| Internet-Draft | sdf-protocol-mapping | February 2026 |
| Mohan, et al. | Expires 28 August 2026 | [Page] |
This document defines protocol mapping extensions for the Semantic Definition Format (SDF) to enable mapping of protocol-agnostic SDF affordances to protocol-specific operations. The protocol mapping mechanism allows SDF models to specify how properties, actions, and events should be accessed using specific non-IP and IP protocols such as Bluetooth Low Energy, Zigbee or HTTP and CoAP. This document also describes a method to extend SCIM with an SDF model mapping.¶
This note is to be removed before publishing as an RFC.¶
Status information for this document may be found at https://datatracker.ietf.org/doc/draft-ietf-asdf-sdf-protocol-mapping/.¶
Discussion of this document takes place on the A Semantic Definition Format for Data and Interactions of Things Working Group mailing list (mailto:asdf@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/asdf/. Subscribe at https://www.ietf.org/mailman/listinfo/asdf/.¶
Source for this draft and an issue tracker can be found at https://github.com/ietf-wg-asdf/sdf-protocol-mapping.¶
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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 https://datatracker.ietf.org/drafts/current/.¶
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Copyright (c) 2026 IETF Trust and the persons identified as the document authors. All rights reserved.¶
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
The Semantic Definition Format (SDF) [RFC9880] provides a protocol-agnostic way to describe IoT devices and their capabilities through properties, actions, and events (collectively called affordances). When implementing the SDF model for a device on an actual implementation using specific communication protocols, there needs to be a mechanism to map the protocol-agnostic SDF definitions to protocol-specific operations, translating the model into a real-world implementation.¶
This document defines such a mechanism using the sdfProtocolMap keyword,
which allows SDF models to include protocol-specific mapping information
attached to the protocol-agnostic definitions. An sdfProtocolMap can be applied to
an sdfAffordance, be it an sdfProperty, sdfEvent or sdfAction. The mapping enables use cases
such as application gateways or multi-protocol gateways that translate between different IoT protocols,
automated generation of protocol-specific implementations from SDF models, and
interoperability across heterogeneous device ecosystems.¶
The protocol mapping mechanism is designed to be extensible: target protocols include non-IP protocols commonly used in IoT environments, such as [BLE53] and [Zigbee30], as well as IP-based protocols such as HTTP [RFC9110] or CoAP [RFC7252]. This document registers mappings for BLE and Zigbee; future specifications can define mappings for additional protocols.¶
SDF provides a way to describe a class of devices and SCIM describes a device instance. The SDF model extension in this document defines a SCIM extension that enables inclusion of the SDF model for the class of devices a device belongs to in the SCIM object for that device.¶
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 BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
This section defines the structure of an sdfProtocolMap.
