Internet DRAFT - draft-ietf-rift-kv-registry
draft-ietf-rift-kv-registry
RIFT J. Head, Ed.
Internet-Draft T. Przygienda
Intended status: Standards Track Juniper Networks
Expires: 22 April 2024 20 October 2023
RIFT Key/Value Structure and Registry
draft-ietf-rift-kv-registry-07
Abstract
The RIFT (Routing in Fat-Trees) protocol allows for key/value pairs
to be advertised within Key-Value Topology Information Elements (KV-
TIEs). The data contained within these KV-TIEs can be used for any
imaginable purpose. This document defines the various Key-Types
(i.e. Well-Known, OUI, and Experimental) and a method to structure
corresponding values.
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 asdescribed in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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 22 April 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
Head & Przygienda Expires 22 April 2024 [Page 1]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
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 . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Key Structure . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Experimental Key-Type . . . . . . . . . . . . . . . . . . 3
2.2. Well-Known Key-Type . . . . . . . . . . . . . . . . . . . 4
2.3. OUI Key-Type . . . . . . . . . . . . . . . . . . . . . . 4
3. Design Considerations . . . . . . . . . . . . . . . . . . . . 5
3.1. Tie-Breaking Considerations . . . . . . . . . . . . . . . 5
3.1.1. Southbound Key-Value TIE Tie-Breaking Key/Value
Pair . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. Key Target . . . . . . . . . . . . . . . . . . . . . . . 6
3.2.1. Key Target Processing . . . . . . . . . . . . . . . . 7
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
4.1. RIFT Key-Types . . . . . . . . . . . . . . . . . . . . . 8
4.1.1. RIFT Key-Types Requested Entries . . . . . . . . . . 8
4.2. RIFT Well-Known Key-Types . . . . . . . . . . . . . . . . 9
4.2.1. RIFT Well-Known Key-Types Requested Entries . . . . . 9
4.3. Expert Review Guidance . . . . . . . . . . . . . . . . . 10
5. Security Considerations . . . . . . . . . . . . . . . . . . . 10
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
7. Normative References . . . . . . . . . . . . . . . . . . . . 11
8. Informative References . . . . . . . . . . . . . . . . . . . 11
Appendix A. Thrift Models . . . . . . . . . . . . . . . . . . . 11
A.1. southbound_kv.thrift . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction
The Routing in Fat-Trees RIFT [RIFT] protocol allows for key/value
pairs to be advertised within Key-Value Topology Information Elements
(KV-TIEs). There are no restrictions placed on the type of data that
is contained in KV-TIEs nor what the data is used for.
For example, it might be beneficial to advertise overlay protocol
state from leaf nodes to the Top-of-Fabric (ToF) nodes. This would
make it possible to view critical state of a fabric-wide service from
a single ToF node rather than retrieving and reconciling the same
state from multiple leaf nodes.
Head & Przygienda Expires 22 April 2024 [Page 2]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
2. Key Structure
This section describes the generic Key structure and semantics,
Figure 1 further illustrates these components.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Key-Type | Key Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Values (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Generic Key-Value Structure
*where:*
*Key-Type:*
A 1-byte value that identifies the Key-Type. It MUST be a
reserved value from the RIFT Key-Type Registry that is defined
later in this document.
The range of valid values is 1 - 255 (2^8-1).
0 is an illegal value and MUST NOT be allocated to or used by
any implementation. It MUST be ignored on receipt.
*Key Identifier:*
A 3-byte value that identifies the specific key and describes
the structure of the contained values.
The range of valid values is 1 - 16777215 (2^24-1).
0 is an illegal value and MUST NOT be allocated to or used by
any implementation. It MUST be ignored on receipt.
*Values:*
A variable length value that contains data associated with the
Key Identifier. It SHOULD contain 1 or more elements. Whether
the collection of elements allows duplicates and/or is ordered
is governed by the particular Key Identifier's specification.
