ETSI TS 129 251 V15.3.0 (2019-10)

LTE; Gw and Gwn reference point for sponsored data connectivity (3GPP TS 29.251 version 15.3.0 Release 15)

RTS/TSGC-0329251vf30

General Information

• Status: Published
• Publication Date: 09-Oct-2019
• Technical Committee: 3GPP CT 3 - Interworking with external networks (formely CN3)
• Current Stage: 12 - Completion
• Completion Date: 10-Oct-2019

Standards Content (Sample)

TECHNICAL SPECIFICATION
LTE;
Gw and Gwn reference point for sponsored data connectivity
(3GPP TS 29.251 version 15.3.0 Release 15)

3GPP TS 29.251 version 15.3.0 Release 15 1 ETSI TS 129 251 V15.3.0 (2019-10)

Reference
RTS/TSGC-0329251vf30
Keywords
LTE
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3GPP TS 29.251 version 15.3.0 Release 15 2 ETSI TS 129 251 V15.3.0 (2019-10)
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Legal Notice
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3GPP TS 29.251 version 15.3.0 Release 15 3 ETSI TS 129 251 V15.3.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 6
2 References . 6
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 7
4 Gw reference point . 7
4.1 Overview . 7
4.2 Gw reference model . 7
4.3 Functional ele me nts . 8
4.3.1 PFDF . 8
4.3.2 PCEF . 8
4.4 Procedures over Gw reference point . 8
4.4.1 Request for PFDs ("Pull mode" and "Combination mode") . 8
4.4.2 Provisioning of PFDs ("Push mode"” and "Combination mode") . 9
5 Gwn reference point . 10
5.1 Overview . 10
5.2 Gwn reference model . 10
5.3 Functional ele me nts . 10
5.3.1 PFDF . 10
5.3.2 TDF . 10
5.4 Procedures over Gwn reference point . 11
6 Gw/Gwn protocol . 11
6.1 Introduction . 11
6.2 Transport layer . 11
6.3 Application delivery layer . 12
6.3.2 Resources and URI design . 12
6.3.2.1 General . 12
6.3.2.2 URI design for Pull mode . 13
6.3.2.3 URI design for Push mode . 13
6.3.3 HTTP request/response formats . 13
6.3.3.1 General . 13
6.3.3.2 GET /gwapplication/pfds/{application-identifier} . 14
6.3.3.3 GET /gwapplication/pfds?{query-parameters } . 15
6.3.3.4 GET /gwapplication/pfds . 17
6.3.3.5 POST /gwapplication/provisioning . 18
6.3.4 HTTP status codes . 20
6.3.5 Feature negotiation . 20
6.3.5.1 General . 20
6.3.5.2 HTTP custom headers . 21
6.3.5.2.1 3gpp-Optional-Features . 21
6.3.5.2.2 3gpp-Required-Features . 21
6.3.5.2.3 3gpp-Accepted-Features . 21
6.3.5.3 Precedence for HTTP custom headers . 22
6.4 Specific application communication . 22
6.4.1 General . 22
6.4.2 Content type . 22
6.4.3 JSON PFDs fields . 22
6.4.3.1 General . 22
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6.4.3.2 application-identifier . 22
6.4.3.3 void . 23
6.4.3.4 caching-time . 23
6.4.3.5 pfds . 23
6.4.3.6 pfd-identifier . 23
6.4.3.7 flow-descriptions . 23
6.4.3.8 urls. 23
6.4.3.9 domain-names . 24
6.4.4 JSON provisioning fields . 24
6.4.4.1 General . 24
6.4.4.2 notification-flag . 24
6.4.4.3 removal-flag . 24
6.4.4.4 allowed-delay . 24
6.4.4.5 partial-flag . 24
6.4.5 JSON errors and informational response fields . 25
6.4.5.1 General . 25
6.4.5.2 error-tag . 25
6.4.6 JSON report fields . 25
6.4.6.1 General . 25
6.4.6.2 pfd-reports . 25
6.4.6.3 pfd-failure-code . 26
6.5 The discovery of PCEF/TDF and PFDF . 26
6.5.1 PCEF/TDF discovery . 26
6.5.2 PFDF discovery . 26
7 Secure communication . 26
Annex A (normative): JSON Schema . 27
A.1 PFDs schema . 27
A.2 Provisioning schema. 28
A.3 Error and Informational response schema . 29
Annex B (informative): Call Flows . 32
B.1 General . 32
B.2 Request for PFDs (“Pull mode”) . 32
B.3 Provisioning of PFDs (“Push mode”) . 32
B.4 Provisioning of PFDs by Push with Notifications . 33
Annex C (informative): Change history . 35
History . 36

