ACE Working Group M. Jones
Internet-Draft Microsoft
Intended status: Informational E. Wahlström
Expires: July 17, 2017
S. Erdtman
Spotify AB
H. Tschofenig
ARM Ltd.
January 13, 2017

CBOR Web Token (CWT)
draft-ietf-ace-cbor-web-token-02

Abstract

CBOR Web Token (CWT) is a compact means of representing claims to be transferred between two parties. CWT is a profile of the JSON Web Token (JWT) that is optimized for constrained devices. The claims in a CWT are encoded in the Concise Binary Object Representation (CBOR) and CBOR Object Signing and Encryption (COSE) is used for added application layer security protection. A claim is a piece of information asserted about a subject and is represented as a name/value pair consisting of a claim name and a claim value.

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-Drafts is at http://datatracker.ietf.org/drafts/current/.

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This Internet-Draft will expire on July 17, 2017.

Copyright Notice

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Table of Contents

1. Introduction

The JSON Web Token (JWT) [RFC7519] is a standardized security token format that has found use in OAuth 2.0 and OpenID Connect deployments, among other applications. JWT uses JSON Web Signatures (JWS) [RFC7515] and JSON Web Encryption (JWE) [RFC7516] to secure the contents of the JWT, which is a set of claims represented in JSON [RFC7519]. The use of JSON for encoding information is popular for Web and native applications, but it is considered inefficient for some Internet of Things (IoT) systems that use low power radio technologies.

In this document an alternative encoding of claims is defined. Instead of using JSON, as provided by JWTs, this specification uses CBOR [RFC7049] and calls this new structure "CBOR Web Token (CWT)", which is a compact means of representing secured claims to be transferred between two parties. CWT is closely related to JWT. It references the JWT claims and both its name and pronunciation are derived from JWT. To protect the claims contained in CWTs, the CBOR Object Signing and Encryption (COSE) [I-D.ietf-cose-msg] specification is used.

The suggested pronunciation of CWT is the same as the English word "cot".

2. Terminology

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 "Key words for use in RFCs to Indicate Requirement Levels" [RFC2119].

This document reuses terminology from JWT [RFC7519] and COSE [I-D.ietf-cose-msg].

Type3StringOrURI:

The "Type3StringOrURI" term has the same meaning, syntax, and processing rules as the "StringOrUri" term defined in Section 2 of JWT [RFC7519], except that Type3StringOrURI uses CBOR major type 3 instead of a JSON string value.
Type6NumericDate:

The "Type6NumericDate" term has the same meaning, syntax, and processing rules as the "NumericDate" term defined in Section 2 of JWT [RFC7519], except that Type6NumericDate uses CBOR major type 6, with tag value 1, instead of a numeric JSON value.
CBOR encoded claim key:

The key used to identify a claim value.
CWT Claims Set

A CBOR map that contains the claims conveyed by the CWT.

3. Claims

The set of claims that a CWT must contain to be considered valid is context dependent and is outside the scope of this specification. Specific applications of CWTs will require implementations to understand and process some claims in particular ways. However, in the absence of such requirements, all claims that are not understood by implementations MUST be ignored.

To keep CWTs as small as possible, the CBOR encoded claim keys are represented using CBOR major type 0. Section 4 summarizes all keys used to identify the claims defined in this document.

3.1. Claim Names

None of the claims defined below are intended to be mandatory to use or implement. They rather provide a starting point for a set of useful, interoperable claims. Applications using CWTs should define which specific claims they use and when they are required or optional.

3.1.1. iss (Issuer) Claim

The iss (issuer) claim has the same meaning, syntax, and processing rules as the iss claim defined in Section 4.1.1 of JWT [RFC7519], except that the format MUST be a Type3StringOrURI. The CBOR encoded claim key 1 MUST be used to identify this claim.

3.1.2. sub (Subject) Claim

The sub (subject) claim has the same meaning, syntax, and processing rules as the sub claim defined in Section 4.1.2 of JWT [RFC7519], except that the format MUST be a Type3StringOrURI. The CBOR encoded claim key 2 MUST be used to identify this claim.