2.1. Experimental Key-Type
This section reserves a value in the RIFT Key-Type Registry to
indicate an Experimental Key-Type.
Head & Przygienda Expires 22 April 2024 [Page 3]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
As shown in Figure 2, the Key-Type will be used to identify the Key-
Type as Experimental. The Key Identifier will be used to identify
the specific key and describe the structure of the contained values.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 1 | Experimental Key Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Experimental Values (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Experimental Key-Type
2.2. Well-Known Key-Type
This section reserves a value in the RIFT Key-Type Registry to
indicate Well-Known Key-Types that all implementations SHOULD
support.
As shown in Figure 3, the Key-Type will be used to identify the Key-
Type as Well-Known. The Key Identifier will be used to identify the
specific key and describe the structure of the contained values.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 2 | Well-Known Key Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Well-Known Values (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Well-Known Key-Type
2.3. OUI Key-Type
This section reserves a value in the RIFT Key-Type Registry to
indicate an OUI (vendor-specific) Key-Type that any implementation
MAY support.
As shown in Figure 4, the Key-Type will be used to identify the Key-
Type as OUI. The Key Identifier MUST use the implementing
organization's reserved OUI space to indicate the key and value
structure.
Head & Przygienda Expires 22 April 2024 [Page 4]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 3 | OUI Key Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Vendor Specific Values (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: OUI Key-Type
3. Design Considerations
While no restrictions are placed on Key-Value data or what it is used
for, it is RECOMMENDED that a serialized Thrift [THRIFT] model be
used for simpler interoperability. [RIFT-AUTO-EVPN] is an example of
this type of implementation.
Key-Value elements SHOULD NOT be used to carry topology information
used by RIFT itself to perform distributed computations.
3.1. Tie-Breaking Considerations
In cases where KV-TIEs are flooded from north to south, policies
SHOULD be implemented in order to avoid network-wide flooding.
For networks with more than one ToF node, it is RECOMMENDED that
those ToF nodes contain identical KV-TIE information when being
distributed from north to south. RIFT [RIFT] requires that only one
KV-TIE is selected when identical keys are received from multiple
northbound neighbors. If this is not considered then the tie-
breaking rules may cause a node to select a suboptimal KV-TIE.
Consider a case where failure conditions cause the ToF nodes to
become split-brained. While the Key-Type and Key Identifier will be
identical, the value(s) contained within may differ. The node(s)
receiving these differing KV-TIEs will select the one from the ToF
node with the highest System ID, potentially leading to unintended
effects.
3.1.1. Southbound Key-Value TIE Tie-Breaking Key/Value Pair
This Key/Value pair contains information that allows for verification
of proper tie-breaking for the Southbound Key store.
Head & Przygienda Expires 22 April 2024 [Page 5]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Well-Known | Southbound Tie-Break (Global) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| (System ID, |
| Level), |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Southbound Tie-Break (Global) Key/Value Pair
*where:*
*System ID:*
A REQUIRED value indicating the node's unique System ID.
*Level:*
A RECOMMENDED value indicating the node's level.
3.2. Key Target
The Key Target is an optional value that identifies group(s) of
node(s) that are intended to receive a given Key-Value TIE. Key
Targets are 64-bits in length with a valid range of 0 -
18446744073709551615 (2^64-1), this will reduce the chances that Key
Target values collide.
A value of all 0s represent that every node is intended to receive
this Key-Value TIE and MUST NOT be used for any other reason.
A value of all 1s represent that all leaf nodes are intended to
receive this Key-Value TIE and MUST NOT be used for any other reason.
Any other value MUST be derived from the following normative
algorithm.
Head & Przygienda Expires 22 April 2024 [Page 6]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
/// random seeds used in algorithms to increase entropy
pub const RANDOMSEEDS: [UnsignedSystemID; 3] = [
67438371571u64,
37087353685,
88675895388,
];
/// given a system ID delivers the bits set by the according Bloom Filter in the southbound
/// key value target.
