6Lo Working Group P. Mariager
Internet-Draft J. Petersen, Ed.
Intended status: Standards Track RTX A/S
Expires: January 4, 2016 Z. Shelby
ARM
M. Van de Logt
Gigaset Communications GmbH
D. Barthel
Orange Labs
July 3, 2015
Transmission of IPv6 Packets over DECT Ultra Low Energy
draft-ietf-6lo-dect-ule-02
Abstract
DECT Ultra Low Energy is a low power air interface technology that is
defined by the DECT Forum and specified by ETSI.
The DECT air interface technology has been used world-wide in
communication devices for more than 20 years, primarily carrying
voice for cordless telephony but has also been deployed for data
centric services.
The DECT Ultra Low Energy is a recent addition to the DECT interface
primarily intended for low-bandwidth, low-power applications such as
sensor devices, smart meters, home automation etc. As the DECT Ultra
Low Energy interface inherits many of the capabilities from DECT, it
benefits from long range, interference free operation, world wide
reserved frequency band, low silicon prices and maturity. There is
an added value in the ability to communicate with IPv6 over DECT ULE
such as for Internet of Things applications.
This document describes how IPv6 is transported over DECT ULE using
6LoWPAN techniques.
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/.
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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 January 4, 2016.
Copyright Notice
Copyright (c) 2015 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
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publication of this document. Please review these documents
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 3
1.2. Terms Used . . . . . . . . . . . . . . . . . . . . . . . 3
2. DECT Ultra Low Energy . . . . . . . . . . . . . . . . . . . . 4
2.1. The DECT ULE Protocol Stack . . . . . . . . . . . . . . . 4
2.2. Link layer roles and topology . . . . . . . . . . . . . . 6
2.3. Addressing Model . . . . . . . . . . . . . . . . . . . . 6
2.4. MTU Considerations . . . . . . . . . . . . . . . . . . . 7
2.5. Additional Considerations . . . . . . . . . . . . . . . . 7
3. Specification of IPv6 over DECT ULE . . . . . . . . . . . . . 7
3.1. Protocol stack . . . . . . . . . . . . . . . . . . . . . 8
3.2. Link model . . . . . . . . . . . . . . . . . . . . . . . 8
3.3. Subnets and Internet connectivity scenarios . . . . . . . 12
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14
6. ETSI Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8.2. Informative References . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
DECT Ultra Low Energy (DECT ULE or just ULE) is an air interface
technology building on the key fundamentals of traditional DECT /
CAT-iq but with specific changes to significantly reduce the power
consumption at the expense of data throughput. DECT ULE devices with
requirements on power consumption will operate on special power
optimized silicon, but can connect to a DECT Gateway supporting
traditional DECT / CAT-iq for cordless telephony and data as well as
the ULE extensions. DECT terminology operates with two major role
definitions: The Portable Part (PP) is the power constrained device,
while the Fixed Part (FP) is the Gateway or base station. This FP
may be connected to the Internet. An example of a use case for DECT
ULE is a home security sensor transmitting small amounts of data (few
bytes) at periodic intervals through the FP, but is able to wake up
upon an external event (burglar) and communicate with the FP.
Another example incorporating both DECT ULE as well as traditional
CAT-iq telephony is an elderly pendant (broche) which can transmit
periodic status messages to a care provider using very little
battery, but in the event of urgency, the elderly person can
establish a voice connection through the pendant to an alarm service.
It is expected that DECT ULE will be integrated into many residential
gateways, as many of these already implements DECT CAT-iq for
cordless telephony. DECT ULE can be added as a software option for
the FP. It is desirable to consider IPv6 for DECT ULE devices due to
the large address space and well-known infrastructure. This document
describes how IPv6 is used on DECT ULE links to optimize power while
maintaining the many benefits of IPv6 transmission. [RFC4944],
[RFC6282] and [RFC6775] specify the transmission of IPv6 over IEEE
802.15.4. DECT ULE has many characteristics similar to those of IEEE
802.15.4, but also differences. Many of the mechanisms defined for
transmission of IPv6 over IEEE 802.15.4 can be applied to the
transmission of IPv6 on DECT ULE links.