3.1.3. aud (Audience) Claim

The aud (audience) claim has the same meaning, syntax, and processing rules as the aud claim defined in Section 4.1.3 of JWT [RFC7519], except that the format MUST be a Type3StringOrURI. The CBOR encoded claim key 3 MUST be used to identify this claim.

3.1.4. exp (Expiration Time) Claim

The exp (expiration time) claim has the same meaning, syntax, and processing rules as the exp claim defined in Section 4.1.4 of JWT [RFC7519], except that the format MUST be a Type6NumericDate. The CBOR encoded claim key 4 MUST be used to identify this claim.

3.1.5. nbf (Not Before) Claim

The nbf (not before) claim has the same meaning, syntax, and processing rules as the nbf claim defined in Section 4.1.5 of JWT [RFC7519], except that the format MUST be a Type6NumericDate. The CBOR encoded claim key 5 MUST be used to identify this claim.

3.1.6. iat (Issued At) Claim

The iat (issued at) claim has the same meaning, syntax, and processing rules as the iat claim defined in Section 4.1.6 of JWT [RFC7519], except that the format MUST be a Type6NumericDate. The CBOR encoded claim key 6 MUST be used to identify this claim.

3.1.7. cti (CWT ID) Claim

The cti (CWT ID) claim has the same meaning, syntax, and processing rules as the jti claim defined in Section 4.1.7 of JWT [RFC7519], except that the format MUST be of major type 2, binary string. The CBOR encoded claim key 7 MUST be used to identify this claim.

4. Summary of the values, CBOR major types and encoded claim keys

/---------+------------------------+--------------------------\
| Claim   | CBOR encoded claim key | CBOR major type of value |
|---------+------------------------+--------------------------|
| iss     | 1                      | 3                        |
| sub     | 2                      | 3                        |
| aud     | 3                      | 3                        |
| exp     | 4                      | 6 tag value 1            |
| nbf     | 5                      | 6 tag value 1            |
| iat     | 6                      | 6 tag value 1            |
| cti     | 7                      | 2                        |
\---------+------------------------+--------------------------/

Figure 1: Summary of the values, CBOR major types and encoded claim keys.

5. Creating and Validating CWTs

5.1. Creating a CWT

To create a CWT, the following steps are performed. The order of the steps is not significant in cases where there are no dependencies between the inputs and outputs of the steps.

  1. Create a CWT Claims Set containing the desired claims.
  2. Let the Message be the binary representation of the CWT Claims Set.
  3. Create a COSE Header containing the desired set of Header Parameters. The COSE Header MUST be valid according to the [I-D.ietf-cose-msg] specification.
  4. Depending upon whether the CWT is signed, MACed or encrypted, there are three cases:
    • If the CWT is signed, create a COSE_Sign/COSE_Sign1 object using the Message as the COSE_Sign/COSE_Sign1 Payload; all steps specified in [I-D.ietf-cose-msg] for creating a COSE_Sign/COSE_Sign1 object MUST be followed.
    • Else, if the CWT is MACed, create a COSE_Mac/COSE_Mac0 object using the Message as the COSE_Mac/COSE_Mac0 Payload; all steps specified in [I-D.ietf-cose-msg] for creating a COSE_Mac/COSE_Mac0 object MUST be followed.
    • Else, if the CWT is a COSE_Encrypt/COSE_Encrypt0 object, create a COSE_Encrypt/COSE_Encrypt0 using the Message as the plaintext for the COSE_Encrypt/COSE_Encrypt0 object; all steps specified in [I-D.ietf-cose-msg] for creating a COSE_Encrypt/COSE_Encrypt0 object MUST be followed.

  5. If a nested signing, MACing or encryption operation will be performed, let the Message be the COSE_Sign/COSE_Sign1, COSE_Mac/COSE_Mac0 or COSE_Encrypt/COSE_Encrypt0, and return to Step 3, using a "content type" header value corresponding to the media type "application/cwt" in the new COSE Header created in that step.
    Note: If integrity (signing/MACing) and confidentiality (encryption) protection are needed, it is recommended to use an authenticated encryption algorithm to save space and processing.