///
/// @note: This is standardized and cannot be changed between releases!
pub (crate) fn target2bits(target: UnsignedSystemID) -> KeyValueTargetType {
(0 as usize .. 3)
.map(|s| {
let rot = (target ^ RANDOMSEEDS[s]).rotate_left(s as _);
rot.to_ne_bytes().iter().fold(0, |v: u8, nv| v.rotate_right(4) ^ *nv) % 64
})
.fold(0, |v, nv| v | v | (1 << nv))
}
Figure 6: Key Target Standard Algorithm
3.2.1. Key Target Processing
Nodes that support the processing of Key Targets MUST only do so on
KV-TIEs in the southbound direction. Key Targets MUST NOT be present
on KV-TIEs in the northbound direction and are otherwise ignored and
logged.
Nodes that do not support the processing of Key Targets MUST continue
to send KV-TIEs to all nodes in the appropriate direction.
Additionally, Key Targets MUST be preserved when KV-TIEs are re-
originated in the southbound direction.
3.2.1.1. Purging/Rollover
There are several reasons a node may select a different KV-TIE. For
example, the KV-TIE is considered newer due to the sequence number
incrementing, there was a change in the original tie-breaking result
between multiple KV-TIEs, or a loss of northbound connectivity to the
node that advertised the previously selected KV-TIE.
Consider a case where Leaf-1, Leaf-2, and Leaf-3 are members of a
group of nodes represented by Key Target KT1. If Leaf-2 is removed
from that group and a newer instance of the KV-TIE needs to be
flooded Leaf-2 will have to maintain the older KV-TIE in the LSDB
until the lifetime expires. This could lead to suboptimal behavior
in the fabric.
Head & Przygienda Expires 22 April 2024 [Page 7]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
If the new KV-TIE being flooded does not include the previous Key
Target value, then implementations SHOULD flood the newer instance of
the KV-TIE with a very short lifetime to nodes that belonged to the
previous Key Target but not the new Key Target. This logic only
applies to KV-TIEs being flooded in the southbound direction.
4. IANA Considerations
Per [RFC8126], IANA is requested to create two new registries under
the top-level "RIFT" category:
* RIFT Key-Types
* RIFT Well-Known Key-Types
The following sections detail each registry's individual requirements
and suggested values.
Experts reviewing requests for new values to either registry MUST
consider the items in the Expert Review Guidance (Section 4.3)
section.
4.1. RIFT Key-Types
This section requests that IANA create and help govern the following
registry:
*Registry Name:*
RIFT Key-Types
*Registration Procedures:*
Expert Review
*Description:*
Key-Type registry for the RIFT protocol.
*Reference:*
This document.
4.1.1. RIFT Key-Types Requested Entries
This section requests that IANA register the following suggested
values to the "RIFT Key-Types" registry.
Head & Przygienda Expires 22 April 2024 [Page 8]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
+=======+==============+=============================+===========+
| Value | Key-Type | Description | Status/ |
| | | | Reference |
+=======+==============+=============================+===========+
| 0 | Illegal | Not allowed. | This |
| | | | document |
+-------+--------------+-----------------------------+-----------+
| 1 | Experimental | Indicates that the Key-Type | This |
| | | is Experimental. | document. |
+-------+--------------+-----------------------------+-----------+
| 2 | Well-Known | Indicates that the Key-Type | This |
| | | is Well-Known. | document. |
+-------+--------------+-----------------------------+-----------+
| 3 | OUI | Indicates that the Key-Type | This |
| | | is OUI (vendor specific). | document. |
+-------+--------------+-----------------------------+-----------+
Table 1
4.2. RIFT Well-Known Key-Types
This section requests that IANA create and help govern the following
registry:
*Registry Name:*
RIFT Well-Known Key-Types
*Registration Procedures:*
Expert Review
*Description:*
Well-Known Key-Types registry for the RIFT protocol.
*Reference:*
This document.
