6LPWA Static Context Header Compression (SCHC) for IPV6 and UDP
draft-toutain-6lpwa-ipv6-static-context-hc-00
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| Authors | Ana Minaburo , Laurent Toutain | ||
| Last updated | 2016-06-06 | ||
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draft-toutain-6lpwa-ipv6-static-context-hc-00
Network Working Group A. Minaburo
Internet-Draft Acklio
Intended status: Informational L. Toutain
Expires: December 8, 2016 Institut MINES TELECOM ; TELECOM Bretagne
June 6, 2016
6LPWA Static Context Header Compression (SCHC) for IPV6 and UDP
draft-toutain-6lpwa-ipv6-static-context-hc-00
Abstract
This document describes a header compression scheme for IPv6, IPv6/
UDP based on static contexts. This technique is especially tailored
for LPWA networks and could be extended to other protocol stacks.
During the IETF history several compression mechanisms have been
proposed. First mechanisms, such as RoHC, are using a context to
store header field values and send smaller incremental differences on
the link. Values in the context evolve dynamically with information
contained in the compressed header. The challenge is to maintain
sender's and receiver's contexts synchronized even with packet
losses. Based on the fact that IPv6 contains only static fields,
6LoWPAN developed an efficient context-free compression mechanisms,
allowing better flexibility and performance.
The Static Context Header Compression (SCHC) combines the advantages
of RoHC formal notation, which offers a great level of flexibility in
the processing of fields, and 6LoWPAN behavior to elide fields that
are known from the other side. Static context means that values in
the context field do not change during the transmission, avoiding
complex resynchronization mechanisms, incompatible with LPWA
characteristics. In most of the cases, IPv6/UDP/CoAP headers are
reduced to a small context identifier.
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
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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
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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 December 8, 2016.
Copyright Notice
Copyright (c) 2016 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.
1. Introduction
Headers compression is mandatory to bring the internet protocols to
the node within a LPWA network. 6LoWPAN and its evolutions do not
fulfil the drastic constraints imposed by the radio technology
[I-D.minaburo-lp-wan-gap-analysis].
Nevertheless, LPWA networks offer good properties for an efficient
header compression:
o Topology is star oriented. For the needs of this draft, the
architecture can be summarized to End-Systems (ES) exchanging
information with a single LPWA Compressor (LC). In most of the
cases, End Systems and LC form a star topology.
o Traffic flows are mostly deterministic, since End-Systems embed
built-in applications. Contrary to computers or smartphones, new
applications cannot be easily installed.
First mechanisms such as RoHC use a context to store header field
values and send smaller incremental differences on the link. The
first version of RoHC targeted IP/UDP/RTP stack. RoHCv2 extends the
principle to any protocol and introduces a formal notation [RFC4997]
describing the header and associating compression functions to each
field. To be efficient the sender and the receiver must check that
the context remains synchronized (i.e. contains the same values).
Context synchronization imposes to periodically send a full header or
at least dynamic fields. If fully compressed, the header can be
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compatible with LPWA constraints. However, the first exchanges or a
context resynchronisation impose to send uncompressed headers, which
may be bigger than the original one. This will force the use of
inefficient fragmentation mechanisms. For some LPWA technologies,
duty cycle limits can also delay the resynchronization. Figure 1
illustrates this behavior.
sync
^ +-+ sync sync ^
| IPv6 | | +-+ +-+ | IPv6
v | | | | | | v
+------------+ | +-+-+ | | | | +------------+
| +--+ | | | | | | | | | | +--+ |
| | c| | | | | +-+-+-+ +-+-+-+-+ | | | c| |
| | t| | | | | | | | | | | | | | | | | t| |
| | x| | +-+-+-+-+-+-+-+-+-+-+-+-+ | | x| |
| | t| | <----------------------------> | | t| |
| +--+ | | +--+ |
+------------+ +------------+
Figure 1: RoHC Compressed Header size evolution.
