draft-ietf-i2rs-ephemeral-state-19.txt   draft-ietf-i2rs-ephemeral-state-20.txt 
I2RS working group J. Haas I2RS working group J. Haas
Internet-Draft Juniper Internet-Draft Juniper
Intended status: Informational S. Hares Intended status: Informational S. Hares
Expires: April 8, 2017 Huawei Expires: April 30, 2017 Huawei
October 5, 2016 October 27, 2016
I2RS Ephemeral State Requirements I2RS Ephemeral State Requirements
draft-ietf-i2rs-ephemeral-state-19.txt draft-ietf-i2rs-ephemeral-state-20.txt
Abstract Abstract
The I2RS (interface to the routing system) Architecture document The I2RS (interface to the routing system) Architecture document
(RFC7921) abstractly describes a number of requirements for ephemeral (RFC7921) abstractly describes a number of requirements for ephemeral
state (in terms of capabilities and behaviors) which any protocol state (in terms of capabilities and behaviors) which any protocol
suite attempting to meet the needs of I2RS has to provide. This suite attempting to meet the needs of I2RS has to provide. This
document describes, in detail, requirements for ephemeral state for document describes, in detail, requirements for ephemeral state for
those implementing the I2RS protocol. those implementing the I2RS protocol.
skipping to change at page 1, line 36 skipping to change at page 1, line 36
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 8, 2017. This Internet-Draft will expire on April 30, 2017.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 2, line 14 skipping to change at page 2, line 14
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Review of Requirements from I2RS architecture document . . . 3 2. Review of Requirements from I2RS architecture document . . . 3
3. Ephemeral State Requirements . . . . . . . . . . . . . . . . 4 3. Ephemeral State Requirements . . . . . . . . . . . . . . . . 4
3.1. Persistence . . . . . . . . . . . . . . . . . . . . . . . 4 3.1. Persistence . . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Constraints . . . . . . . . . . . . . . . . . . . . . . . 4 3.2. Constraints . . . . . . . . . . . . . . . . . . . . . . . 5
3.3. Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . 5 3.3. Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . 5
3.4. Ephemeral Configuration overlapping Local Configuration . 5 3.4. Ephemeral Configuration overlapping Local Configuration . 5
4. YANG Features for Ephemeral State . . . . . . . . . . . . . . 5 4. YANG Features for Ephemeral State . . . . . . . . . . . . . . 6
5. NETCONF Features for Ephemeral State . . . . . . . . . . . . 6 5. NETCONF Features for Ephemeral State . . . . . . . . . . . . 6
6. RESTCONF Features for Ephemeral State . . . . . . . . . . . . 6 6. RESTCONF Features for Ephemeral State . . . . . . . . . . . . 6
7. Requirements regarding Supporting Multi-Head Control via 7. Requirements regarding Supporting Multi-Head Control via
client Priority . . . . . . . . . . . . . . . . . . . . . . . 6 client Priority . . . . . . . . . . . . . . . . . . . . . . . 6
8. Multiple Message Transactions . . . . . . . . . . . . . . . . 8 8. Multiple Message Transactions . . . . . . . . . . . . . . . . 8
9. Pub/Sub Requirements Expanded for Ephemeral State . . . . . . 8 9. Pub/Sub Requirements Expanded for Ephemeral State . . . . . . 8
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
11. Security Considerations . . . . . . . . . . . . . . . . . . . 9 11. Security Considerations . . . . . . . . . . . . . . . . . . . 9
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
13.1. Normative References: . . . . . . . . . . . . . . . . . 9 13.1. Normative References: . . . . . . . . . . . . . . . . . 10
13.2. Informative References . . . . . . . . . . . . . . . . . 11 13.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
The Interface to the Routing System (I2RS) Working Group is chartered The Interface to the Routing System (I2RS) Working Group is chartered
with providing architecture and mechanisms to inject into and with providing architecture and mechanisms to inject into and
retrieve information from the routing system. The I2RS Architecture retrieve information from the routing system. The I2RS Architecture
document [RFC7921] abstractly documents a number of requirements for document [RFC7921] abstractly documents a number of requirements for
implementing the I2RS requirements. Section 2 reviews 10 key implementing the I2RS requirements. Section 2 reviews key
requirements related to ephemeral state. requirements related to ephemeral state. [RFC7921] defines ephemeral
state as "state which does not survive the reboot of a routing device
or the reboot of the software handling the I2RS software on a routing
device" (see section 1.1 of [RFC7921]).
The I2RS Working Group has chosen to use the YANG data modeling The I2RS Working Group has chosen to use the YANG data modeling
language [RFC6020] as the basis to implement its mechanisms. language [RFC6020] as the basis to implement its mechanisms.
Additionally, the I2RS Working group has chosen to re-use two Additionally, the I2RS Working group has chosen to re-use two
existing protocols, NETCONF [RFC6241] and its similar but lighter- existing protocols, NETCONF [RFC6241] and its similar but lighter-
weight relative RESTCONF [I-D.ietf-netconf-restconf], as the weight relative RESTCONF [I-D.ietf-netconf-restconf], as the
protocols for carrying I2RS. protocols for carrying I2RS.
