IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs): Overview, Assumptions, Problem Statement, and Goals
RFC 4919

Network Working Group                                     N. Kushalnagar
Request for Comments: 4919                                    Intel Corp
Category: Informational                                    G. Montenegro
                                                   Microsoft Corporation
                                                           C. Schumacher
                                                             Danfoss A/S
                                                             August 2007

    IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs):
          Overview, Assumptions, Problem Statement, and Goals

Status of This Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The IETF Trust (2007).

Abstract

   This document describes the assumptions, problem statement, and goals
   for transmitting IP over IEEE 802.15.4 networks.  The set of goals
   enumerated in this document form an initial set only.

Table of Contents

   1. Introduction ....................................................2
   2. Overview ........................................................2
   3. Assumptions .....................................................3
   4. Problems ........................................................4
      4.1. IP Connectivity ............................................4
      4.2. Topologies .................................................5
      4.3. Limited Packet Size ........................................6
      4.4. Limited Configuration and Management .......................6
      4.5. Service Discovery ..........................................6
      4.6. Security ...................................................6
   5. Goals ...........................................................7
   6. Security Considerations .........................................9
   7. Acknowledgements ...............................................10
   8. References .....................................................10
      8.1. Normative References ......................................10
      8.2. Informative References ....................................10

Kushalnagar, et al.          Informational                      [Page 1]
RFC 4919               6LoWPAN Problems and Goals            August 2007

1.  Introduction

   Low-power wireless personal area networks (LoWPANs) comprise devices
   that conform to the IEEE 802.15.4-2003 standard by the IEEE
   [IEEE802.15.4].  IEEE 802.15.4 devices are characterized by short
   range, low bit rate, low power, and low cost.  Many of the devices
   employing IEEE 802.15.4 radios will be limited in their computational
   power, memory, and/or energy availability.

   This document gives an overview of LoWPANs and describes how they
   benefit from IP and, in particular, IPv6 networking.  It describes
   LoWPAN requirements with regards to the IP layer and the above, and
   spells out the underlying assumptions of IP for LoWPANs.  Finally, it
   describes problems associated with enabling IP communication with
   devices in a LoWPAN, and defines goals to address these in a
   prioritized manner.  Admittedly, not all items on this list may be
   necessarily appropriate tasks for the IETF.  Nevertheless, they are
   documented here to give a general overview of the larger problem.
   This is useful both to structure work within the IETF as well as to
   better understand how to coordinate with external organizations.

2.  Overview

   A LoWPAN is a simple low cost communication network that allows
   wireless connectivity in applications with limited power and relaxed
   throughput requirements.  A LoWPAN typically includes devices that
   work together to connect the physical environment to real-world
   applications, e.g., wireless sensors.  LoWPANs conform to the IEEE
   802.15.4-2003 standard [IEEE802.15.4].

   Some of the characteristics of LoWPANs are as follows:

   1.   Small packet size.  Given that the maximum physical layer packet
        is 127 bytes, the resulting maximum frame size at the media
        access control layer is 102 octets.  Link-layer security imposes
        further overhead, which in the maximum case (21 octets of
        overhead in the AES-CCM-128 case, versus 9 and 13 for AES-CCM-32
        and AES-CCM-64, respectively), leaves 81 octets for data
        packets.

   2.   Support for both 16-bit short or IEEE 64-bit extended media
        access control addresses.

   3.   Low bandwidth.  Data rates of 250 kbps, 40 kbps, and 20 kbps for
        each of the currently defined physical layers (2.4 GHz, 915 MHz,
        and 868 MHz, respectively).

   4.   Topologies include star and mesh operation.