6LoWPAN Working Group J. Nieminen, Ed.
Internet-Draft T. Savolainen, Ed.
Intended status: Standards Track M. Isomaki
Expires: March 21, 2013 Nokia
B. Patil
Z. Shelby
Sensinode
C. Gomez
Universitat Politecnica de
Catalunya/i2CAT
September 17, 2012
Transmission of IPv6 Packets over Bluetooth Low Energy
draft-ietf-6lowpan-btle-10
Abstract
Bluetooth Low Energy is a low power air interface technology defined
by the Bluetooth Special Interest Group (BT-SIG). The standard
Bluetooth radio has been widely implemented and available in mobile
phones, notebook computers, audio headsets and many other devices.
The low power version of Bluetooth is a new specification and enables
the use of this air interface with devices such as sensors, smart
meters, appliances, etc. The low power variant of Bluetooth is
currently specified in revision 4.0 of the Bluetooth specifications
(Bluetooth 4.0). This document describes how IPv6 is transported
over Bluetooth Low Energy 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/.
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 March 21, 2013.
Copyright Notice
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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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Bluetooth Low Energy . . . . . . . . . . . . . . . . . . . . . 3
2.1. Bluetooth Low Energy stack . . . . . . . . . . . . . . . . 4
2.2. Link layer roles and topology . . . . . . . . . . . . . . 4
2.3. BT-LE device addressing . . . . . . . . . . . . . . . . . 5
2.4. BT-LE packets sizes and MTU . . . . . . . . . . . . . . . 5
3. Specification of IPv6 over Bluetooth Low Energy . . . . . . . 6
3.1. Protocol stack . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Link model . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2.1. Stateless address autoconfiguration . . . . . . . . . 8
3.2.2. Neighbor discovery . . . . . . . . . . . . . . . . . . 8
3.2.3. Header compression . . . . . . . . . . . . . . . . . . 9
3.2.4. Unicast and Multicast address mapping . . . . . . . . 10
3.3. Internet connectivity scenarios . . . . . . . . . . . . . 10
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
5. Security Considerations . . . . . . . . . . . . . . . . . . . 11
6. Additional contributors . . . . . . . . . . . . . . . . . . . 12
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.1. Normative References . . . . . . . . . . . . . . . . . . . 12
8.2. Informative References . . . . . . . . . . . . . . . . . . 13
Appendix A. Bluetooth Low Energy fragmentation and L2CAP Modes . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
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1. Introduction
Bluetooth Low Energy (BT-LE) is a radio technology targeted for
devices that operate with coin cell batteries or minimalistic power
sources, which means that low power consumption is essential. BT-LE
is an especially attractive technology for Internet of Things
applications, such as health monitors, environmental sensing,
proximity applications and many others.
Considering the potential for the exponential growth in the number of
sensors and Internet connected devices and things, IPv6 is an ideal
protocol due to the large address space it provides. In addition,
IPv6 provides tools for stateless address autoconfiguration, which is
particularly suitable for sensor network applications and nodes which
have very limited processing power or lack a full-fledged operating
system.
[RFC4944] specifies the transmission of IPv6 over IEEE 802.15.4. The
Bluetooth Low Energy link in many respects has similar
characteristics to that of IEEE 802.15.4. Many of the mechanisms
defined in [RFC4944] can be applied to the transmission of IPv6 on
Bluetooth Low Energy links. This document specifies the details of
IPv6 transmission over Bluetooth Low Energy links.
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 RFC 2119 [RFC2119].
The terms 6LN, 6LR and 6LBR are defined as in [I-D.ietf-6lowpan-nd].
2. Bluetooth Low Energy
BT-LE is designed for transferring small amounts of data infrequently
at modest data rates at a very low cost per bit. Bluetooth Special
Interest Group has introduced two trademarks, Bluetooth Smart for
single-mode devices (a device that only supports BT-LE) and Bluetooth
Smart Ready for dual-mode devices. In the rest of the draft, the
term BT-LE refers to both types of devices.
BT-LE is an integral part of the BT 4.0 specification [BTCorev4.0].
Devices such as mobile phones, notebooks, tablets and other handheld
computing devices which include BT 4.0 chipsets also have the low-
energy functionality of Bluetooth. BT-LE is also included in many
different types of accessories that collaborate with mobile devices
such as phones, tablets and notebook computers. An example of a use
case for a BT-LE accessory is a heart rate monitor that sends data
via the mobile phone to a server on the Internet.