4.2.1. RIFT Well-Known Key-Types Requested Entries
This section requests that IANA register the following suggested
values to the "RIFT Well-Known Key-Types" Registry.
Head & Przygienda Expires 22 April 2024 [Page 9]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
+=======+================+==============================+===========+
| Value | Key-Identifier | Description | Status/ |
| | | | Reference |
+=======+================+==============================+===========+
| 0 | Illegal | Not allowed. | This |
| | | | document. |
+-------+----------------+------------------------------+-----------+
| 1 | MAC/IP Binding | To be defined. | To be |
| | | | defined. |
+-------+----------------+------------------------------+-----------+
| 2 | FAM Security | To be defined. | To be |
| | Roll-Over Key | | defined. |
+-------+----------------+------------------------------+-----------+
| 127 | Southbound | Used for Southbound | This |
| | Tie-Break Key | Keystore tie- | document. |
| | | breaking purposes. | |
+-------+----------------+------------------------------+-----------+
Table 2
4.3. Expert Review Guidance
Experts reviewing requests for values from the "RIFT Key-Types"
registry or the "RIFT Well-Known Key-Types" registry are responsible
for the following:
1. Determining the existence of a specification that clearly defines
the purpose supporting the request and MUST contain all required
fields for given registry.
The document MUST also be permenent and publically available.
2. Ensuring that any requests are made available to the RIFT working
group for review should the work originate from outside of the
RIFT Working Group.
3. Ensuring that any work produce outside of the IETF does not
conflict with any work that is already published or actively
pursuing being published.
5. Security Considerations
This document introduces no new security concerns to RIFT or other
specifications referenced in this document given that the Key-Value
TIEs are already extensively secured by the RIFT [RIFT] protocol
specification itself.
Head & Przygienda Expires 22 April 2024 [Page 10]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
6. Acknowledgements
To be provided.
7. Normative References
[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>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", June
2017, <https://www.rfc-editor.org/info/rfc8126>.
[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>.
[RIFT] Przygienda, T., Sharma, A., Thubert, P., Rijsman, B.,
Afanasiev, D., and J. Head, "RIFT: Routing in Fat Trees",
Work in Progress draft-ietf-rift-rift-19, October 2023,
<https://www.ietf.org/archive/id/draft-ietf-rift-rift-
19.html>.
8. Informative References
[RIFT-AUTO-EVPN]
Head, J., Przygienda, T., and W. Lin, "RIFT Auto-EVPN",
Work in Progress, draft-ietf-rift-auto-evpn-03, December
2022, <https://www.ietf.org/archive/id/draft-ietf-rift-
auto-evpn-03.html>.
[THRIFT] Apache Software Foundation, "Thrift Language
Implementation and Documentation",
<https://github.com/apache/thrift/tree/0.15.0/doc>.
Appendix A. Thrift Models
This section contains the Thrift models that MAY be used to test
southbound Key-Value tie-breaking based on System ID. Per the main
RIFT [RIFT] specification, all signed values MUST be interpreted as
unsigned values.
A.1. southbound_kv.thrift
Head & Przygienda Expires 22 April 2024 [Page 11]
Internet-Draft draft-ietf-rift-kv-registry-07 October 2023
include "common.thrift"
namespace py southbound_kv
namespace rs models
const i8 GlobalSystemIdentifierKV = 127
/** simple type to test correct tie-breaking based on system ID */
struct SystemIdentifierKV {
1: required common.SystemIDType system_id,
2: optional common.LevelType level,
}
Figure 7: RIFT Common Schema for Southbound Key-Value Tie-Break
Key-Type
Authors' Addresses
Jordan Head (editor)
Juniper Networks
1137 Innovation Way
Sunnyvale, CA
United States of America
Email: jhead@juniper.net
Tony Przygienda
Juniper Networks
1137 Innovation Way
Sunnyvale, CA
United States of America
Email: prz@juniper.net
Head & Przygienda Expires 22 April 2024 [Page 12]
