Internet DRAFT - draft-seitz-ace-oscoap-profile
draft-seitz-ace-oscoap-profile
ACE Working Group L. Seitz
Internet-Draft RISE SICS AB
Intended status: Standards Track F. Palombini
Expires: April 28, 2018 Ericsson AB
M. Gunnarsson
RISE SICS AB
October 25, 2017
OSCORE profile of the Authentication and Authorization for Constrained
Environments Framework
draft-seitz-ace-oscoap-profile-06
Abstract
This memo specifies a profile for the Authentication and
Authorization for Constrained Environments (ACE) framework. It
utilizes Object Security for Constrained RESTful Environments
(OSCORE) to provide communication security, server authentication,
and proof-of-possession for a key owned by the client and bound to an
OAuth 2.0 access token.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on April 28, 2018.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. Client to Resource Server . . . . . . . . . . . . . . . . . . 3
2.1. Signaling the use of OSCORE . . . . . . . . . . . . . . . 3
2.2. Key establishment for OSCORE . . . . . . . . . . . . . . 4
3. Client to Authorization Server . . . . . . . . . . . . . . . 6
4. Resource Server to Authorization Server . . . . . . . . . . . 7
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7
6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 7
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1. Normative References . . . . . . . . . . . . . . . . . . 7
8.2. Informative References . . . . . . . . . . . . . . . . . 8
Appendix A. Profile Requirements . . . . . . . . . . . . . . . . 9
Appendix B. Using the pop-key with EDHOC (EDHOC+OSCORE) . . . . 10
B.1. Using Asymmetric Keys . . . . . . . . . . . . . . . . . . 10
B.2. Using Symmetric Keys . . . . . . . . . . . . . . . . . . 12
B.3. Processing . . . . . . . . . . . . . . . . . . . . . . . 13
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
This memo specifies a profile of the ACE framework
[I-D.ietf-ace-oauth-authz]. In this profile, a client and a resource
server use CoAP [RFC7252] to communicate. The client uses an access
token, bound to a key (the proof-of-possession key) to authorize its
access to the resource server. In order to provide communication
security, proof of possession, and server authentication they use
Object Security for Constrained RESTful Environments (OSCORE)
[I-D.ietf-core-object-security]. Optionally the client and the
resource server may also use CoAP and OSCORE to communicate with the
authorization server.
OSCORE specifies how to use CBOR Object Signing and Encryption (COSE)
[RFC8152] to secure CoAP messages. In order to provide replay and
reordering protection OSCORE also introduces sequence numbers that
are used together with COSE.
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Note that OSCORE can be used to secure CoAP messages, as well as HTTP
and combinations of HTTP and CoAP; a profile of ACE similar to the
one described in this document, with the difference of using HTTP
instead of CoAP as communication protocol, could be specified
analogously to this one.
1.1. 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]. These
words may also appear in this document in lowercase, absent their
normative meanings.
Certain security-related terms such as "authentication",
"authorization", "confidentiality", "(data) integrity", "message
authentication code", and "verify" are taken from [RFC4949].
Since we describe exchanges as RESTful protocol interactions HTTP
[RFC7231] offers useful terminology.
Terminology for entities in the architecture is defined in OAuth 2.0
[RFC6749] and [I-D.ietf-ace-actors], such as client (C), resource
server (RS), and authorization server (AS). It is assumed in this
document that a given resource on a specific RS is associated to a
unique AS.
2. Client to Resource Server
The use of OSCORE for arbitrary CoAP messages is specified in
[I-D.ietf-core-object-security]. This section defines the specific
uses and their purpose for securing the communication between a
client and a resource server, and the parameters needed to negotiate
the use of this profile with the token resource at the authorization
server as specified in section 5.5 of the ACE framework
[I-D.ietf-ace-oauth-authz].
2.1. Signaling the use of OSCORE
A client requests a token at an AS via the /token resource. This
follows the message formats specified in section 5.5.1 of the ACE
framework [I-D.ietf-ace-oauth-authz].