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3GPP TS 29.251 version 15.3.0 Release 15 5 ETSI TS 129 251 V15.3.0 (2019-10)
Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
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1 Scope
The present document provides the stage 3 specification of the Gw and Gwn reference points. The functional
requirements and the stage 2 specifications of the Gw and Gwn reference points are specified in 3GPP TS 23.203 [2].
The Gw reference point lies between the Packet Flow Description Function (PFDF) and the Policy and Charging
Enforcement Function (PCEF). The Gwn reference point lies between the Packet Flow Description Function (PFDF)
and the Traffic Detection Function (TDF).
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.203: “Policy and charging control architecture”.
[3] 3GPP TS 29.213: "Policy and Charging Control signalling flows and QoS parameter mapping"
[4] 3GPP TS 23.682: "Architecture enhancements to facilitate communications with packet data
networks and applications".
[5] 3GPP TS 29.212: "Policy and Charging Control (PCC); Reference points".
[6] IETF RFC 793: "Transmission Control Protocol".
[7] Void.
[8] 3GPP TS 33.210: "3G security; Network Domain Security (NDS); IP network layer security".
[9] IETF RFC 2818: "HTTP Over TLS".
[10] IETF RFC 3986: "Uniform Resource Identifier (URI): Generic Syntax"
[11] IETF RFC 7159: "The JavaScript Object Notation (JSON) Data Interchange Format".
[12] IETF draft-newton-json-content-rules-09: "A Language for Rules Describing JSON Content".
NOTE: This individual draft will not further progress in IETF. It is available from the following link:
https://www.ietf.org/archive/id/draft-newton-json-content-rules-09.txt.
[13] IETF RFC 6733: "Diameter Base Protocol".
[14] 3GPP TS 29.250: "Nu reference point between SCEF and PFDF for sponsored data connectivity".
[15] 3GPP TS 29.155: "Traffic steering control; Representational state transfer (REST) over St
reference point".
[16] IETF RFC 7230: "Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing".
[17] IETF RFC 7231: "Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content".
[18] IETF RFC 7232: "Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests".
[19] IETF RFC 7233: "Hypertext Transfer Protocol (HTTP/1.1): Range Requests".
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[20] IETF RFC 7234: "Hypertext Transfer Protocol (HTTP/1.1): Caching".
[21] IETF RFC 7235: "Hypertext Transfer Protocol (HTTP/1.1): Authentication".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A
term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].
rd
Packet Flow Description (PFD): A set of information enabling the detection of application traffic provided by a 3
party service provider (from 3GPP TS 23.203 [2]).
Pull mode: A mode used between the PCEF/TDF and the PFDF where the PFDs are sent by the PFDF at reception of
an HTTP request from the PCEF/TDF.
Push mode: A mode used between the PCEF/TDF and the PFDF where the PFDs and/or notification of PFD deletion
are sent by the PFDF in an HTTP request to the PCEF/TDF.
Combination mode: A mode used between the PCEF/TDF and the PFDF where both pull and push exist. This mode
allows the PFDF to send the PFDs at reception of an HTTP request from the PCEF/TDF and provision PFD changes
(creation/update/deletion) and/or notification of PFD creation/update/deletion in the HTTP request to the PCEF/TDF.
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An
abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
3GPP TR 21.905 [1].
JSON JavaScript Object Notation
PCEF Policy and Charging Enforcement Function
PFD Packet Flow Description
PFDF Packet Flow Description Function
SCEF Service Capability Exposure Function
TDF Traffic Detection Function
4 Gw reference point
4.1 Overview
The Gw reference point is located between the Packet Flow Description Function (PFDF) and the Policy and Charging
Enforcement Function (PCEF). The Gw reference point is used for provisioning and removal of PFDs from the PFDF to
the PCEF and reporting the handling result of PFDs from the PCEF to the PFDF.
The stage 2 level requirements for the Gw reference point are defined in 3GPP TS 23.203 [2].
4.2 Gw reference model
The Gw reference point is defined between the PFDF and the PCEF. The relationships between the different functional
entities involved are depicted in figure 4.2.1. The overall PCC architecture is depicted in subclause 3a of
3GPP TS 29.213 [3].
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Gw
