< draft-ietf-roll-dao-projection-05.txt   draft-ietf-roll-dao-projection-06.txt >
ROLL P. Thubert, Ed. ROLL P. Thubert, Ed.
Internet-Draft Cisco Systems Internet-Draft Cisco Systems
Intended status: Standards Track R. Jadhav Updates: 6550, 6553, 8138 (if approved) R. Jadhav
Expires: June 24, 2019 Huawei Tech Intended status: Standards Track Huawei Tech
M. Gillmore Expires: November 25, 2019 M. Gillmore
Itron Itron
J. Pylakutty J. Pylakutty
Cisco Cisco
December 21, 2018 May 24, 2019
Root initiated routing state in RPL Root initiated routing state in RPL
draft-ietf-roll-dao-projection-05 draft-ietf-roll-dao-projection-06
Abstract Abstract
This document proposes a protocol extension to RPL that enables to This document extends RFC 6550, RFC 6553 and RFC 8138 and enable to
install a limited amount of centrally-computed routes in a RPL graph, install a limited amount of centrally-computed routes in a RPL graph,
enabling loose source routing down a non-storing mode DODAG, or enabling loose source routing down a non-storing mode DODAG, or
transversal routes inside the DODAG. As opposed to the classical transversal routes inside the DODAG. In constrast with classical
route injection in RPL that are injected by the end devices, this routes in RPL that are injected by the end devices, this draft
draft enables the root of the DODAG to projects the routes that are enables the root of the DODAG to projects the routes that are needed
needed on the nodes where they should be installed. on the nodes where they should be installed.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 24, 2019. This Internet-Draft will expire on November 25, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. BCP 14 . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. BCP 14 . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Subset of a 6LoWPAN Glossary . . . . . . . . . . . . . . 4 2.2. New Terms . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3. New Terms . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3. References . . . . . . . . . . . . . . . . . . . . . . . 4
2.4. References . . . . . . . . . . . . . . . . . . . . . . . 5 3. Extending RFC 6550 . . . . . . . . . . . . . . . . . . . . . 4
3. Extending RFC 6550 . . . . . . . . . . . . . . . . . . . . . 5
3.1. RPL Instances . . . . . . . . . . . . . . . . . . . . . . 5 3.1. RPL Instances . . . . . . . . . . . . . . . . . . . . . . 5
3.2. New RPL Control Message Options . . . . . . . . . . . . . 6 3.2. New RPL Control Message Options . . . . . . . . . . . . . 5
3.3. Projected DAO . . . . . . . . . . . . . . . . . . . . . . 7 3.3. RPI for Projected Routes . . . . . . . . . . . . . . . . 7
3.3.1. Non-Storing Mode P-Route . . . . . . . . . . . . . . 8 3.4. Projected DAO . . . . . . . . . . . . . . . . . . . . . . 7
3.3.2. Storing-Mode P-Route . . . . . . . . . . . . . . . . 10 3.4.1. Non-Storing Mode P-Route . . . . . . . . . . . . . . 9
4. Security Considerations . . . . . . . . . . . . . . . . . . . 12 3.4.2. Storing-Mode P-Route . . . . . . . . . . . . . . . . 10
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 4. Extending RFC 8138 . . . . . . . . . . . . . . . . . . . . . 13
5.1. New RPL Control Codes . . . . . . . . . . . . . . . . . . 12 4.1. Elective RPI 6LoRH . . . . . . . . . . . . . . . . . . . 13
5.2. Error in Projected Route ICMPv6 Code . . . . . . . . . . 13 5. Extending RFC 6553 . . . . . . . . . . . . . . . . . . . . . 13
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 5.1. Uncompressed RPL Option . . . . . . . . . . . . . . . . . 13
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 6. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . 14 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . 15 7.1. New Elective 6LoWPAN Routing Header Type . . . . . . . . 14
Appendix A. Applications . . . . . . . . . . . . . . . . . . . . 15 7.2. New RPL Control Codes . . . . . . . . . . . . . . . . . . 15
A.1. Loose Source Routing in Non-storing Mode . . . . . . . . 15 7.3. Error in Projected Route ICMPv6 Code . . . . . . . . . . 15
A.2. Transversal Routes in storing and non-storing modes . . . 17 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
Appendix B. Examples . . . . . . . . . . . . . . . . . . . . . . 19 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
B.1. Using storing mode P-DAO in non-storing mode MOP . . . . 19 9.1. Normative References . . . . . . . . . . . . . . . . . . 16
B.2. Projecting a storing-mode transversal route . . . . . . . 20 9.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 Appendix A. Applications . . . . . . . . . . . . . . . . . . . . 18
A.1. Loose Source Routing in Non-storing Mode . . . . . . . . 18
A.2. Transversal Routes in storing and non-storing modes . . . 19
Appendix B. Examples . . . . . . . . . . . . . . . . . . . . . . 21
B.1. Using storing mode P-DAO in non-storing mode MOP . . . . 21
B.2. Projecting a storing-mode transversal route . . . . . . . 22
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 24
1. Introduction 1. Introduction
The "Routing Protocol for Low Power and Lossy Networks" [RFC6550] The "Routing Protocol for Low Power and Lossy Networks" [RFC6550]
(LLN)(RPL) is a generic Distance Vector protocol that is well suited (LLN)(RPL) is a generic Distance Vector protocol that is well suited
low energy Internet of Things (IoT) networks. RPL forms Destination low energy Internet of Things (IoT) networks. RPL forms Destination
Oriented Directed Acyclic Graphs (DODAGs) in which the root often Oriented Directed Acyclic Graphs (DODAGs) in which the root often
acts as the Border Router to connect the RPL domain to the Internet. acts as the Border Router to connect the RPL domain to the Internet.
