ACE Working Group C. Schmitt
Internet-Draft B. Stiller
Intended status: Standards Track University of Zurich
Expires: January 1, 2016 M. Noack
June 30, 2015
Two-way Authentication for IoT
<draft-schmitt-ace-twowayauth-for-iot-02>
Abstract
In this draft a full two-way authentication security scheme for the
Internet of Things (IoT) based on existing Internet standards and
protocols is introduced. The solution is twofold providing a two-way
authentication for resource-rich hardware (e.g., class 2 devices with
~50 KiB RAM and ~250 KiB ROM [RFC7228]) and for devices with less
resources (e.g., class 1 devices with ~10 KiB RAM and ~100 KiB ROM
[RFC7228]). By relying on an established standard, existing
implementations, engineering techniques, and security infrastructure
can be reused, which enables an easy security uptake. The proposed
security scheme for resource-rich devices is, therefore, based on
RSA, the most widely used public key cryptography algorithm. It is
designed to work over standard communication stacks that offer UDP/
IPv6 networking for Low power Wireless Personal Area Networks
(6LoWPANs). RSA is a bulky solution at the moment but shows that it
is possible using it on constraint devices for security purposes. An
optimization is the usage of elliptic curve cryptography (ECC) as
assumed for devices with less resources.
Status of this Memo
This Internet-Draft is submitted to IETF 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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Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 1, 2016.
Copyright Notice
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Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Document Structure . . . . . . . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. High Level Design Requirements . . . . . . . . . . . . . . . . 5
3.1. Implementation of A Standards Based Design . . . . . . . . 5
3.2. Focus on Application Layer and End-to-End Security . . . . 6
3.3. Support for UDP . . . . . . . . . . . . . . . . . . . . . 6
4. End-to-End Security Using Two-way authentication . . . . . . . 7
4.1. Class 2 Devices or Higher . . . . . . . . . . . . . . . . 7
4.1.1. Handshake Description . . . . . . . . . . . . . . . . 8
4.1.2. Certificate Creation . . . . . . . . . . . . . . . . . 9
4.2. Class 1 Devices . . . . . . . . . . . . . . . . . . . . . 10
4.2.1. Handshake . . . . . . . . . . . . . . . . . . . . . . 10
5. Architecture Description . . . . . . . . . . . . . . . . . . . 11
5.1. Use-cases . . . . . . . . . . . . . . . . . . . . . . . . 11
5.2. Requirements . . . . . . . . . . . . . . . . . . . . . . . 12
5.3. Data Access Procedure . . . . . . . . . . . . . . . . . . 13
6. Hardware Requirements . . . . . . . . . . . . . . . . . . . . 15
6.1. Class 2 Hardware Requirements . . . . . . . . . . . . . . 15
6.2. Class 1 Hardware Requirements . . . . . . . . . . . . . . 16
7. Security Considerations . . . . . . . . . . . . . . . . . . . 16
7.1. Class 2 Security Considerations . . . . . . . . . . . . . 16
7.2. Class 1 Security Considerations . . . . . . . . . . . . . 16
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
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9. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 17
10. Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . . 17
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
11.1. Norminative References . . . . . . . . . . . . . . . . . . 18
11.2. Informative References . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20
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1. Introduction
Today, there is a multitude of envisioned and implemented use cases
for the Internet of Things (IoT) and wireless sensor networks
(WSNs).In many of these scenarios it is intended to make the
collected data globally accessible to authorized users and data
processing units through the Internet. Most of these data collected
in such scenarios is of sensitive nature due to the relation to
location and personal information or IDs. Even seemingly
inconspicuous data, such as the energy consumption measured by a
smart meter, can lead to potential infringements in the users'
privacy, e.g., by allowing an eavesdropper to conclude whether or not
a user is currently at home. From an industry perspective, there is
also a pressing need for security solutions based on standards as
pointed out by the market research firm Gartner Inc. [1]. Regarding
the infrastructure, security risks are aggravated by the trend toward
a separation of sensor network infrastructure and applications.
Therefore, a true end-to-end security solution is required to achieve
an adequate level of security for IoT. Protecting the data once it
leaves the scope of the local network is not sufficient.
A similar scenario in the traditional computing world would be a user
browsing the Internet over an unsecured WLAN. Assuming attackers in
physical proximity of the user it can happen that the attacker can
capture the traffic between the user and a Web server.