5.2. Validating a CWT

When validating a CWT, the following steps are performed. The order of the steps is not significant in cases where there are no dependencies between the inputs and outputs of the steps. If any of the listed steps fail, then the CWT MUST be rejected -- that is, treated by the application as an invalid input.

  1. Verify that the CWT is a valid CBOR object.
  2. Verify that the resulting COSE Header includes only parameters and values whose syntax and semantics are both understood and supported or that are specified as being ignored when not understood.
  3. Use the CBOR tag to determine the type of the CWT, COSE_Sign/COSE_Sign1, COSE_Mac/COSE_Mac0, or COSE_Encrypt/COSE_Encrypt0.
  4. Depending upon whether the CWT is a COSE_Sign/COSE_Sign1, COSE_Mac/COSE_Mac0 or COSE_Encrypt/COSE_Encrypt0, there are three cases:
    • If the CWT is a COSE_Sign/COSE_Sign1, follow the steps specified in [I-D.ietf-cose-msg] Section 4 (Signing Objects) for validating a COSE_Sign/COSE_Sign1 object. Let the Message be the COSE_Sign/COSE_Sign1 payload.
    • Else, if the CWT is a COSE_Mac/COSE_Mac0, follow the steps specified in [I-D.ietf-cose-msg] Section 6 (MAC Objects) for validating a COSE_Mac/COSE_Mac0 object. Let the Message be the COSE_Mac/COSE_Mac0 payload.
    • Else, if the CWT is a COSE_Encrypt/COSE_Encrypt0 object, follow the steps specified in [I-D.ietf-cose-msg] Section 5 (Encryption Objects) for validating a COSE_Encrypt/COSE_Encrypt0 object. Let the Message be the resulting plaintext.

  5. If the COSE Header contains a "content type" header value corresponding to the media type "application/cwt", then the Message is a CWT that was the subject of nested signing or encryption operations. In this case, return to Step 1, using the Message as the CWT.
  6. Verify that the Message is a valid CBOR object; let the CWT Claims Set be this CBOR object.

6. Security Considerations

The security of the CWT is dependent on the protection offered by COSE. Without protecting the claims contained in a CWT an adversary is able to modify, add or remove claims. Since the claims conveyed in a CWT are used to make authorization decisions it is not only important to protect the CWT in transit but also to ensure that the recipient is able to authenticate the party that collected the claims and created the CWT. Without trust of the recipient in the party that created the CWT no sensible authorization decision can be made. Furthermore, the creator of the CWT needs to carefully evaluate each claim value prior to including it in the CWT so that the recipient can be assured about the correctness of the provided information.

7. IANA Considerations

7.1. CBOR Web Token (CWT) Claims Registry

This section establishes the IANA "CBOR Web Token (CWT) Claims" registry.

Values are registered on a Specification Required [RFC5226] basis, on the advice of one or more Designated Experts. However, to allow for the allocation of values prior to publication, the Designated Experts may approve registration once they are satisfied that such a specification will be published.

Criteria that should be applied by the Designated Experts includes determining whether the proposed registration duplicates existing functionality, whether it is likely to be of general applicability or whether it is useful only for a single application, and whether the registration description is clear.

7.1.1. Registration Template

Claim Name:

The human-readable name requested (e.g., "iss").
Claim Description:

Brief description of the claim (e.g., "Issuer").
JWT Claim Name:

Claim Name of the equivalent JWT claim as registered in [IANA.JWT.Claims]. CWT claims should normally have a corresponding JWT claim. If a corresponding JWT claim would not make sense, the Designated Experts can choose to accept registrations for which the JWT Claim Name is listed as "N/A".
CBOR Key Value:

Key value for the claim. The key value MUST be an integer in the range of 1 to 65536.
CBOR Major Type:

CBOR major type and optional tag for the claim.
Change Controller:

For Standards Track RFCs, list the "IESG". For others, give the name of the responsible party. Other details (e.g., postal address, email address, home page URI) may also be included.
Specification Document(s):

Reference to the document or documents that specify the parameter, preferably including URIs that can be used to retrieve copies of the documents. An indication of the relevant sections may also be included but is not required.