The root is responsible to select the RPL Instance that is used to The root is responsible to select the RPL Instance that is used to
forward a packet coming from the Internet into the RPL domain and set forward a packet coming from the Internet into the RPL domain and set
skipping to change at page 4, line 5 skipping to change at page 4, line 15
2. Terminology 2. Terminology
2.1. BCP 14 2.1. BCP 14
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119][RFC8174] when, and only when, they appear in all 14 [RFC2119][RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2.2. Subset of a 6LoWPAN Glossary 2.2. New Terms
This document often uses the following acronyms:
6BBR: 6LoWPAN Backbone Router
6LBR: 6LoWPAN Border Router
6LN: 6LoWPAN Node
6LR: 6LoWPAN Router
6CIO: Capability Indication Option
EARO: (Extended) Address Registration Option -- (E)ARO
EDAR: (Extended) Duplicate Address Request -- (E)DAR
EDAC: (Extended) Duplicate Address Confirmation -- (E)DAC
DAD: Duplicate Address Detection
DODAG: Destination-Oriented Directed Acyclic Graph
LLN: Low-Power and Lossy Network
NA: Neighbor Advertisement
NCE: Neighbor Cache Entry
ND: Neighbor Discovery
NDP: Neighbor Discovery Protocol
NS: Neighbor Solicitation
RPL: IPv6 Routing Protocol for LLNs (pronounced ripple) [RFC6550]
RA: Router Advertisement
RS: Router Solicitation
2.3. New Terms
P-Route: A route that is installed remotely by a RPL root. P-Route: A route that is installed remotely by a RPL root.
2.4. References 2.3. References
In this document, readers will encounter terms and concepts that are In this document, readers will encounter terms and concepts that are
discussed in the following documents: discussed in the following documents:
o "Routing Protocol for Low Power and Lossy Networks" [RFC6550], and o "Routing Protocol for Low Power and Lossy Networks" [RFC6550], and
o "Terminology in Low power And Lossy Networks" [RFC7102]. o "Terminology in Low power And Lossy Networks" [RFC7102].
3. Extending RFC 6550 3. Extending RFC 6550
skipping to change at page 7, line 32 skipping to change at page 7, line 15
a No-Path (for that Target) in this document. a No-Path (for that Target) in this document.
Via Address: 16 bytes. IPv6 Address of the next hop towards the Via Address: 16 bytes. IPv6 Address of the next hop towards the
destination(s) indicated in the target option that immediately destination(s) indicated in the target option that immediately
precede the RPO. Via Addresses are indicated in the order of precede the RPO. Via Addresses are indicated in the order of
the data path from the ingress to the egress nodes. the data path from the ingress to the egress nodes.
An RPO MUST contain at least one Via Address, and a Via Address MUST An RPO MUST contain at least one Via Address, and a Via Address MUST
NOT be present more than once, otherwise the RPO MUST be ignored. NOT be present more than once, otherwise the RPO MUST be ignored.
3.3. Projected DAO 3.3. RPI for Projected Routes
RPL [RFC6550], Section 11.2, specifies the RPL Packet Information
(RPI) as a set of fields that are placed by RPL routers in IP packets
to identify the RPL Instance, detect anomalies and trigger corrective
actions.
In particular, the SenderRank, which is the scalar metric computed by
a specialized Objective Function such as described in [RFC6552],
indicates the Rank of the sender and is modified at each hop. The
SenderRank field is used to validate that the packet progresses in
the expected direction, either upwards or downwards, along the DODAG.
RPL defines the "RPL Option for Carrying RPL Information in Data-
Plane Datagrams" [RFC6553] to transport the RPI, which is carried in
an IPv6 Hop-by-Hop Options Header [RFC8200], typically consuming
eight bytes per packet.
This specification updates [RFC6550] as follows. When using
projected routes, the Rank is useless and SHOULD be set to 0 in the
non-compressed form, and can be elided in the compressed form (see
Section 4.1). In a same fashion, the O, R, and F flags that are
defined in Section 11.2 of [RFC6550] are not used for packets that
follow a projected route and they MUST be reset. A new flag is
added, the P flag that indicates that the packet is injected along a
projected route.
3.4. Projected DAO
This draft adds a capability to RPL whereby the root of a DODAG This draft adds a capability to RPL whereby the root of a DODAG
projects a route by sending an extended DAO message called a projects a route by sending an extended DAO message called a
Projected-DAO (P-DAO) to an arbitrary router in the DODAG, indicating Projected-DAO (P-DAO) to an arbitrary router in the DODAG, indicating
one or more sequence(s) of routers inside the DODAG via which the one or more sequence(s) of routers inside the DODAG via which the
target(s) indicated in the Target Information Option(s) (TIO) can be target(s) indicated in the Target Information Option(s) (TIO) can be
reached. reached.
A P-DAO is sent from a global address of the root to a global address A P-DAO is sent from a global address of the root to a global address
of the recipient, and MUST be confirmed by a DAO-ACK, which is sent of the recipient, and MUST be confirmed by a DAO-ACK, which is sent
skipping to change at page 8, line 10 skipping to change at page 8, line 22
Like a classical DAO message, a P-DAO is processed only if it is Like a classical DAO message, a P-DAO is processed only if it is
"new" per section 9.2.2. "Generation of DAO Messages" of the RPL "new" per section 9.2.2. "Generation of DAO Messages" of the RPL
specification [RFC6550]; this is determined using the Path Sequence specification [RFC6550]; this is determined using the Path Sequence
information from the RPO as opposed to a TIO. Also, a Path Lifetime information from the RPO as opposed to a TIO. Also, a Path Lifetime
of 0 in an RPO indicates that a route is to be removed. of 0 in an RPO indicates that a route is to be removed.