Countermeasures against such attacks include the establishment of a
secured connection to the Web server via HTTPS, the use of a VPN
tunnel to securely connect to a trusted VPN endpoint, and using
wireless network security such as WPA.
These solutions are comparable to security approaches in the IoT
area. Using WPA is similar to the traditional use of link layer
encryption. The VPN solution is equivalent to creating a secure
connection between a sensor node and a security end-point, which may
or may not be the final destination of the sensor data. Establishing
a HTTPS connection with the server is comparable to the approach
described in this draft: The use of the DTLS protocol in an end-to-
end security architecture for IoT is investigated, where a two-way
authentication handshake is processed in order to establish a secured
communication channel requiring authentication of both communication
parties. Due to high resource requirements, especially memory and
computational capacities, devices with additional hardware like TPM
can perform this solution (e.g., class 2 devices with ~50 KiB RAM and
~250 KiB ROM [RFC7228]). More constraint devices (e.g., class 1
devices with ~10 KiB RAM and ~100 KiB ROM [RFC7228]) can perform two-
way authentication using ECC [2] instead.
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1.1. Document Structure
Section 2 mentions conventions used in this draft. Afterwards the
assumed high level design requirements are briefly mentioned in
Section 3. Section 4 describes a two-way authentication handshake
for constraint devices in order to establish an end-to-end security
in constraint networks (e.g., wireless sensor networks). This
section consists of two parts specifying the solution for resource-
rich devices (class 2 devices, for example, supporting Trusted
Platform Module (TPM)) and for resource less devices (class 1). The
parts include description of the handshake and message details. The
assumed use-case with its requirements and architecture is described
in Section 5. Section 6 defines the hardware requirements, followed
by security considerations and IANA considerations.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
A publisher represents any kind of device that makes its data public
available in a network using WLAN or LAN connection.
A subscriber represents any kind of device that wants to access data.
An Access Control server (AC) is an entity in the network that
regulates the access of data and issues an access ticket for
subscribers based on legal and regulative implications.
3. High Level Design Requirements
Due to the usage of DTLS for establishing an end-to-end security
architecture for IoT three high-level design decisions have to be
made.
3.1. Implementation of A Standards Based Design
Standardization has helped the widespread uptake of technologies.
Radio chips can rely on IEEE 802.15.4 for the physical and the MAC
layer. Routing functionality is provided by the so-called 'IPv6
Routing Protocol for Low power and Lossy Networks' (RPL) [RFC6550] or
6LoWPAN [RFC4944]. COAP [RFC7252] defines the application layer. So
far, no such efforts have addressed security in a wider context of
IoT.
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3.2. Focus on Application Layer and End-to-End Security
An end-to-end protocol provides security even if the underlying
network infrastructure is only partially under the user's control.
As the infrastructure for Machine-to-Machine (M2M) communication is
getting increasingly commoditized, this scenario becomes more likely:
The European Telecommunications Standard Institute (ETSI) plans to
standardize the transport of local device data to a remote data
center. For stationary installations security functionality could be
provided by the gateway to the higher-level network. However, such
gateways may present a high-value target for an attacker. If the
devices are mobile, as it is possible within a logistic application,
there may be no gateway to a provider's network that is under the
user's control, similar to how users of smart phones connect directly
to their carrier's network. Another example that favors end-to-end
security is a multi-tenancy office building being equipped with a
common infrastructure for metering and climate-control purposes.
Tenants share the infrastructure but are still able to keep their
devices' data private from other members of the network.
DTLS is located between the transport and the application layer.
Thus, it is not necessary that providers of the infrastructure
support security mechanisms. It is purely in the hands of the two
communicating applications to establish security. If the security is
provided by a network layer protocol (e.g., IPsec) the same is true
to a lower degree, because network stacks of both devices have to
support the same security protocols.
3.3. Support for UDP
Reliable transport protocols like TCP incur an overhead over simpler
protocols such as UDP. Especially for energy starved, battery
powered devices this overhead is often too costly and TCP has been
shown to perform poorly in low-bandwidth scenarios [3]. This is
reflected in the design of the emerging standard COAP, which uses UDP
transport and defines a binding to DTLS for security [RFC7252]. By
using DTLS in conjunction with UDP this draft does not force the
application developer to use reliable transport - as it would be the
case if TLS would be used. It is still possible to use DTLS over
transport protocols like TCP, since DTLS only assumes unreliable
transport.