The AS responding to a successful access token request as defined in
section 5.5.2 of the ACE framework can signal that the use of OSCORE
is REQUIRED for a specific access token by including the "profile"
parameter with the value "coap_oscore" in the access token response.
This means that the client MUST use OSCORE towards all resource
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servers for which this access token is valid, and follow Section 2.2
to derive the security context to run OSCORE.
The error response procedures defined in section 5.5.3 of the ACE
framework are unchanged by this profile.
Note the the client and the authorization server MAY OPTIONALLY use
OSCORE to protect the interaction via the /token resource. See
Section 3 for details.
2.2. Key establishment for OSCORE
Section 3.2 of OSCORE [I-D.ietf-core-object-security] defines how to
derive a security context based on a shared master secret and a set
of other parameters, established between client and server. The
proof-of-possession key (pop-key) provisioned from the AS MAY, in
case of pre-shared keys, be used directly as master secret in OSCORE.
If OSCORE is used directly with the symmetric pop-key as master
secret, then the AS MUST provision the following data, in response to
the access token request:
o a master secret
o the sender identifier
o the recipient identifier
Additionally, the AS MAY provision the following data, in the same
response. In case these parameters are omitted, the default values
are used as described in section 3.2 of
[I-D.ietf-core-object-security].
o an AEAD algorithm
o a KDF algorithm
o a salt
o a replay window type and size
The master secret MUST be communicated as COSE_Key in the 'cnf'
parameter of the access token response as defined in section 5.5.4.5
of [I-D.ietf-ace-oauth-authz]. The AEAD algorithm MAY be included as
the 'alg' parameter in the COSE_Key; the KDF algorithm MAY be
included as the 'kdf' parameter of the COSE_Key and the salt MAY be
included as the 'slt' parameter of the COSE_Key as defined in table
1. The same parameters MUST be included as metadata of the access
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token; if the token is a CWT [I-D.ietf-ace-cbor-web-token], the same
COSE_Key structure MUST be placed in the 'cnf' claim of this token.
The AS MUST also assign identifiers to both client and RS, which are
then used as Sender ID and Recipient ID in the OSCORE context as
described in section 3.1 of [I-D.ietf-core-object-security]. These
identifiers MUST be unique in the set of all clients and RS
identifiers for a certain AS. Moreover, these MUST be included in
the COSE_Key as header parameters, as defined in table 1.
We assume in this document that a resource is associated to one
single AS, which makes it possible to assume unique identifiers for
each client requesting a particular resource to a RS. If this is not
the case, collisions of identifiers may appear in the RS, in which
case the RS needs to have a mechanism in place to disambiguate
identifiers or mitigate their effect.
Note that C should set the Sender ID of its security context to the
clientId value received and the Recipient ID to the serverId value,
and RS should do the opposite.
+----------+-------+--------------+------------+-------------------+
| name | label | CBOR type | registry | description |
+----------+-------+--------------+------------+-------------------+
| clientId | TBD | bstr | | Identifies the |
| | | | | client in an |
| | | | | OSCORE context |
| | | | | using this key |
| | | | | |
| serverId | TBD | bstr | | Identifies the |
| | | | | server in an |
| | | | | OSCORE context |
| | | | | using this key |
| | | | | |
| kdf | TBD | bstr | | Identifies the |
| | | | | KDF algorithm in |
| | | | | an OSCORE context |
| | | | | using this key |
| | | | | |
| slt | TBD | bstr | | Identifies the |
| | | | | master salt in |
| | | | | an OSCORE context |
| | | | | using this key |
+----------+-------+--------------+------------+-------------------+
Table 1: Additional common header parameters for COSE_Key
Figure 1 shows an example of such an AS response, in CBOR diagnostic
notation without the tag and value abbreviations.
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Header: Created (Code=2.01)
Content-Type: "application/cose+cbor"
Payload:
{
"access_token" : b64'SlAV32hkKG ...