There are two kinds of operation for the P-Routes, the Storing Mode There are two kinds of operation for the P-Routes, the Storing Mode
and the Non-Storing Mode. and the Non-Storing Mode.
o The Non-Storing Mode is discussed in Section 3.3.1. It uses an o The Non-Storing Mode is discussed in Section 3.4.1. It uses an
SRVIO that carries a list of Via Addresses to be used as a source- SRVIO that carries a list of Via Addresses to be used as a source-
routed path to the target. The recipient of the P-DAO is the routed path to the target. The recipient of the P-DAO is the
ingress router of the source-routed path. Upon a Non-Storing Mode ingress router of the source-routed path. Upon a Non-Storing Mode
P-DAO, the ingress router installs a source-routed state to the P-DAO, the ingress router installs a source-routed state to the
target and replies to the root directly with a DAO-ACK message. target and replies to the root directly with a DAO-ACK message.
o The Storing Mode is discussed in Section 3.3.2. It uses a VIO o The Storing Mode is discussed in Section 3.4.2. It uses a VIO
with one Via Address per consecutive hop, from the ingress to the with one Via Address per consecutive hop, from the ingress to the
egress of the path, including the list of all intermediate routers egress of the path, including the list of all intermediate routers
in the data path order. The Via Addresses indicate the routers in in the data path order. The Via Addresses indicate the routers in
which the routing state to the target have to be installed via the which the routing state to the target have to be installed via the
next Via Address in the VIO. In normal operations, the P-DAO is next Via Address in the VIO. In normal operations, the P-DAO is
propagated along the chain of Via Routers from the egress router propagated along the chain of Via Routers from the egress router
of the path till the ingress one, which confirms the installation of the path till the ingress one, which confirms the installation
to the root with a DAO-ACK message. Note that the root may be the to the root with a DAO-ACK message. Note that the root may be the
ingress and it may be the egress of the path, that it can also be ingress and it may be the egress of the path, that it can also be
neither but it cannot be both. neither but it cannot be both.
In case of a forwarding error along a P-Route, an ICMP error is sent In case of a forwarding error along a P-Route, an ICMP error is sent
to the root with a new Code "Error in Projected Route" (See to the root with a new Code "Error in Projected Route" (See
Section 5.2). The root can then modify or remove the P-Route. The Section 7.3). The root can then modify or remove the P-Route. The
"Error in Projected Route" message has the same format as the "Error in Projected Route" message has the same format as the
"Destination Unreachable Message", as specified in RFC 4443 "Destination Unreachable Message", as specified in RFC 4443
[RFC4443]. The portion of the invoking packet that is sent back in [RFC4443]. The portion of the invoking packet that is sent back in
the ICMP message SHOULD record at least up to the routing header if the ICMP message SHOULD record at least up to the routing header if
one is present, and the routing header SHOULD be consumed by this one is present, and the routing header SHOULD be consumed by this
node so that the destination in the IPv6 header is the next hop that node so that the destination in the IPv6 header is the next hop that
this node could not reach. if a 6LoWPAN Routing Header (6LoRH) this node could not reach. if a 6LoWPAN Routing Header (6LoRH)
[RFC8138] is used to carry the IPv6 routing information in the outter [RFC8138] is used to carry the IPv6 routing information in the outter
header then that whole 6LoRH information SHOULD be present in the header then that whole 6LoRH information SHOULD be present in the
ICMP message. The sender and exact operation depend on the Mode and ICMP message. The sender and exact operation depend on the Mode and
is described in Section 3.3.1 and Section 3.3.2 respectively. is described in Section 3.4.1 and Section 3.4.2 respectively.
3.3.1. Non-Storing Mode P-Route 3.4.1. Non-Storing Mode P-Route
As illustrated in Figure 2, a P-DAO that carries an SRVIO enables the As illustrated in Figure 2, a P-DAO that carries an SRVIO enables the
root to install a source-routed path towards a target in any root to install a source-routed path towards a target in any
particular router; with this path information the router can add a particular router; with this path information the router can add a
source routed header reflecting the P-route to any packet for which source routed header reflecting the P-route to any packet for which
the current destination either is the said target or can be reached the current destination either is the said target or can be reached
via the target. via the target.
------+--------- ------+---------
| Internet | Internet
skipping to change at page 10, line 13 skipping to change at page 10, line 25
Addresses and then the target. Addresses and then the target.
In practice, the router will normally use the "IPv6 over Low-Power In practice, the router will normally use the "IPv6 over Low-Power
Wireless Personal Area Network (6LoWPAN) Paging Dispatch" [RFC8025] Wireless Personal Area Network (6LoWPAN) Paging Dispatch" [RFC8025]
to compress the RPL artifacts as indicated in the "6LoWPAN Routing to compress the RPL artifacts as indicated in the "6LoWPAN Routing
Header" [RFC8138] specification. In that case, the router indicates Header" [RFC8138] specification. In that case, the router indicates
self as encapsulator in an IP-in-IP 6LoRH Header, and places the list self as encapsulator in an IP-in-IP 6LoRH Header, and places the list
of Via Addresses in the order of the VIO and then the target in the of Via Addresses in the order of the VIO and then the target in the
SRH 6LoRH Header. SRH 6LoRH Header.