This document specifies how to map IPv6 over DECT ULE inspired by
[RFC4944], [RFC6282], [RFC6775] and [I-D.ietf-6lo-btle].
1.1. Requirements Notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
1.2. Terms Used
PP: DECT Portable Part, typically the sensor node
FP: DECT Fixed Part, the gateway
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LLME: Lower Layer Management Entity
RFPI: Radio Fixed Part Identity
IPEI: International Portable Equipment Identity
TPUI: Temporary Portable User Identity
PMID: Portable MAC Identity
PVC: Permanent Virtual Circuit
6LN: DECT Portable part having a role as defined in [RFC6775]
6LBR: DECT Fixed Part having a role as defined in [RFC6775]
2. DECT Ultra Low Energy
DECT ULE is a low power air interface technology that is designed to
support both circuit switched for service, such as voice
communication, and for packet mode data services at modest data rate.
This draft is only addressing the packet mode data service of DECT
ULE.
2.1. The DECT ULE Protocol Stack
The DECT ULE protocol stack consists of the PHY layer operating at
frequencies in the 1880 - 1920 MHz frequency band depending on the
region and uses a symbol rate of 1.152 Mbps. Radio bearers are
allocated by use of FDMA/TDMA/TDD technics.
In its generic network topology, DECT is defined as a cellular
network technology. However, the most common configuration is a star
network with a single FP defining the network with a number of PP
attached. The MAC layer supports both traditional DECT as this is
used for services like discovery, pairing, security features etc.
All these features have been reused from DECT.
The DECT ULE device can switch to the ULE mode of operation,
utilizing the new ULE MAC layer features. The DECT ULE Data Link
Control (DLC) provides multiplexing as well as segmentation and re-
assembly for larger packets from layers above. The DECT ULE layer
also implements per-message authentication and encryption. The DLC
layer ensures packet integrity and preserves packet order, but
delivery is based on best effort.
The current DECT ULE MAC layer standard supports low bandwidth data
broadcast. However the usage of this broadcast service has not yet
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been standardized for higher layers. This document is not
considering usage of this DECT ULE MAC broadcast service in current
version.
In general, communication sessions can be initiated from both FP and
PP side. Depending on power down modes employed in the PP, latency
may occur when initiating sessions from FP side. MAC layer
communication can take place using either connection oriented packet
transfer with low overhead for short sessions or take place using
connection oriented bearers including media reservation. The MAC
layer autonomously selects the radio spectrum positions that are
available within the band and can rearrange these to avoid
interference. The MAC layer has built-in retransmission procedures
in order to improve transmission reliability.
The DECT ULE device will typically incorporate an Application
Programmers Interface (API) as well as common elements known as
Generic Access Profile (GAP) for enrolling into the network. The
DECT ULE stack establishes a permanent virtual circuit (PVC) for the
application layers and provides support for a range of different
application protocols. The used application protocol is negotiated
between the PP and FP when the PVC communication service is
established. This draft defines 6LoWPAN as one of the possible
protocols to negotiate.
+----------------------------------------+
| Applications |
+----------------------------------------+
| Generic Access | ULE Profile |
| Profile | |
+----------------------------------------+
| DECT/Service API | ULE Data API |
+--------------------+-------------------+
| LLME | NWK (MM,CC)| |
+--------------------+-------------------+
| DECT DLC | DECT ULE DLC |
+--------------------+-------------------+
| MAC Layer |
+--------------------+-------------------+
| Physical Layer |
+--------------------+-------------------+
(C-plane) (U-plane)
Figure 1: DECT ULE Protocol Stack
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The DECT ULE stack can be divided into control (C-plane) and user-
data (U-plane) parts shown to the left and to the right in figure 1,
respectively.
2.2. Link layer roles and topology
A FP is assumed to be less constrained than a PP. Hence, in the
primary scenario FP and PP will act as 6LBR and a 6LN, respectively.
This document does only address this primary scenario.
In DECT ULE, at link layer the communication only takes place between
a FP and a PP. A FP is able to handle multiple simultaneous
connections with a number of PP. Hence, in a DECT ULE network using
IPv6, a radio hop is equivalent to an IPv6 link and vice versa.
