PCEP Extension for Flow Specification Version 2
draft-liu-pce-pcep-flowspec-v2-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Yao Liu | ||
| Last updated | 2026-02-01 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
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draft-liu-pce-pcep-flowspec-v2-00
PCE Y. Liu
Internet-Draft ZTE Corporation
Intended status: Experimental 1 February 2026
Expires: 5 August 2026
PCEP Extension for Flow Specification Version 2
draft-liu-pce-pcep-flowspec-v2-00
Abstract
Traffic flows may be categorized and described using "Flow
Specifications". RFC8955 defines the Flow Specification and
describes how Flow Specification components are used to describe
traffic flows. RFC8955 also defines how Flow Specifications may be
distributed in BGP to allow specific traffic flows to be associated
with routes. The flow specification protocol defined in RFC8955,
RFC8956, RFC9117 is called BGP flow specification version 1 (BGP
FSv1).
RFC9168 specifies a set of extensions to PCEP to support the
dissemination of Flow Specifications. This allows a PCE to indicate
what traffic should be placed on each path that it is aware of.
RFC9168 inherits the BGP Flow Spec registry and ordering rules as
well as the limitations in BGP FSv1.
This document proposes extensions to PCEP to add the support of Flow
Specification v2 to allow the user to order the flow specification
rules.
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 https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 5 August 2026.
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Copyright Notice
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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
3. Procedures for PCE Use of Flow Specification v2 . . . . . . . 4
4. PCE FlowSpecv2 Capability TLV . . . . . . . . . . . . . . . . 5
5. PCEP FLOWSPECv2 Object . . . . . . . . . . . . . . . . . . . 5
6. IP Basic Flow Filter TLV . . . . . . . . . . . . . . . . . . 8
7. IP Basic Flow Specification TLVs . . . . . . . . . . . . . . 9
8. Detailed Procedures . . . . . . . . . . . . . . . . . . . . . 10
8.1. Priorities and Overlapping Flow Specifications . . . . . 10
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
9.1. PCEP Objects . . . . . . . . . . . . . . . . . . . . . . 11
9.1.1. PCEP FLOWSPECv2 Object Flag Field . . . . . . . . . . 11
9.2. PCEP TLV Type Indicators . . . . . . . . . . . . . . . . 12
9.3. IP Basic Flow Specification TLV Type Indicators . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13
11. Manageability Considerations . . . . . . . . . . . . . . . . 13
11.1. Control of Function and Policy . . . . . . . . . . . . . 13
11.2. Information and Data Models . . . . . . . . . . . . . . 13
11.3. Liveness Detection and Monitoring . . . . . . . . . . . 13
11.4. Verify Correct Operations . . . . . . . . . . . . . . . 13
11.5. Requirements On Other Protocols . . . . . . . . . . . . 14
11.6. Impact On Network Operations . . . . . . . . . . . . . . 14
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
12.1. Normative References . . . . . . . . . . . . . . . . . . 14
12.2. Informative References . . . . . . . . . . . . . . . . . 15
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
BGP flow specification as defined by [RFC8955], [RFC8956], [RFC9117]
specifies the distribution of traffic filter policy (traffic filters
and actions) via BGP to a mesh of BGP peers. The traffic filter
policy is applied when packets are received on a router with the flow
specification function turned on. The flow specification protocol
defined in [RFC8955], [RFC8956], [RFC9117] is called BGP flow
specification version 1 (BGP FSv1).
To address the limitations of BGP FSv1, [I-D.ietf-idr-flowspec-v2]
specifies version 2 of the BGP flow specification protocol (BGP
FSv2). [I-D.ietf-idr-fsv2-ip-basic] provides the basic FSv2
framework specification for transmitting user-ordered IP filters in
the FSv2 NLRI with Extended Community to specify actions.
[RFC9168] specifies a set of extensions to PCEP to support
dissemination of Flow Specifications. This allows a PCE to indicate
what traffic should be placed on each path that it is aware of.
[I-D.ietf-pce-pcep-l2-flowspec] further extends the support for
Ethernet Layer 2 (L2) and Layer 2 Virtual Private Network (L2VPN)
traffic filtering rules in PCEP Flow Specifications.