Because each protocol has its own addressing model, a single SDF
affordance requires a distinct mapping per protocol. For example, BLE
addresses a property as a service characteristic, while Zigbee addresses
it as an attribute in a cluster of an endpoint.¶
A protocol mapping object is a JSON object identified by the sdfProtocolMap
keyword, nested inside an SDF affordance definition (sdfProperty, sdfAction,
or sdfEvent). Protocol-specific attributes are embedded within this object,
keyed by an IANA registered protocol name, e.g., "ble" or "zigbee".¶
The sdfProtocolMap keyword is introduced into SDF affordance definitions
through the extension points defined in the formal syntax of [RFC9880]
(Appendix A). For each affordance type, an sdfProtocolMap entry is added
via the corresponding CDDL group socket. The contents of the
sdfProtocolMap object are in turn extensible through a
protocol-mapping-specific group socket.¶
A protocol MAY choose to extend only the affordance types that are applicable to it. For example, the BLE protocol mapping defines extensions for properties and events but not for actions.¶
The $$SDF-EXTENSION-PROPERTY group socket in the propertyqualities
rule of [RFC9880] (Appendix A) is used to add protocol mapping to
sdfProperty definitions:¶
$$SDF-EXTENSION-PROPERTY //= (
sdfProtocolMap: {
* $$SDF-PROPERTY-PROTOCOL-MAP
}
)
property-protocol-map<name, props> = (
name => props /
{
read: props,
write: props
}
)
The property-protocol-map generic (Figure 2) captures the common
structure of property protocol mappings. The name parameter is the
registered protocol name and props is the protocol-specific map of
attributes. A protocol can provide either:¶
A single mapping that applies to both read and write operations, or¶
Separate read and write mappings when the protocol uses different
attributes for each direction.¶
To extend $$SDF-PROPERTY-PROTOCOL-MAP for a new protocol (e.g., "new-protocol"),
use the property-protocol-map generic with the protocol name and a map type
defining the protocol-specific attributes. The protocol name
("new-protocol") MUST be registered in the IANA registry defined in
Section 7.1.¶
For example:¶
$$SDF-PROPERTY-PROTOCOL-MAP //= (
property-protocol-map<"new-protocol", new-protocol-property>
)
new-protocol-property = {
attributeA: text,
attributeB: uint
}
The corresponding JSON in an SDF model looks like:¶
{
"sdfProperty": {
"temperature": {
"type": "number",
"unit": "Cel",
"sdfProtocolMap": {
"new-protocol": {
"attributeA": "temperature-service",
"attributeB": 1
}
}
}
}
}
When a property uses different protocol attributes for read and write operations, the mapping can be split:¶
{
"sdfProperty": {
"temperature": {
"type": "number",
"unit": "Cel",
"sdfProtocolMap": {
"new-protocol": {
"read": {
"attributeA": "temperature-read-service",
"attributeB": 1
},
"write": {
"attributeA": "temperature-write-service",
"attributeB": 2
}
}
}
}
}
}
The $$SDF-EXTENSION-ACTION group socket in the actionqualities
rule of [RFC9880] (Appendix A) is used to add protocol mapping to
sdfAction definitions:¶
$$SDF-EXTENSION-ACTION //= (
sdfProtocolMap: {
* $$SDF-ACTION-PROTOCOL-MAP
}
)
Actions use a simpler structure than properties, as they do not require
the read/write distinction. To extend $$SDF-ACTION-PROTOCOL-MAP for a
new protocol, add a group entry mapping the protocol name to the
protocol-specific attributes:¶
$$SDF-ACTION-PROTOCOL-MAP //= (
"new-protocol": new-protocol-action
)
new-protocol-action = {
commandID: uint
}
The corresponding JSON in an SDF model would look like:¶
{
"sdfAction": {
"reset": {
"sdfProtocolMap": {
"new-protocol": {
"commandID": 42
}
}
}
}
}
The $$SDF-EXTENSION-EVENT group socket in the eventqualities
rule of [RFC9880] (Appendix A) is used to add protocol mapping to
sdfEvent definitions:¶
$$SDF-EXTENSION-EVENT //= (
sdfProtocolMap: {
* $$SDF-EVENT-PROTOCOL-MAP
}
)
Events follow the same simple pattern as actions. To extend
$$SDF-EVENT-PROTOCOL-MAP for a new protocol:¶
$$SDF-EVENT-PROTOCOL-MAP //= (
"new-protocol": new-protocol-event
)
new-protocol-event = {
eventID: uint
}
The corresponding JSON in an SDF model looks like:¶
{
"sdfEvent": {
"alert": {
"sdfProtocolMap": {
"new-protocol": {
"eventID": 3
}
}
}
}
}
Protocol names used as keys in the sdfProtocolMap object (e.g., "ble",
"zigbee") MUST be registered in the IANA registry defined in
Section 7.1.¶
A new protocol mapping MUST be defined by a specification that includes:¶
A CDDL definition that extends at least one of the group sockets
defined in this document:
$$SDF-PROPERTY-PROTOCOL-MAP (Section 3.1.1),
$$SDF-ACTION-PROTOCOL-MAP (Section 3.1.2), or
$$SDF-EVENT-PROTOCOL-MAP (Section 3.1.3).