+-+ ... -+-+ ... +-+- ... -+-+- ... -+-+-+- ... -+-+ ...
|11110001|SRH-6LoRH| ERPI- | IP-in-IP Encap | NH=1 |11110CPP|
|Page 1 |Type1 S=2| 6LoRH | 6LoRH sulator |LOWPAN_IPHC| UDP |
+-+ ... -+-+ ... +-+- ... -+-+- ... -+-+-+- ... -+-+ ...
<-RFC8138-><-This-><----RFC 8138----><-----RFC 6282------->
RFC 5 to 19 bytes No RPL artifact
Figure 3: Example Compressed Packet with SRH.
In case of a forwarding error along a Source Route path, the node In case of a forwarding error along a Source Route path, the node
that fails to forward SHOULD send an ICMP error with a code "Error in that fails to forward SHOULD send an ICMP error with a code "Error in
Source Routing Header" back to the source of the packet, as described Source Routing Header" back to the source of the packet, as described
in section 11.2.2.3. of [RFC6550]. Upon this message, the in section 11.2.2.3. of [RFC6550]. Upon this message, the
encapsulating node SHOULD stop using the source route path for a encapsulating node SHOULD stop using the source route path for a
period of time and it SHOULD send an ICMP message with a Code "Error period of time and it SHOULD send an ICMP message with a Code "Error
in Projected Route" to the root. Failure to follow these steps may in Projected Route" to the root. Failure to follow these steps may
result in packet loss and wasted resources along the source route result in packet loss and wasted resources along the source route
path that is broken. path that is broken.
3.3.2. Storing-Mode P-Route 3.4.2. Storing-Mode P-Route
As illustrated in Figure 3, the Storing Mode projected iq used by the As illustrated in Figure 4, the Storing Mode projected iq used by the
root to install a routing state towards a target in the routers along root to install a routing state towards a target in the routers along
a segment between an ingress and an egress router; this enables the a segment between an ingress and an egress router; this enables the
routers to forward along that segment any packet for which the next routers to forward along that segment any packet for which the next
loose hop is the said target, for instance a loose source routed loose hop is the said target, for instance a loose source routed
packet for which the next loose hop is the target, or a packet for packet for which the next loose hop is the target, or a packet for
which the router has a routing state to the final destination via the which the router has a routing state to the final destination via the
target. target.
------+--------- ------+---------
| Internet | Internet
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| | DAO | ACK | | | DAO | ACK |
o o o o | | | o o o o | | |
o o o o o o o o o | ^ | Projected . o o o o o o o o o | ^ | Projected .
o o o o o o o o o o | | DAO | Route . o o o o o o o o o o | | DAO | Route .
o o o o o o o o o | ^ | . o o o o o o o o o | ^ | .
o o o o o o o o v | DAO v . o o o o o o o o v | DAO v .
o o LLN o o o | o o LLN o o o |
o o o o o Loose Source Route Path | o o o o o Loose Source Route Path |
o o o o From Root To Destination v o o o o From Root To Destination v
Figure 3: Projecting a route Figure 4: Projecting a route
In order to install the relevant routing state along the segment In order to install the relevant routing state along the segment
between an ingress and an egress routers, the root sends a unicast between an ingress and an egress routers, the root sends a unicast
P-DAO message to the egress router of the routing segment that must P-DAO message to the egress router of the routing segment that must
be installed. The P-DAO message contains the ordered list of hops be installed. The P-DAO message contains the ordered list of hops
along the segment as a direct sequence of Via Information options along the segment as a direct sequence of Via Information options
that are preceded by one or more RPL Target options to which they that are preceded by one or more RPL Target options to which they
relate. Each Via Information option contains a Path Lifetime for relate. Each Via Information option contains a Path Lifetime for
which the state is to be maintained. which the state is to be maintained.
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the state. The P-DAO is forwarded as described above, but the DAO is the state. The P-DAO is forwarded as described above, but the DAO is
interpreted as a No-Path DAO and results in cleaning up existing interpreted as a No-Path DAO and results in cleaning up existing
state as opposed to refreshing an existing one or installing a new state as opposed to refreshing an existing one or installing a new
one. one.
In case of a forwarding error along a Storing Mode P-Route, the node In case of a forwarding error along a Storing Mode P-Route, the node
that fails to forward SHOULD send an ICMP error with a code "Error in that fails to forward SHOULD send an ICMP error with a code "Error in
Projected Route" to the root. Failure to do so may result in packet Projected Route" to the root. Failure to do so may result in packet
loss and wasted resources along the P-Route that is broken. loss and wasted resources along the P-Route that is broken.
4. Security Considerations 4. Extending RFC 8138
4.1. Elective RPI 6LoRH
[RFC8138] defines a Critical 6LoRH to compress the RPL RPI found in
normal packets inside a RPL domain, the RPI-6LoRH.
this specification introduces the ERPI-6LoRH header that MUST be used
to compress the RPI in packets that follow a projected route. As
discussed in Section 3.3, the Rank and the O, R, anf F flags are
always set to 0 and can be elided. The new P flag is always set and
can also be elided. It results that in general only the RPL
InstanceID is necessary in the compressed form.
This specification adds an optimization whereby the local
RPLInstanceID 0 for the source of the packet (the encapsulator when
using IP in IP) can be elided. This is the case where the
RPLInstanceID is encoded as binary b10000000, decimal 128, in the
non-compressed form.