7.1.2. Initial Registry Contents

7.2. Media Type Registration

This section registers the application/cwt media type [RFC2046] in the "Media Types" registry [IANA.MediaTypes] in the manner described in RFC 6838 [RFC6838], which can be used to indicate that the content is a CWT.

7.2.1. Registry Contents

7.3. CoAP Content-Formats Registration

This section registers the CoAP Content-Format ID for the "application/cwt" media type in the "CoAP Content-Formats" registry [IANA.CoAP.Content-Formats] established by [RFC7252].

7.3.1. Registry Contents

8. References

8.1. Normative References

[I-D.ietf-cose-msg] Schaad, J., "CBOR Object Signing and Encryption (COSE)", Internet-Draft draft-ietf-cose-msg-24, November 2016.
[IANA.CoAP.Content-Formats] IANA, "CoAP Content-Formats"
[IANA.JWT.Claims] IANA, "JSON Web Token Claims"
[IANA.MediaTypes] IANA, "Media Types"
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, DOI 10.17487/RFC2046, November 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, DOI 10.17487/RFC5226, May 2008.
[RFC6838] Freed, N., Klensin, J. and T. Hansen, "Media Type Specifications and Registration Procedures", BCP 13, RFC 6838, DOI 10.17487/RFC6838, January 2013.
[RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049, October 2013.
[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March 2014.
[RFC7252] Shelby, Z., Hartke, K. and C. Bormann, "The Constrained Application Protocol (CoAP)", RFC 7252, DOI 10.17487/RFC7252, June 2014.
[RFC7515] Jones, M., Bradley, J. and N. Sakimura, "JSON Web Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May 2015.
[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)", RFC 7516, DOI 10.17487/RFC7516, May 2015.
[RFC7519] Jones, M., Bradley, J. and N. Sakimura, "JSON Web Token (JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015.

8.2. Informative References

[I-D.seitz-ace-oauth-authz] Seitz, L., Selander, G., Wahlstroem, E., Erdtman, S. and H. Tschofenig, "Authorization for the Internet of Things using OAuth 2.0", Internet-Draft draft-seitz-ace-oauth-authz-00, October 2015.

Appendix A. Examples

Three examples of CWTs follow.

A.1. CWT with "aud" and symmetric key

A CWT used in the context of ACE requires at least the aud and a cks claim (defined elsewhere). This means that iss, alg, key_ops and others are pre-established and assumed. This would look like this non-normative JSON.


{
  "aud":"coap://light.example.com",
  "cks":
    [                       // COSE_Key is a CBOR map with an array of keys
      {
        "kty":4,            // symmetric key is indicated using kty 4
        "k": "loremipsum"   // the symmetric key
      }
    ]
}

            

Figure 2: "aud" claim and symmetric key in non-normative JSON

Using the CBOR encoded claim keys according to Section 4 and COSE [I-D.ietf-cose-msg] makes a CWT with aud and a symmetric key look like this in CBOR diagnostic notation:


{
  3: "coap://light.example.com",
  8:
  [
    {
      1: 4,
      -1: "loremipsum"
    }
  ]
}

            

Figure 3: CWT in CBOR diagnostic notation

Defined in CBOR.


a2                                      # map(2)
   03                                   # unsigned(3)
   78 18                                # text(24)
      636f61703a2f2f6c696768742e6578616d706c652e636f6d # "coap://light.example.com"
   08                                   # unsigned(8)
   81                                   # array(1)
      a2                                # map(2)
         01                             # unsigned(1)
         04                             # unsigned(4)
         20                             # negative(0)
         6a                             # text(10)
            6c6f72656d697073756d        # "loremipsum"

            

Figure 4: CWT with "aud" and symmetric key in CBOR

Size of the CWT with a symmetric key of 10 bytes is 45 bytes. This is then packaged signed and encrypted using COSE.