Property mappings SHOULD use the property-protocol-map generic
(Section 3.1.1) to ensure a consistent structure.¶
A description of the protocol-specific attributes introduced by the CDDL extension, including their semantics and how they relate to the underlying protocol operations.¶
This section defines the protocol mappings registered by this document.¶
The BLE protocol mapping allows SDF models to specify how properties and events should be accessed using Bluetooth Low Energy (BLE) protocol. The mapping includes details such as service IDs and characteristic IDs that are used to access the corresponding SDF affordances.¶
For SDF properties, the BLE protocol mapping structure is defined as follows:¶
$$SDF-PROPERTY-PROTOCOL-MAP //= (
property-protocol-map<"ble", ble-property>
)
ble-property = {
serviceID: text,
characteristicID: text
}
Where:¶
serviceID is the BLE service ID that corresponds to the SDF property.¶
characteristicID is the BLE characteristic ID that corresponds to the SDF property.¶
For example, a BLE protocol mapping for a temperature property:¶
{
"sdfProperty": {
"temperature": {
"sdfProtocolMap": {
"ble": {
"serviceID": "12345678-1234-5678-1234-56789abcdef4",
"characteristicID": "12345678-1234-5678-1234-56789abcdef5"
}
}
}
}
}
¶
For a temperature property that has different mappings for read and write operations, here is an example of the BLE protocol mapping:¶
{
"sdfProperty": {
"temperature": {
"sdfProtocolMap": {
"ble": {
"read": {
"serviceID": "12345678-1234-5678-1234-56789abcdef4",
"characteristicID": "12345678-1234-5678-1234-56789abcdef5"
},
"write": {
"serviceID": "12345678-1234-5678-1234-56789abcdef4",
"characteristicID": "12345678-1234-5678-1234-56789abcdef6"
}
}
}
}
}
}
¶
For SDF events, the BLE protocol mapping structure is similar to SDF properties, but it must include additional attributes such as the type of the event.¶
$$SDF-EVENT-PROTOCOL-MAP //= (
ble: ble-event-map
)
ble-event-map = {
type: "gatt" / "advertisements" / "connection_events",
? serviceID: text,
? characteristicID: text
}
Where:¶
type specifies the type of BLE event, such as "gatt" for GATT events,
"advertisements" for advertisement events, or "connection_events" for
connection-related events.¶
serviceID and characteristicID are optional attributes that are
specified if the type is "gatt".¶
For example, a BLE event mapping for a heart rate measurement event:¶
{
"sdfEvent": {
"heartRate": {
"sdfProtocolMap": {
"ble": {
"type": "gatt",
"serviceID": "12345678-1234-5678-1234-56789abcdef4",
"characteristicID": "12345678-1234-5678-1234-56789abcdef5"
}
}
}
}
}
¶
Here is an example of an isPresent event using BLE advertisements:¶
{
"sdfEvent": {
"isPresent": {
"sdfProtocolMap": {
"ble": {
"type": "advertisements"
}
}
}
}
}
¶
The Zigbee protocol mapping allows SDF models to specify how properties, actions, and events should be accessed using the Zigbee protocol. The mapping includes details such as cluster IDs and attribute IDs that are used to access the corresponding SDF affordances.¶
SDF properties are mapped to Zigbee cluster attributes. The Zigbee property protocol mapping structure is defined as follows:¶
$$SDF-PROPERTY-PROTOCOL-MAP //= (
property-protocol-map<"zigbee", zigbee-property>
)
zigbee-property = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
attributeID: uint,
attributeType: uint
}
Where:¶
endpointID is the Zigbee endpoint ID that corresponds to the SDF property.¶
clusterID is the Zigbee cluster ID that corresponds to the SDF property.¶
attributeID is the Zigbee attribute ID that corresponds to the SDF property.¶
