draft-seitz-ace-oscoap-profile.nroff

.pl 10.0i
.po 0
.ll 7.2i
.lt 7.2i
.nr LL 7.2i
.nr LT 7.2i
.ds LF Seitz, L.
.ds RF FORMFEED[Page %]
.ds LH INTERNET DRAFT
.ds RH June 30, 2017
.ds CH OSCOAP profile of ACE
.ds CF Expires January 1, 2018
.hy 0
.nh
.ad l
.in 0

.nf
.tl 'ACE Working Group''L. Seitz'
.tl 'Internet-Draft''M. Gunnarsson'
.tl 'Intended Status: Standards Track''RISE SICS AB'
.tl 'Expires: January 1, 2018''F. Palombini'
.tl '''Ericsson AB'
.tl '''June 30, 2017'
.fi

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.ce 2
OSCOAP profile of ACE
draft-seitz-ace-oscoap-profile-03
.fi


.in 3
.ti 0
Abstract
 
This memo specifies a profile for the ACE framework for Authentication and Authorization.  It utilizes Object Security of CoAP (OSCOAP) and
Ephemeral Diffie-Hellman over COSE (EDHOC) 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.

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Status of this Memo

This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP\078 and BCP\079.

Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups.  Note that other groups may also distribute working documents as \%Internet-Drafts.

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The list of current Internet-Drafts can be accessed at \%http://www.ietf.org/1id-abstracts.html

The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html


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This document is subject to BCP\078 and the IETF Trust's Legal Provisions Relating to IETF Documents \%(http://trustee.ietf.org/license-info) in effect on the date of publication of this document.  Please review these documents carefully, as they describe your rights and restrictions with respect to this document.  Code Components extracted from this document must include Simplified BSD License text as described in Section\04.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.



.\" \# TD4  -- Set TOC depth by altering this value (TD5 = depth 5)
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Table of Contents

.nf
   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1  Terminology . . . . . . . . . . . . . . . . . . . . . . . .  3
   2. Client to Resource Server . . . . . . . . . . . . . . . . . . .  4
     2.1. Signaling the use of OSCOAP . . . . . . . . . . . . . . . .  4
     2.2. Key establishment for OSCOAP  . . . . . . . . . . . . . . .  4
       2.2.1 Using the pop-key with OSCOAP directly (OSCOAP)  . . . .  4
       2.2.1 Using the pop-key with EDHOC (EDHOC+OSCOAP)  . . . . . .  7
   3. Client to Authorization Server  . . . . . . . . . . . . . . . . 12
   4. Resource Server to Authorization Server . . . . . . . . . . . . 12
   5. Security Considerations . . . . . . . . . . . . . . . . . . . . 13
   6. Privacy Considerations  . . . . . . . . . . . . . . . . . . . . 13
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
   8.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 13
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     9.1  Normative References  . . . . . . . . . . . . . . . . . . . 13
     9.2  Informative References  . . . . . . . . . . . . . . . . . . 14
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 14
.fi
.in 3

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.bp
.ti 0
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 of CoAP (OSCOAP) [I-D.ietf-core-object-security] and Ephemeral Diffie-Hellman Over COSE (EDHOC) [I-D.selander-ace-cose-ecdhe].  Optionally the client and the resource server may also use CoAP and OSCOAP to communicate with the authorization server.  The use of EDHOC in this profile in addition to OSCOAP, provides perfect forward secrecy (PFS) and the initial proof-of-possession, which ties the proof-of-possession key to an OSCOAP security context.

OSCOAP specifies how to use CBOR Object Signing and Encryption (COSE) [I-D.ietf-cose-msg] to secure CoAP messages.  In order to provide replay and reordering protection OSCOAP also introduces sequence numbers that are used together with COSE.  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.

.ti 0
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).

Note that the term "endpoint" is used here following its OAuth definition, which is to denote resources such as /token and /introspect at the AS and /authz-info at the RS.  The CoAP [RFC7252] definition, which is "An entity participating in the CoAP protocol" is not used in this memo.


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2. Client to Resource Server

The use of OSCOAP 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 endpoint at the authorization server as specified in section 5.5 of the ACE framework [I-D.ietf-ace-oauth-authz].

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2.1. Signaling the use of OSCOAP

A client requests a token at an AS via the /token endpoint.  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 OSCOAP is REQUIRED for a specific access token by including the "profile" parameter with the value "coap_oscoap" in the access token response.  This means that the client MUST use OSCOAP towards all resource servers for which this access token is valid.