This is a weaker property than the reliability provided by TCP.
However, adaptations of DTLS for unreliable transport introduce
additional overhead when compared to TLS. There MAY be a benefit in
using TCP during the handshake phase but the DTLS reliability
mechanism SHOULD be adapted to the special requirements of constraint
networks.
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4. End-to-End Security Using Two-way authentication
End-to-end security using two-way authentication requires lots of
resources depending on the selected solution. Here two solutions are
presented using two device classes. The more resource consuming
solution requires devices with ~50 KiB RAM and ~250 KiB RAM (e.g.,
class 2) as a minimum. Details are in Section 4.1. A two-way
authentication solution using ECC gets along with smaller devices
(e.g., class 1 devices with ~10 KiB RAM and ~100 KiB ROM) as
describes in Section 4.2.
4.1. Class 2 Devices or Higher
The proposed system architecture in this draft is following the IoT
model. It is assumed that IPv6 connects the Internet and parts of it
run 6LoWPAN. The transport layer in 6LoWPAN is UDP, which can be
considered unreliable; the routing layer is RPL or Hydro [3]. Both
routing protocols are similar enough and, therefore, a change has
negligible impact on the results. IEEE 802.15.4 is used for the
physical and MAC layer. Based on this protocol stack DTLS was
selected as the security protocol and placed in the application layer
on top of the UDP transportation layer. Figure 1 shows the network
stack used in this draft [6], while BLIP is a special 6LoWPAN
implementation including several IP protocols [7].
+--------------------------------------+
| Application Layer: COAP, XML, .... |
| |
| +-------------------------+ |
| | Security Layer: DTLS | |
| +-------------------------+ |
+--------------------------------------+
| Transport Layer: UDP-- |
| |-->BLIP,RPL |
| Network Layer: IPv6--- |
+--------------------------------------+
| Medium Access Layer: IEEE 802.15.4 |
+--------------------------------------+
| Physical Layer: IEEE 802.15.4 |
+--------------------------------------+
Figure 1: Assumed Network Stack
In order to support end-to-end communication security the need for
proper authentication of data publishing devices and access control
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throughout the network is required. Thus, an Access Control (AC)
server is integrated in the assumed system architecture. The AC is a
trusted entity and a resource-rich server, on which access rights for
the publisher (= sensor nodes) of the secured network are stored.
The identity of a default subscriber is usually preconfigured on a
publisher before it is deployed.
If any additional subscribers want to initialize a connection with
the publisher, they first have to obtain an access ticket from the
AC. The AC verifies that the subscriber has the right to access the
information available from the publisher. In the next step the
publisher only has to evaluate the identity of the subscriber and has
to verify the ticket it has received from the AC. This requires a
unique identity for a publisher in the network.
In the Internet, identities are usually established via public key
cryptography (PKC) and identifiers are provided through X.509
certificates. An X.509 certificate contains, among other
information, the public key of an entity and its common name. A
trusted third party, called the Certificate Authority (CA), signs the
certificate.
The CA serves two purposes: Firstly, the signature allows the
receiver to detect modifications to the certificate. Secondly, it
also states that the CA has verified the identity of the entity that
requested the certificate. In the following sections the proposed
two-way authentication handshake is specified and message structure
is presented in detail.
4.1.1. Handshake Description
Based on the hardware equipment (cf. Section 6) the proposed two-way
authentication handshake has to support a solution for class 2
devices or higher.
Figure 2 summarizes the message flow during the two-way
authentication handshake. Here client and server represent the two
communication parties that want to exchange data. Client
(Subscriber) is each entity that requests data from another entity
and a server (Publisher) can be each entity that has the data.