The ERPI-6LoRH header is Elective since it does not contain
information that is critical to the routing and it can be ignored
when not understood. The resulting format is illustrated in Figure 5
below:
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|0|1| Length | 6LoRH Type 5 | RPLInstanceID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: A ERPI-6LoRH carrying a RPLInstanceID
The ERPI-6LoRH header is identifies by a 6LoRH Type of 5 (to be
confirmed by IANA), which is the same value as the RPI-6LoRH but in
the Elective namespace.If the RPLInstanceID is a local RPLInstanceID
0 for the source of the packet then it MUST be elided and the length
MUST be set to 0. Else the length MUST be set to 1 to indicate that
the ERPI-6LoRH carries a RPLinstanceID.
5. Extending RFC 6553
5.1. Uncompressed RPL Option
[RFC6553] defines a format for the RPI that is suitable for
transporting in the IPv6 Hop-by-Hop Header [RFC8200]. This
specification introduces a new flag in the RPI that must be encoded
in any format includeing uncompressed.
The updated format for the RPL Option is presented in Figure 6.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Opt Data Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|O|R|F|P|0|0|0|0| RPLInstanceID | SenderRank |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| (sub-TLVs) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: RPL Option
New fields:
P: 1-bit flag; indicates that the packet is routed along
a projected route.
6. Security Considerations
This draft uses messages that are already present in RPL [RFC6550] This draft uses messages that are already present in RPL [RFC6550]
with optional secured versions. The same secured versions may be with optional secured versions. The same secured versions may be
used with this draft, and whatever security is deployed for a given used with this draft, and whatever security is deployed for a given
network also applies to the flows in this draft. network also applies to the flows in this draft.
TODO: should probably consider how P-DAO messages could be abused by TODO: should probably consider how P-DAO messages could be abused by
a) rogue nodes b) via replay of messages c) if use of P-DAO messages a) rogue nodes b) via replay of messages c) if use of P-DAO messages
could in fact deal with any threats? could in fact deal with any threats?
5. IANA Considerations 7. IANA Considerations
5.1. New RPL Control Codes 7.1. New Elective 6LoWPAN Routing Header Type
This specification assigns a new value (to be confirmed by IANA) in
the Elective 6LoWPAN Routing Header Type Registry created for RFC
8138 as below:
+---------------+-------------+----------------+
| Value | Meaning | Defining Spec |
+---------------+-------------+----------------+
| 5 (suggested) | ERPI-6LoRH | This document |
+---------------+-------------+----------------+
Table 1: New Elective 6LoWPAN Routing Header Type
7.2. New RPL Control Codes
This document extends the IANA registry created by RFC 6550 for RPL This document extends the IANA registry created by RFC 6550 for RPL
Control Codes as follows: Control Codes as follows:
+------+-------------------+---------------+ +------+-------------------+---------------+
| Code | Description | Reference | | Code | Description | Reference |
+------+-------------------+---------------+ +------+-------------------+---------------+
| 0x0A | Via | This document | | 0x0A | Via | This document |
| | | | | | | |
| 0x0B | Source-Routed Via | This document | | 0x0B | Source-Routed Via | This document |
skipping to change at page 13, line 30 skipping to change at page 15, line 43
+-----------+----------------------------------------+--------------+ +-----------+----------------------------------------+--------------+
| 5 | Non-Storing mode of operation with | This | | 5 | Non-Storing mode of operation with | This |
| | P-Routes | document | | | P-Routes | document |
| | | | | | | |
| 6 | Storing mode of operation with | This | | 6 | Storing mode of operation with | This |
| | P-Routes | document | | | P-Routes | document |
+-----------+----------------------------------------+--------------+ +-----------+----------------------------------------+--------------+
DIO Mode of operation DIO Mode of operation
5.2. Error in Projected Route ICMPv6 Code 7.3. Error in Projected Route ICMPv6 Code
In some cases RPL will return an ICMPv6 error message when a message In some cases RPL will return an ICMPv6 error message when a message
cannot be forwarded along a P-Route. This ICMPv6 error message is cannot be forwarded along a P-Route. This ICMPv6 error message is
"Error in Projected Route". "Error in Projected Route".
IANA has defined an ICMPv6 "Code" Fields Registry for ICMPv6 Message IANA has defined an ICMPv6 "Code" Fields Registry for ICMPv6 Message
Types. ICMPv6 Message Type 1 describes "Destination Unreachable" Types. ICMPv6 Message Type 1 describes "Destination Unreachable"
codes. This specification requires that a new code is allocated from codes. This specification requires that a new code is allocated from
the ICMPv6 Code Fields Registry for ICMPv6 Message Type 1, for "Error the ICMPv6 Code Fields Registry for ICMPv6 Message Type 1, for "Error
in Projected Route", with a suggested code value of 8, to be in Projected Route", with a suggested code value of 8, to be
confirmed by IANA. confirmed by IANA.
6. Acknowledgments 8. Acknowledgments
The authors wish to acknowledge JP Vasseur and Patrick Wetterwald for The authors wish to acknowledge JP Vasseur and Patrick Wetterwald for
their contributions to the ideas developed here. their contributions to the ideas developed here.
7. References 9. References
7.1. Normative References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet [RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", STD 89, Protocol Version 6 (IPv6) Specification", STD 89,
RFC 4443, DOI 10.17487/RFC4443, March 2006, RFC 4443, DOI 10.17487/RFC4443, March 2006,
<https://www.rfc-editor.org/info/rfc4443>. <https://www.rfc-editor.org/info/rfc4443>.