A.2. CWT with "aud" and EC key

Token with aud set to "coap://light.example.com" and an EC key with kid set to 11.


{
  "aud": "coap://light.example.com",
  "cks":
    [                       // COSE_Key is a CBOR map with an array of keys
      {
        "kty": "EC",
        "kid": "11",
        "crv": 1, // using P-384
        "x": h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',
        "y": h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e'
      }
    ]
}

            

Figure 5: "aud" claim and EC key in non-normative JSON

Using the CBOR encoded claim keys according to Section 4 and COSE [I-D.ietf-cose-msg] makes a CWT with aud and an EC key look like this in CBOR diagnostic notation:


{
  3: "coap://light.example.com",
  8:
  [
    {
      1: 2,
      2: "11",
      -1: 1,
      -2: h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',
      -3: h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e'
    }
  ]
}

            

Figure 6: CWT with EC key in CBOR diagnostic notation

Defined in CBOR.


a2                                      # map(2)
   03                                   # unsigned(3)
   78 18                                # text(24)
      636f61703a2f2f6c696768742e6578616d706c652e636f6d # "coap://light.example.com"
   08                                   # unsigned(8)
   81                                   # array(1)
      a5                                # map(5)
         01                             # unsigned(1)
         02                             # unsigned(2)
         02                             # unsigned(2)
         62                             # text(2)
            3131                        # "11"
         20                             # negative(0)
         01                             # unsigned(1)
         21                             # negative(1)
         58 20                          # bytes(32)
            bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff # "\xBA\xC5\xB1\x1C\xAD\x8F\x99\xF9\xC7+\x05\xCFK\x9E&\xD2D\xDC\x18\x9FtR(%Z!\x9A\x86\xD6\xA0\x9E\xFF"
         22                             # negative(2)
         58 20                          # bytes(32)
            20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e # "\x13\x8B\xF8-\xC1\xB6\xD5b\xBE\x0F\xA5J\xB7\x80J:d\xB6\xD7,\xCF\xEDko\xB6\xED(\xBB\xFC\x11~"

            

Figure 7: CWT with EC in CBOR

Size of the CWT with an EC key is 109 bytes. This is then packaged signed and encrypted using COSE.

A.3. Full CWT

CWT using all claims defined by this specification, plus extensions for AIF and an EC key.


{
   "iss": "coap://as.example.com",
   "aud": "coap://light.example.com",
   "sub": "erikw",
   "exp": 1444064944,
   "nbf": 1443944944,
   "iat": 1443944944,
   "cti": 2929,
   "cks":
     [                       // COSE_Key is a CBOR map with an array of keys
       {
         "kty": "EC",
         "kid": "11",
         "crv": 1, // using P-384
         "x": h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',
         "y": h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e'
       }
     ],
   "aif": [["/s/light", 1], ["/a/led", 5], ["/dtls", 2]]
 }

            

Figure 8: All claims, "aif" and EC key in non-normative JSON

Using the CBOR encoded claim keys according to Section 4 and COSE [I-D.ietf-cose-msg] makes a full CWT look like this in CBOR diagnostic notation:


{
  1: "coap://as.example.com",
  3: "coap://light.example.com",
  2: "erikw",
  4: 1(1444064944),
  5: 1(1443944944),
  6: 1(1443944944),
  7: 2929,
  8: [
    {
      1: 2,
      2: "11",
      -1: 1,
      -2: h'bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff',
      -3: h'20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e'
    }
    ],
  9: [["/s/light", 1], ["/a/led", 5], ["/dtls", 2]]
}

            

Figure 9: Full CWT with EC key in CBOR diagnostic notation

Defined in CBOR.