PFDF
PCEF
Figure 4.2.1: Gw reference model
4.3 Functional elements
4.3.1 PFDF
The PFDF (Packet Flow Description Function) is a functional element which stores PFDs associated with application
identifier (s) and transfers them to the PCEF via Gw interface to enable the PCEF to perform accurate application
rd
detection when the PFDs are managed by a 3 party service provider.
The PFDF receives PFDs for the corresponding application identifier (s) from the SCEF as defined in
3GPP TS 23.682 [4]and 3GPP TS 29.250 [14].
4.3.2 PCEF
The PCEF (Policy and Charging Enforcement Function) funtionality defined in subclause 4.4.2 of 3GPP TS 29.212 [5]
shall be applied. In addition, the PCEF shall support the management of PFDs provisioned by the PFDF. The
application detection filter may be extended with the PFDs provided by the PFDF.
4.4 Procedures over Gw reference point
When the PFDF is deployed and the management of PFDs is supported by the PCEF, the mode of PFDs management
shall be consistently configured in one PLMN, it may be:
- Pull mode only, or
- Push mode only, or
- Combination mode.
4.4.1 Request for PFDs ("Pull mode" and "Combination mode")
At the time a PCC Rule with an application identifier for which PFDs provisioned by the PFDF are not available is
activated or provisioned, or when the caching timer for an application identifier elapses and a PCC Rule for the
application identifier is still active, the PCEF shall request all PFDs for the application identifier from the PFDF.
The PCEF shall send an HTTP GET message to the PFDF to retrieve the PFDs for one or more application identifier(s)
as defined in subclauses 6.3.3.2, 6.3.3.3 and 6.3.3.4.
Upon receipt of the HTTP request for the pull operation, the PFDF shall respond to the PCEF indicating whether the
pull operation was successful or not by using one of the HTTP status codes; if the pull operation is successful, the
PFDF :
- shall provide the PFDs of the specified application identifier(s) from the request within the body of the HTTP
response; and
- if there are caching time value(s) configured for any of the specified application identifier(s), shall set the
caching-time to the caching time value(s) for those application identifier(s) in the body of the HTTP response.
The PCEF shall install, update or remove the received PFD(s) for the application identifier(s).
The PCEF shall also for each application identifier start a caching timer with a value
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- according to the received caching time value for that application identifier, if such a value is received for that
application identifier; or
- otherwise with a default caching time value configured in the PCEF.
NOTE 1: The PCEF(s) and the PFDF(s) within an operator network are configured with the same default caching
time value to be applied for all application identifiers.
NOTE 2: In the combination mode, the HTTP POST message from the PFDF does not impact the running caching
timer of an application identifier.
When the PCEF removes the last PCC rule that refers to the corresponding application identifier, or when the caching
timer expires and no PCC rule refers to the application identifier, the PCEF may remove the PFD(s) related with the
application identifier.
The PFDs retrieved from PFDF take precedence over any PFDs pre-configured in the PCEF. If all PFDs retrieved from
the PFDF are removed for an application identifier, the pre-configured PFDs shall be applied again for the application
identifier.
4.4.2 Provisioning of PFDs ("Push mode"” and "Combination mode")
The PFDF may create, update or remove one or multiple PFDs associated with application identifier(s) to the PCEF.
When the request for creation, update, or removal for an application identifier(s) is received from the SCEF, for the
Push mode, the PFDF shall for each PCEF it serves:
- immediately send to the PCEF an HTTP POST message including the provisioned changes of one or more
application identifiers as specified in subclause 6.3.3.5, or
- wait for a period shorter than the allowed delay ( e.g.to aggregate all the PFDs for several application) , then
send to the PCEF an HTTP POST message including the provisioned changes.
For the Combination mode, the PFDF may for each PCEF it serves wait for a period shorter than the allowed delay (e.g.
to aggregate all the PFDs for several application) and, if no HTTP GET request for that application identifier is received