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2.1. Bluetooth Low Energy stack
The lower layer of the BT-LE stack consists of the Physical (PHY) and
the Link Layer (LL). The Physical Layer transmits and receives the
actual packets. The Link Layer is responsible for providing medium
access, connection establishment, error control and flow control.
The upper layer consists of the Logical Link Control and Adaptation
Protocol (L2CAP), Generic Attribute protocol (GATT) and Generic
Access Profile (GAP) as shown in Figure 1. GATT and BT-LE profiles
together enable the creation of applications in a standardized way
without using IP. L2CAP provides multiplexing capability by
multiplexing the data channels from the above layers. L2CAP also
provides fragmentation and reassembly for large data packets.
+----------------------------------------+------------------+
| Applications |
+----------------------------------------+------------------+
| Generic Attribute Profile | Generic Access |
+----------------------------------------+ Profile |
| Attribute Protocol |Security Manager | |
+--------------------+-------------------+------------------+
| Logical Link Control and Adaptation |
+--------------------+-------------------+------------------+
| Host Controller Interface |
+--------------------+-------------------+------------------+
| Link Layer | Direct Test Mode |
+--------------------+-------------------+------------------+
| Physical Layer |
+--------------------+-------------------+------------------+
Figure 1: BT-LE Protocol Stack
2.2. Link layer roles and topology
BT-LE defines two Link Layer roles: the Master Role and the Slave
Role. A device in the Master Role, which is called master, can
manage multiple simultaneous connections with a number of devices in
the Slave Role, called slaves. A slave can only be connected to a
single master. Hence, a BT-LE network (i.e. a BT-LE piconet) follows
a star topology shown in the Figure 2. This specification primarily
addresses the situation where the BT-LE Slave is a host but not a
router at the IP level.
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[BTLE-Slave]-----\ /-----[BTLE-Slave]
\ /
[BTLE-Slave]-----/[BTLE-Master]/-----[BTLE-Slave]
/ \
[BTLE-Slave]-----/ \-----[BTLE-Slave]
Figure 2: BT-LE Star Topology
A master is assumed to be less constrained than a slave. Hence,
master and slave can act as 6LoWPAN Border Router (6LBR) and host,
respectively.
In BT-LE, communication only takes place between a master and a
slave. Hence, in a BT-LE network using IP, a radio hop is equivalent
to an IP link and vice versa.
2.3. BT-LE device addressing
Every BT-LE device is identified by a unique 48 bit Bluetooth Device
Address (BD_ADDR). A Bluetooth Smart device such as a sensor can use
a public or a random device address (generated internally). The
public address is created according to the IEEE 802-2001 standard
[IEEE802-2001] and using a valid Organizationally Unique Identifier
(OUI) obtained from the IEEE Registration Authority.
2.4. BT-LE packets sizes and MTU
Maximum size of the payload in the BT-LE data channel PDU is 27
bytes. Depending on the L2CAP mode in use, the amount of data
available for transporting IP bytes in the single BT-LE data channel
PDU ranges between 19 and 27 octets. For power efficient
communication between two BT-LE devices, data and its header should
fit in a single BT-LE data channel PDU. However, IPv6 requires
support for an MTU of 1280 bytes. An inherent function of the BT-LE
L2CAP layer, called Fragmentation and Recombination (FAR), can assist
in transferring IPv6 packets that do not fit in a single BT-LE data
channel PDU.
The maximum IP datagram size that can be transported by L2CAP depends
on the L2CAP mode. The Basic L2CAP Mode allows a maximum payload
size (i.e. IP datagram size) of 65535 bytes per L2CAP PDU. The rest
of the L2CAP modes allow a maximum payload size that ranges between
65527 and 65533 bytes per L2CAP PDU. Appendix A describes FAR
operation and five L2CAP Modes.
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3. Specification of IPv6 over Bluetooth Low Energy
BT-LE technology sets strict requirements for low power consumption
and thus limits the allowed protocol overhead. 6LoWPAN standards
[RFC4944], [I-D.ietf-6lowpan-nd] and [RFC6282] provide useful generic
functionality like header compression [Section 3.2.3], link-local
IPv6 addresses, Neighbor Discovery [Section 3.2.2] and stateless IP-
address autoconfiguration [Section 3.2.1] for reducing the overhead
in 802.15.4 networks. This functionality can be partly applied to
BT-LE.
A significant difference between IEEE 802.15.4 and BT-LE is that the
former supports both star and mesh topology (and requires a routing
protocol), whereas BT-LE does not currently 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 BT-LE
networks. In addition, a BT-LE device MUST NOT play the role of a
6LoWPAN Router (6LR).