On the other hand, 6LoWPAN [RFC4944] is context-free based on the
fact that IPv6, its extensions or UDP headers do not contain
incremental fields. The compression mechanism described in [RFC6282]
is based on sending a 2-byte bitmap, which describe how the header
should be decompressed, either using some standard values or
information sent after this bitmap. [RFC6282] also allows for UDP
compression.
In the best case, when Hop limit is a standard value, flow label,
DiffServ fields are set to 0 and Link Local addresses are used over a
single hop network, the 6LoWPAN compressed header is reduced to 4
bytes. This compression ratio is possible because the IID are
derived from the MAC addresses and the link local prefix is known
from both sides. In that case, the IPv6 compression is 4 bytes and
UDP compression is 2 bytes, which fills half of the payload of a
SIGFOX frame, or more than 10% of a LoRaWAN payload (with spreading
factor 12).
The Static Context Header Compression (SCHC) combines the advantages
of RoHC formal notation, which offers a great level of flexibility in
the processing of fields, and 6LoWPAN behavior to elide fields that
are known from the other side. Static context means that values in
the context field do not change during the transmission, avoiding
complex resynchronization mechanisms, incompatible with LPWA
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characteristics. In most of the cases, IPv6/UDP/CoAP headers are
reduced to a small context identifier.
2. Static Context Header Compression
Static Context Header Compression (SCHC) avoids context
synchronization, which is the most bandwidth-consuming operation in
RoHC. Based on the fact that the nature of data flows is highly
predictable in LPWA networks, a static context may be stored on the
End-System (ES). The other end, the LPWA Compressor (LC) can learn
the context through a provisionning protocol during the
identification phase.
The context contains an ordered lists of rules. Each rule is
identified by a value, also called context identifier. If the layer
2 allows it, the context id can be carried in the layer 2 header.
Otherwise the context id is the first byte of the L2 payload. Being
at the boundary between Layer 2 and Layer 3, the context id is also
called a SHIM. Different ES will use the same SHIM to identify their
own context. An LC needs the ES MAC address to identify the
appropriate context in its memory.
Context rules will be used for several purposes:
o Flow compression: context rules contain a high-level description
of the headers' fields and associate a function to each of them.
o Flow decompression: the function associated to each field
indicates also the decompression behavior.
o Uncompressed flow selection: The information stored in the context
rule is also used to match incoming packets to check if the
compression rule can be applied. There is a strong relation
between filtering and decompression. For instance, a flow may be
defined as a set of values that correspond to a set of fields.
This flow is identified by a SHIM. A destination sharing the same
context is able to reconstruct the original header upon reception
of a given SHIM.
o Compressed flow selection: when receiving a compressed packet,
information in the context (typically the SHIM) will be used to
select the decompression rule in combination with the ES MAC
address.
o Packet filtering: LPWA can be easily subject to DoS attacks. If a
packet is not explicitly assigned to a specific context, then
incoming packets will be discarded.
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3. Filtering functions
The compression/decompression mechanisms proposed in this Figure 2 is
a combinaison of 6LoWPAN principles, which are efficient in sending
only information what cannot be reconstructed at the other end, and
RoHCv2 which assigns compression and decompression functions to each
field. The use of a context avoids sending well-known information.
/--------------------+-----+-----+-------------+--------------------------\
| Function |Selec|Selec| Compression | Decompression |
| |comp |dec. | | |
+--------------------+-----+-----+-------------+--------------------------+
|ignore |no |no |elided |add value stored in ctxt |
|send-value |no |no |send value |build field from value |
|send-value-lbs |yes |no |send lsb |concatenation ctxt val+lsb|
|send-value-filter |no |yes |send value |elided |
|not-sent |yes |no |elided |add value stored in ctxt |
|just-check |yes |yes |nothing |nothing |
|compute-IPv6-length |no |no |elided |compute IPv6 length |
|compute-UDP-length |no |no |elided |compute UDP length |
|compute-UDP-checksum|no |no |elided |compute UDP checksum |
|ESiid-MAC |no |no |elided |build IID from L2 ES addr |
|LAiid-MAC |no |no |elided |build IID from L2 LA addr |
\--------------------+-----+-----+-------------+--------------------------/
Figure 2: Simplified Protocol Stack for LP-WAN
Figure 2 lists all the functions defined to compress and decompress a
field. The first column gives the function's name.