[DECT ULE PP]-----\ /-----[DECT ULE PP]
\ /
[DECT ULE PP]-------+[DECT ULE FP]+-------[DECT ULE PP]
/ \
[DECT ULE PP]-----/ \-----[DECT ULE PP]
Figure 2: DECT ULE star topology
DECT ULE repeaters are not considered in this document.
2.3. Addressing Model
Each DECT PP is assigned an IPEI during manufacturing. This identity
has the size of 40 bits and is DECT globally unique for the PP and
can be used to constitute the MAC address. However, it cannot be
used to derive a globally unique IID.
When bound to a FP, a PP is assigned a 20 bit TPUI which is unique
within the FP. This TPUI is used for addressing (layer 2) in
messages between FP and PP.
Each DECT FP is assigned a RFPI during manufacturing. This identity
has the size of 40 bits and is globally unique for a FP and can be
used to constitute the MAC address. However, it cannot be used to
derive a globally unique IID.
Alternatively each DECT PP and DECT FP can be assigned a unique
(IEEE) MAC-48 address additionally to the DECT identities to be used
by the 6LoWPAN. With such an approach, the FP and PP have to
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implement a mapping between used MAC-48 addresses and DECT
identities.
2.4. MTU Considerations
Generally the DECT ULE FP and PP may be generating data that fits
into a single MAC Layer packet (38 octets) for periodically
transferred information, depending on application. IP data packets
may be much larger and hence MTU size should be the size of the IP
data packet. The DECT ULE DLC procedures supports segmentation and
reassembly of any MTU size below 65536 octets, but most
implementations do only support smaller values. The default MTU size
in DECT ULE is 500 octets, but it SHALL be configured to fit the
requirements from IPv6 data packets, hence [RFC4944] fragmentation/
reassembly is not required.
It is expected that the LOWPAN_IPHC packet will fulfill all the
requirements for header compression without spending unnecessary
overhead for mesh addressing.
It is important to realize that the usage of larger packets will be
at the expense of battery life, as a large packet inside the DECT ULE
stack will be fragmented into several or many MAC layer packets, each
consuming power to transmit / receive.
2.5. Additional Considerations
The DECT ULE standard allows PP to be registered (bind) to multiple
FP and roaming between these FP. This draft does not consider the
scenarios of PP roaming between multiple FP. The use of repeater
functionality is also not considered in this draft.
3. Specification of IPv6 over DECT ULE
Before any IP-layer communications can take place over DECT ULE, DECT
ULE enabled nodes such as 6LNs and 6LBRs have to find each other and
establish a suitable link-layer connection. The obtain-access-rights
registration and location registration procedures are documented by
ETSI in the specifications [EN300.175-part1-7], [TS102.939-1] and
[TS102.939-2].
DECT ULE technology sets strict requirements for low power
consumption and thus limits the allowed protocol overhead. 6LoWPAN
standards [RFC4944], [RFC6775], and [RFC6282] provide useful
functionality for reducing overhead which can be applied to DECT ULE.
This functionality comprises link-local IPv6 addresses and stateless
IPv6 address autoconfiguration, Neighbor Discovery and header
compression.
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The ULE 6LoWPAN adaptation layer can run directly on this U-plane DLC
layer. Figure 3 illustrates IPv6 over DECT ULE stack.
A significant difference between IEEE 802.15.4 and DECT ULE is that
the former supports both star and mesh topology (and requires a
routing protocol), whereas DECT ULE in it's primary configuration
does not support the formation of multihop networks at the link
layer. In consequence, the mesh header defined in [RFC4944] for mesh
under routing MUST NOT be used in DECT ULE networks. In addition, a
DECT ULE PP node MUST NOT play the role of a 6LoWPAN Router (6LR).
3.1. Protocol stack
In order to enable transmission of IPv6 packets over DECT ULE, a
Permanent Virtual Circuit (PVC) has to be opened between FP and PP.
