Network Working Group M. Richardson
Internet-Draft SSW
Intended status: Informational July 21, 2014
Expires: January 22, 2015
6tisch secure join using 6top
draft-richardson-6tisch--security-6top-02
Abstract
This document details a security architecture that permits a new
6tisch compliant node to join an 802.15.4e network. The process
bootstraps the new node authenticating the node to the network, and
the network to the node, and configuring the new node with the
required 6tisch schedule. Any resemblance to WirelessHART/IEC62591
is entirely intentional.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in RFC
2119 [RFC2119].
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-
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 22, 2015.
Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Assumptions . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology and Roles . . . . . . . . . . . . . . . . . . . . 4
3. Architectural requirements of join protocol . . . . . . . . . 6
3.1. prefixes to use for join traffic . . . . . . . . . . . . 9
4. security requirements . . . . . . . . . . . . . . . . . . . . 9
4.1. threat model . . . . . . . . . . . . . . . . . . . . . . 9
4.1.1. threats to the joining node . . . . . . . . . . . . . 9
4.1.2. threats to the resources of the network . . . . . . . 10
4.1.3. threats to other joining nodes . . . . . . . . . . . 11
4.2. implementation cost . . . . . . . . . . . . . . . . . . . 11
4.3. denial of service . . . . . . . . . . . . . . . . . . . . 11
5. protocol requirements/constraints/assumptions . . . . . . . . 12
5.1. inline/offline . . . . . . . . . . . . . . . . . . . . . 12
6. time sequence diagram . . . . . . . . . . . . . . . . . . . . 12
6.1. explanation of each step . . . . . . . . . . . . . . . . 13
6.1.1. step (1): enhanced beacon . . . . . . . . . . . . . . 13
6.1.2. step (1B): send router solicitation . . . . . . . . . 13
6.1.3. step (1C): receive router advertisement . . . . . . . 13
6.1.4. step (2): certificate cache load . . . . . . . . . . 13
6.1.5. step (3): receive certificate cache . . . . . . . . . 14
6.1.6. step (4): join request . . . . . . . . . . . . . . . 14
6.1.7. step (5): NS duplicate address request (DAR) . . . . 14
6.1.8. step (7): 6LBR informs JCE of new node . . . . . . . 14
6.1.9. step (8): JCE informs/acks to 6LBR of new node . . . 14
6.1.10. step (9): NS duplicate address confirmation (DAC) . . 14
6.1.11. step (10): JCE initiates connection to joining node . 14
6.1.12. step (11): Join Assistant forwards packet to joining
node . . . . . . . . . . . . . . . . . . . . . . . . 14
6.1.13. step (12): Joining node replies . . . . . . . . . . . 14
6.1.14. step (13): Join Assistant forwards reply to JCE . . . 14
6.2. size of each packet . . . . . . . . . . . . . . . . . . . 15
7. resulting security properties obtained from this process . . 15
8. deployment scenarios underlying protocol requirements . . . . 15
9. device identification . . . . . . . . . . . . . . . . . . . . 15
9.1. PCE/Proxy vs Node identification . . . . . . . . . . . . 15
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9.2. Time source authentication / time validation . . . . . . 15
9.3. description of certificate contents . . . . . . . . . . . 15
9.4. privacy aspects . . . . . . . . . . . . . . . . . . . . . 15
10. slotframes to be used during join . . . . . . . . . . . . . . 16
11. configuration aspects . . . . . . . . . . . . . . . . . . . . 16
12. authorization aspects . . . . . . . . . . . . . . . . . . . . 16
12.1. how to determine a proxy/PCE from a end node . . . . . . 16
12.2. security considerations . . . . . . . . . . . . . . . . 16
13. security architecture . . . . . . . . . . . . . . . . . . . . 16
14. Posture Maintenance . . . . . . . . . . . . . . . . . . . . . 16
15. Security Considerations . . . . . . . . . . . . . . . . . . . 16
16. Other Related Protocols . . . . . . . . . . . . . . . . . . . 16
17. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
18. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
19. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
19.1. Normative references . . . . . . . . . . . . . . . . . . 17
19.2. Informative references . . . . . . . . . . . . . . . . . 18
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction
A challenging part with constructing an LLN with nodes from multiple
vendors is providing enough security context to each node such that
the network communication can form and remain secure. Most LLNs are
small and have no operator interfaces at all, and even if they have
debug interfaces (such as JTAG) with personnel trained to use that,
doing any kind of interaction involving electrical connections in a
dirty environment such as a factory or refinery is hopeless.