attributeType is the Zigbee data type of the attribute.¶
manufacturerCode is the Zigbee manufacturer code of the attribute (optional).¶
For example, a Zigbee protocol mapping for a temperature property:¶
{
"sdfProperty": {
"temperature": {
"sdfProtocolMap": {
"zigbee": {
"endpointID": 1,
"clusterID": 1026, // 0x0402
"attributeID": 0, // 0x0000
"attributeType": 41 // 0x29
}
}
}
}
}
¶
SDF events are mapped to Zigbee cluster attribute reporting. The Zigbee event protocol mapping structure is defined as follows:¶
$$SDF-EVENT-PROTOCOL-MAP //= (
zigbee: zigbee-event-map
)
zigbee-event-map = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
attributeID: uint,
attributeType: uint
}
For example, a Zigbee event mapping for a temperature change report:¶
{
"sdfEvent": {
"temperatureChange": {
"sdfProtocolMap": {
"zigbee": {
"endpointID": 1,
"clusterID": 1026, // 0x0402
"attributeID": 0, // 0x0000
"attributeType": 41 // 0x29
}
}
}
}
}
¶
SDF actions are mapped to Zigbee cluster commands. The Zigbee protocol mapping structure for actions is defined as follows:¶
$$SDF-ACTION-PROTOCOL-MAP //= (
zigbee: zigbee-action-map
)
zigbee-action-map = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
commandID: uint
}
Where:¶
endpointID is the Zigbee endpoint ID that corresponds to the SDF action.¶
clusterID is the Zigbee cluster ID that corresponds to the SDF action.¶
commandID is the Zigbee command ID that corresponds to the SDF action.¶
For example, a Zigbee protocol mapping to set a temperature:¶
{
"sdfAction": {
"setTemperature": {
"sdfProtocolMap": {
"zigbee": {
"endpointID": 1,
"clusterID": 1026, // 0x0402
"commandID": 0 // 0x0000
}
}
}
}
}
¶
While SDF provides a way to describe a device class and SCIM defines a device instance, a method is needed to associate a mapping between an instance of a device and its associated SDF models. To accomplish this, we define a SCIM extension that can be used in conjunction with [I-D.ietf-scim-device-model] in Figure 17. Implementation of this SCIM extension is OPTIONAL and independent of the protocol mapping functionality defined in the rest of this document. The SCIM schema attributes used here are described in Section 7 of [RFC7643].¶
=============== NOTE: '\' line wrapping per RFC 8792 ================
{
"id": "urn:ietf:params:scim:schemas:extension:sdf:2.0:Device",
"name": "SDFExtension",
"description": "Device extension schema for SDF.",
"attributes": [
{
"name": "sdf",
"type": "string",
"description": "SDF models supported by the device.",
"multiValued": true,
"required": true,
"caseExact": true,
"mutability": "readWrite",
"returned": "default",
"uniqueness": "none"
}
],
"meta": {
"resourceType": "Schema",
"location": "/v2/Schemas/urn:ietf:params:scim:schemas:extens\
ion:sdf:2.0:Device"
}
}
Here is an example SCIM device schema extension with SDF models:¶
{
"schemas": [
"urn:ietf:params:scim:schemas:core:2.0:Device",
"urn:ietf:params:scim:schemas:extension:sdf:2.0:Device"
],
"id": "e9e30dba-f08f-4109-8486-d5c6a3316111",
"displayName": "Heart Monitor",
"active": true,
"urn:ietf:params:scim:schemas:extension:sdf:2.0:Device": {
"sdf": [
"https://example.com/thermometer#/sdfThing/thermometer",
"https://example.com/heartrate#/sdfObject/healthsensor"
]
}
}
¶
An SDF model must be referenced with the sdf keyword inside the SCIM device schema as described in [I-D.ietf-scim-device-model].¶
The security considerations of [RFC9880] apply to this document as well.¶