(remainder of access token omitted for brevity)',
"profile" : "coap_oscore",
"expires_in" : "3600",
"cnf" : {
"COSE_Key" : {
"kty" : "Symmetric",
"alg" : "AES-CCM-16-64-128",
"clientId" : b64'qA',
"serverId" : b64'Qg',
"k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
}
}
}
Figure 1: Example AS response with OSCORE parameters.
Figure 2 shows an example CWT, containing the necessary OSCORE
parameters in the 'cnf' claim, in CBOR diagnostic notation without
tag and value abbreviations.
{
"aud" : "tempSensorInLivingRoom",
"iat" : "1360189224",
"exp" : "1360289224",
"scope" : "temperature_g firmware_p",
"cnf" : {
"COSE_Key" : {
"kty" : "Symmetric",
"alg" : "AES-CCM-16-64-128",
"clientId" : b64'Qg',
"serverId" : b64'qA',
"k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
}
}
Figure 2: Example CWT with OSCORE parameters.
3. Client to Authorization Server
As specified in the ACE framework section 5.5
[I-D.ietf-ace-oauth-authz], the Client and AS can also use CoAP
instead of HTTP to communicate via the token resource. This section
specifies how to use OSCORE between Client and AS together with CoAP.
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The use of OSCORE for this communication is OPTIONAL in this profile,
other security protocols (such as DTLS) MAY be used instead.
The client and the AS are expected to have pre-established security
contexts in place. How these security contexts are established is
out of scope for this profile. Furthermore the client and the AS
communicate using OSCORE ([I-D.ietf-core-object-security]) through
the introspection resource as specified in section 5.6 of
[I-D.ietf-ace-oauth-authz].
4. Resource Server to Authorization Server
As specified in the ACE framework section 5.6
[I-D.ietf-ace-oauth-authz], the RS and AS can also use CoAP instead
of HTTP to communicate via the introspection resource. This section
specifies how to use OSCORE between RS and AS. The use of OSCORE for
this communication is OPTIONAL in this profile, other security
protocols (such as DTLS) MAY be used instead.
The RS and the AS are expected to have pre-established security
contexts in place. How these security contexts are established is
out of scope for this profile. Furthermore the RS and the AS
communicate using OSCORE ([I-D.ietf-core-object-security]) through
the introspection resource as specified in section 5.6 of
[I-D.ietf-ace-oauth-authz].
5. Security Considerations
TBD.
6. Privacy Considerations
TBD.
7. IANA Considerations
TBD. 'coap_oscore' as profile id. Header parameters 'sid', 'rid',
'kdf' and 'slt' for COSE_Key.
8. References
8.1. Normative References
[I-D.ietf-ace-cbor-web-token]
Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
"CBOR Web Token (CWT)", draft-ietf-ace-cbor-web-token-08
(work in progress), August 2017.
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[I-D.ietf-ace-oauth-authz]
Seitz, L., Selander, G., Wahlstroem, E., Erdtman, S., and
H. Tschofenig, "Authentication and Authorization for
Constrained Environments (ACE)", draft-ietf-ace-oauth-
authz-07 (work in progress), August 2017.
[I-D.ietf-core-object-security]
Selander, G., Mattsson, J., Palombini, F., and L. Seitz,
"Object Security for Constrained RESTful Environments
(OSCORE)", draft-ietf-core-object-security-05 (work in
progress), September 2017.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014,
<https://www.rfc-editor.org/info/rfc7252>.
[RFC8152] Schaad, J., "CBOR Object Signing and Encryption (COSE)",
RFC 8152, DOI 10.17487/RFC8152, July 2017,
<https://www.rfc-editor.org/info/rfc8152>.
8.2. Informative References
[I-D.gerdes-ace-dcaf-authorize]
Gerdes, S., Bergmann, O., and C. Bormann, "Delegated CoAP
Authentication and Authorization Framework (DCAF)", draft-
gerdes-ace-dcaf-authorize-04 (work in progress), October
2015.