It is necessary to have a way to introduce new nodes into a 6tisch
network that does not involve any direct manipulation of the nodes
themselves. This act has been called "zero-touch" provisioning, and
it does not occur by chance, but requires coordination between the
manufacturer of the node, the service operator running the LLN, and
the installers actually taking the devices out of the shipping boxes.
1.1. Assumptions
For the process described in this document to work, some assumptions
about available infrastructure are made. These are perhaps more than
assumptions, but rather architectural requirements; the exact
operation of said infrastructure to be defined in a subsequent
document.
In the diagrams and text that follows entities are named (and defined
in the terminology section). Unless otherwise stated these are
roles, not actual machines/systems. The roles are seperated by
network protocols in order that they roles can be performed by
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different systems, not because they have to be. Different
deployments will have different scaling requirements for those
entities. Smaller deployments might co-located many roles together
into a single ruggedized platform, while other deployments might
operate all of the roles on distinct, multiply-redundant server
classes located in a fully equipped datacentre.
2. Terminology and Roles
Most terminology should be taken from [I-D.ietf-6tisch-architecture]
and from [I-D.ietf-6tisch-6top-interface] and
[I-D.wang-6tisch-6top-sublayer]. As well, many terms are taken from
[RFC6775].
The following roles/things are defined:
PCE the Path Computation Engine. This entity reaches
out to each of the nodes in the LLN, and
configures an appropriate schedule using 6top.
Authz Server/ACE the Authorization Server. This offloads
calculation of access control lists and other
access control decisions for constrainted nodes.
See [I-D.seitz-ace-problem-description]
6top the 6top protocol is defined abstractly in
[I-D.ietf-6tisch-6top-interface] and mapped to
run over CoAP in [I-D.ietf-6tisch-coap]. The
6top protocol is defined primarily to provision
the 6TiSCH schedule; this document proposes to
extend it for also provisioning of layer-2
security parameters.
JCE the Join Coordination Entity. This acronym is
chosen to parallel the PCE.
joining node The newly unboxed constrained node that needs to
join a network.
join assistant A constrained node near the joining node that
will act as it's first 6LR, and will relay
traffic to/from the joining node.
join network A 802.15.4e network whose encryption and
authentication key is "JOIN6TISCH".
production network A 802.15.4e network whose encryption/
authentication keys are determined by some
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algorithm. There may have network-wide group
keys, or per-link keys.
The following terms are used in this document and come from other
documents:
DevID [IEEE.802.1AR] defines the secure DEVice
IDentifier as a device identifier that is
cryptographically bound to the device and is
composed of the Secure Device Identifier Secret
and the Secure Device Identifier Credential.
IDevID The Initial secure DEVice IDentifier (IDevID) is
the Device Identifier which was installed on the
device by the manufacturer.
LDevID A Locally significant secure DEVice IDentifiers
(LDevIDs) is a Secure Device Identifier
credential that is unique in the local
administrative domain in which the device is
used. The LDevID is usually a new certificate
provisioned by some local means, such as the 6top
mechanism defined in this document.
CoAP The CoAP protocol, defined in [RFC7252] is an
HTTP-like resource access protocol. CoAP runs
over UDP.
DTLS The datagram version of TLS, defined in
[RFC6347], and which can be used to secure CoAP
in the same way that TLS secures HTTP.
ARO [RFC6775]defines a number of new Neighbor
Discovery options including the Address
Registration Option
DAR/DAC [RFC6775]defines the Duplicate Address Request
and Duplicate Address Confirmation options to
turn the multicasted Duplicate Address Detection
protocol into a client/server process
EARO [I-D.thubert-6lo-rfc6775-update-reqs]extends the
ARO option to include some additional fields
necessary to distinguish duplicate addresses from
nodes that have moved networks when there are
mulitple LLNs linked over a backbone.
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3. Architectural requirements of join protocol
This section works from the ultimate goal, and goes backwards to
prerequisit actions. Section 6 presents the protocol from beginning
to end order.