The current PCEP Extensions for Flow Specification [RFC9168]
[I-D.ietf-pce-pcep-l2-flowspec] inherit the BGP Flow Spec registry
and ordering rules in BGP FSv1 [RFC8955] [RFC8956], so it has the
same limitations as BGP FSv1 in the aspect of flow filtering as
analyzed in [I-D.ietf-idr-flowspec-v2], that is, lack of consistent
TLV encoding prevented extension of encodings and inability to allow
user defined order for filtering rules. In terms of the action
associated with the Flow Specification, PCEP Flow Specification is
not affected by shortcoming of inability to order actions to provide
deterministic interactions or to allow users to define order for
actions in BGPv1, since there is only one action that is applicable
in the PCEP context (that is, directing the matching traffic to the
identified LSP).
This document proposes extensions to PCEP to add the support of Flow
Specification v2 to allow the user to order the flow specification
rules.
Currently, only the IP Basic Filters are considered in this document.
Future version may add the support of MPLS/L2/SFC/Tunneled Flow
Specifications with the development of BGP FSv2
[I-D.ietf-idr-flowspec-v2].
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A new object called the FLOWSPECv2 object is defined in this
document. The flow filtering rules indicated by the Flow
Specifications are mainly defined by BGP Flow version 2
Specifications in in [I-D.ietf-idr-flowspec-v2] and
[I-D.ietf-idr-fsv2-ip-basic]. And the coexistence of FLOWSPEC object
defined in [RFC9168] and FLOWSPECv2 object are also considered.
2. Terminology
This document uses the following terms defined in [RFC5440]: PCC,
PCE, PCEP Peer.
The following term from [RFC8955] is used frequently throughout this
document:
A Flow Specification is an n-tuple consisting of several matching
criteria that can be applied to IP traffic. A given IP packet is
said to match the defined Flow Specification if it matches all the
specified criteria.
This document uses the following terms defined in
[I-D.ietf-idr-flowspec-v2]: BGP FSv1, BGP FSv2.
The term "PCEP FSv1" is used to refer to the PCEP flow specification
defined in [RFC9168], and "PCEP FSv2" is used to indicate the PCEP
flow specification extensions proposed in this document.
2.1. Requirements Language
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.
3. Procedures for PCE Use of Flow Specification v2
The steps in the setup and use of LSPs section 3 of [RFC9168] defines
the procedures for PCE use of Flow Specifications. For PCEP Flow
Specification v2, the steps in the setup and use of LSPs follow the
same specification defined in section 3.1 of [RFC9168] respectively.
As for the elements of the procedure, this document also follows the
specification in section 3.2 of [RFC9168] except that:
* a new "PCE FlowSpecv2 Capability TLV" is defined in this document
to indicate the ability to support Flow Specifications can be
indicated in the PCEP Open message;
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* a new PCE-CAP-FLAGS sub-TLV bit, the "FlowSpecv2 Capable flag" is
defined in this document to indicate that an advertising PCE
supports the procedures of PCE FlowSpecv2 defined in this
document;
* a new "PCEP FLOWSPECv2 object" is defined in this document to
carry version 2 of Flow Specifications in PCEP messages.
The following sections describe these points.
4. PCE FlowSpecv2 Capability TLV
The PCE-FLOWSPECv2-CAPABILITY TLV is an optional TLV that can be
carried in the OPEN object [RFC5440] to exchange the PCE FlowSpecv2
capabilities of the PCEP speakers.
The format of the PCE-FLOWSPECv2-CAPABILITY TLV follows the format of
all PCEP TLVs as defined in [RFC5440] and is shown in Figure 1.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length=2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value=0 | Padding |
+---------------------------------------------------------------+
Figure 1: PCE-FLOWSPECv2-CAPABILITY TLV Format
The type of the PCE-FLOWSPECv2-CAPABILITY TLV is TBD1, and it has a
fixed length of 2 octets. The Value field MUST be set to 0 and MUST
be ignored on receipt. The two bytes of padding MUST be set to zero
and ignored on receipt.
The inclusion of this TLV in an OPEN object indicates that the sender
can perform FlowSpecv2 handling as defined in this document.
5. PCEP FLOWSPECv2 Object
The PCEP FLOWSPECv2 object defined in this document is compliant with
the PCEP object format defined in [RFC5440]. It is OPTIONAL in the
PCReq, PCRep, PCErr, PCInitiate, PCRpt, and PCUpd messages and MAY be
present zero, one, or more times. Each instance of the object
specifies a separate traffic flow.