This MUST be done by setting up a service call from PP to FP. The PP
SHALL specify the <<IWU-ATTRIBUTES>> in a service-change (other)
message before sending a service-change (resume) message as defined
in [TS102.939-1]. The <<IWU-ATTRIBTES>> SHALL define the ULE
Application Protocol Identifier to 0x06 and the MTU size to 1280
octets or larger. The FP MUST send a service-change-accept (resume)
containing a valid paging descriptor. The PP MUST be pageable.
+-------------------+
| UDP/TCP/other |
+-------------------+
| IPv6 |
+-------------------+
|6LoWPAN adapted to |
| DECT ULE |
+-------------------+
| DECT ULE DLC |
+-------------------+
| DECT ULE MAC |
+-------------------+
| DECT ULE PHY |
+-------------------+
Figure 3: IPv6 over DECT ULE Stack
3.2. Link model
The general model is that IPv6 is layer 3 and DECT ULE MAC+DLC is
layer 2. The DECT ULE implements fragmentation and reassembly
functionality and [RFC4944] fragmentation and reassembly function
MUST NOT be used. Since IPv6 requires MTU size of at least 1280
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octets, the DECT ULE connection (PVC) MUST be configured with
equivalent MTU size.
Per this specification, the IPv6 header compression format specified
in [RFC6282] MUST be used. The IPv6 payload length can be derived
from the ULE DLC packet length and the possibly elided IPv6 address
can be reconstructed from the link-layer address, used at the time of
DECT ULE connection establishment, from the ULE MAC packet address,
compression context if any, and from address registration information
(see Section 3.2.2).
Due to DECT ULE star topology, each branch of the star is considered
to be an individual link and thus the PPs cannot directly hear one
another and cannot talk to one another with link-local addresses.
However, the FP acts as a 6LBR for communication between the PPs.
After the FP and PPs have connected at the DECT ULE level, the link
can be considered up and IPv6 address configuration and transmission
can begin. The FP ensures address collisions do not occur.
3.2.1. Stateless address autoconfiguration
A DECT ULE 6LN performs stateless address autoconfiguration as per
[RFC4862]. Following the guidance of [RFC7136], a 64-bit Interface
identifier (IID) for a DECT ULE interface MAY be formed by utilizing
a MAC-48 device address as defined in [RFC2464] "IPv6 over Ethernet"
specification.
Alternatively, the DECT device addresses IPEI, RFPI or TPUI, MAY be
used instead to derive the IID. These DECT devices addresses
consisting of 40, 40 and 20 bits respectively, MUST be expanded with
leading bits to form a 48 bit address. Least significant bit of this
address is the last bit in network order. The expanded leading bits
are all zeros except for 7th bit indicating not global unique. First
bit is set to a one for addresses derived from the RFPI and 2nd bit
is set to one when the address is derived from the PMID. For example
from IPEI=01.23.45.67.89 is derived MAC address equal
02:01:23:45:67:89 and from PMID=0.01.23 is derived MAC address equal
42:00:00:00:01:23.
As defined in [RFC4291], the IPv6 link-local address for a DECT ULE
node is formed by appending the IID, to the prefix FE80::/64, as
shown in Figure 4.
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10 bits 54 bits 64 bits
+----------+-----------------+----------------------+
|1111111010| zeros | Interface Identifier |
+----------+-----------------+----------------------+
Figure 4: IPv6 link-local address in DECT ULE
A 6LN MUST join the all-nodes multicast address.
After link-local address configuration, 6LN sends Router Solicitation
messages as described in [RFC4861] Section 6.3.7.
For non-link-local addresses a 64-bit IID MAY be formed by utilizing
a MAC-48 device address. A 6LN can also use a randomly generated IID
(see Section 3.2.2), for example, as discussed in [I-D.ietf-6man-
default-iids], or use alternative schemes such as Cryptographically
Generated Addresses (CGA) [RFC3972], privacy extensions [RFC4941],
Hash-Based Addresses (HBA, [RFC5535]), or DHCPv6 [RFC3315]. The non-
link-local addresses 6LN generates MUST be registered with 6LBR as
described in Section 3.2.2.
