Import content from draft-lenders-core-dtls-svcb

draft-ietf-core-coap-dtls-alpn.md

@@ -1,65 +1,123 @@
 ---
-v: 3
+title: "ALPN ID Specification for CoAP over DTLS "
+abbrev: "CoRE ALPN"
+category: std
 
-title: ALPN ID Specification for CoAP over DTLS
-abbrev: CoRE ALPN
 docname: draft-ietf-core-coap-dtls-alpn-latest
-
-wg: CoRE Working Group
-kw: Internet-Draft
-cat: std
-submissiontype: IETF
-
-coding: utf-8
+submissiontype: IETF  # also: "independent", "editorial", "IAB", or "IRTF"
+number:
+date:
+consensus: true
+v: 3
+area: "Web and Internet Transport"
+workgroup: "Constrained RESTful Environments"
+keyword:
+ - CoRE
+ - CoAP
+ - SVCB
+ - DTLS
+ - ALPN
+venue:
+    group: "Constrained RESTful Environments"
+    type: "Working Group"
+    mail: "[email protected]"
+    arch: "https://mailarchive.ietf.org/arch/browse/core/"
+    github: "anr-bmbf-pivot/draft-ietf-core-coap-dtls-alpn"
+    latest: "https://anr-bmbf-pivot.github.io/draft-ietf-core-coap-dtls-alpn/draft-ietf-core-coap-dtls-alpn.html"
 
 author:
- -
-    ins: X. Y.
-    name: X Y
-    organization: TBD
-    email: TBD
+ -  fullname: Martine Sophie Lenders
+    org: TUD Dresden University of Technology
+    abbrev: TU Dresden
+    street: Helmholtzstr. 10
+    city: Dresden
+    code: D-01069
+    country: Germany
+    email: [email protected]
+ -  name: Christian Amsüss
+    email: [email protected]
+ -  fullname: Thomas C. Schmidt
+    organization: HAW Hamburg
+    street: Berliner Tor 7
+    city: Hamburg
+    code: D-20099
+    country: Germany
+    email: [email protected]
+ -  name: Matthias Wählisch
+    org: TUD Dresden University of Technology & Barkhausen Institut
+    abbrev: TU Dresden & Barkhausen Institut
+    street: Helmholtzstr. 10
+    city: Dresden
+    code: D-01069
+    country: Germany
+    email: [email protected]
 
 normative:
-  RFC2119:
-  RFC8174:
+  RFC7252: coap
+  RFC7301: alpn
+  RFC9460: svcb
 
 informative:
-
-
-entity:
-  SELF: "[RFC-XXXX]"
-
+  RFC8323: coap-tcp
+  I-D.ietf-core-dns-over-coap: doc
+  RFC4944: 6lo
 
 --- abstract
 
-TODO Abstract
+This document specifies an Application-Layer Protocol Negotiation (ALPN) ID for
+transport-layer-secured CoAP services.
 
 --- middle
 
 # Introduction
 
-TODO Introduction
+Application-Layer Protocol Negotiation (ALPN) enable communicating parties to agree on an application-layer protocol during a Transport Layer Security (TLS) handshake using an ALPN ID.
+This ALPN ID can be discovered for services as part of Service Bindings (SVCB) via the DNS, using SVCB resource records with the "alpn" Service Parameter Keys.
+As an example, this information can be obtained as part of the discovery of DNS over CoAP (DoC) servers (see {{-doc}}) that deploy TLS or DTLS to secure their messages.
+This document specifies an ALPN ID for CoAP services that are secured by transport security using DTLS.
+An ALPN ID for CoAP service secured by TLS has already been specified in {{-coap-tcp}}.
+
+# Application-Layer Protocol Negotiation (ALPN) IDs
 
-## Terminology ## {#terminology}
+For CoAP over TLS an ALPN ID was defined as "coaps" in {{-coap-tcp}}.
+As it is not advisable to re-use the same ALPN ID for a different transport layer, an ALPN for
+CoAP over DTLS is registered in {{iana}}.
 
-{::boilerplate bcp14-tagged}
+ALPN ID values have variable length.
+Here, a short value ("co") is allocated for CoAP over DTLS, as this can avoid fragmentation of Client Hello and Server Hello messages in constrained networks with link-layer fragmentation, such as 6LoWPAN {{-6lo}}.
 
-TODO terminology.
+To discover CoAP services that secure their messages with TLS or DTLS, ALPN IDs "coaps" and "co" can be used respectively in
+the same manner as for any other service secured with transport layer security, as
+described in {{-svcb}}.
+Other authentication mechanisms are currently out of scope.
 
 # Security Considerations
 
-TODO Security
+Any security considerations on ALPN (see {{-alpn}}) and SVCB resource records (see {{-svcb}}), also
+apply to this document.
+
+# IANA Considerations {#iana}
 
+## TLS ALPN for CoAP
 
-# IANA Considerations
+The following entry has been added to the "TLS Application-Layer Protocol Negotiation (ALPN) Protocol IDs" registry, which is part of the "Transport Layer Security (TLS) Extensions" group.
 
-This document has no IANA actions.
+* Protocol: CoAP (over DTLS)
+* Identification sequence: 0x63 0x6f ("co")
+* Reference: {{-coap}} and \[this document\]
 
+Note that {{-coap}} does not define the use of the ALPN TLS extension during the DTLS connection handshake.
+This document does not change this behavior, and thus does not establish any rules like those in {{Section 8.2 of -coap-tcp}}.
 
 
 --- back
 
+# Change Log
+
+
 # Acknowledgments
 {:unnumbered}
 
-TODO acknowledge.
+We like to thank Rich Salz for the expert review on the "co" ALPN ID allocation.
+We also like to thank Mohamed Boucadair and Ben Schwartz for their early review before WG adoption
+of this draft.