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 OSCOAP to protect the interaction via the /token endpoint. See section 3 for details.

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2.2. Key establishment for OSCOAP

Section 3.2 of OSCOAP [I-D.ietf-core-object-security] defines how to derive a security context based on a symmetric master secret and a few 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 OSCOAP.  Alternatively the pop-key (symmetric or asymmetric) MAY be used to authenticate the messages in the key exchange protocol EDHOC [I-D.selander-ace-cose-ecdhe], from which a master secret is derived.

.ti 0
2.2.1 Using the pop-key with OSCOAP directly (OSCOAP)

If OSCOAP 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:

.ti 6
o  a symmetric key (pop-key)
.ti 6
o  the sender identifier
.ti 6
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].

.ti 6
o  an AEAD algorithm
.ti 6
o  a KDF algorithm
.ti 6
o  a salt

The pop-key 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 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 OSCOAP context as described in section 3.1. of [I-D.ietf-core-object-security].  These MUST be included in the COSE_Key as header parameters, as defined in table 1.  As suggested in section 3.3 of [I-D.ietf-core-object-security], it is RECOMMENDED that the AS use pseudo-random 64-bit long IDs, so that the probability of collisions is negligible.


Note that C should receive the client id as 'sid' and the RS id as 'rid', while the RS should receive the RS id as 'sid' and the client id as 'rid'.
 
.nf
+---------+-------+----------------+------------+-------------------+
| name    | label | CBOR type      | registry   | description       |
+---------+-------+----------------+------------+-------------------+
| sid     | TBD   | bstr           |            | Identifies the    |
|         |       |                |            | sender in an      |
|         |       |                |            | OSCOAP context    |
|         |       |                |            | using this key    |
|         |       |                |            |                   |
| rid     | TBD   | bstr           |            | Identifies the    |
|         |       |                |            | recipient in an   |
|         |       |                |            | OSCOAP context    |
|         |       |                |            | using this key    |
|         |       |                |            |                   |
| kdf     | TBD   | bstr           |            | Identifies the    |
|         |       |                |            | KDF algorithm in  |
|         |       |                |            | an OSCOAP context |
|         |       |                |            | using this key    |
|         |       |                |            |                   |
| slt     | TBD   | bstr           |            | Identifies the    |
|         |       |                |            | master salt in    |
|         |       |                |            | an OSCOAP context |
|         |       |                |            | using this key    |
+---------+-------+----------------+------------+-------------------+
        Table 1: Additional common header parameters for COSE_Key 
.fi

Figure 1 shows an example of such an AS response, in CBOR diagnostic notation without the tag and value abbreviations.

.nf
    Header: Created (Code=2.01)
      Content-Type: "application/cose+cbor"
      Payload:
      {
        "access_token" : b64'SlAV32hkKG ...
         (remainder of access token omitted for brevity)',
        "profile" : "coap_oscoap",
        "expires_in" : "3600",
        "cnf" : {
          "COSE_Key" : {
            "kty" : "Symmetric",
            "alg" : "AES-CCM-16-64-128",
            "sid" : b64'qA',
            "rid" : b64'Qg',
            "k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
          }
        }
      }

      Figure 1: Example AS response with OSCOAP parameters.
.fi

Figure 2 shows an example CWT, containing the necessary OSCOAP parameters in the 'cnf' claim, in CBOR diagnostic notation without
tag and value abbreviations.


.nf
    {
      "aud" : "tempSensorInLivingRoom",
      "iat" : "1360189224",
      "exp" : "1360289224",
      "scope" :  "temperature_g firmware_p",
      "cnf" : {
        "COSE_Key" : {
          "kty" : "Symmetric",
          "alg" : "AES-CCM-16-64-128",
          "sid" : b64'Qg',
          "rid" : b64'qA',
          "k" : b64'+a+Dg2jjU+eIiOFCa9lObw' 
      }
    }

       Figure 2: Example CWT with OSCOAP parameters.
.fi

.ti 0
2.2.1 Using the pop-key with EDHOC (EDHOC+OSCOAP)

If EDHOC is used together with OSCOAP, 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:

.ti 6
o  a symmetric or asymmetric key (associated to the RS) (pop-key)
.ti 6
o  if the pop-key is symmetric, a key identifier;

How these parameters are communicated depends on the type of key (asymmetric or symmetric).

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].  Note that the key, sent by the AS in response to the access token request, is associated to the RS.

Figure 3 shows an example of such a request in CBOR diagnostic notation without tag and value abbreviations.