3.1. Protocol stack
In order to enable transmission of IPv6 packets over BT-LE, a new
fixed L2CAP channel ID is being reserved for IPv6 traffic by the BT-
SIG. A request for allocation of a new fixed channel ID for IPv6
traffic by the BT-SIG should be submitted through the liaison process
or formal communique from the 6lowpan chairs and respective area
directors. Until a channel ID is allocated by BT-SIG, the channel ID
0x0007 is recommended for experimentation. Once the channel ID is
allocated, the allocated value MUST be used. Figure 3 illustrates
IPv6 over BT-LE stack. UDP/TCP are provided as examples of a
transport protocol, but the stack can be used by other transport
protocols as well.
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+-------------------+
| UDP/TCP |
+-------------------+
| IPv6 |
+-------------------+
| 6LoWPAN adapted |
| to BT-LE |
+-------------------+
| BT-LE L2CAP |
+-------------------+
| BT-LE Link Layer |
+-------------------+
| BT-LE Physical |
+-------------------+
Figure 3: IPv6 over BT-LE Stack
3.2. Link model
The concept of IP link (layer 3) and the physical link (combination
of PHY and MAC) needs to be clear and the relationship has to be well
understood in order to specify the addressing scheme for transmitting
IPv6 packets over the BT-LE link. [RFC4861] defines a link as "a
communication facility or medium over which nodes can communicate at
the link layer, i.e., the layer immediately below IP."
In the case of BT-LE, L2CAP is an adaptation layer that supports the
transmission of IPv6 packets. L2CAP also provides multiplexing
capability in addition to FAR functionality. This specification
requires that FAR functionality MUST be provided in the L2CAP layer
up to the IPv6 minimum MTU of 1280 bytes. The corresponding L2CAP
Mode MUST be Basic Mode. Since FAR in BT-LE is a function of the
L2CAP layer, fragmentation functionality as defined in [RFC4944] MUST
NOT be used in BT-LE networks. This specification also assumes the
IPv6 header compression format specified in [RFC 6282]. It is also
assumed that the IPv6 payload length can be inferred from the L2CAP
header length and also assumes that IPv6 addresses assigned to
6LoWPAN interfaces are formed with an IID derived directly from the
48-bit Bluetooth device addresses, as described in subsection 3.2.1.
The BT-LE link between two communicating nodes can be considered to
be a point-to-point or point-to-multipoint link. When one of the
communicating nodes is in the role of a master, then the link can be
viewed as a point-to-multipoint link.
When a host connects to another BT-LE device the link is up and IP
address configuration and transmission can occur.
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3.2.1. Stateless address autoconfiguration
A BT-LE 6LN performs stateless address autoconfiguration as per
[RFC4862]. This specification mandates that the 64 bit Interface
Identifier (IID) for a BT-LE interface MUST be formed using a
Bluetooth Device Address that is a 48-bit unique public Bluetooth
address, [Section 2.3] as per the "IPv6 over Ethernet" specification
[RFC2464]. A BT-LE 6LN node MAY use this EUI-64 based IID or a
randomly generated IID [Section 3.2.2] for stateless address
autoconfiguration. Since the 48-bit public Bluetooth address is
globally unique, the "Universal/Local" (U/L) bit MUST be set to 0.
As defined in [RFC4291], the IPv6 link-local address for a BT-LE node
is formed by appending the IID, to the prefix FE80::/64, as depicted
in Figure 4.
The tool for a gateway to obtain an IPv6 prefix for numbering the
BT-LE network is out of scope of this document, but can for example
be accomplished via DHCPv6 Prefix Delegation [RFC3633]. The used
IPv6 prefix may change due to the gateway's movement.
3.2.2. Neighbor discovery
[I-D.ietf-6lowpan-nd] describes the neighbor discovery approach as
adapted for use in several 6LoWPAN topologies, including the mesh
topology. BT-LE does not support mesh networks and hence only those
aspects of the [I-D.ietf-6lowpan-nd] that apply to a star topology
are considered.
The following aspects of 6lowpan-nd are applicable to BT-LE 6LNS:
1. A BT-LE 6LN MUST register its address with the router by sending
a NS message with the ARO option and process the NA accordingly. The
NS with the ARO option SHOULD be sent irrespective of whether the IID
is derived from the unique 48 bit BT-LE device address or the IID is
a random value that is generated as per the privacy extensions for
stateless address autoconfiguration [RFC4941]. Although [RFC 4941]
permits the use of deprecated addresses for old connections, in this
specification we mandate that one interface MUST NOT use more than
one IID at any one time.