The means for a 6LBR to obtain an IPv6 prefix for numbering the DECT
ULE network is out of scope of this document, but can be, for
example, accomplished via DHCPv6 Prefix Delegation [RFC3633] or by
using Unique Local IPv6 Unicast Addresses (ULA) [RFC4193]. Due to
the link model of the DECT ULE the 6LBR MUST set the "on-link" flag
(L) to zero in the Prefix Information Option [RFC4861]. This will
cause 6LNs to always send packets to the 6LBR, including the case
when the destination is another 6LN using the same prefix.
3.2.2. Neighbor discovery
'Neighbor Discovery Optimization for IPv6 over Low-Power Wireless
Personal Area Networks (6LoWPANs)' [RFC6775] describes the neighbor
discovery approach as adapted for use in several 6LoWPAN topologies,
including the mesh topology. As DECT ULE is considered not to
support mesh networks, hence only those aspects that apply to a star
topology are considered.
The following aspects of the Neighbor Discovery optimizations
[RFC6775] are applicable to DECT ULE 6LNs:
1. For sending Router Solicitations and processing Router
Advertisements the DECT ULE 6LNs MUST, respectively, follow Sections
5.3 and 5.4 of the [RFC6775].
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2. A DECT ULE 6LN MUST NOT register its link-local address. A DECT
ULE 6LN MUST register its non-link-local addresses with the 6LBR by
sending a Neighbor Solicitation (NS) message with the Address
Registration Option (ARO) and process the Neighbor Advertisement (NA)
accordingly. The NS with the ARO option MUST be sent irrespective of
the method used to generate the IID. The 6LN MUST register only one
IPv6 address per available IPv6 prefix.
3.2.3. Unicast and Multicast address mapping
The DECT MAC layer broadcast service is considered inadequate for IP
multicast.
Hence traffic is always unicast between two DECT ULE nodes. Even in
the case where a 6LBR is attached to multiple 6LNs, the 6LBR cannot
do a multicast to all the connected 6LNs. If the 6LBR needs to send
a multicast packet to all its 6LNs, it has to replicate the packet
and unicast it on each link. However, this may not be energy-
efficient and particular care should be taken if the FP is battery-
powered. In the opposite direction, a 6LN can only transmit data to
or through the 6LBR. Hence, when a 6LN needs to transmit an IPv6
multicast packet, the 6LN will unicast the corresponding DECT ULE
packet to the 6LBR. The 6LBR will then forward the multicast packet
to other 6LNs.
3.2.4. Header Compression
Header compression as defined in [RFC6282], which specifies the
compression format for IPv6 datagrams on top of IEEE 802.15.4, is
REQUIRED in this document as the basis for IPv6 header compression on
top of DECT ULE. All headers MUST be compressed according to
[RFC6282] encoding formats. The DECT ULE's star topology structure
and ARO can be exploited in order to provide a mechanism for addess
compression. The following text describes the principles of IPv6
address compression on top of DECT ULE.
3.2.4.1. Link-local Header Compression
In a link-local communication terminated at 6LN and 6LBR, both the
IPv6 source and destination addresses MUST be elided, since the node
knows that the packet is destined for it even if the packet does not
have destination IPv6 address. A node SHALL learn the IID of the
other endpoint of each DECT ULE connection it participates in. By
exploiting this information, a node that receives a PDU containing an
IPv6 packet can infer the corresponding IPv6 source address. A node
MUST maintain a Neighbor Cache, in which the entries include both the
IID of the neighbor and the Device Address that identifies the
neighbor. For the type of communication considered in this
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paragraph, the following settings MUST be used in the IPv6 compressed
header: CID=0, SAC=0, SAM=11, DAC=0, DAM=11.
3.2.4.2. Non-link-local Header Compression
To enable efficient header compression, the 6LBR MUST include 6LoWPAN
Context Option (6CO) [RFC6775] for all prefixes the 6LBR advertises
in Router Advertisements for use in stateless address
autoconfiguration.
When a 6LN transmits an IPv6 packet to a destination using global
Unicast IPv6 addresses, if a context is defined for the prefix of the
6LNs global IPv6 address, the 6LN MUST indicate this context in the
corresponding source fields of the compressed IPv6 header as per
Section 3.1 of [RFC6282], and MUST elide the IPv6 source address.