The ultimate goal of the join protocol is to provide a new node with
enough locally significant security credentials that it is able to
take part in the network directly. The credentials may vary by
deployment. They can be:
1) a network-wide shared symmetric key
2) a locally significant (one-level only) 802.11AR type DevID
certificate
Given one of the the above, there are a number of possible protocols
that can be used to generate layer-2 sessions keys for the node,
including:
1) Mesh Link Exchange [I-D.kelsey-intarea-mesh-link-establishment]
2) work in 802.15.9
3) Security Framework and Key Management Protocol Requirements for
6TiSCH [I-D.ohba-6tisch-security] (this document provides the
phase 0 required)
4) Layer-2 security aspects for the IEEE 802.15.4e MAC
[I-D.piro-6tisch-security-issues]
The intermediate goal of the join protocol is to enable a Join
Coordination Entity (JCE) to reach out to the new node, and install
the credentials detailed above. The JCE must authenticate itself to
the joining node so that the joining node will know that it has
joined the correct network, and the joining node must authenticate
itself to the JCE so that the JCE will know that this node belongs in
the network. This two way authentication occurs in the 6top/CoAP/
DTLS session that is established between the JCE and the joining
node.
[I-D.ietf-6tisch-6top-interface] presents a way to interface to a
6top information model (defined in YANG). [I-D.ietf-6tisch-coap]
explains how to access that information model using CoAP. That model
is to be extended to include security attributes for the network.
The JCE would therefore reach out to the joining node and simply
provision appropriate security properties into the joining node, much
like the PCE will provision schedules.
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This 6top-based secure join protocol has defined a push model for
security provisioning by the JCE. This has been done for three
reasons:
1) 6tisch nodes already have to have a 6top CoAP server for schedule
provising
2) this permits the JCE to manage how many nodes are trying to join
at the same time, and limit how much bandwidth/energy is used for
the join operation, and also for the JCE to prioritize the join
order for nodes.
3) making the JCE initiate the DTLS connection significantly
simplies the certificate chains that must be exchanged as the
most constrained side (the joining node) provides it's
credentials first, and lets the much richer JCE figure out what
kind of certificate chain will be required to authenticate the
JCE. In EAP-TLS/802.1x situations, the TLS channel is created in
the opposite direction, and it would have to complete in a
tentative way, and then further authorization occur in-band.
In order for a 6top/DTLS/CoAP connection to occur between the JCE and
the joining node, there needs to be end-to-end IPv6 connectivity
between those two entities. The joining node will not participate in
the route-over RPL mesh, but rather will be seen by the network as
being a 6lowpan only leaf-node.
There are some alternatives to having full end to end connectivity
which are discussed in the security considerations section.
The specific mechanism to enable end to end connectivity with the JCE
are still open but will consist of one of:
(1) IPIP tunnel between Join Assistant and JCE
(2) using straight RPL routing: the Join Assistant sends a DAO
(3) using a separate RPL DODAG for join traffic
(4) establishing a specific multi-hop 6tisch track for join traffic
for each Join Assistant
Of these mechanisms, the only one which does not require additional
state on the Join Assistant (which is also a constrained device) is
(1) and (2). Mechanism (2) additionally requires no specific state
on the Join Assistant. Mechanism (2), in a non-storing DODAG
requires additional state on the DODAG root (6LBR) only; while
mechanism (1) requires a similar amount of state on the JCE. For
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deployments where the JCE is part of the 6LBR, the amount of state is
similar, but in any case, the 6LBR is assumed to be a non-constrained
node.
As long as the Join Assistant does not do any kind of stateful
firewalling, the IPIP tunnel and the DAO (2) method can be done by
the Join Assistant statelessly. Upward traffic from the Join Network
must be restricted to a 6tisch slotframe(s) to which join traffic is
welcome, no tunnelling is necessary as the upwards routes are all in
place. A destination address ACL on traffic from the Join Network
restricts the Joining Nodes to sending traffic only to the address of
the JCE. (If JCE and 6LBR are colocated, then this is the address in
the ABRO, if they are not colocated, then this address needs to have
been provisioning in the Join Assistant when it joined, or could be
carried in a new RA option)
When using option (2), networks that have storing mode DODAGs will
consume routing resources on all intermediate nodes between the Join
Assistant and the DODAG root. This resource will be depleted without
any authentication, and this threat is detailed below.
Continuing to work backwards, in order the JCE reach out to provision
the Joining Node, it needs to know that the new node is present.