The PCEP FLOWSPECv2 object MAY carry FlowSpecv2 filter rules encoded
in a Flow Filter TLV as defined in Section 6.
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The FLOWSPECv2 Object-Class is TBD2.
The FLOWSPECv2 Object-Type is TBD3.
The format of the body of the PCEP FLOWSPECv2 object is shown in
Figure 2.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FS-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AFI | Reserved | Flags |L|R|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: PCEP FLOWSPECv2 Object Body Format
FS-ID (32 bits): A PCEP-specific identifier for the FlowSpec
information. A PCE or PCC creates an FS-ID for each FlowSpec that
it originates, and the value is unique within the scope of that
PCE or PCC and is constant for the lifetime of a PCEP session.
All subsequent PCEP messages can identify the FlowSpec using the
FS-ID. The values 0 and 0xFFFFFFFF are reserved and MUST NOT be
used. Note that [I-D.gont-numeric-ids-sec-considerations] gives
advice on assigning transient numeric identifiers such as the FS-
ID so as to minimize security risks.
AFI (16 bits): Address Family Identifier as used in BGP [RFC4760].
AFI=1 for IPv4, AFI=2 for IPv6, AFI=6 for L2, AFI=25 for L2VPN,
and AFI=31 for SFC as per [I-D.ietf-idr-flowspec-v2].
Reserved (8 bits): MUST be set to zero on transmission and ignored
on receipt.
Flags (8 bits): Two flags are currently assigned:
R bit: The Remove bit is set when a PCEP FLOWSPECv2 object is
included in a PCEP message to indicate removal of the Flow
Specification from the associated tunnel. If the bit is clear,
the Flow Specification is being added or modified.
L bit: The Longest Prefix Match (LPM) bit is set to indicate that
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the Flow Specification is to be installed as a route subject to
LPM forwarding. If the bit is clear, the Flow Specification
described by the IP Basic Flow Filter TLV (see Section 6) is to
be installed as a Flow Specification. If the bit is set, only
IP Basic Flow Filter TLV that describe IPv4 or IPv6
destinations are meaningful in the Flow Filter TLV, and others
are ignored. If the L is set and the receiver does not support
the use of Flow Specifications that are present in the IP Basic
Flow Filter TLV for the installation of a route subject to LPM
forwarding, then the PCEP peer MUST respond with a PCErr
message with Error-Type 30 (FlowSpec Error) and Error-value 5
(Unsupported LPM Route).
Unassigned bits MUST be set to zero on transmission and ignored on
receipt.
If the PCEP speaker receives a message with the R bit set in the
FLOWSPECv2 object and the Flow Specification identified with an FS-ID
does not exist, it MUST generate a PCErr with Error-Type 30 (FlowSpec
Error) and Error-value 4 (Unknown FlowSpec).
If the PCEP speaker does not understand or support the AFI in the
FLOWSPEC message, the PCEP peer MUST respond with a PCErr message
with Error-Type 30 (FlowSpec Error) and Error-value 2 (Malformed
FlowSpec).
The following TLVs can be used in the FLOWSPEC object:
Speaker Entity Identifier TLV: As specified in [RFC8232], the
SPEAKER-ENTITY-ID TLV encodes a unique identifier for the node
that does not change during the lifetime of the PCEP speaker.
This is used to uniquely identify the FlowSpec originator and thus
is used in conjunction with the FS-ID to uniquely identify the
FlowSpec information. This TLV MUST be included. If the TLV is
missing, the PCEP peer MUST respond with a PCErr message with
Error-Type 30 (FlowSpec Error) and Error-value 2 (Malformed
FlowSpec). If more than one instance of this TLV is present, the
first MUST be processed, and subsequent instances MUST be ignored.
IP Basic Flow Filter TLV (variable): One TLV MAY be included. The
Flow Filter TLV is OPTIONAL when the R bit is set.
The IP Basic Flow Filter TLV MUST be present when the R bit is clear.
If the TLV is missing when the R bit is clear, the PCEP peer MUST
respond with a PCErr message with Error-Type 30 (FlowSpec Error) and
Error-value 2 (Malformed FlowSpec).
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6. IP Basic Flow Filter TLV
One new PCEP TLV is defined to convey Flow Specification version 2
filtering rules that specify what traffic is carried on a path. The
TLV follows the format of all PCEP TLVs as defined in [RFC5440].