For this, the 6LN MUST use the following settings in the IPv6
compressed header: CID=1, SAC=1, SAM=11. In this case, the 6LBR can
infer the elided IPv6 source address since 1) the 6LBR has previously
assigned the prefix to the 6LNs; and 2) the 6LBR maintains a Neighbor
Cache that relates the Device Address and the IID of the
corresponding PP. If a context is defined for the IPv6 destination
address, the 6LN MUST also indicate this context in the corresponding
destination fields of the compressed IPv6 header, and MUST elide the
prefix of the destination IPv6 address. For this, the 6LN MUST set
the DAM field of the compressed IPv6 header as CID=1, DAC=1 and
DAM=01 or DAM=11. Note that when a context is defined for the IPv6
destination address, the 6LBR can infer the elided destination prefix
by using the context.
When a 6LBR receives a IPv6 packet having a global Unicast IPv6
address, and the destination of the packet is a 6LN, if a context is
defined for the prefix of the 6LN's global IPv6 address, the 6LBR
MUST indicate this context in the corresponding destination fields of
the compressed IPv6 header, and MUST elide the IPv6 destination
address of the packet before forwarding it to the 6LN. For this, the
6LBR MUST set the DAM field of the IPv6 compressed header as DAM=11.
CID and DAC MUST be set to CID=1 and DAC=1. If a context is defined
for the prefix of the IPv6 source address, the 6LBR MUST indicate
this context in the source fields of the compressed IPv6 header, and
MUST elide that prefix as well. For this, the 6LBR MUST set the SAM
field of the IPv6 compressed header as CID=1, SAC=1 and SAM=01 or
SAM=11.
3.3. Subnets and Internet connectivity scenarios
In a typical scenario, the DECT ULE network is connected to the
Internet as shown in the Figure 5. In this scenario, the DECT ULE
network is deployed as one subnet, using one /64 IPv6 prefix. The
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6LBR is acting as router and forwarding packets between 6LNs and to
and from Internet.
A degenerate scenario can be imagined where a PP is acting as 6LBR
and providing Internet connectivity for the FP. How the FP could
then further provide Internet connectivity to other PP, possibly
connected to the FP, is out of the scope of this document.
6LN
\ ____________
\ / \
6LN ---- 6LBR --- | Internet |
/ \____________/
/
6LN
<-- DECT ULE -->
Figure 5: DECT ULE network connected to the Internet
In some scenarios, the DECT ULE network may transiently or
permanently be an isolated network as shown in the Figure 6. In this
case the whole DECT ULE network consists of a single subnet with
multiple links, where 6LBR is routing packets between 6LNs.
6LN 6LN
\ /
\ /
6LN --- 6LBR --- 6LN
/ \
/ \
6LN 6LN
<------ DECT ULE ----->
Figure 6: Isolated DECT ULE network
In the isolated network scenario, communications between 6LN and 6LBR
can use IPv6 link-local methodology, but for communications between
different PP, the FP has to act as 6LBR, number the network with ULA
prefix [RFC4193], and route packets between PP.
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4. IANA Considerations
There are no IANA considerations related to this document.
5. Security Considerations
The secure transmission of speech over DECT will be based on the
DSAA2 and DSC2 work developed by the DF Security group / ETSI TC DECT
and the ETSI SAGE Security expert group.
DECT ULE communications are secured at the link-layer (DLC) by
encryption and per-message authentication through CCM mode (Counter
with CBC-MAC) similar to [RFC3610]. The underlying algorithm for
providing encryption and authentication is AES128.
The DECT ULE pairing procedure generates a master authentication key
(UAK) and during location registration procedure or when the
permanent virtual circuit are established, the session security keys
are generated. Session security keys may be renewed regularly. The
generated security keys (UAK and session security keys) are
individual for each FP-PP binding, hence all PP in a system have
different security keys. DECT ULE PPs do not use any shared
encryption key.