during the waiting time, then send an HTTP POST message including the provisioned changes and/or notification of
PFD creation/update for that application identifier as specified in subclause 6.3.3.5.
NOTE 1: In the combination mode, the PFDF can check the received allowed delay against the caching time as
specified in subclause 4.4.1 of 3GPP TS 29.250 [14], in order to utilize the pull procedure.
When the PCEF receives the HTTP POST message, the PCEF shall
- for an application identifier(s) where no flag is provided, remove the all existing all PFD(s) (if available) and
install all the new provided PDF(s).
- for an application identifier(s) where the removal-flag is also provided and set to true, delete the existing
PFD(s);
- for an application identifier(s) where partial-flag is also provided and set to true
- install a new PFD(s) if the new PFD(s) with a new PFD identifier(s) is received,
- update an existing PFD(s) if a new PFD(s) with the same PFD identifier(s) is recevied, and/or
- delete an existing PFD(s) if the same PFD identifier(s) without any content is received;
- acknowledge the HTTP POST message by sending a corresponding HTTP response with the appropriate status
code (200 OK for success) as described in subsclause 6.3.4; and
- retrieve the PFDs for the corresponding application identifier(s) as defined in subclause 4.4.1 either immediately
if the allowed-delay is not provided, or within the provided allowed-delay for the application identifier(s) where
the notification-flag is included and set to true.
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NOTE 2: It depends on the implementation whether the PCEF initiates separate pull requests to retrieve the PFDs
for different application identifier(s) within the allowed-delay. The decision to send PFD, and/or
notification of PFD creation/update/deletion for certain application identifier on the PFDF is based on the
operator policy.
NOTE 3: In the push mode, the PFDF can be configured with the list of PCEFs per application identifier(s).
NOTE 4: The caching timer is not applicable for the PCEF/TDF in Push mode.
5 Gwn reference point
5.1 Overview
The Gwn reference point is located between the Packet Flow Description Function (PFDF) and the Traffic Detection
Function (TDF). The Gwn reference point enables transport of PFDs from the PFDF to the TDF for a particular
Application Identifier or for a set of Application Identifiers.
The Gwn reference point supports the following functions:
- Creation, updating and removal of individual or the whole set of PFDs from the PFDF to the TDF.
- Confirmation of creation, updating and removal of PFDs from the TDF to the PFDF.
NOTE: The interaction between the PFDF and the TDF is not related to any IP-CAN session.
The stage 2 level requirements for the Gwn reference point are defined in 3GPP TS 23.203 [2].
5.2 Gwn reference model
The Gwn reference point is defined between the PFDF and the TDF. The relationships between the different functional
entities involved are depicted in figure 5.2.1. The overall PCC architecture is depicted in subclause 3a of
3GPP TS 29.213 [3].
Gwn
TDF PFDF
Figure 5.2.1: Gwn reference model
5.3 Functional elements
5.3.1 PFDF
Subclause 4.3.1 is applicable with the clarification that the TDF replaces the PCEF and Gwn interface replaces Gw
interface.
5.3.2 TDF
The TDF (Traffic Detection Function) funtionality defined in subclause 4b.4.2 of 3GPP TS 29.212 [5] shall be applied.
In addition, the TDF shall support the management of PFDs provisioned by the PFDF.
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5.4 Procedures over Gwn reference point
The procedures in subclause 4.4 are applicable with the clarification that the TDF replaces the PCEF in those
procedures.
6 Gw/Gwn protocol
6.1 Introduction
The following layers of the protocol stack for the Gw/Gwn reference point between PCEF/TDF and PFDF are described
in subclauses:
- TCP as defined in IETF RFC 793 [6] provides the communication service at the transport layer.
- An optional communication security layer can be added between the transport and the application delivery layer
(see clause 7).
- The application delivery layer provides the transport of the specific application communication data using HTTP
as defined in IETF RFC 7230 [16], IETF RFC 7231 [17], IETF RFC 7232 [18], IETF RFC 7233 [19],
IETF RFC 7234 [20] and IETF RFC 7235 [21].
- The specific application communication layer constitutes the transport of the JSON content type.
Figure 6.1.1 illustrates the protocol stack of the RESTful Gw/Gwn reference point.