.nf
   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" : {
         "kty" : "EC",
         "crv" : "P-256",
         "x" : b64'usWxHK2PmfnHKwXPS54m0kTcGJ90UiglWiGahtagnv8',
         "y" : b64'IBOL+C3BttVivg+lSreASjpkttcsz+1rb7btKLv8EX4'
       }
     }
   }

  Figure 3: Example access token request with asymmetric pop key.
.fi


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 4 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.

.nf
    Header: Created (Code=2.01)
      Content-Type: "application/cose+cbor"
      Payload:
      {
        "access_token" : b64'SlAV32hkKG ...
         (remainder of access token omitted for brevity)',
        "profile" : "coap_oscoap",
        "expires_in" : "3600",
        "cnf" : {
          "COSE_Key" : {
            "kty" : "Symmetric",
            "kid" : b64'5tOS+h42dkw',
            "k" : b64'+a+Dg2jjU+eIiOFCa9lObw'
          }
        }
      }

   Figure 4: Example AS response with EDHOC+OSCOAP parameters.
.fi

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 5 shows an example CWT containing the necessary EDHOC+OSCOAP parameters in the 'cnf' claim, in CBOR diagnostic notation without
tag and value abbreviations.

.nf
    {
      "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 5: Example CWT with EDHOC+OSCOAP parameters.
.fi

All other parameters defining OSCOAP security context are derived from EDHOC message exchange, including the master secret (see Appendix C.2 of [I-D.selander-ace-cose-ecdhe]).

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, with the following additions and modifications.

The first CoAP message is sent to the RS using the /authz-info endpoint as specified in section 5.7.1 of the ACE framework. This message MUST carry message_1 of the EDHOC protocol (section 4.2. if asymmetric keys are used or 5.2. if symmetric keys are used of [I-D.selander-ace-cose-ecdhe]) in the CoAP payload, and the access token MUST be added to the message_1 APP_1 as an element in a serialized CBOR map, with the label 'access_token' (Figure 11 of [I-D.ietf-ace-oauth-authz]).  An example can be seen in the first message (POST) of Figure 1.

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], else it discontinues EDHOC and responds with the error code as specified in [I-D.ietf-ace-oauth-authz].

.in 3
When the RS receives an OSCOAP message including a field with label 'edhoc_m3' in the unprotected Headers of the COSE object, it SHALL follow the process described in Appendix C of [I-D.selander-ace-cose-ecdhe].  If the OSCOAP message was valid, the RS SHALL also verify that the client is authorized to perform the requested action on the requested resource using the previously received access token. 

.ti 6
o  In case the EDHOC verification fails, the RS MUST return an error response to the client with code 4.01 (Unauthorized).

.ti 6
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).

.ti 6
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).

.in 3
If all verifications above succeeds, further communication between client and RS is protected with OSCOAP, including the RS response to the OSCOAP request.

In the case of EDHOC being used with symmetric pop-keys, the protocol in section 5 of [I-D.selander-ace-cose-ecdhe] MUST be used.  If the pop-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.

Note that if the OSCOAP profile is used, the /authz-info endpoint at the Resource Server MUST be prepared to process and generate the protocol messages of the EDHOC protocol as specified above.  Hence the use of EDHOC does not add any additional roundtrips to the ACE message exchange.

  Figure 6 illustrates the message exchanges for using EDHOC on the /authz-info endpoint (step C in figure 1 of [I-D.ietf-ace-oauth-authz]).


.nf     
                     Resource
            Client    Server
            |          |
            |          |
            +--------->| Header: POST (Code=0.02)
            | POST     | Uri-Path:"authz-info"
            |          | Content-Type: application/cbor
            |          | Payload: EDHOC message_1 + access token
            |          |
            |<---------+ Header: 2.04 Changed
            |          | Content-Type: application/cose+cbor
            | 2.05     | Payload: EDHOC message_2
            |          |   
            |          |
            +--------->| CoAP request +
            |  OSCOAP  | Object-Security option
            | request  | COSE_Encrypt0:
            |          |  unprotected Header: EDHOC message_3
            |          |
            |<---------+ CoAP response +
            |  OSCOAP  | Object-Security option
            | response | 
            |          |  

   Figure 6: Key establishment with EDHOC via the authz-info endpoint
.fi

Figure 7 shows an example of message_1 with an access token embedded in the unprotected header.
.bp