The second column describes the rule selection property of the
function. Selection determines if the compression rule can be
applied to a packet. A comparison is made between the value stored
in the context and the field's value. Generally it is an equality
between the field value and a associated context value, but functions
may define more complex matching rules. To succeed and apply the
compression/decompression rule, the comparisons of all header fields
marked as "yes" in this column must be true.
The third column indicates which function can be used to select the
appropriate rules for decompression. Typically it will be the SHIM
and the MAC address.
Fourth column outlines the compression process.
Last column outlines the decompression process.
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As with 6LoWPAN, the compression process may produce some data, where
fields that were not compressed (or were partially compressed) will
be sent in the order order of the original packet. Information added
by the compression phase must be aligned on byte boundaries, but each
individual compression function may generate any size.
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/--------------------+---------------------+----------------------------------------\
| Field |Function | Behavior |
+--------------------+---------------------+----------------------------------------+
|IPv6 version |ignore |No IPv4: not sent, not used for select |
| |send-value-filter* |With IPv4: sent value, used for select |
+--------------------+---------------------+----------------------------------------+
|IPv6 DiffServ |not-sent* |The value is not sent, but each end |
|IPv6 Flow Label | |agree on a value, which can be someting |
| | |different from 0. |
| |send-value |If DiffServ field varies it is sent |
+--------------------+---------------------+----------------------------------------+
|IPv6 Length |compute-IPv6-length |Dedicated function to reconstruct value |
+--------------------+---------------------+----------------------------------------+
[IPv6 Next Header |not-sent* |Value is known in the ctxt. |
| |send value |Same behavior as 6LoWPAN |
+--------------------+---------------------+----------------------------------------+
|IPv6 Hop Limit |ignore |The receiver will put a value stored in |
| | |the context. It may be different from |
| | |one originally sent, but in s star |
| | |topology, there is not risk of loops |
| |not-sent* |Receiver and sender agree on the value. |
| | |If the value is not correct the packet |
| | |is discarded |
| |send-value |Explicitly sent |
+--------------------+---------------------+----------------------------------------+
|IPv6 ESPrefix |not-sent* |The 64 bit prefix is stored on the ctxt |
|IPv6 LCPrefix |send-value |Explicitly send 64 bits on the link |
+--------------------+---------------------+----------------------------------------+
|IPv6 ESiid |not-sent |IID is not sent, but stored in the ctxt |
|IPv6 LCiid |ESiid-MAC | LCiid-MAC|IID is built from the ES MAC address |
| |send-value* |IID is explicitly sent on the link. The |
| | |size depends of the L2 technology |
+--------------------+---------------------+----------------------------------------+
|UDP ESport |not-sent |In the context |
|UDP LCport |send-value* |Send the 2 bytes of the port number |
| |send-value-lsb* |Send least significant bits of the port |
| | |number. |
+--------------------+---------------------+----------------------------------------+
|UDP length |compute-UDP-length |Dedicated function to reconstruct value |
|UDP Checksum |compute-UDP-checksum |Dedicated function to reconstruct value |
+--------------------+---------------------+----------------------------------------+
* field used for rule selection.
Figure 3: SCHC functions' example assignment for IPv6 and UDP
Figure 3 gives an example of function assignment to IPv6/UDP fields,
a star after the function name indicates when a field participates in
the context id selection.
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3.1. Compression functions
3.1.1. Ignore
Ignore function defines a field that does not participate to the rule
selection process. The field value will not be sent on the wire and
can be reconstructed on the other side.
The ignore function can be assigned to the IPv6 version field (if
IPv4 is not used in the system). IPv6 Hop Limit may also be a
candidate in some cases. Hop Limit value will not affect the flow
selection process. The receiver may assign a static value. If there
is a risk of loop creation (i.e. non-star topology), the send-value
function must be used instead.