Figure 6.1.1: Protocol stack of the Gw/Gwn reference point
6.2 Transport layer
HTTP is layered over TCP, which provides a reliable transport.
If the "Pull mode" is deployed, then the PCEF/TDF shall act as an HTTP client and the PFDF shall act as an HTTP
server. In this case, the PCEF/TDF shall initiate a TCP connection with the PFDF.
If the "Push mode" is deployed, then the PFDF shall act as an HTTP client and the PCEF/TDF shall act as an HTTP
server. In this case, the PFDF shall initiate a TCP connection with the PCEF/TDF.
If the "Combination mode" is deployed, then
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- for pull request, the HTTP roles and TCP session establishment as described above for the "Pull mode" apply.
- for push request (with or without notification), the HTTP roles and TCP session establishment as described
above for the "Push mode" apply.
6.3 Application delivery layer
The application delivery layer shall use RESTful HTTP.
The application delivery layer provides the following services:
- Retrieval of the PFDs from the PFDF
- Provisioning of the PFDs by the PFDF
- Notification sent from PFDF to the PCEF/TDF to indicate PFD changes related to application identifiers being
created, updated or deleted
In order to retrieve the PFD for a specific application identifier, the PFDF shall send an HTTP GET message including
the application identifier as a path element of the request URI as specified in subclause 6.3.3.2.
In order to retrieve the PFDs for a set of application identifiers, the PCEF/TDF shall send an HTTP GET message to the
PFDF including the application identifier(s) as the query parameters in the URI as specified in subclause 6.3.3.3.
In order to retrieve all PFDs, the PCEF/TDF may omit the ‘?’ and {query parameters} in the HTTP GET message’s
URI as specified in subclause 6.3.3.4.
If the PFDF needs to provision PFDs for a set of application identifier(s) (creation/update/deletion) to the PCEF/TDF,
the PFDF shall send an HTTP POST message, which includes the provisioned changes and/or the notifications of
impacted application identifiers as described in subclause 6.3.3.5.
6.3.1 Methods
Methods indicate to the server what action has to be performed. Every HTTP request message has a method. The
following HTTP methods can be used:
- GET: Used by the PCEF/TDF to retrieve the PFDs information for a set of application identifier(s). The server
returns the PFDs representation within the body of the response.
- POST: Used by the PFDF to provision or notify PFDs changes for a set of application identifiers(s). The request
URI defines the address responsible for the management of the PFDs provisioning as a controller resource.
Every HTTP request results in a response message that comes back with a status code and further information in its
body, if required. The HTTP request initiator waits for this response before initiating a further request.
6.3.2 Resources and URI design
6.3.2.1 General
The URI design shall be based on the structure defined in IETF RFC 3986 [10]:
scheme ":" hier-part [ "?" query ] [ "#" fragment ]
hier-part  = "//" authority path-abempty
/ path-absolute
/ path-rootless
/ path-empty
The scheme may be HTTP or HTTPS for the Gw/Gwn interface. Within a scheme the definition of names shall follow
the rules of HTTP URIs. Host and port are the main parts of the authority. The path element identifies the resources.
For the Gw/Gwn interface, the following required parts of the URI shall be used as follows:
- scheme: The application delivery layer protocol "http" or "https".
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- authority: It includes the server address and optionally a port as follows: host [":" port]
- path-absolute: The path-absolute should have the following ABNF: "/" mainapp "/" mainresource ["/"
resourcepath]. In this release:
- "mainapp" is "gwapplication".
- "mainresource" is defined in subclauses 6.3.2.2 and 6.3.2.3.
- "resourcepath" contains the path to identify the PFDs resource for a specific application identifier.
6.3.2.2 URI design for Pull mode
In pull mode, the PFDs in PFDF is a readable RESTful resource:
- "mainresource" is "pfds".
- "resourcepath" varies and is defined in subclauses 6.3.3.2, 6.3.3.3 and 6.3.3.4.
An example of the URI to identify the RESTful resource is: http://pfdfserver.example.com/gwapplication/pfds.
NOTE: A different resource path can be used when the Resource URI is preconfigured in the PCEF/TDF.
6.3.2.3 URI design for Push mode
In push mode, the PFDs management (associating/disassociating PFDs with application identifiers) in PCEF/TDF is a
controller resource that is responsible for processing push requests that involve provisioning and/or notifying a set of
changes for more than one set of PFDs for corresponding application identifiers atomically.
- "mainresource" shall be "provisioning".
- "resourcepath" is not applicable in push mode.
An example of the URI to identify the controller resource is http://pcefserver.example.com/gwapplication/provisioning.
NOTE: A different resource path can be used when the Resource URI is preconfigured in the PFDF.
6.3.3 HTTP request/response formats
6.3.3.1 General
The PFDs pull procedure is performed through HTTP transactions consisting of a request initiated by the PCEF/TDF
and its corresponding response provided by the PFDF. While the PFDs push procedure is initiated by the PFDF and
answered by the PCEF/TDF
Table 6.3.3.1-1 summarizes the content of the requests and responses. More detailed information is specified in the
corresponding subclauses as indicated in the table.
ETSI
3GPP TS 29.251 version 15.3.0 Release 15 14 ETSI TS 129 251 V15.3.0 (2019-10)
Table 6.3.3.1-1: Gw/Gwn requests/response summary table
Method Resource URI’s path Clause Request body Initiat Response body
Defined or
GET /gwapplication/pfds/{ap 6.3.3.2 None PCEF Successful response: The
plication-identifier} /TDF PFDF shall include the
(NOTE 1) representation of the
corresponding PDFs of the
specified application identifier in
the body of the response as per
Annex A.1
GET /gwapplication/pfds?{q 6.3.3.3 None PCEF Successful response: The
uery-parameters} /TDF PFDF shall include the
(NOTE 1) representation of the
corresponding PDFs for a set of
application identifier(s) in the
body of the response as per
Annex A.1
GET /gwapplication/pfds 6.3.3.4 None PCEF Successful response: The
(NOTE 1) /TDF PFDF shall include the
representation of the
corresponding PDFs for all
application identifier(s) in the
body of the response as per
Annex A.1
POST /gwapplication/provisio 6.3.3.5 Content-Type: PFDF Successful response: The
ning application/json PCEF/TDF may include
(NOTE 2) The PFDF may include informational data in the body of
PFDs content and/or the response as per Annex A.3
notification associated
with application
identifier(s) using the
schema defined in Annex
A.2.
NOTE 1: A different path from /gwapplication/pfds/ may be used when it is configured in the PCEF/TDF. In that case
the "path" part set in the different methods should use the configured one.
NOTE 2:  A different path from /gwapplication/provisioning may be used when it is configured in the PFDF. In that case
the "path" part set in the different methods should use the configured one.