This is done by taking advantage of the 6lowPAN Address Resolution
Option (ARO) (section 4.1 [RFC6775]). The ARO causes the new address
to also be sent up to the 6LBR for duplicate detection using the DAR/
DAC mechanism. The 6LBR simply needs to tell the JCE about this
using a protocol that needs to be defined, but could be either DAR or
NS.
In addition to needing to know the joining devices address from the
DAR/NS, the JCE also needs to know the joining node' IDevID. If the
serialNumber attribute of the IDevID is less than 64 bits, then it is
possible that it could be placed into the EUI-64 option of the ARO,
or the OUI of the [I-D.thubert-6lo-rfc6775-update-reqs] EARO. The
JCE needs to know the joining node's serialNumber to know if this is
device that it should even attempt to provision; and if so, it may
need to retrieve an appropriate certificate chain (see
[I-D.richardson-6tisch-idevid-cert]) from the Factory in order for
the JCE to prove it is the legitimate owner of the joining node.
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Neither 802.1AR nor [RFC5280] provide any structure for the
serialNumber, except that they are positive integers of up-to 20
octets in size (numbers up to 2^160). This specification would
require that the serialNumber encoded in the IDevID is the same as
the EUI-64 used by the device. Some consideration needs to be given
as to whether there are privacy considerations to doing this: any
observer that can see the join traffic, can also see the source MAC
address of the node as well.
Prior to being able to announce itself in a NS, the joining node
needs to find the Join Network. This is done by listening to an
extended beacon which are broadcast in designated slotframes by Join
Assistants. The Extended Beacon provides a way for the Joining Node
to synchronize itself to the overall timeslot schedule and provides
an Aloha period in which the Joining Node can send a Router
Soliticiation, and receive an appropriate Router Advertisement giving
the Joining Node a prefix and default route to which to send join
traffic.
It may be possible to eliminate a message exchange if space for a
Router Advertisement can be found as part of the Join Network
Extended Beacon. This Enhanced Beacon would be distinct to the Join
Network, and would be encrypted with the well-known Join Network key.
3.1. prefixes to use for join traffic
What prefix would the joining node for communication? There are
three options:
(1) just use link-local addresses (requires all traffic be tunneled)
(2) use a prefix specifically for join traffic (may be easier with a
join-only DODAG)
(3) use the same prefix as the rest of the traffic (may require more
complex ACLs, and leaks information to attackers)
4. security requirements
4.1. threat model
There are three kinds of threats that a join process must deal with:
threats to the joining node, threats to the resources of the network,
and threats to other joining nodes.
4.1.1. threats to the joining node
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A node may be taken out of it's box by a malicious entity and powered
on. This could happen during shipping, while being stored in a
warehouse. The device may be subject to physical theft, or the goal
of the attacker may be to turn the device into a trojan horse of some
kind. Physical protection of the device is out of scope for this
document; this document will henceforth assume that the device is
sealed in some tamper-evident way and this document deals with
attacks over the network.
An attacker may attempt to convince the joining node that it is the
legitimate Production Network; this is done by putting up a
legitimate looking Join Network, and following the protocol as
described in this document. The Joining Node can not know if it has
the corrrect Production Network until steps 11-13, when it attempts
to validate the ClientCertificate provided by the JCE.
When the joining node determines that this is the incorrect network,
it must remember the PANID of the network that it has attempted to
join, and then look for another network to try. It SHOULD have some
limit as the number of times it will try before going back to sleep,
or shutting down, and it SHOULD take care not to consume more than
some specified percentage of any battery it might have.
Should a malicious production network be present at the same time/
place as the legitimate production network, a the malicious agent
could intercept and replay various packets from the proper join
network, but ultimately this either results in a jamming-like denial
of service, and/or the the ClientCertificate will not validate.
It is a legitimate situation for there to be multiple possible join
networks, and the joining node may have to try each one before it
finds the network that it the right one for it. The incorrect, but
non-malicious networks will not attempt the 6top provisioning step,
and SHOULD return a negative result in steps 8/9, refusing the node's
NS. Those incorrect networks will be recognize that the node does
not belong to them, because they will be able to see the Joining
Node's IDevID in the ARO of step 4.