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Order |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// sub-TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: IP Basic Flow Filter TLV
The Type field values come from the code point space for PCEP TLVs
and has the value TBB4 for IP Basic Flow Filter TLV.
The value field contains an order field, it is a 4-octet field with a
value 1-N following the semantic . The value 0 (zero) is invalid, if
the value 0 is received, the PCEP peer MUST respond with a PCErr
message with Error-Type 30 (FlowSpec Error) and Error-value 2
(Malformed FlowSpec).
(Currently, the dependency filter chain field in the IP Basic TLV
[I-D.ietf-idr-fsv2-ip-basic] is not carried in IP Basic Flow Filter
TLV defined in this document since this field is set all zero for the
IP Basic Filter rules in [I-D.ietf-idr-fsv2-ip-basic])
The Value field of the TLV contains one or more sub-TLVs (the Flow
Specification TLVs) as defined in Section 7, and they represent the
complete definition of a IP Flow Specification for traffic to be
placed on the tunnel. This tunnel is indicated by the PCEP message
in which the PCEP FLOWSPECV2 object is carried. The set of Flow
Specification TLVs in a single instance of a Flow Filter TLV is
combined to indicate the specific Flow Specification.
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7. IP Basic Flow Specification TLVs
The IP Basic Flow Filter TLV carries one or more IP Basic Flow
Specification TLVs. IP Basic Flow Specification TLV follows the
format of all PCEP TLVs as defined in [RFC5440]. However, the Type
values are selected from a separate IANA registry rather than from
the common PCEP TLV registry.
Type values are chosen so that there can be commonality with Flow
Specifications defined for use with BGP [I-D.ietf-idr-fsv2-ip-basic].
This is possible because the BGP Flow Spec version 2 encoding uses a
single octet to encode the type, whereas PCEP uses 2 octets. Thus,
the space of values for the Type field is partitioned as shown in
Table 1.
+===========+=======================================+
| Range | Description |
+===========+=======================================+
| 0-255 | Per BGP Flow Spec registry defined by |
| | [I-D.ietf-idr-fsv2-ip-basic]. |
| | |
| | Not to be allocated in this registry. |
+-----------+---------------------------------------+
| 256-65535 | New PCEP Flow Specifications |
| | allocated according to the registry |
| | defined in this document. |
+-----------+---------------------------------------+
Table 1: IP Basic Flow Specification TLV Type Ranges
[I-D.ietf-idr-fsv2-ip-basic] is the reference for the "BGP FSv2
Component Types" registry and defines the allocations it contains.
The content of the Value field in each TLV is specific to the type/
AFI and describes the parameters of the Flow Specification. The
definition of the format of many of these Value fields is inherited
from BGP FSv2 specifications for basic
IP[I-D.ietf-idr-fsv2-ip-basic], but it may also be inherited from
future BGP specifications.
When used in other protocols (such as BGP), these Flow Specifications
are also associated with actions to indicate how traffic matching the
Flow Specification should be treated. In PCEP, however, the only
action is to associate the traffic with a tunnel and to forward
matching traffic onto that path, so no encoding of an action is
needed.
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8. Detailed Procedures
When using the protocol extensions defined in this document, the
following produres of PCEP FSv1 defined in [RFC5440] apply as well.
* Default Behavior and Backward Compatibility: same as [RFC5440]
section 8.1.
* Composite Flow Specifications: same as [RFC5440] section 8.2.
* Modifying Flow Specifications: same as [RFC5440] section 8.3.
* Multiple Flow Specifications: same as [RFC5440] section 8.4 for
the the PCEP FLOWSPECv2 object.
* Adding and Removing Flow Specifications: same as [RFC5440] section
8.5 for the the PCEP FLOWSPECv2 object.
Besides, the following subsections outline some additional procedures
for using the protocol extensions defined in this document.
8.1. Priorities and Overlapping Flow Specifications
Flow Specifications can overlap. For example, two different Flow
Specifications may be identical except for the length of the prefix
in the destination address. In these cases, the PCC must determine
how to prioritize the Flow Specifications so as to know which path to
assign packets that match both Flow Specifications. That is, the PCC
must assign a precedence to the Flow Specifications so that it checks
each incoming packet for a match in a predictable order.