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Client (A) Server (B)
| |
|---ClientHello------------------------------------------>|
| |
|<------------------------------------ClientHelloVerify---|
| |
|---ClientHello------------------------------------------>|
| |
| ServerHello, Certificate, |
|<-----------------[CertificateRequest],ServerHelloDone---|
| |
| [Certificate], ClentKeyExchange, |
|---[CertificateVerify], ChangeCipherSpec, Finished------>|
| |
|<---------------------------ChangeCipherSpec, Finished---|
| |
| |
Figure 2: Message Flow of Two-way Authentication Handshake for Class
2 Devices
4.1.2. Certificate Creation
When the network consists of class 2 devices or higher it is
processed like shown in Figure 2. Before deploying the devices
certificates and individual 2048 bit RSA keys should be created and
stored. Therefore, it is recommended to use an OpenSSL
implementation on the server site [13].
The certificate should include the following details:
1. Serial number
2. Validity:
* Not Before: Date and time
* Not After: Date and time
3. Subject
* commonName = localhost
4. X509v3 extensions:
* X509v3 Basic Constraints: CA:FALSE
* Netscape Comment: OpenSSL Generated Certificate
* X509v3 Subject Key Identifier
* X509v3 Authority Key Identifier
Depending on the implementation additional information should be
requested that will be incorporated into the certificate request.
This informatiion may include the following:
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1. Country Name (2 letter code) [CH]
2. State or Providence Name (full name) [Zurich]
3. Locality Name (e.g., city) [Zurich-Oerlikon]
4. Organization Name (e.g., company) [UZH]
5. Organisation Unit Name (e.g., section) [IFI]
6. Common Name (e.g., YOUR name) [opal-device10]
7. Email Address []
8. optional
* A challenge password []
* An optional company name []
4.2. Class 1 Devices
The prosposed solution for class 1 devices requests the same network
stack as for higher devices shown in Figure 2. Instead of working
with X.509 certificates each device is deployed with an unique pre-
shared key (PSK) of 16 Byte length [2]. This key is the initial key
material that is used for resource saving ECC for performed PKC. ECC
[RFC6090] itself offers efficient algorithms (ECDSA [RFC5280], ECIES
[16], ECDH [RFC5280]) for key generation, key exchange, encryption,
decryption, and signatures. For message encryption an integrated
encryption scheme (IES) is recommendated to harness the speed-
advantage of symmetric encryption for large amount of data without
drawback of a repeated key exchange for every transmission to avoid
reusage of secrets.
4.2.1. Handshake
In order to achieve two-way authentication for class 1 devices the
Bellare-Canetti-Krawczyk (BCK) protocol [15] with pre-shared key is
recommendated [2]. Those pre-shared keys are master keys for initial
authentication between two devices (e.g., client and server).
Figure 3 shows the recommendated handshake between two devices.
ECC is used for key generation, key exchange, encryption, decryption,
and signatures during the data exchange. The public ECC keys are
decomposed into x and y-coordinates for easy handling on the mote
side. Elliptic Curve Digital Signature Algorithm (ECDSA) signatures
are integer keypairs, written as (r, s), and therefore difficult to
include in a fixed-length packet, because the bit-length of the
hexadecimal representation of large integers may vary. [2]
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Client (A) Server (B)
| |
|---------- X_A, H(K, X_A) -------------->|
| |
|<-- X_B, Sig_B (X_B,X_A, A), H(K, X_B) --|
| |
|-------- Sig_A (X_A, X_B, B) ----------->|
| |
Figure 3: Message Flow of Two-way Authentication Handshake for Class
1 Devices
X_A is the public key of client (A), respectivly X_B of server (B).
Sig_A is the signature of client (A), respectively Sig_B of server
(B). K represents the PSK. H is a hash function created from the
PSK and the corresponding public key, resulting in H(K, X_A) or H(K,
X_B).
5. Architecture Description
As briefly mentioned in Section 1 data is connected to sensitive
information and can lead to potential infringements in the users'
privacy. This fact becomes a security risk if the data is
transmitted over long distances, perhaps several hops, to a specified
global sink [10]. Depending on the setting it might happen that the
data is also transmitted via the Internet and might be cached in
between. The latter case is inspired by the project FLAMINGO, which
deals with access regulations based on legal and regulative
implications in IP networks [9]. By definition of the Internet of
Things it can be assumed that IP communication is supported by all
devices in wireless sensor networks, which allows the adaptation of
standards in IP networks to constraint networks.