4.1.2. threats to the resources of the network
The production network has two important resources that may be
attacked by malicious Joining nodes: 1) energy/bandwidth, 2) memory
for routing entries.
A malicious joining node could send many NS messages to the Join
Assistant (from many made up addresses), which would send many NS/DAR
messages to the 6LBR, and this would consume bandwidth, and therefore
energy from the members of the mesh along the path to the 6LBR. This
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can be mitigated by limited the total bandwidth available for
joining.
A malicious joining node could send many NS messages, and if the 6LBR
agreed to accept the new node (by IDevID), then the Join Assistant
would MAY inject routing information into mesh for the Joining node.
Non-storing DODAGs store are routing information in the DODAG Root
(probably the 6LBR), which is generally not a constrained node.
Storing DODAGs store routing entries at all nodes up to the DODAG,
and those are constrained nodes. Using a separate Join DODAG, and
having that DODAG be non-storing will reduce any impact on
intermediate nodes, but it does cause resources to be used for the
second DODAG, and it may have a code impact if the nodes otherwise
would not implement non-storing RPL.
4.1.3. threats to other joining nodes
A joining node (or the nodes of a malicious network, co-located near
the legitimate production network) may mount attacks on legitimate
nodes which have not yet joined.
The malicious nodes may attempt to perform 6top operations against
the joining node to keep it from being able to respond to the
legitimate 6top session from the legitimate JCE. During the Join
phase, the Joining node MUST have all other resources and protocols
turned off, even if they would normally be accessible as read-only
unauthenticated CoAP resources.
Malicious nodes could use the Join Network to mount various DTLS
based attacks against the joining node, such as sending very long
certificate chains to validate. One might think to limit the length
of such chains, but as shown in [I-D.richardson-6tisch-idevid-cert]
the chain may as a long as the supplier chain, plus may include
additional certificates due to resales of plants/equipment/etc.
Validating from a trusted certificate down to the specific
certificate which proves ownership would eliminate random certificate
chains, but the attacker could just feed the joining node legitimate
chains that it observed (and replayed) from the legitimate JCE. This
does no good; the Joining node finds that the DTLS connection is
invalid, but it may significantly run batteries down.
4.2. implementation cost
(storage of security material, computational cost)
4.3. denial of service
other communication impacts of security protocol mechanics
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5. protocol requirements/constraints/assumptions
5.1. inline/offline
dependencies on centralized or external functionality, inline and
offline
6. time sequence diagram
+-----+ +------+ +----------+ +-----------+
| | | | | JOIN | | Joining |
| JCE | | 6LBR | | Assistant| | Node |
+-----+ +------+ | (proxy) | | |
| | +----------+ +-----------+
| | | |
| | |-------BEACON (1)---------->|
| | | |
| | |<----Router Solicitation----|
| | |---Router Advertisement---->|
| | | |
| | |<------CERT CACHE-----------|
| | | LOAD (2) |
| | | |
| | | |
| | |-------CERT CACHE---------->|
| | | RESPONSE (multiple) |
| | | (packets) |
| | | |
| | |<-----JOIN REQUEST (4) -----|
| | | (NS w/ARO ) |
| | | |
| |<---NS (DAR) (5)-----| |
|<--??(6)-| | |
| | | |
|--??(7)->| | |
| | | |
| |----NS (DAC)-(8)---->| |
| | +------+ | |
| |<DAO-| mesh |<--DAO--| |
| |-DAO-| node |--DACK->| |
| | ACK +------+ | |
| | |-------JOIN ACK (9)-------->|
| | | |
| | | |
|================(10)==========>|----------6top----(11)----->|
| | | DTLS |
|<===============(13)===========|<---------CoAP----(12)------|
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| | | (many packets) |
Figure 1: Message sequence for JOIN message
6.1. explanation of each step
6.1.1. step (1): enhanced beacon
A 6tisch join/synchronization beacon is broadcast periodically, and
is authenticated with a symmetric "beacon key":
well known JOIN key, such "JOIN6TISCH"
another key, provisioned in advance (OOB)
a shared symmetric key derived from public part of top level
certificate (a closely held "secret")
The purpose of this key is not to provide a high level of assurance,
but rather to filter out 6tisch traffic from another random traffic
that may be sharing the same radio frequencies.
These beacons are used for JOIN purpose only, and are not related to
the Enhanced Beacons used in the rest of 6tisch.