[RFC6550] Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J., [RFC6550] Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J.,
Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur, Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur,
JP., and R. Alexander, "RPL: IPv6 Routing Protocol for JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
Low-Power and Lossy Networks", RFC 6550, Low-Power and Lossy Networks", RFC 6550,
DOI 10.17487/RFC6550, March 2012, DOI 10.17487/RFC6550, March 2012,
<https://www.rfc-editor.org/info/rfc6550>. <https://www.rfc-editor.org/info/rfc6550>.
[RFC6552] Thubert, P., Ed., "Objective Function Zero for the Routing
Protocol for Low-Power and Lossy Networks (RPL)",
RFC 6552, DOI 10.17487/RFC6552, March 2012,
<https://www.rfc-editor.org/info/rfc6552>.
[RFC6553] Hui, J. and JP. Vasseur, "The Routing Protocol for Low- [RFC6553] Hui, J. and JP. Vasseur, "The Routing Protocol for Low-
Power and Lossy Networks (RPL) Option for Carrying RPL Power and Lossy Networks (RPL) Option for Carrying RPL
Information in Data-Plane Datagrams", RFC 6553, Information in Data-Plane Datagrams", RFC 6553,
DOI 10.17487/RFC6553, March 2012, DOI 10.17487/RFC6553, March 2012,
<https://www.rfc-editor.org/info/rfc6553>. <https://www.rfc-editor.org/info/rfc6553>.
[RFC6554] Hui, J., Vasseur, JP., Culler, D., and V. Manral, "An IPv6 [RFC6554] Hui, J., Vasseur, JP., Culler, D., and V. Manral, "An IPv6
Routing Header for Source Routes with the Routing Protocol Routing Header for Source Routes with the Routing Protocol
for Low-Power and Lossy Networks (RPL)", RFC 6554, for Low-Power and Lossy Networks (RPL)", RFC 6554,
DOI 10.17487/RFC6554, March 2012, DOI 10.17487/RFC6554, March 2012,
skipping to change at page 15, line 5 skipping to change at page 17, line 19
[RFC8138] Thubert, P., Ed., Bormann, C., Toutain, L., and R. Cragie, [RFC8138] Thubert, P., Ed., Bormann, C., Toutain, L., and R. Cragie,
"IPv6 over Low-Power Wireless Personal Area Network "IPv6 over Low-Power Wireless Personal Area Network
(6LoWPAN) Routing Header", RFC 8138, DOI 10.17487/RFC8138, (6LoWPAN) Routing Header", RFC 8138, DOI 10.17487/RFC8138,
April 2017, <https://www.rfc-editor.org/info/rfc8138>. April 2017, <https://www.rfc-editor.org/info/rfc8138>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
7.2. Informative References [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
9.2. Informative References
[I-D.ietf-6tisch-architecture] [I-D.ietf-6tisch-architecture]
Thubert, P., "An Architecture for IPv6 over the TSCH mode Thubert, P., "An Architecture for IPv6 over the TSCH mode
of IEEE 802.15.4", draft-ietf-6tisch-architecture-19 (work of IEEE 802.15.4", draft-ietf-6tisch-architecture-20 (work
in progress), December 2018. in progress), March 2019.
[I-D.ietf-detnet-architecture] [I-D.ietf-detnet-architecture]
Finn, N., Thubert, P., Varga, B., and J. Farkas, Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", draft-ietf- "Deterministic Networking Architecture", draft-ietf-
detnet-architecture-10 (work in progress), December 2018. detnet-architecture-13 (work in progress), May 2019.
[PCE] IETF, "Path Computation Element", [PCE] IETF, "Path Computation Element",
<https://datatracker.ietf.org/doc/charter-ietf-pce/>. <https://datatracker.ietf.org/doc/charter-ietf-pce/>.
[RFC6997] Goyal, M., Ed., Baccelli, E., Philipp, M., Brandt, A., and [RFC6997] Goyal, M., Ed., Baccelli, E., Philipp, M., Brandt, A., and
J. Martocci, "Reactive Discovery of Point-to-Point Routes J. Martocci, "Reactive Discovery of Point-to-Point Routes
in Low-Power and Lossy Networks", RFC 6997, in Low-Power and Lossy Networks", RFC 6997,
DOI 10.17487/RFC6997, August 2013, DOI 10.17487/RFC6997, August 2013,
<https://www.rfc-editor.org/info/rfc6997>. <https://www.rfc-editor.org/info/rfc6997>.
[RFC7102] Vasseur, JP., "Terms Used in Routing for Low-Power and [RFC7102] Vasseur, JP., "Terms Used in Routing for Low-Power and
Lossy Networks", RFC 7102, DOI 10.17487/RFC7102, January Lossy Networks", RFC 7102, DOI 10.17487/RFC7102, January
2014, <https://www.rfc-editor.org/info/rfc7102>. 2014, <https://www.rfc-editor.org/info/rfc7102>.
Appendix A. Applications Appendix A. Applications
A.1. Loose Source Routing in Non-storing Mode A.1. Loose Source Routing in Non-storing Mode
A RPL implementation operating in a very constrained LLN typically A RPL implementation operating in a very constrained LLN typically
uses the Non-Storing Mode of Operation as represented in Figure 4. uses the Non-Storing Mode of Operation as represented in Figure 7.