3.1.2. Send-value
This function is used to transmit the full field value that is not
stored in the context. In the decompression phase, the receiver uses
the transmitted value for reconstructing the field. This field
cannot participate to the selection process since it can vary other
the time.
The send-value function may be used to send interface IID in a meshed
topology.
3.1.3. Send-value-lsb
This function allows to send only the less significant bits of a
value. The context contains the size of the less significant bits
and a reference value.
Send-value-lbs is involved in the rule selection. The most
significant bit of field's value must matches the most significant
bits of the context reference value.
The sender send on the radio link only the less significant bits.
The receiver reconstruct the initial value by concatenating the most
significant bits of reference value contained in the context and the
less significant bits received.
This function can be used to define a port range and allow several IP
flows to share the same context.
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3.1.4. Send-value-filter
In the compression phase, a field assigned with this value is sent on
the radio link. It does not influence the rule selection.
Value sent on the link influences the rule selection for
decompression.
Typically, this function is used to transmit the SHIM field and
proceed to rule identification when the header is decompressed. The
SHIM is elided from the uncompressed header.
3.1.5. Not-sent
In the compression phase, a field assigned with this value is not
sent on the radio link. This influence the rule selection.
In the decompression phase, the uncompressed value is the one stored
in the context. Since the value is not send on the radio link, it
cannot influence the flow selection.
IPv6 protocol identifier, UDP ports number fields can be assigned to
this function. This avoid to send then on the link.
3.1.6. just-check
The field value is checked for the rule selection, but nothing is
sent on the radio link.
This can be used to include L2 parameters such as addresses in the
rule selection.
3.1.7. compute-IPv6-lenght, compute-UDP-length, compute-UDP-checksum
Fields assigned with this functions are not sent on the radio link,
they do not participate to the rule selection process. They are
computed during the decompression phase.
This functions are specific to a field in the header.
3.1.8. ESiid-MAC, LCiid-MAC
These functions are used to process respectively the End System and
the LPWA AP Interface Identifier. The IID value is computed from
addresses present in the MAC header. The computation depends of the
technology and the MAC address size. The values of the field do not
participate to the flow selection since they are sent on the radio
link at layer 2.
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These functions can be used in case of the star topology.
4. Examples
This section gives some scenarios of the compression mechanism. Note
that for reasons of simplicity in this example CoAP is not
compressed, it will be described later with the same principles. The
goal is to illustrate the SCHC behaviour.
4.1. IPv6/UDP compression in a star topology
The most common case will be a LPWA end-system embeds some
applications running over CoAP. Typically one will be for the device
management using the COMI/CoOL protocol (using UDP ports 123 and
124). The second one will be a CoAP server for measurements done by
the end-system (using ports 5683). A third UDP traffic is for legacy
applications using different ports numbers. Figure 4 presents the
protocol stack for this end-system. IPv6 and UDP are represented
with dotted lines since these protocols are compressed on the radio
link. The context ID is represented by a SHIM (respectively 0, 1 and
2).
|
|/c |/a |
+----------+---------+---------+
| CoAP | CoAP | legacy |
+----||----+---||----+---||----+
. UDP . UDP | UDP |
................................
. IPv6 . IPv6 . IPv6 .
+--SHIM0------SHIM1-----SHIM2---------------------------+
| 6LPWA L2 technologies |
+-------------------------------------------------------+
End System or LPWA GW
Figure 4: Simplified Protocol Stack for LP-WAN
Note that in some LPWA technologies, only End Systems have a MAC
address. Therefore it is necessary to define an IID for the Link
Local address for the LPWA Compressor.
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 0 | 0 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
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|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent | FE80::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent | FE80::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | not-sent | 123 | |
|UDP LCport | not-sent | 124 | |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 1 | 1 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent | FE80::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent | FE80::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | not-sent | 5683 | |
|UDP LCport | not-sent | 5683 | |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 2 | 2 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
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|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent | FE80::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent | FE80::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | send-value | | port number |
|UDP LCport | send-value | | port number |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
Figure 5: Simplified Protocol Stack for LP-WAN
Figure 6 shows an alternative way to compress more efficiently port
numbers. The send-value-lsb allows to send in one byte the two ports
number differences. Since the compressed information must be aligned
on byte boundary, it has been chosen in the example a size of 4 bits
for each lsb.