5.1. Use-cases
The idea of the Internet of Thing includes any device connection that
supports IPv6 communication. Thus, the diversity of use-cases is
manifold and not limited to the following list of use-cases:
Home Automation
Different devices (e.g., temperature, light, movement sensors) are
deployed in a house. Those devices transmit collected data to a
central entitiy that is responsible for further processing
including data publishing if other devices (e.g., HVAC unit,
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mobile devices) subscribe to data in order to create an action
(e.g., turn on heating or light).
Health Monitoring
Devices are carried by patients that monitor health status (e.g.,
heart beat, oxigen concentration). Data is transmitted to central
unit that again publishs the data and makes it available to a
doctor or health care center.
Emergency Alerts
Devices measure environment, transmit data to central unit to
publish it. Authenticated entities subscribe to data for
emergency warnings (e.g. earth quake warning system, fire
department).
Logistics
Logistic devices are equipped with sensors (e.g., graviation,
humidity, GPS). Data is monitored and made available to owners to
locate the equipment during transportation.
Several use-cases are specified in reference [12]. All use-cases
have in common that data is collected to monitor something, is
transmitted to central unit that published data. This data can than
be accessed by authorized entities (e.g., device, persons). Usually,
the data includes sensitive information and, therefore, secure
transmission is required as proposed by the aforementioned sections.
The projects FLAMINGO [9] and SmartenIT [8] deal with some of those
use-cases and investigate the security issues with focus on two-way
authentication issues for secure data transmission.
5.2. Requirements
In order to show the applicability of the proposed solution
throughout the above sections a common network structure consisting
of a global sink and several sensor nodes is assumed. Additionally,
an Access Control Server (ACS) is integrated into the network. The
ACS is a trusted entity and a more resource-rich server, on which the
access rights for the publishers (= sensor nodes) of the secured
network are stored. Therefore, every publisher in the network MUST
have an unique identity. Figure 4 illustrates the assumed
architecture, where it is assumed that also the subscriber,
publisher, and sensors have individual certificates received from the
Certificate Authority. Depending on individual architectural setups
it can be possible to integrate the ACS functionality direct into the
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gateway.
+----------------------------+
| Certificate Authority (CA) |
+----------------------------+
| |
+----------------+ +----------------------------+ +---------+
| Subscriber (S) |-----| Access Control Server (ACS)|----| Gateway |
+----------------+ +----------------------------+ +---------+
|
+---------------+
| Publisher (P) |
+---------------+
|
+------------+----------------+
| | |
+----------+ +----------+ +----------+
| Sensor 1 | | Sensor 2 | ... | Sensor n |
+----------+ +----------+ +----------+
Figure 4: Architecture
As mentioned the concept of Internet of Things forms the basis for
this draft, which include also the basic understanding of the
Internet. Thus, it is assumed that identities are usually
established via public key cryptography and the identifiers provided
through X.509 certificates [RFC5280]. In general, X.509 certificate
contains the public key of an entity and its common name. A trusted
third party - Certificate Authority (CA) - signs that certificate.
This signing allows the receiver to detect modifications to the
certificate and that the identity of the entity, who requested the
certificate, has been verified by the CA. The CA can be run by the
administrator of the network or an established Internet certificate
authority can be used.
Furthermore, it is assumed that the identity of a default subscriber
is usually preconfigured on a publisher before it is deployed.
5.3. Data Access Procedure
Based on the FLAMINGO project the following use-case is assumed [9]:
A sensor node has published its data, which is transmitted in
direction to the global sink (cf. Figure 4 where global sink is
located in the gateway component). Therefore, it is assumed that a
two-way authentication handshake between those two communication
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parties was successful performed before. In between the data can be
cashed in order to make it accessible more quicker to subscribers.
In this case the cached entity functions as a publisher.
Assuming the new subscriber wants to access the data, it must
initialize a connection with the publisher. Therefore, the
subscriber MUST obtain an access ticket from the ACS before. The
functionality of the ACS is to verify that the subscriber has the
right to access the data available from the publisher. Those rights
are influenced by legal and regulative implications (e.g., rights
connected to an ISP region, where the subscriber belongs to). If the
subscriber received a valid access ticket, it is presented to the
publisher. The publisher must evaluate the identity of the
subscriber and verify the ticket it has received from the ACS.
If the validation was successful the subscriber can access the data.
Before every kind of data exchange, where sensitive information is
involved, takes place the proposed two-way authentication handshake
is performed in order to establish a highly secured communication
channel between the entities. Figure 5 summarizes the aforementioned
work flow and will be defined in detail in the upcoming subsections
assuming that the ACS functionality is included in the Gateway
component.