[I-D.ietf-ace-actors]
Gerdes, S., Seitz, L., Selander, G., and C. Bormann, "An
architecture for authorization in constrained
environments", draft-ietf-ace-actors-05 (work in
progress), March 2017.
[I-D.selander-ace-cose-ecdhe]
Selander, G., Mattsson, J., and F. Palombini, "Ephemeral
Diffie-Hellman Over COSE (EDHOC)", draft-selander-ace-
cose-ecdhe-07 (work in progress), July 2017.
[RFC4949] Shirey, R., "Internet Security Glossary, Version 2",
FYI 36, RFC 4949, DOI 10.17487/RFC4949, August 2007,
<https://www.rfc-editor.org/info/rfc4949>.
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[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.
[RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
October 2013, <https://www.rfc-editor.org/info/rfc7049>.
[RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
DOI 10.17487/RFC7231, June 2014,
<https://www.rfc-editor.org/info/rfc7231>.
Appendix A. Profile Requirements
This section lists the specifications on this profile based on the
requirements on the framework, as requested in Appendix C. of
[I-D.ietf-ace-oauth-authz].
o (Optional) discovery process of how the client finds the right AS
for an RS it wants to send a request to: Not specified
o communication protocol the client and the RS must use: CoAP
o security protocol the client and RS must use: OSCORE
o how the client and the RS mutually authenticate: Implicitly by
possession of a common OSCORE security context
o Content-format of the protocol messages: "application/cose+cbor"
o proof-of-possession protocol(s) and how to select one; which key
types (e.g. symmetric/asymmetric) supported: OSCORE algorithms;
pre-established symmetric keys
o profile identifier: coap_oscore
o (Optional) how the RS talks to the AS for introspection: HTTP/CoAP
(+ TLS/DTLS/OSCORE)
o how the client talks to the AS for requesting a token: HTTP/CoAP
(+ TLS/DTLS/OSCORE)
o how/if the /authz-info endpoint is protected: Security protocol
above
o (Optional)other methods of token transport than the /authz-info
endpoint: no
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Appendix B. Using the pop-key with EDHOC (EDHOC+OSCORE)
EDHOC specifies an authenticated Diffie-Hellman protocol that allows
two parties to use CBOR [RFC7049] and COSE in order to establish a
shared secret key with perfect forward secrecy. The use of Ephemeral
Diffie-Hellman Over COSE (EDHOC) [I-D.selander-ace-cose-ecdhe] in
this profile in addition to OSCORE, provides perfect forward secrecy
(PFS) and the initial proof-of-possession, which ties the proof-of-
possession key to an OSCORE security context.
If EDHOC is used together with OSCORE, and the pop-key (symmetric or
asymmetric) is used to authenticate the messages in EDHOC, then the
AS MUST provision the following data, in response to the access token
request:
o a symmetric or public key (associated to the RS)
o a key identifier;
How these parameters are communicated depends on the type of key
(asymmetric or symmetric). Moreover, the AS MUST signal the use of
OSCORE + EDHOC with the 'profile' parameter set to
"coap_oscore_edhoc" and follow Appendix B to derive the security
context to run OSCORE.
Note that in the case described in this section, the 'expires_in'
parameter, defined in section 4.2.2. of [RFC6749] defines the
lifetime in seconds of both the access token and the shared secret.
After expiration, C MUST acquire a new access token from the AS, and
run EDHOC again, as specified in this section
B.1. Using Asymmetric Keys
In case of an asymmetric key, C MUST communicate its own asymmetric
key to the AS in the 'cnf' parameter of the access token request, as
specified in section 5.5.1 of [I-D.ietf-ace-oauth-authz]; the AS MUST
communicate the RS's public key to C in the response, in the 'rs_cnf'
parameter, as specified in section 5.5.1 of
[I-D.ietf-ace-oauth-authz]. Note that the RS's public key MUST
include a 'kid' parameter, and that the value of the 'kid' MUST be
included in the access token, to let the RS know which of its public
keys C used. If the access token is a CWT
[I-D.ietf-ace-cbor-web-token], the key identifier MUST be placed
directly in the 'cnf' structure (if the key is only referenced).