a9                                      # map(9)
   01                                   # unsigned(1)
   75                                   # text(21)
      636f61703a2f2f61732e6578616d706c652e636f6d # "coap://as.example.com"
   03                                   # unsigned(3)
   78 18                                # text(24)
      636f61703a2f2f6c696768742e6578616d706c652e636f6d # "coap://light.example.com"
   02                                   # unsigned(2)
   65                                   # text(5)
      6572696b77                        # "erikw"
   04                                   # unsigned(4)
   c1                                   # tag(1)
      1a 5612aeb0                       # unsigned(1444064944)
   05                                   # unsigned(5)
   c1                                   # tag(1)
      1a 5610d9f0                       # unsigned(1443944944)
   06                                   # unsigned(6)
   c1                                   # tag(1)
      1a 5610d9f0                       # unsigned(1443944944)
   07                                   # unsigned(7)
   19 0b71                              # unsigned(2929)
   08                                   # unsigned(8)
   81                                   # array(1)
      a5                                # map(5)
         01                             # unsigned(1)
         02                             # unsigned(2)
         02                             # unsigned(2)
         62                             # text(2)
            3131                        # "11"
         20                             # negative(0)
         01                             # unsigned(1)
         21                             # negative(1)
         58 20                          # bytes(32)
            bac5b11cad8f99f9c72b05cf4b9e26d244dc189f745228255a219a86d6a09eff # "\xBA\xC5\xB1\x1C\xAD\x8F\x99\xF9\xC7+\x05\xCFK\x9E&\xD2D\xDC\x18\x9FtR(%Z!\x9A\x86\xD6\xA0\x9E\xFF"
         22                             # negative(2)
         58 20                          # bytes(32)
            20138bf82dc1b6d562be0fa54ab7804a3a64b6d72ccfed6b6fb6ed28bbfc117e # "\x13\x8B\xF8-\xC1\xB6\xD5b\xBE\x0F\xA5J\xB7\x80J:d\xB6\xD7,\xCF\xEDko\xB6\xED(\xBB\xFC\x11~"
   09                                   # unsigned(9)
   83                                   # array(3)
      82                                # array(2)
         68                             # text(8)
            2f732f6c69676874            # "/s/light"
         01                             # unsigned(1)
      82                                # array(2)
         66                             # text(6)
            2f612f6c6564                # "/a/led"
         05                             # unsigned(5)
      82                                # array(2)
         65                             # text(5)
            2f64746c73                  # "/dtls"
         02                             # unsigned(2)

            

Figure 10: Full CWT with EC in CBOR

Size of the CWT with an EC key is 194 bytes. This is then packaged signed and encrypted using COSE.

Appendix B. Acknowledgements

This specification is based on JSON Web Token (JWT) [RFC7519], the authors of which also include Nat Sakimura and John Bradley. A straw man proposal of CWT was written in the draft "Authorization for the Internet of Things using OAuth 2.0" [I-D.seitz-ace-oauth-authz] with the help of Ludwig Seitz and Göran Selander.

Appendix C. Document History

[[ to be removed by the RFC Editor before publication as an RFC ]]

-02

  • Added IANA registration for the application/cwt media type.
  • Clarified the nested CWT language.
  • Corrected nits identified by Ludwig Seitz.

-01

  • Added IANA registration for CWT Claims.
  • Added IANA registration for the application/cwt CoAP content-format type.
  • Added Samuel Erdtman as an editor.
  • Changed Erik's e-mail address.

-00

  • Created the initial working group version based on draft-wahlstroem-ace-cbor-web-token-00.

Authors' Addresses

Michael B. Jones Microsoft EMail: mbj@microsoft.com URI: http://self-issued.info/
Erik Wahlström Sweden EMail: erik@wahlstromstekniska.se
Samuel Erdtman Spotify AB Birger Jarlsgatan 61, 4tr Stockholm, 113 56 Sweden Phone: +46702691499 EMail: erdtman@spotify.com
Hannes Tschofenig ARM Ltd. Hall in Tirol, 6060 Austria EMail: Hannes.Tschofenig@arm.com