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Subscriber (S) Gateway (incl. ACS) Publisher (P)
| | |
| | Two-way |
| |<-------Authentication Handshake---->|
| | |
| |<------Measured Data-----------------|
| | |
| Two-way | |
|<--authentication Handshake -->| |
| | |
|---Connection request for P--->| |
| | |
| Check of Request |
| | |
|<---Copy of Access Ticket------+-----Subscriber's Access ticket----->|
| | |
| | Validation of
| | Access Ticket
| | |
| Two-way authentication handshake between |
|<------------------------------------------------------------------->|
| Subscriber and Publisher |
| | |
|<-------------Data exchange using DTLS secured channel-------------->|
| | |
| | |
Figure 5: Flow Diagram for Data Access Procedure
6. Hardware Requirements
6.1. Class 2 Hardware Requirements
Hu et al. showed that RSA, the most commonly used public key
algorithm in the Internet, can be used in sensor networks with the
assistance of a class 2 devices that MAY include a TPM, which costs
less than 5% of a common sensor node [4]. A TPM is an embedded chip
that provides tamper proof generation and storage of RSA keys as well
as hardware support for the RSA algorithm. The certificate of a TPM
equipped publisher and the certificate of a trusted CA MUST be stored
on the publisher prior to deployment.
For publishers that are not equipped with TPM chips the
authentication can be proposed via the DTLS pre-shared key cipher-
suite, which requires a small number of random bytes, from which the
actual key is derived, to be preloaded to the publisher before
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deployment. This secret MUST also be made available to the ACS,
which will disclose the key to devices with sufficient authorization.
6.2. Class 1 Hardware Requirements
No hardware requirements.
7. Security Considerations
7.1. Class 2 Security Considerations
The following security goals are addressed by the key idea presented
in this draft:
Authenticity
Recipients of a message can identify their communication partners
and can detect if the sender information has been forged.
Integrity
Communication partners can detect changes to a message during
transmission.
Confidentiality
Attackers cannot gain knowledge about the content of a secured
message.
By choosing DTLS as the security protocol those goals can be
achieved. DTLS is a modification of TLS for the unreliable UDP and
inherits its security properties [5]. Furthermore, if hardware
including TPM is available, it is recommended to use it especially on
vulnerable points (e.g., cluster heads, aggregation points,
publisher, subscriber) within the network.
7.2. Class 1 Security Considerations
t.b.a.
8. IANA Considerations
No considerations.
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9. Acknowledgement
The draft authors thank Thomas Kothmayr from Technische Universitaet
Muenchen (Germany) for developing the idea of the DTLS solution.
Additional thanks to Wen Hu from CSIRO ICT Centre (Australia), who
supported the complete approach and funding the required sensor
node`s hardware with TPM technology.
The ongoing work is supported partially by the SmartenIT [8] and the
FLAMINGO [9] projects, funded by the EU FP7 Program under Contract
No. FP7-2012-ICT-317846 and No. FP7-2012-ICT-318488, respectively.
10. Formal Syntax
6LoWPAN - IPv6 over Low power Wireless Personal Area Network (RFC
4944)
ACS - Access Control Server
BLIP - Berkeley Low-power IP stack
CA - Certificate Authority
COAP - Constrained Application Protocol
DTLS - Datagram Transport Layer Security protocol (RFC 6347)
ECC - Elliptic Curve Cryptography
ECDH - Elliptic Curve Diffie-Hellman
ECDSA -Elliptic Curve Digital Signature Algorithm
ECIES - Elliptic Curve Integrated Encryption System
ETSI - European Telecommunications Standard Institute
HVAC - Heating, Ventilation, and Air Conditioning
IEC - Integrated Encryption Scheme
IoT - Internet of Things
KiB - Kibi-Byte (1 KiB = 1024 Bytes) [14]
PKC - Public Key Cryptography
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PSK - Pre-shared Key
RPL - Routing Protocol for Low power and Lossy Networks (RFC 6550)
TCP - Transmission Control Protocol (RFC 793)
TLS - The Transport Layer Security (TLS) Protocol Version 1.2 (RFC
5246)
TPM - Trusted Platform Module
UDP - User Datagram Protocol (RFC 768)
WSN - Wireless Sensor Network
11. References
11.1. Norminative References
[RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for
Constrained-Node Networks", RFC 7228, May 2014.