Figure 3 shows an example of such a request in CBOR diagnostic
notation without tag and value abbreviations.
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Header: POST (Code=0.02)
Uri-Host: "server.example.com"
Uri-Path: "token"
Content-Type: "application/cose+cbor"
Payload:
{
"grant_type" : "client_credentials",
"cnf" : {
"COSE_Key" : {
"kid" : "client_key"
"kty" : "EC",
"crv" : "P-256",
"x" : b64'usWxHK2PmfnHKwXPS54m0kTcGJ90UiglWiGahtagnv8',
"y" : b64'IBOL+C3BttVivg+lSreASjpkttcsz+1rb7btKLv8EX4'
}
}
}
Figure 3: Example access token request (OSCORE+EDHOC, asymmetric).
Figure 4 shows an example of a corresponding response in CBOR
diagnostic notation without tag and value abbreviations.
Header: Created (Code=2.01)
Content-Type: "application/cose+cbor"
Payload:
{
"access_token" : b64'SlAV32hkKG ...
(contains "kid" : "client_key")',
"profile" : "coap_oscore_edhoc",
"expires_in" : "3600",
"cnf" : {
"COSE_Key" : {
"kid" : "server_key"
"kty" : "EC",
"crv" : "P-256",
"x" : b64'cGJ90UiglWiGahtagnv8usWxHK2PmfnHKwXPS54m0kT',
"y" : b64'reASjpkttcsz+1rb7btKLv8EX4IBOL+C3BttVivg+lS'
}
}
}
Figure 4: Example AS response (EDHOC+OSCORE, asymmetric).
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B.2. Using Symmetric Keys
In the case of a symmetric key, the AS MUST communicate the key to
the client in the 'cnf' parameter of the access token response, as
specified in section 5.5.2. of [I-D.ietf-ace-oauth-authz]. AS MUST
also select a key identifier, that MUST be included as the 'kid'
parameter either directly in the 'cnf' structure, as in figure 4 of
[I-D.ietf-ace-oauth-authz], or as the 'kid' parameter of the
COSE_key, as in figure 6 of [I-D.ietf-ace-oauth-authz].
Figure 5 shows an example of the necessary parameters in the AS
response to the access token request when EDHOC is used. The example
uses CBOR diagnostic notation without tag and value abbreviations.
Header: Created (Code=2.01)
Content-Type: "application/cose+cbor"
Payload:
{
"access_token" : b64'SlAV32hkKG ...
(remainder of access token omitted for brevity)',
"profile" : "coap_oscore_edhoc",
"expires_in" : "3600",
"cnf" : {
"COSE_Key" : {
"kty" : "Symmetric",
"kid" : b64'5tOS+h42dkw',
"k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
}
}
}
Figure 5: Example AS response (EDHOC+OSCORE, symmetric).
In both cases, the AS MUST also include the same key identifier as
'kid' parameter in the access token metadata. If the access token is
a CWT [I-D.ietf-ace-cbor-web-token], the key identifier MUST be
placed inside the 'cnf' claim as 'kid' parameter of the COSE_Key or
directly in the 'cnf' structure (if the key is only referenced).
Figure 6 shows an example CWT containing the necessary EDHOC+OSCORE
parameters in the 'cnf' claim, in CBOR diagnostic notation without
tag and value abbreviations.
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{
"aud" : "tempSensorInLivingRoom",
"iat" : "1360189224",
"exp" : "1360289224",
"scope" : "temperature_g firmware_p",
"cnf" : {
"COSE_Key" : {
"kty" : "Symmetric",
"kid" : b64'5tOS+h42dkw',
"k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
}
}
Figure 6: Example CWT with EDHOC+OSCORE, symmetric case.
All other parameters defining OSCORE security context are derived
from EDHOC message exchange, including the master secret (see
Appendix C.2 of [I-D.selander-ace-cose-ecdhe]).