[I-D.ietf-idr-flowspec-v2] specifies the ordering of FSv2 Filters and
it provides rules and features to keep filters in a deterministic
order between FSv1 and FSv2. PCCs MUST apply the same ordering rules
as defined in [I-D.ietf-idr-flowspec-v2].
When the PCC receives both the PCEP FLOWSPEC object and PCEP
FLOWSPECv2 object, the FSv1 rules are added after FSv2 rules
FSv2 rules are ordered based on user-specified order. The user-
specified order is carried in the FSv2 NLRI and a numerical lower
value takes precedence over a numerically higher value. For rules
received with the same order value, the FSv1 rules apply (order by
component type and then by value of the components).
An implementation that receives a PCEP message carrying a Flow
Specification that it cannot resolve against other Flow
Specifications already installed (for example, because the new Flow
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Specification has irresolvable conflicts with other Flow
Specifications that are already installed) MUST respond with a PCErr
message with Error-Type 30 (FlowSpec Error) and Error-value 3
(Unresolvable Conflict) and MUST NOT install the Flow Specification.
9. IANA Considerations
This document requests that IANA allocate code points for the
protocol elements defined in this document.
9.1. PCEP Objects
Each PCEP object has an Object-Class and an Object-Type. IANA
maintains a subregistry called "PCEP Objects". IANA is requested to
make an assignment from this subregistry as follows:
+==============+==========+=======================+============+
| Object-Class | Name | Object-Type | Reference |
| Value | | | |
+==============+==========+=======================+============+
| TBD5 | FLOWSPEC | 0: Reserved | [This.I-D] |
| | +-----------------------+------------+
| | | 1: Flow Specification | [This.I-D] |
| | | version 2 | |
+--------------+----------+-----------------------+------------+
Table 2: PCEP Objects Subregistry Additions
9.1.1. PCEP FLOWSPECv2 Object Flag Field
This document requests that a new subregistry, "FLOWSPEC Object Flag
Field", be created within the "Path Computation Element
Protocol(PCEP) Numbers" registry to manage the Flag field of the
FLOWSPECv2 object. New values are to be assigned by Standards Action
[RFC8126]. Each bit should be tracked with the following qualities:
* Bit number (counting from bit 0 as the most significant bit)
* Capability description
* Defining RFC
The initial population of this registry is as follows:
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+=====+================+============+
| Bit | Description | Reference |
+=====+================+============+
| 0-5 | Unassigned | |
+-----+----------------+------------+
| 6 | LPM (L bit) | [This.I-D] |
+-----+----------------+------------+
| 7 | Remove (R bit) | [This.I-D] |
+-----+----------------+------------+
Table 3: Initial Contents of the
FLOWSPEC Object Flag Field
Registry
9.2. PCEP TLV Type Indicators
IANA maintains a subregistry called "PCEP TLV Type Indicators". IANA
is requested to make an assignment from this subregistry as follows:
+=======+===============================+============+
| Value | Description | Reference |
+=======+===============================+============+
| TBD1 | PCE-FLOWSPECv2-CAPABILITY TLV | [This.I-D] |
+-------+-------------------------------+------------+
| TBD4 | IP Basic FLOW FILTER TLV | [This.I-D] |
+-------+-------------------------------+------------+
Table 4: PCEP TLV Type Indicators Subregistry
Additions
9.3. IP Basic Flow Specification TLV Type Indicators
IANA is requested to create a new subregistry called the "PCEP Flow
Specification TLV Type Indicators" registry.
Allocations from this registry are to be made according to the
following assignment policies [RFC8126]:
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+=============+===================================+
| Range | Registration Procedures |
+=============+===================================+
| 0-255 | Reserved - must not be allocated. |
| | |
| | Usage mirrors the BGP Flow Spec |
| | registry [RFC8955] [RFC8956]. |
+-------------+-----------------------------------+
| 256-64506 | Specification Required |
+-------------+-----------------------------------+
| 64507-65531 | First Come First Served |
+-------------+-----------------------------------+
| 65532-65535 | Experimental Use |
+-------------+-----------------------------------+
Table 5: Registration Procedures for the PCEP
Flow Specification TLV Type Indicators
Subregistry
10. Security Considerations
TBA
11. Manageability Considerations
11.1. Control of Function and Policy
[RFC9168] describe the management of multiple flowspecs as well as
control via configurations and policies. This is applicable to the
Tunneled flowspec defined in this document.