[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.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, January 2012.
[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, September 2007.
[RFC6090] McGrew, D., Igoe, K., and M. Salter, "Fundamental Elliptic
Curve Cryptography Algorithms", RFC 6090, February 2011.
[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.
[RFC4754] Fu, D. and J. Solinas, "IKE and IKEv2 Authentication Using
the Elliptic Curve Digital Signature Algorithm (ECDSA)",
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RFC 4754, January 2007.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252, June 2014.
[3] Balakrishnan, H., Padmanabhan, V., Seshan, S., and R.
Katz, "A Comparison Of Mechanisms For Improving TCP
Performance Over Wireless Links", IEEE/ACM Transaction on
Networking, Vol. 5, No. 6, pp. 756-769 , 1997.
[5] Modadugu et al., N., "The Design and Implementation of
Datagram TLS", In Proceedings of the Network and
Distributed System Security Symposium (NDSS), San Diego,
California, U.S.A. , 2004.
[12] Seitz et al., L., "ACE use cases,
https://tools.ietf.org/html/draft-seitz-ace-usecases-02",
IETF Draft draft-ietf-ace-usecases-02, Version 2 , 2014.
11.2. Informative References
[1] LeHong, H., "Hype Cycle for the Internet of Things", Tech.
rep., Gartner Inc. , 2012.
[4] Hu, W., "Toward Trusted Wireless Sensor Networks", ACM
Transactions on Sensor Networks, Vol. 7, No.5. , 2010.
[6] Kothmayr et al., T., "DTLS Based Security and Two-Way
Authentication for the Internet of Things", Elsevier,
Journal Ad Hoc Networks , 2013.
[7] Dawson-Haggerty, S. and D. Culler, "Berkeley IP
Information, Berkeley WEBS Wireless Embedded Systems,
http://smote.cs.berkeley.edu:8000/tracenv/wiki/blip",
2010.
[8] SmartenIT Consortium, "Socially-aware Management of New
Overlay Application Traffic combined with Energy
Efficiency in the Internet (SmartenIT),
http://www.smartenit.eu/", 2013.
[9] Flamingo Consortium, "FLAMINGO - Management of the Future
Internet, http://www.fp7-flamingo.eu/", 2013.
[10] Schmitt, C., "Secure Data Transmission in Wireless Sensor
Networks, Dissertation", Network Architectures and
Services (NET), ISBN: 3-937201-36-X, ISSN: 1868-2634
(print), DOI: 10.2313/NET-2013-07-2 , 2013.
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[11] Boyd, C. and A. Mathuria, "Protocols for Authentication
and Key Establishment (Information Security and
Cryptography)", Springer, ISBN 3540431071 , 2003.
[13] "OpenSSL - Cryptography and SSL/TLS Toolkit,
https://www.openssl.org/", 2014.
[14] "International Standard - Quantities and units - Part 13:
Information science and technology", IEC 80000-13 , 2008.
[15] Bellare, M., Canetti, R., and H. Krawczyk, "A Modular
Approach to the Design and Analysis of Authentication and
Key Exchange Protocols (Extended Abstract)", In
Proceedings of the 13th Annual ACM Symposium on Theory of
Computing, ser. STOC , 2008.
[16] Menezes, A., van Oorschot, P., and S. Vanstone, "Handbook
of Applied Cryptography", ICRC Press, ISBN:
0-8493-8523-7 , 1996.
[2] Noack, M., "Optimization of Two-way Authentication
Protocol in Internet of Things", Master Thesis, University
of Zurich, Communication Systems Group, Department of
Informatics, Zurich, Switzerland , 2014.
Authors' Addresses
Corinna Schmitt
University of Zurich
Department for Informatics
Communication Systems Group
Binzmuehlestrasse 14
Zurich 8050
Switzerland
Email: schmitt@ifi.uzh.ch
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Burkhard Stiller
University of Zurich
Department for Informatics
Communication Systems Group
Binzmuehlestrasse 14
Zurich 8050
Switzerland
Email: stiller@ifi.uzh.ch
Martin Noack
Email: martin.noack@acm.org
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