B.3. Processing
To provide forward secrecy and mutual authentication in the case of
pre-shared keys, pre-established raw public keys or with X.509
certificates it is RECOMMENDED to use EDHOC
[I-D.selander-ace-cose-ecdhe] to generate the keying material. EDHOC
MUST be used as defined in Appendix C of
[I-D.selander-ace-cose-ecdhe], with the following additions and
modifications.
The first EDHOC message is sent after the access token is posted to
the /authz-info resource of the RS as specified in section 5.7.1 of
[I-D.ietf-ace-oauth-authz]. Then the EDHOC message_1 is sent and the
EDHOC protocol is initiated [I-D.selander-ace-cose-ecdhe]).
Before the RS continues with the EDHOC protocol and responds to this
token submission request, additional verifications on the access
token are done: the RS SHALL process the access token according to
[I-D.ietf-ace-oauth-authz]. If the token is valid then the RS
continues processing EDHOC following Appendix C of
[I-D.selander-ace-cose-ecdhe], otherwise it discontinues EDHOC and
responds with the error code as specified in
[I-D.ietf-ace-oauth-authz].
o In case the EDHOC verification fails, the RS MUST return an error
response to the client with code 4.01 (Unauthorized).
o If RS has an access token for C but not for the resource that C
has requested, RS MUST reject the request with a 4.03 (Forbidden).
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o If RS has an access token for C but it does not cover the action C
requested on the resource, RS MUST reject the request with a 4.05
(Method Not Allowed).
o If all verifications above succeeds, further communication between
client and RS is protected with OSCORE, including the RS response
to the OSCORE request.
In the case of EDHOC being used with symmetric keys, the protocol in
section 5 of [I-D.selander-ace-cose-ecdhe] MUST be used. If the key
is asymmetric, the RS MUST also use an asymmetric key for
authentication. This key is known to the client through the access
token response (see section 5.5.2 of the ACE framework). In this
case the protocol in section 4 of [I-D.selander-ace-cose-ecdhe] MUST
be used.
Figure 7 illustrates the message exchanges for using OSCORE+EDHOC
(step C in figure 1 of [I-D.ietf-ace-oauth-authz]).
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Resource
Client Server
| |
| |
+--------->| Header: POST (Code=0.02)
| POST | Uri-Path:"authz-info"
| | Content-Type: application/cbor
| | Payload: access token
| |
| |
+--------->| Header: POST (Code=0.02)
| POST | Uri-Path: "/.well-known/edhoc"
| | Content-Type: application/edhoc
| | Payload: EDHOC message_1
| |
|<---------+ Header: 2.04 Changed
| 2.04 | Content-Type: application/edhoc
| | Payload: EDHOC message_2
| |
+--------->| Header: POST (Code=0.02)
| POST | Uri-Path: "/.well-known/edhoc"
| | Content-Type: application/edhoc
| | Payload: EDHOC message_3
| |
|<---------+ Header: 2.04 Changed
| 2.04 |
| |
start of protected communication
| |
+--------->| CoAP request +
| OSCORE | Object-Security option
| request |
| |
|<---------+ CoAP response +
| OSCORE | Object-Security option
| response |
| |
Figure 7: Access token and key establishment with EDHOC
Acknowledgments
The authors wish to thank Jim Schaad, Goeran Selander and Marco
Tiloca for the input on this memo. The error responses specified in
Appendix B.3 were originally specified by Gerdes et al. in
[I-D.gerdes-ace-dcaf-authorize].
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Authors' Addresses
Ludwig Seitz
RISE SICS AB
Scheelevagen 17
Lund 22370
SWEDEN
Email: ludwig.seitz@ri.se
Francesca Palombini
Ericsson AB
Farogatan 6
Kista SE-16480 Stockholm
Sweden
Email: francesca.palombini@ericsson.com
Martin Gunnarsson
RISE SICS AB
Scheelevagen 17
Lund 22370
SWEDEN
Email: martin.gunnarsson@ri.se
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