Each protocol mapped using this mechanism has its own security model. The protocol mapping mechanism defined in this document does not provide additional security beyond what is offered by the underlying protocols. Implementations MUST ensure that appropriate protocol-level security mechanisms are employed when accessing affordances through the mapped protocol operations.¶
This section provides guidance to the Internet Assigned Numbers Authority (IANA) regarding registration of values related to this document, in accordance with [RFC8126].¶
IANA is requested to create a new registry called "SDF Protocol Mapping".¶
The registration policy for this registry is "Specification Required" as defined in Section 4.6 of [RFC8126].¶
The registry must contain the following attributes:¶
Protocol map name¶
Protocol name¶
Description¶
Reference of the specification describing the protocol mapping.¶
The specification requirements for a registration request are defined in Section 3.2.¶
The designated expert(s) SHOULD verify that the protocol map name is appropriate and not likely to cause confusion with existing entries.¶
The registrant of an existing entry may request updates to that entry, subject to the same expert review. They should verify that updates preserve backward compatibility with deployed implementations, or if breaking changes are necessary, consider whether a new registry entry is more appropriate.¶
The following protocol mappings are described in this document:¶
| Protocol map | Protocol Name | Description | Reference |
|---|---|---|---|
| ble | Bluetooth Low Energy (BLE) | Protocol mapping for BLE devices | This document |
| zigbee | Zigbee | Protocol mapping for Zigbee devices | This document |
IANA is requested to create the following extensions in the SCIM Server-Related Schema URIs registry as described in Section 5:¶
| URN | Description | Resource Type | Reference |
|---|---|---|---|
| urn:ietf:params:scim: schemas:extension: sdf:2.0:Device | SDF Extension | Device | This memo, Section 5 |
This appendix contains the combined CDDL definitions for the SDF protocol mappings.¶
<CODE BEGINS> file "sdf-protocol-map.cddl"
$$SDF-EXTENSION-PROPERTY //= (
sdfProtocolMap: {
* $$SDF-PROPERTY-PROTOCOL-MAP
}
)
property-protocol-map<name, props> = (
name => props /
{
read: props,
write: props
}
)
$$SDF-EXTENSION-ACTION //= (
sdfProtocolMap: {
* $$SDF-ACTION-PROTOCOL-MAP
}
)
$$SDF-EXTENSION-EVENT //= (
sdfProtocolMap: {
* $$SDF-EVENT-PROTOCOL-MAP
}
)
$$SDF-PROPERTY-PROTOCOL-MAP //= (
property-protocol-map<"ble", ble-property>
)
ble-property = {
serviceID: text,
characteristicID: text
}
$$SDF-EVENT-PROTOCOL-MAP //= (
ble: ble-event-map
)
ble-event-map = {
type: "gatt" / "advertisements" / "connection_events",
? serviceID: text,
? characteristicID: text
}
$$SDF-PROPERTY-PROTOCOL-MAP //= (
property-protocol-map<"zigbee", zigbee-property>
)
zigbee-property = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
attributeID: uint,
attributeType: uint
}
$$SDF-EVENT-PROTOCOL-MAP //= (
zigbee: zigbee-event-map
)
zigbee-event-map = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
attributeID: uint,
attributeType: uint
}
$$SDF-ACTION-PROTOCOL-MAP //= (
zigbee: zigbee-action-map
)
zigbee-action-map = {
endpointID: uint,
? manufacturerCode: uint,
clusterID: uint,
commandID: uint
}
<CODE ENDS>
¶
The following non-normative model is provided for convenience of the implementor.¶
<CODE BEGINS> file "ProtocolMap.yaml"
=============== NOTE: '\' line wrapping per RFC 8792 ================
openapi: 3.0.3
info:
title: SDF Protocol Mapping
description: |-
SDF Protocol Mapping. When adding a
new protocol mapping please add a reference to the protocol map
for all the schemas in this file.