In that mode, a RPL node indicates a parent-child relationship to the In that mode, a RPL node indicates a parent-child relationship to the
root, using a Destination Advertisement Object (DAO) that is unicast root, using a Destination Advertisement Object (DAO) that is unicast
from the node directly to the root, and the root typically builds a from the node directly to the root, and the root typically builds a
source routed path to a destination down the DODAG by recursively source routed path to a destination down the DODAG by recursively
concatenating this information. concatenating this information.
------+--------- ------+---------
| Internet | Internet
| |
+-----+ +-----+
skipping to change at page 16, line 21 skipping to change at page 18, line 33
+-----+ ^ | | +-----+ ^ | |
| | DAO | ACK | | | DAO | ACK |
o o o o | | | Strict o o o o | | | Strict
o o o o o o o o o | | | Source o o o o o o o o o | | | Source
o o o o o o o o o o | | | Route o o o o o o o o o o | | | Route
o o o o o o o o o | | | o o o o o o o o o | | |
o o o o o o o o | v v o o o o o o o o | v v
o o o o o o o o
LLN LLN
Figure 4: RPL non-storing mode of operation Figure 7: RPL non-storing mode of operation
Based on the parent-children relationships expressed in the non- Based on the parent-children relationships expressed in the non-
storing DAO messages,the root possesses topological information about storing DAO messages,the root possesses topological information about
the whole network, though this information is limited to the the whole network, though this information is limited to the
structure of the DODAG for which it is the destination. A packet structure of the DODAG for which it is the destination. A packet
that is generated within the domain will always reach the root, which that is generated within the domain will always reach the root, which
can then apply a source routing information to reach the destination can then apply a source routing information to reach the destination
if the destination is also in the DODAG. Similarly, a packet coming if the destination is also in the DODAG. Similarly, a packet coming
from the outside of the domain for a destination that is expected to from the outside of the domain for a destination that is expected to
be in a RPL domain reaches the root. be in a RPL domain reaches the root.
skipping to change at page 17, line 24 skipping to change at page 19, line 36
effectively become loose. effectively become loose.
A.2. Transversal Routes in storing and non-storing modes A.2. Transversal Routes in storing and non-storing modes
RPL is optimized for Point-to-Multipoint (P2MP) and Multipoint-to- RPL is optimized for Point-to-Multipoint (P2MP) and Multipoint-to-
Point (MP2P), whereby routes are always installed along the RPL DODAG Point (MP2P), whereby routes are always installed along the RPL DODAG
respectively from and towards the DODAG Root. Transversal Peer to respectively from and towards the DODAG Root. Transversal Peer to
Peer (P2P) routes in a RPL network will generally suffer from some Peer (P2P) routes in a RPL network will generally suffer from some
elongated (stretched) path versus the best possible path, since elongated (stretched) path versus the best possible path, since
routing between 2 nodes always happens via a common parent, as routing between 2 nodes always happens via a common parent, as
illustrated in Figure 5: illustrated in Figure 8:
o in non-storing mode, all packets routed within the DODAG flow all o in non-storing mode, all packets routed within the DODAG flow all
the way up to the root of the DODAG. If the destination is in the the way up to the root of the DODAG. If the destination is in the
same DODAG, the root must encapsulate the packet to place a same DODAG, the root must encapsulate the packet to place a
Routing Header that has the strict source route information down Routing Header that has the strict source route information down
the DODAG to the destination. This will be the case even if the the DODAG to the destination. This will be the case even if the
destination is relatively close to the source and the root is destination is relatively close to the source and the root is
relatively far off. relatively far off.
o In storing mode, unless the destination is a child of the source, o In storing mode, unless the destination is a child of the source,
skipping to change at page 18, line 21 skipping to change at page 20, line 23
+-----+ +-----+
X X
^ v o o ^ v o o
^ o o v o o o o o ^ o o v o o o o o
^ o o o v o o o o o ^ o o o v o o o o o
^ o o v o o o o o ^ o o v o o o o o
S o o o D o o o S o o o D o o o
o o o o o o o o
LLN LLN
Figure 5: Routing Stretch between S and D via common parent X Figure 8: Routing Stretch between S and D via common parent X
It results that it is often beneficial to enable transversal P2P It results that it is often beneficial to enable transversal P2P
routes, either if the RPL route presents a stretch from shortest routes, either if the RPL route presents a stretch from shortest
path, or if the new route is engineered with a different objective. path, or if the new route is engineered with a different objective.
For that reason, earlier work at the IETF introduced the "Reactive For that reason, earlier work at the IETF introduced the "Reactive
Discovery of Point-to-Point Routes in Low Power and Lossy Networks" Discovery of Point-to-Point Routes in Low Power and Lossy Networks"
[RFC6997], which specifies a distributed method for establishing [RFC6997], which specifies a distributed method for establishing
optimized P2P routes. This draft proposes an alternate based on a optimized P2P routes. This draft proposes an alternate based on a
centralized route computation. centralized route computation.
skipping to change at page 18, line 48 skipping to change at page 20, line 50
+-----+ +-----+
| |
o o o o o o o o
o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o
S>>A>>>B>>C>>>D o o o S>>A>>>B>>C>>>D o o o
o o o o o o o o
LLN LLN
Figure 6: Projected Transversal Route Figure 9: Projected Transversal Route
This specification enables to store source-routed or storing mode This specification enables to store source-routed or storing mode
state in intermediate routers, which enables to limit the stretch of state in intermediate routers, which enables to limit the stretch of
a P2P route and maintain the characteristics within a given SLA. An a P2P route and maintain the characteristics within a given SLA. An
example of service using this mechanism oculd be a control loop that example of service using this mechanism oculd be a control loop that
would be installed in a network that uses classical RPL for would be installed in a network that uses classical RPL for
asynchronous data collection. In that case, the P2P path may be asynchronous data collection. In that case, the P2P path may be
installed in a different RPL Instance, with a different objective installed in a different RPL Instance, with a different objective
function. function.