6.3.3.2 GET /gwapplication/pfds/{application-identifier}
To retrieve the PFDs for a specific application identifier, the PCEF/TDF shall send an HTTP GET request to the PFDF
as follows:
- the request URI formatted as defined in subclause 6.3.2 with the "path" part set to:
/gwapplication/pfds/{application-identifier}, where the application-identifier is the application id with which the
PFDs are associated.
Upon receipt of the HTTP GET, the PFDF shall respond to the PCEF/TDF indicating whether the querying of the
resource was successful or not using one of the HTTP status codes as defined in subclause 6.3.4. If the resource exists,
the PFDF shall respond with an HTTP 200 OK status code and include the PFDs representation state within the body of
the response as defined in Annex A.1. If no resource was found, the PFDF shall respond with an HTTP 404 not found.
The PFDF shall also include the Content-Type header field set to "application/json".
If the PCEF/TDF receives the HTTP 404 not found status code, the PCEF/TDF shall remove all the PFD(s) of the
queried application identifier.
Below is an example of a corresponding HTTP GET:
GET /gwapplication/pfds/test-application-1 HTTP/1.1
Host: pfdfserver.example.com
ETSI
3GPP TS 29.251 version 15.3.0 Release 15 15 ETSI TS 129 251 V15.3.0 (2019-10)
Here is an example of a successful response :
HTTP/1.1 200 OK
Server: pfdfserver.example.com
Content-Type: application/json
Content-Length: …
{
"application-identifier":"test-application-1",

"caching-time":200000,
"pfds":[
{
"pfd-identifier":"pfd1",
"flow-descriptions":[
"permit in ip from 10.68.28.39 80 to any",
"permit out ip from any to 10.68.28.39 80"
]
},
{
"pfd-identifier":"pfd2",
"urls":[
"^http://test.example.com(/\\S*)?$"
]
}
]
}
6.3.3.3 GET /gwapplication/pfds?{query-parameters }
To retrieve the PFDs for a set of application identifier(s), the PCEF/TDF may send an HTTP GET request to the PFDF
as follows:
- The request URI formatted as defined in subclause
...