6.1.2. step (1B): send router solicitation
The joining node sends a router solicitation during the Aloha period
of the beacon.
6.1.3. step (1C): receive router advertisement
The joining node receives a router advertisement from the Join
Assistant. It could include 6CO options to help compress packets,
and should contain a prefix appropriate for join traffic.
6.1.4. step (2): certificate cache load
At step 10, the JCE will need to present a certificate chain anchored
at a trusted CA built into the joining node. It has been speculated
that a significant amount of traffic could be avoided at step (10) if
the common parts of the certificate chains could be cached in the
join assistant.
This optional step involves the joining node asking for certificates
from the join assistant.
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6.1.5. step (3): receive certificate cache
the proxy neighbour sends requested cached certificates to the
joining node
6.1.6. step (4): join request
A regular Neighbour Solicitation is sent. This should contain an ARO
(or EARO) option containing the Joining Nodes' IDevID. The ARO/EARO
will be proxied by the Join Assistant as part of normal 6LowPAN
processing for leaf nodes (non-RPL nodes) upwards to the 6LBR
6.1.7. step (5): NS duplicate address request (DAR)
6.1.8. step (7): 6LBR informs JCE of new node
6.1.9. step (8): JCE informs/acks to 6LBR of new node
The JCE could reply in the negative, and this would cause a DAC
failure, TBD
6.1.10. step (9): NS duplicate address confirmation (DAC)
6.1.11. step (10): JCE initiates connection to joining node
The double lines indicate that an IPIP tunnel operation may be
required. If a straight DAO or seperate Join DODAG is used, then
this is just a straight forwarding root to leaf node forwarding
operation, and involves either using source routes (non-storing), or
just forwarding for storing DODAGs.
A specific bandwidth allocation would be used for this join traffic
The production network encryption keys would be used for the join
traffic
6.1.12. step (11): Join Assistant forwards packet to joining node
The JOIN Assistant would forward traffic to the Joining Node.
Recognizing that this traffic the JOIN Network, the JOIN Assistant
would use the JOIN Network key.
6.1.13. step (12): Joining node replies
The joining node replies, using JOIN Network key.
6.1.14. step (13): Join Assistant forwards reply to JCE
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The JOIN Assistant, recognizing that the traffic came from the JOIN
Network, restricts the destination that can be reached to the the JCE
only. It can do this in a stateless way, and it does NOT need to
track the traffic at (10) to open pinhole, etc.
Recognizing that the traffic came from the JOIN Network, the traffic
would be placed into a bandwidth allocation (track?) that allows such
traffic.
6.2. size of each packet
and number of frames needed to contain it.
7. resulting security properties obtained from this process
An end to end IPv6 CoAP/DTLS connection is created between the JCE
and the Joining Node. This connection carries 6top commands to
update security parameters. This results in either deployment of a
single-level, locally relevant certificate (LDevID), or deployment of
a network-wide symmetric "Master Key"
8. deployment scenarios underlying protocol requirements
9. device identification
The JCE authenticates the joining node using a certificate chain
provided inline during the DTLS negotiation. The certificate chain
is rooted in a vendor certificate that the JCE must have preloaded,
and is a statement as to the node's 802.1AR IDevID. The joining node
authenticates the
9.1. PCE/Proxy vs Node identification
9.2. Time source authentication / time validation
Note: RPL Root authentication is a chartered item
9.3. description of certificate contents
9.4. privacy aspects
The EUI-64 of the Joining node is transmitted using a Well Known
layer-2 encryption key. Within the ARO/EARO of the Neighbour
Solicitation is an OUI, which may be identical to the EUI-64 of the
Joining node, or it might be an unrelated IDevID.
An eavesdropper can therefore learn something about the manufacturer
of every device as it joins.
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10. slotframes to be used during join
how is this communicated in the (extended) beacon.
11. configuration aspects
(allocation of slotframes after join, network statistics,
neighboetc.)
12. authorization aspects
lifecycle (key management, trust management)
12.1. how to determine a proxy/PCE from a end node
12.2. security considerations
what prevents a node from transmitting when it is not their turn
(part one: jamming)
can a node successfully communicate with a peer at a time when not
supposed to, may be tied to link layer security, or will it be
policed by receiver?
