for
LLNs for traffic types of multipoint-to-point, point-to-multipoint,
and point-to-point. RPL routes are optimized for traffic to or from
one or more roots that act as sinks. As a result, a DAG is
partitioned into one or more Destination Oriented DAGs (DODAGs), one
DODAG per sink. RPL is widely considered as a feasible routing
protocol for LLNs. However, DODAG loops and lack of a loop free DODAG
local repair mechanism are two open issues to be addressed. This
draft introduces an alternative rank and an Objective Function to
eliminate DODAG loops in RPL. Based on the proposed rank and
Objective Function, this draft introduces a loop free RPL.
Guo, et al. Expires June 30, 2013 [Page 1]
Internet-Draft Loop Free RPL July 1, 2012
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 30, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Guo, et al. Expires June 30, 2013 [Page 2]
Internet-Draft Loop Free RPL July 1, 2012
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Alternative Rank . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Alternative Rank Definition . . . . . . . . . . . . . . . . 6
3.2. Rank Split Operation . . . . . . . . . . . . . . . . . . . 7
4. ICMPv6 RPL Control Message Extension . . . . . . . . . . . . . . 7
4.1. Format of the Modified DIO Base Object . . . . . . . . . . 7
4.2. DODAG Repair Request (DRQ) . . . . . . . . . . . . . . . . 8
4.2.1. Format of the DRQ Base Object . . . . . . . . . . . 8
4.2.2. Secure DRQ . . . . . . . . . . . . . . . . . . . . . 9
4.2.3. DRQ Options . . . . . . . . . . . . . . . . . . . . 9
4.3. DODAG Repair Reply (DRP) . . . . . . . . . . . . . . . . . 10
4.3.1. Format of the DRP Base Object . . . . . . . . . . . 10
4.3.2. Secure DRP . . . . . . . . . . . . . . . . . . . . 11
4.3.3. DRP Options . . . . . . . . . . . . . . . . . . . . 11
4.4. Format of the Path Option . . . . . . . . . . . . . . . . 11
5. DODAG Construction . . . . . . . . . . . . . . . . . . . . . . 12
6. DODAG Local Repair . . . . . . . . . . . . . . . . . . . . . . 13
6.1. DODAG Local Repair in Storing Mode . . . . . . . . . . . . 14
6.1.1. DRQ Message Processing . . . . . . . . . . . . . . 14
6.1.2. DRP Message Processing . . . . . . . . . . . . . . 15
datatracker.ietf.org