version: 0.10.0
externalDocs:
description: SDF Protocol Mapping IETF draft
url: https://datatracker.ietf.org/doc/draft-ietf-asdf-sdf-protocol\
-mapping/
paths: {}
components:
schemas:
## Protocol Map for a property
ProtocolMap-Property:
type: object
properties:
sdfProtocolMap:
oneOf:
- $ref: './ProtocolMap-BLE.yaml#/components/schemas/Prot\
ocolMap-BLE-Propmap'
- $ref: './ProtocolMap-Zigbee.yaml#/components/schemas/P\
rotocolMap-Zigbee-Propmap'
## Protocol Map for an event
ProtocolMap-Event:
type: object
properties:
sdfProtocolMap:
oneOf:
- $ref: './ProtocolMap-BLE.yaml#/components/schemas/Prot\
ocolMap-BLE-Event'
- $ref: './ProtocolMap-Zigbee.yaml#/components/schemas/P\
rotocolMap-Zigbee-Event'
<CODE ENDS>
<CODE BEGINS> file "ProtocolMap-BLE.yaml"
=============== NOTE: '\' line wrapping per RFC 8792 ================
openapi: 3.0.3
info:
title: SDF Protocol Mapping for BLE
description: |-
SDF Protocol Mapping for BLE devices.
version: 0.10.0
externalDocs:
description: SDF Protocol Mapping IETF draft
url: https://datatracker.ietf.org/doc/draft-ietf-asdf-sdf-protocol\
-mapping/
paths: {}
components:
schemas:
## Protocol Mapping for BLE Property
ProtocolMap-BLE-Propmap:
required:
- ble
type: object
properties:
ble:
required:
- serviceID
- characteristicID
type: object
properties:
serviceID:
type: string
format: uuid
example: 00001809-0000-1000-8000-00805f9b34fb
characteristicID:
type: string
format: uuid
example: 00002a1c-0000-1000-8000-00805f9b34fb
## Defines different types of BLE events
ProtocolMap-BLE-Event:
required:
- ble
type: object
properties:
ble:
required:
- type
type: object
properties:
type:
type: string
example: gatt
enum:
- gatt
- connection_events
- advertisements
serviceID:
type: string
example: 00001809-0000-1000-8000-00805f9b34fb
characteristicID:
type: string
example: 00002a1c-0000-1000-8000-00805f9b34fb
<CODE ENDS>
<CODE BEGINS> file "ProtocolMap-Zigbee.yaml"
=============== NOTE: '\' line wrapping per RFC 8792 ================
openapi: 3.0.3
info:
title: SDF Protocol Mapping for Zigbee
description: |-
SDF Protocol Mapping for Zigbee devices.
version: 0.10.0
externalDocs:
description: SDF Protocol Mapping IETF draft
url: https://datatracker.ietf.org/doc/draft-ietf-asdf-sdf-protocol\
-mapping/
paths: {}
components:
schemas:
## Protocol mapping for Zigbee property
ProtocolMap-Zigbee-Propmap:
required:
- zigbee
type: object
properties:
zigbee:
required:
- endpointID
- clusterID
- attributeID
type: object
properties:
endpointID:
type: integer
format: int32
example: 1
clusterID:
type: integer
format: int32
example: 6
attributeID:
type: integer
format: int32
example: 16
type:
type: integer
format: int32
example: 1
ProtocolMap-Zigbee-Event:
allOf:
- $ref: '#/components/schemas/ProtocolMap-Zigbee-Propmap'
<CODE ENDS>
This document relies on SDF models described in [RFC9880], as such, we are grateful to the authors of this document for putting their time and effort into defining SDF in depth, allowing us to make use of it. The authors would also like to thank the ASDF working group for their excellent feedback and steering of the document.¶