11.2. Information and Data Models
The PCEP YANG module [RFC9826] would need to be augmented to cover
tunneled flowspec.
11.3. Liveness Detection and Monitoring
Mechanisms defined in this document do not imply any new liveness
detection and monitoring requirements in addition to those already
listed in [RFC5440].
11.4. Verify Correct Operations
Mechanisms defined in this document do not imply any new operation
verification requirements in addition to those already listed in
[RFC9168].
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11.5. Requirements On Other Protocols
Mechanisms defined in this document do not imply any new requirements
on other protocols.
11.6. Impact On Network Operations
Mechanisms defined in this document do not have any new impact on
network operations in addition to those already listed in [RFC9168].
12. References
12.1. Normative References
[I-D.ietf-idr-flowspec-v2]
Hares, S., Eastlake, D. E., Yadlapalli, C., and S.
Maduschke, "BGP Flow Specification Version 2", Work in
Progress, Internet-Draft, draft-ietf-idr-flowspec-v2-04,
28 April 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-idr-flowspec-v2-04>.
[I-D.ietf-idr-fsv2-ip-basic]
Hares, S., Eastlake, D. E., Dong, J., Yadlapalli, C., and
S. Maduschke, "BGP Flow Specification Version 2 - for
Basic IP", Work in Progress, Internet-Draft, draft-ietf-
idr-fsv2-ip-basic-03, 3 March 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-idr-
fsv2-ip-basic-03>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007,
<https://www.rfc-editor.org/info/rfc4760>.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/info/rfc5440>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
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[RFC8232] Crabbe, E., Minei, I., Medved, J., Varga, R., Zhang, X.,
and D. Dhody, "Optimizations of Label Switched Path State
Synchronization Procedures for a Stateful PCE", RFC 8232,
DOI 10.17487/RFC8232, September 2017,
<https://www.rfc-editor.org/info/rfc8232>.
[RFC8955] Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
Bacher, "Dissemination of Flow Specification Rules",
RFC 8955, DOI 10.17487/RFC8955, December 2020,
<https://www.rfc-editor.org/info/rfc8955>.
[RFC8956] Loibl, C., Ed., Raszuk, R., Ed., and S. Hares, Ed.,
"Dissemination of Flow Specification Rules for IPv6",
RFC 8956, DOI 10.17487/RFC8956, December 2020,
<https://www.rfc-editor.org/info/rfc8956>.
[RFC9168] Dhody, D., Farrel, A., and Z. Li, "Path Computation
Element Communication Protocol (PCEP) Extension for Flow
Specification", RFC 9168, DOI 10.17487/RFC9168, January
2022, <https://www.rfc-editor.org/info/rfc9168>.
12.2. Informative References
[I-D.gont-numeric-ids-sec-considerations]
Gont, F. and I. Arce, "Security Considerations for
Transient Numeric Identifiers Employed in Network
Protocols", Work in Progress, Internet-Draft, draft-gont-
numeric-ids-sec-considerations-11, 27 January 2023,
<https://datatracker.ietf.org/doc/html/draft-gont-numeric-
ids-sec-considerations-11>.
[I-D.ietf-pce-pcep-l2-flowspec]
Dhody, D., Farrel, A., and Z. Li, "PCEP Extension for
Layer 2 (L2) Flow Specification", Work in Progress,
Internet-Draft, draft-ietf-pce-pcep-l2-flowspec-09, 30
September 2025, <https://datatracker.ietf.org/doc/html/
draft-ietf-pce-pcep-l2-flowspec-09>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC9117] Uttaro, J., Alcaide, J., Filsfils, C., Smith, D., and P.
Mohapatra, "Revised Validation Procedure for BGP Flow
Specifications", RFC 9117, DOI 10.17487/RFC9117, August
2021, <https://www.rfc-editor.org/info/rfc9117>.
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[RFC9826] Dhody, D., Ed., Beeram, V., Hardwick, J., and J. Tantsura,
"A YANG Data Model for the Path Computation Element
Communication Protocol (PCEP)", RFC 9826,
DOI 10.17487/RFC9826, September 2025,
<https://www.rfc-editor.org/info/rfc9826>.
Author's Address
Yao Liu
ZTE Corporation
China
Email: liu.yao71@zte.com.cn
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