2. Sending a Router solicitation (RS) and processing Router
advertisements by BT-LE 6LNs MUST follow Sections 5.3 and 5.4
respectively of [I-D.ietf-6lowpan-nd].
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10 bits 54 bits 64 bits
+----------+-----------------+----------------------+
|1111111010| zeros | Interface Identifier |
+----------+-----------------+----------------------+
Figure 4: IPv6 link-local address in BT-LE
3.2.3. 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 BT-LE. All headers MUST be compressed according to RFC 6282
encoding formats. In BT-LE the star topology structure can be
exploited in order to provide a mechanism for IID compression. The
following text describes the principles of IPv6 address compression
on top of BT-LE.
In a link-local communication, both the IPv6 source and destination
addresses MUST be elided [RFC6282], since the device knows that the
packet is destined for it even if the packet does not have
destination IPv6 address. On the other hand, a node SHALL learn the
IID of the other endpoint of each L2CAP connection it participates
in. By exploiting this information, a node that receives a data
channel PDU containing an IPv6 packet (or a part of it) can infer the
corresponding IPv6 source address. The device 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 paragraph, the following
settings MUST be used in the IPv6 compressed header: CID=0, SAC=0,
SAM=11, DAC=0, DAM=11.
When a BT-LE slave transmits an IPv6 packet to a remote destination
using global Unicast IPv6 addresses, if a context is defined for the
prefix of the slave global IPv6 address, the slave MUST indicate this
context in the corresponding source fields of the compressed IPv6
header as per Section 3.1 of [RFC 6282], and MUST elide the IPv6
source address. For this, the slave MUST use the following settings
in the IPv6 compressed header: CID=1, SAC=1, SAM=11. In this case,
the 6LBR/master can infer the elided IPv6 source address since 1) the
master/6LBR has previously assigned the prefix to the slaves; and 2)
the master/6LBR maintains a Neighbor Cache that relates the Device
Address and the IID of the corresponding slave. If a context is
defined for the IPv6 destination address, the slave MUST also
indicate this context in the corresponding destination fields of the
compressed IPv6 header, and MUST elide the prefix of the destination
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IPv6 address. For this, the slave MUST set the DAM field of the
compressed IPv6 header as DAM=01 (if the context covers a 64-bit
prefix) or as DAM=11 (if the context covers a full, 128-bit address).
CID and DAC MUST be set to CID=1 and DAC=1. Note that when a context
is defined for the IPv6 destination address, the 6LBR/master can
infer the elided destination prefix by using the context.
When a master/6LBR receives an IPv6 packet sent by a remote node
outside the BT-LE network, and the destination of the packet is a
slave, if a context is defined for the prefix of the slave global
IPv6 address, the master/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 slave. For this, the master/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 master/6LBR MUST indicate this context
in the source fields of the compressed IPv6 header, and MUST elide
that prefix as well. For this, the master/6LBR MUST set the SAM
field of the IPv6 compressed header as SAM=01 (if the context covers
a 64-bit prefix) or SAM=11 (if the context covers a full, 128-bit
address). CID and SAC MUST be set to CID=1 and SAC=1.
3.2.4. Unicast and Multicast address mapping
The BT-LE link layer does not support multicast. Hence traffic is
always unicast between two BT-LE devices. Even in the case where a
master is attached to multiple slave BT-LE devices, the master device
cannot do a multicast to all the connected slave devices. If the
master device needs to send a multicast packet to all its slave
devices, it has to replicate the packet and unicast it on each link.
However, this may not be energy-efficient and particular care must be
taken if the master is battery-powered. In the opposite direction, a
slave can only transmit data to a single destination (i.e. the
master). Hence, if a slave transmits an IPv6 multicast packet, the
slave can unicast the corresponding BT-LE packet to the master. The
master MUST provide a table for mapping different types of multicast
addresses (all-nodes, all-routers and solicited-node multicast
addresses) to the corresponding IIDs and Device Addresses.
3.3. Internet connectivity scenarios
In a typical scenario, the BT-LE network is connected to the Internet
as shown in the Figure 5.
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h ____________
\ / \
h ---- 6LBR --- | Internet |
/ \____________/
h
h: host
<-- BT-LE --> 6LBR: 6LoWPAN Border Router
Figure 5: BT-LE network connected to the Internet
In some scenarios, the BT-LE network may transiently or permanently
be an isolated network as shown in the Figure 6.
h h h: host
\ / 6LBR: 6LoWPAN Border Router
h --- 6LBR -- h
/ \
h h
Figure 6: Isolated BT-LE network
Host-to-master and master-to-host communication MUST use the same
mechanisms as would be used in global IPv6 communications. The
gateway is used to route the packets to one of its slaves.