Appendix B. Examples Appendix B. Examples
B.1. Using storing mode P-DAO in non-storing mode MOP B.1. Using storing mode P-DAO in non-storing mode MOP
In non-storing mode, the DAG root maintains the knowledge of the In non-storing mode, the DAG root maintains the knowledge of the
whole DODAG topology, so when both the source and the destination of whole DODAG topology, so when both the source and the destination of
a packet are in the DODAG, the root can determine the common parent a packet are in the DODAG, the root can determine the common parent
that would have been used in storing mode, and thus the list of nodes that would have been used in storing mode, and thus the list of nodes
in the path between the common parent and the destination. For in the path between the common parent and the destination. For
instance in the diagram shown in Figure 7, if the source is node 41 instance in the diagram shown in Figure 10, if the source is node 41
and the destination is node 52, then the common parent is node 22. and the destination is node 52, then the common parent is node 22.
------+--------- ------+---------
| Internet | Internet
| |
+-----+ +-----+
| | Border Router | | Border Router
| | (RPL Root) | | (RPL Root)
+-----+ +-----+
| \ \____ | \ \____
skipping to change at page 19, line 43 skipping to change at page 21, line 47
o 22 o 23 o 24 o 25 o 22 o 23 o 24 o 25
/ \ | \ \ / \ | \ \
o 31 o 32 o o o 35 o 31 o 32 o o o 35
/ / | \ | \ / / | \ | \
o 41 o 42 o o o 45 o 46 o 41 o 42 o o o 45 o 46
| | | | \ | | | | | \ |
o 51 o 52 o 53 o o 55 o 56 o 51 o 52 o 53 o o 55 o 56
LLN LLN
Figure 7: Example DODAG forming a logical tree topology Figure 10: Example DODAG forming a logical tree topology
With this draft, the root can install a storing mode routing states With this draft, the root can install a storing mode routing states
along a segment that is either from itself to the destination, or along a segment that is either from itself to the destination, or
from one or more common parents for a particular source/destination from one or more common parents for a particular source/destination
pair towards that destination (in this particular example, this would pair towards that destination (in this particular example, this would
be the segment made of nodes 22, 32, 42). be the segment made of nodes 22, 32, 42).
In the example below, say that there is a lot of traffic to nodes 55 In the example below, say that there is a lot of traffic to nodes 55
and 56 and the root decides to reduce the size of routing headers to and 56 and the root decides to reduce the size of routing headers to
those destinations. The root can first send a DAO to node 45 those destinations. The root can first send a DAO to node 45
skipping to change at page 20, line 47 skipping to change at page 22, line 49
+-----+ +-----+
| P-DAO message to C | P-DAO message to C
o | o o o | o o
o o o | o o o o o o o o | o o o o o
o o o | o o o o o o o o o | o o o o o o
o o V o o o o o o o o V o o o o o o
S A B C D o o o S A B C D o o o
o o o o o o o o
LLN LLN
Figure 8: P-DAO from root Figure 11: P-DAO from root
Upon reception of the P-DAO, C validates that it can reach D, e.g. Upon reception of the P-DAO, C validates that it can reach D, e.g.
using IPv6 Neighbor Discovery, and if so, propagates the P-DAO using IPv6 Neighbor Discovery, and if so, propagates the P-DAO
unchanged to B. unchanged to B.
B checks that it can reach C and of so, installs a route towards D B checks that it can reach C and of so, installs a route towards D
via C. Then it propagates the P-DAO to A. via C. Then it propagates the P-DAO to A.
The process recurses till the P-DAO reaches S, the ingress of the The process recurses till the P-DAO reaches S, the ingress of the
segment, which installs a route to D via A and sends a DAO-ACK to the segment, which installs a route to D via A and sends a DAO-ACK to the
skipping to change at page 21, line 28 skipping to change at page 23, line 32
+-----+ +-----+
^ P-DAO-ACK from S ^ P-DAO-ACK from S
/ o o o / o o o
/ o o o o o o o / o o o o o o o
| o o o o o o o o o | o o o o o o o o o
| o o o o o o o o | o o o o o o o o
S A B C D o o o S A B C D o o o
o o o o o o o o
LLN LLN
Figure 9: P-DAO-ACK to root Figure 12: P-DAO-ACK to root
As a result, a transversal route is installed that does not need to As a result, a transversal route is installed that does not need to
follow the DODAG structure. follow the DODAG structure.
------+--------- ------+---------
| Internet | Internet
| |
+-----+ +-----+
| | Border Router | | Border Router
| | (RPL Root) | | (RPL Root)
+-----+ +-----+
| |
o o o o o o o o
o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o
S>>A>>>B>>C>>>D o o o S>>A>>>B>>C>>>D o o o
o o o o o o o o
LLN LLN
Figure 10: Projected Transversal Route Figure 13: Projected Transversal Route
Authors' Addresses Authors' Addresses
Pascal Thubert (editor) Pascal Thubert (editor)
Cisco Systems Cisco Systems
Village d'Entreprises Green Side Village d'Entreprises Green Side
400, Avenue de Roumanille 400, Avenue de Roumanille
Batiment T3 Batiment T3
Biot - Sophia Antipolis 06410 Biot - Sophia Antipolis 06410
FRANCE FRANCE
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