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 2 | 2 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent | FE80::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent | FE80::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | send-value-lsb | 4+ES ref val | lsb |
|UDP LCport | send-value-lsb | 4+LC ref val | lsb |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
Figure 6: Alternative compressions of port numbers
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4.2. Global addresses
The scenario depicted Figure 7, management remains with Link Local
addresses, but the CoAP message are sent to an external server
2001:db8:1::1 and the legacy to another server 2001:db8:2::1/64. The
EC must be configured with the prefix used by the LC to forward
traffic. This prefix could be changed using a management procedure
if needed.
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 0 | 0 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent | FE80::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent | FE80::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | not-sent | 123 | |
|UDP LCport | not-sent | 124 | |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 1 | 1 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent |2001:db8:3::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent |2001:bd8:1::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | not-sent | 5683 | |
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|UDP LCport | not-sent | 5683 | |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
+----------------+------------------------+----------------+-----------------+
| Field | Function | Ctxt Value | Sent compressed |
+----------------+------------------------+----------------+-----------------+
| LPWA SHIM | send-value-filter | 2 | 2 |
+================+========================+================+=================+
|IPv6 version | ignore | | |
|IPv6 DiffServ | not-sent | 0 | |
|IPv6 Flow Label | not-sent | 0 | |
|IPv6 Length | compute-IPv6-length |----------------| |
|IPv6 Next Header| not-sent | 17 | |
|IPv6 Hop Limit | ignore | 1 | |
|IPv6 ESprefix | not-sent |2001:db8:3::/64 | |
|IPv6 ESiid | ESiid-MAC | | |
|IPv6 LCprefix | not-sent |2001:db8:2::/64 | |
|IPv6 LCiid | LCiid-value | ::1 | |
+================+========================+================+=================+
|UDP ESport | send-value | | port number |
|UDP LCport | send-value | | port number |
|UDP Length | compute-UDP-length |----------------| |
|UDP checksum | compute-UDP-checksum |----------------| |
+================+========================+================+=================+
Figure 7: Compression with global addresses
5. CoAP compression
TBD
6. Normative References
[I-D.minaburo-lp-wan-gap-analysis]
Minaburo, A., Pelov, A., and L. Toutain, "LP-WAN GAP
Analysis", draft-minaburo-lp-wan-gap-analysis-01 (work in
progress), February 2016.
[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, DOI 10.17487/RFC4944, September 2007,
<http://www.rfc-editor.org/info/rfc4944>.
Minaburo & Toutain Expires December 8, 2016 [Page 14]
Internet-Draf6LPWA Static Context Header Compression (SCHC) June 2016
[RFC4997] Finking, R. and G. Pelletier, "Formal Notation for RObust
Header Compression (ROHC-FN)", RFC 4997,
DOI 10.17487/RFC4997, July 2007,
<http://www.rfc-editor.org/info/rfc4997>.
[RFC6282] Hui, J., Ed. and P. Thubert, "Compression Format for IPv6
Datagrams over IEEE 802.15.4-Based Networks", RFC 6282,
DOI 10.17487/RFC6282, September 2011,
<http://www.rfc-editor.org/info/rfc6282>.
Authors' Addresses
Ana Minaburo
Acklio
2bis rue de la Chataigneraie
35510 Cesson-Sevigne Cedex
France
Email: ana@ackl.io
Laurent Toutain
Institut MINES TELECOM ; TELECOM Bretagne
2 rue de la Chataigneraie
CS 17607
35576 Cesson-Sevigne Cedex
France
Email: Laurent.Toutain@telecom-bretagne.eu
Minaburo & Toutain Expires December 8, 2016 [Page 15]