.nf   
     [
       1,                            # message type
       h'05c2dc'                     # session identifier
       h'5598a57b47db7f2c',          # random nonce
       h'a120a50102024478f679012001215
         82098f50a4ff6c05861c8860d13a6
         38ea56c3f5ad7590bbfbf054e1c7b
         4d91d628022f5',             # COSE_Key
       [1]                           # NIST P-256
       [ -27 ],                      # ECDH-SS + HKDF-256
       [ 12 ],                       # AES-CCM-64-64-128
       [ -7 ],                       # ES256
       [ -7 ],                       # ES256
       h'a16c6163636573735f746f6b656e # APP_3: access token
         ...
     ] 
      
Figure 7: diagnostic notation of EDHOC message_1 with an access token
.fi

.ti 0
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 endpoint.  This section specifies how to use OSCOAP between Client and AS together with CoAP.  The use of OSCOAP 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 credentials (e.g. raw public keys).  How these credentials are established is out of scope for this profile.  Furthermore the client and the AS communicate using CoAP through the token endpoint as specified in section 5.5 of [I-D.ietf-ace-oauth-authz].  At first point of contact, prior to making the token request and response, the client and the AS MAY perform an EDHOC exchange with the pre-established credentials to create forward secret keying material for use with OSCOAP.  Subsequent requests and the responses MUST be protected with OSCOAP.


.ti 0
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 endpoint.  This section specifies how to use OSCOAP between RS and AS together with CoAP.  The use of OSCOAP 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 credentials (e.g. symmetric keys).  How these credentials are established is out of scope for this profile.  Furthermore the RS and the AS communicate using CoAP through the introspection endpoint as specified in section 5.6 of [I-D.ietf-ace-oauth-authz].  At first point of contact, prior to making the introspection request and response, the RS and the AS MAY perform an EDHOC exchange with the pre-established credentials to create forward secret keying material for use with OSCOAP.  Subsequent requests and the responses MUST be protected with OSCOAP.


.ti 0
5. Security Considerations

TBD.


.ti 0
6. Privacy Considerations

TBD.


.ti 0
7.  IANA Considerations 

TBD. 'coap_oscoap' as profile id. Header parameters 'sid', 'rid', 'kdf' and 'slt' for COSE_Key.


.ti 0
8.  Acknowledgments

The author wishes to thank Goeran Selander and Marco Tiloca for the input on this memo.  The error responses specified in section 2.2. were originally specified by
Gerdes et al. in [I-D.gerdes-ace-dcaf-authorize].


.ti 0
9.  References

.ti 0 
9.1  Normative References

.in 14
.ti 3
[I-D.ietf-core-object-security]
.br
Selander, G., Mattsson, J., Palombini, F., and L. Seitz, "Object Security of CoAP (OSCOAP)", draft-ietf-core-object-security-02 (work in progress), March 2017.

.ti 3
[I-D.selander-ace-cose-ecdhe]
.br
Selander, G., Mattsson, J., and F. Palombini, "Ephemeral Diffie-Hellman Over COSE (EDHOC)", draft-selander-ace-cose-ecdhe-06 (work in progress), April 2017.

.ti 3
[I-D.ietf-cose-msg]
.br
Schaad, J., "CBOR Object Signing and Encryption (COSE)", draft-ietf-cose-msg-24 (work in progress), November 2016.

.ti 3
[I-D.ietf-ace-oauth-authz]
.br
Seitz, L., Selander, G., Wahlstroem, E., Erdtmann, S., and H. Tschofenig. "Authentication and Authorization for Constrained Environments (ACE)", draft-ietf-ace-oauth-authz-06 (work in progress), March 2017.

.ti 3
[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-04 (work in progress), April 2017.

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.ti 3
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9.2  Informative References
.in 14

.ti 3
[I-D.ietf-ace-actors]
.br
Gerdes, S., Seitz, L., Selander, G., and C. Bormann (ed). "An Architecture for Authorization in Constrained Environments", draft-ietf-ace-actors-05 (work in progress), March 2017. 

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[I-D.gerdes-ace-dcaf-authorize]
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Gerdes, S., Bergmann, O., Bormann C. "Delegated CoAP Authentication and Authorization Framework (DCAF)", draft-gerdes-ace-dcaf-authorize-04 (work in progress), October 2015.

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Author's Address
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Ludwig Seitz
RISE SICS AB
Scheelevagen 17
22370 Lund
SWEDEN
EMail: ludwig.seitz@ri.se

Martin Gunnarsson
RISE SICS AB
Scheelevagen 17
22370 Lund
SWEDEN
EMail: martin.gunnarsson@ri.se

Francesca Palombini
Ericsson AB
Farogatan 6
SE-16480 Stockholm
SWEDEN
EMail: francesca.palombini@ericsson.com

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