The IPv6 address configuration as described in Section 3.2.1 allows
implementations the choice to support, for example, [I-D.ietf-6man-
default-iids], [RFC3972], [RFC4941] or [RFC5535] for non-link-local
addresses.
6. ETSI Considerations
ETSI is standardizing a list of known application layer protocols
that can use the DECT ULE permanent virtual circuit packet data
service. Each protocol is identified by a unique known identifier,
which is exchanged in the service-change procedure as defined in
[TS102.939-1]. The IPv6/6LoWPAN as described in this document is
considered as an application layer protocol on top of DECT ULE. In
order to provide interoperability between 6LoWPAN / DECT ULE devices
a common protocol identifier for 6LoWPAN is standardized by ETSI.
The ETSI DECT ULE Application Protocol Identifier is specified to
0x06 for 6LoWPAN [TS102.939-1].
7. Acknowledgements
We are grateful to the members of the IETF 6lo working group; this
document borrows liberally from their work.
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Ralph Droms has provided valuable feedback for this draft.
8. References
8.1. Normative References
[EN300.175-part1-7]
ETSI, "Digital Enhanced Cordless Telecommunications
(DECT); Common Interface (CI);", March 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet
Networks", RFC 2464, December 1998.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic
Host Configuration Protocol (DHCP) version 6", RFC 3633,
December 2003.
[RFC4193] Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
Addresses", RFC 4193, October 2005.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, February 2006.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy
Extensions for Stateless Address Autoconfiguration in
IPv6", RFC 4941, September 2007.
[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, September 2007.
[RFC6282] Hui, J. and P. Thubert, "Compression Format for IPv6
Datagrams over IEEE 802.15.4-Based Networks", RFC 6282,
September 2011.
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[RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann,
"Neighbor Discovery Optimization for IPv6 over Low-Power
Wireless Personal Area Networks (6LoWPANs)", RFC 6775,
November 2012.
[RFC7136] Carpenter, B. and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, February 2014.
[TS102.939-1]
ETSI, "Digital Enhanced Cordless Telecommunications
(DECT); Ultra Low Energy (ULE); Machine to Machine
Communications; Part 1: Home Automation Network (phase
1)", March 2015.
[TS102.939-2]
ETSI, "Digital Enhanced Cordless Telecommunications
(DECT); Ultra Low Energy (ULE); Machine to Machine
Communications; Part 2: Home Automation Network (phase
2)", March 2015.
8.2. Informative References
[I-D.ietf-6lo-btle]
Nieminen, J., Savolainen, T., Isomaki, M., Patil, B.,
Shelby, Z., and C. Gomez, "IPv6 over BLUETOOTH(R) Low
Energy", draft-ietf-6lo-btle-14 (work in progress), June
2015.
[I-D.ietf-6man-default-iids]
Gont, F., Cooper, A., Thaler, D., and S. LIU,
"Recommendation on Stable IPv6 Interface Identifiers",
draft-ietf-6man-default-iids-04 (work in progress), June
2015.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3610] Whiting, D., Housley, R., and N. Ferguson, "Counter with
CBC-MAC (CCM)", RFC 3610, September 2003.
[RFC3972] Aura, T., "Cryptographically Generated Addresses (CGA)",
RFC 3972, March 2005.
[RFC5535] Bagnulo, M., "Hash-Based Addresses (HBA)", RFC 5535, June
2009.
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Authors' Addresses
Peter B. Mariager
RTX A/S
Stroemmen 6
DK-9400 Noerresundby
Denmark
Email: pm@rtx.dk
Jens Toftgaard Petersen (editor)
RTX A/S
Stroemmen 6
DK-9400 Noerresundby
Denmark
Email: jtp@rtx.dk
Zach Shelby
Sensinode
150 Rose Orchard
San Jose, CA 95134
USA
Email: zach.shelby@arm.com
Marco van de Logt
Gigaset Communications GmbH
Frankenstrasse 2
D-46395 Bocholt
Germany
Email: marco.van-de-logt@gigaset.com
Dominique Barthel
Orange Labs
28 chemin du Vieux Chene
38243 Meylan
France
Email: dominique.barthel@orange.com
Mariager, et al. Expires January 4, 2016 [Page 17]