4. IANA Considerations
There are no IANA considerations related to this document.
5. Security Considerations
The transmission of IPv6 over BT-LE links has similar requirements
and concerns for security as for IEEE 802.15.4. IPv6 over BT-LE
SHOULD be protected by using BT-LE Link Layer security.
BT-LE Link Layer supports encryption and authentication by using the
Counter with CBC-MAC (CCM) mechanism [RFC3610] and a 128-bit AES
block cipher. Upper layer security mechanisms may exploit this
functionality when it is available. (Note: CCM does not consume
bytes from the maximum per-packet L2CAP data size, since the link
layer data unit has a specific field for them when they are used.)
Key management in BT-LE is provided by the Security Manager Protocol
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(SMP), as defined in [BTCorev4.0].
6. Additional contributors
Kanji Kerai, Jari Mutikainen, David Canfeng-Chen and Minjun Xi from
Nokia have contributed significantly to this document.
7. Acknowledgements
The Bluetooth, Bluetooth Smart and Bluetooth Smart Ready marks are
registred trademarks owned by Bluetooth SIG, Inc.
Samita Chakrabarti and Erik Nordmark have provided valuable feedback
for this draft.
8. References
8.1. Normative References
[BTCorev4.0]
BLUETOOTH Special Interest Group, "BLUETOOTH Specification
Version 4.0", June 2010.
[I-D.ietf-6lowpan-nd]
Shelby, Z., Chakrabarti, S., and E. Nordmark, "Neighbor
Discovery Optimization for Low Power and Lossy Networks
(6LoWPAN)", draft-ietf-6lowpan-nd-21 (work in progress),
August 2012.
[IEEE802-2001]
Institute of Electrical and Electronics Engineers (IEEE),
"IEEE 802-2001 Standard for Local and Metropolitan Area
Networks: Overview and Architecture", 2002.
[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.
[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,
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September 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, 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.
8.2. Informative References
[RFC3610] Whiting, D., Housley, R., and N. Ferguson, "Counter with
CBC-MAC (CCM)", RFC 3610, September 2003.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic
Host Configuration Protocol (DHCP) version 6", RFC 3633,
December 2003.
[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy
Extensions for Stateless Address Autoconfiguration in
IPv6", RFC 4941, September 2007.
Appendix A. Bluetooth Low Energy fragmentation and L2CAP Modes
This section provides an overview of Fragmentation and Recombination
(FAR) method and L2CAP modes in Bluetooth Low Energy. FAR is an
L2CAP mechanism, in which an L2CAP entity can take the (large) upper
layer PDU, prepend the L2CAP header (4 bytes in the Basic L2CAP mode)
and break the resulting L2CAP PDU into fragments which can then be
directly encapsulated into Data channel PDUs. There are bits in the
Data channel PDUs which identify whether the payload is a complete
L2CAP PDU or the first of a set of fragments, or one of the rest of
the fragments.
There are five L2CAP modes defined in the BT 4.0 spec. These modes
are: Retransmission Mode (a Go-Back-N mechanism is used), Enhanced
Retransmission Mode (includes selective NAK among others), Flow
Control Mode (PDUs are numbered, but there are no retransmissions),
Streaming Mode (PDUs are numbered, but there are no ACKs of any kind)
and Basic L2CAP Mode.
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Authors' Addresses
Johanna Nieminen (editor)
Nokia
Itaemerenkatu 11-13
FI-00180 Helsinki
Finland
Email: johannamaria.nieminen@gmail.com
Teemu Savolainen (editor)
Nokia
Hermiankatu 12 D
FI-33720 Tampere
Finland
Email: teemu.savolainen@nokia.com
Markus Isomaki
Nokia
Keilalahdentie 2-4
FI-02150 Espoo
Finland
Email: markus.isomaki@nokia.com
Basavaraj Patil
6021 Connection drive
Irving, TX 75039
USA
Email: bpatil@ovi.com
Zach Shelby
Sensinode
Hallituskatu 13-17D
FI-90100 Oulu
Finland
Email: zach.shelby@sensinode.com
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Carles Gomez
Universitat Politecnica de Catalunya/i2CAT
C/Esteve Terradas, 7
Castelldefels 08860
Spain
Email: carlesgo@entel.upc.edu
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