13. security architecture
security architecture and fit of e.g. join protocol and provisioning
into this
14. Posture Maintenance
(SACM related work)
15. Security Considerations
16. Other Related Protocols
17. IANA Considerations
18. Acknowledgements
19. References
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19.1. Normative references
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC6550] Winter, T., Thubert, P., Brandt, A., Hui, J., Kelsey, R.,
Levis, P., Pister, K., Struik, R., Vasseur, JP., and R.
Alexander, "RPL: IPv6 Routing Protocol for Low-Power and
Lossy Networks", RFC 6550, March 2012.
[RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann,
"Neighbor Discovery Optimization for IPv6 over Low-Power
Wireless Personal Area Networks (6LoWPANs)", RFC 6775,
November 2012.
[IEEE.802.1AR]
Institute of Electrical and Electronics Engineers, "Secure
Device Identity", IEEE 802.1AR, 2009,
<http://www.ieee802.org/1/pages/802.1ar.html>.
[I-D.ietf-6tisch-coap]
Sudhaakar, R. and P. Zand, "6TiSCH Resource Management and
Interaction using CoAP", draft-ietf-6tisch-coap-01 (work
in progress), July 2014.
[I-D.ietf-6tisch-6top-interface]
Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH
Operation Sublayer (6top) Interface", draft-ietf-6tisch-
6top-interface-01 (work in progress), July 2014.
[I-D.ietf-6tisch-architecture]
Thubert, P., Watteyne, T., and R. Assimiti, "An
Architecture for IPv6 over the TSCH mode of IEEE
802.15.4e", draft-ietf-6tisch-architecture-01 (work in
progress), February 2014.
[I-D.irtf-nmrg-autonomic-network-definitions]
Behringer, M., Pritikin, M., Bjarnason, S., Clemm, A.,
Carpenter, B., Jiang, S., and L. Ciavaglia, "Autonomic
Networking - Definitions and Design Goals", draft-irtf-
nmrg-autonomic-network-definitions-00 (work in progress),
December 2013.
[I-D.seitz-ace-problem-description]
Seitz, L. and G. Selander, "Problem Description for
Authorization in Constrained Environments", draft-seitz-
ace-problem-description-01 (work in progress), July 2014.
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[I-D.richardson-6tisch-idevid-cert]
Richardson, M., "X509.v3 certificate extension for
authorization of device ownership", draft-richardson-
6tisch-idevid-cert-00 (work in progress), May 2014.
[I-D.wang-6tisch-6top-sublayer]
Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH
Operation Sublayer (6top)", draft-wang-6tisch-6top-
sublayer-00 (work in progress), February 2014.
[I-D.thubert-6lo-rfc6775-update-reqs]
Thubert, P., "Requirements for an update to 6LoWPAN ND",
draft-thubert-6lo-rfc6775-update-reqs-01 (work in
progress), June 2014.
19.2. Informative references
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252, June 2014.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, January 2012.
[I-D.thubert-6lowpan-backbone-router]
Thubert, P., "6LoWPAN Backbone Router", draft-thubert-
6lowpan-backbone-router-03 (work in progress), February
2013.
[I-D.ietf-netconf-zerotouch]
Watsen, K., Hanna, S., Clarke, J., and M. Abrahamsson,
"Zero Touch Provisioning for NETCONF Call Home
(ZeroTouch)", draft-ietf-netconf-zerotouch-00 (work in
progress), July 2014.
[I-D.kelsey-intarea-mesh-link-establishment]
Kelsey, R., "Mesh Link Establishment", draft-kelsey-
intarea-mesh-link-establishment-05 (work in progress),
February 2013.
[I-D.ohba-6tisch-security]
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Chasko, S., Das, S., Lopez, R., Ohba, Y., Thubert, P., and
A. Yegin, "Security Framework and Key Management Protocol
Requirements for 6TiSCH", draft-ohba-6tisch-security-01
(work in progress), March 2014.
[I-D.piro-6tisch-security-issues]
Piro, G., Boggia, G., and L. Grieco, "Layer-2 security
aspects for the IEEE 802.15.4e MAC", draft-piro-6tisch-
security-issues-02 (work in progress), June 2014.
Author's Address
Michael C. Richardson
Sandelman Software Works
470 Dawson Avenue
Ottawa, ON K1Z 5V7
CA
Email: mcr+ietf@sandelman.ca
URI: http://www.sandelman.ca/
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