What does re-use of a protocol mean? Re-use means that while YANG, What does re-use of a protocol mean? Re-use means that while YANG,
skipping to change at page 3, line 44 skipping to change at page 3, line 47
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
2. Review of Requirements from I2RS architecture document 2. Review of Requirements from I2RS architecture document
The I2RS architecture defines important high-level requirements for The I2RS architecture defines important high-level requirements for
the I2RS protocol. The following are requirements distilled from the I2RS protocol. The following are requirements distilled from
[RFC7921] that provide context for the ephemeral data state [RFC7921] that provide context for the ephemeral data state
requirements given in sections 3-8: requirements given in sections 3-8:
1. The I2RS protocol SHOULD support a high bandwidth, asynchronous 1. The I2RS protocol SHOULD support an interface asynchronous
interface, with real-time guarantees on getting data from an I2RS programmatic interface interface with properties of described in
agent by an I2RS client. section 5 of [RFC7920] (e.g. high throughput) with support for
target information streams, filtered evens, and thresholded
events (real-time events) sent by an I2RS agent to an I2RS Client
(Key points from section 1.1 of [RFC7921]).
2. I2RS agent MUST record the client identity when a node is created 2. I2RS agent MUST record the client identity when a node is created
or modified. The I2RS agent SHOULD to be able to read the client or modified. The I2RS agent SHOULD to be able to read the client
identity of a node and use the client identity's associated identity of a node and use the client identity's associated
priority to resolve conflicts. The secondary identity is useful priority to resolve conflicts. The secondary identity is useful
for traceability and may also be recorded. for traceability and may also be recorded. (Key points from
section 4 of [RFC7921].)
3. An I2RS Client identity MUST have only one priority for the 3. An I2RS Client identity MUST have only one priority for the
client's identifier. A collision on writes is considered an client's identifier. A collision on writes is considered an
error, but the priority associated with each client identifier is error, but the priority associated with each client identifier is
utilized to compare requests from two different clients in order utilized to compare requests from two different clients in order
to modify an existing node entry. Only an entry from a client to modify an existing node entry. Only an entry from a client
which is higher priority can modify an existing entry (First which is higher priority can modify an existing entry (First
entry wins). Priority only has meaning at the time of use. entry wins). Priority only has meaning at the time of use. (Key
points from section 7.8 of [RFC7921].)
4. I2RS Client's secondary identity data is read-only meta-data that 4. I2RS Client's secondary identity data is read-only meta-data that
is recorded by the I2RS agent associated with a data model's node is recorded by the I2RS agent associated with a data model's node
is written. Just like the primary client identity, the secondary is written. Just like the primary client identity, the secondary
identity SHOULD only be recorded when the data node is written. identity SHOULD only be recorded when the data node is written.
(Key points from sections 7.4 of [RFC7921].)
5. I2RS agent MAY have a lower priority I2RS client attempting to 5. I2RS agent MAY have a lower priority I2RS client attempting to
modify a higher priority client's entry in a data model. The modify a higher priority client's entry in a data model. The
filtering out of lower priority clients attempting to write or filtering out of lower priority clients attempting to write or
modify a higher priority client's entry in a data model SHOULD be modify a higher priority client's entry in a data model SHOULD be
effectively handled and not put an undue strain on the I2RS effectively handled and not put an undue strain on the I2RS
agent. agent. (See section 7.8 of [RFC7921] augmented by the resource
limitation language in section 8 [RFC7921].)
3. Ephemeral State Requirements 3. Ephemeral State Requirements
In requirements Ephemeral-REQ-01 to Ephemeral-REQ-15, Ephemeral state In requirements Ephemeral-REQ-01 to Ephemeral-REQ-15, Ephemeral state
is defined as potentially including in a data model ephemeral is defined as potentially including in a data model ephemeral
configuration and operational state which is flagged as ephemeral. configuration and operational state which is flagged as ephemeral.
3.1. Persistence 3.1. Persistence
Ephemeral-REQ-01: I2RS requires ephemeral state; i.e. state that does Ephemeral-REQ-01: I2RS requires ephemeral state; i.e. state that does
skipping to change at page 7, line 11 skipping to change at page 7, line 18
ability to have data nodes store I2RS client identity and not the ability to have data nodes store I2RS client identity and not the
effective priority of the I2RS client at the time the data node is effective priority of the I2RS client at the time the data node is
stored. stored.
o The priority MAY be dynamically changed by AAA, but the exact o The priority MAY be dynamically changed by AAA, but the exact
actions are part of the protocol definition as long as collisions actions are part of the protocol definition as long as collisions
are handled as described in Ephemeral-REQ-12, Ephemeral-REQ-13, are handled as described in Ephemeral-REQ-12, Ephemeral-REQ-13,
and Ephemeral-REQ-14. and Ephemeral-REQ-14.
Ephemeral-REQ-12: When a collision occurs as two clients are trying Ephemeral-REQ-12: When a collision occurs as two clients are trying
to write the same data node, this collision is considered an error to write the same data node, this collision is considered an error.
and priorities were created to give a deterministic result. When The I2RS priorities are used to provide a deterministic resolution to
there is a collision, and the data node is changed, a notification the conflict. When there is a collision, and the data node is
(which includes indicating data node the collision occurred on) MUST changed, a notification (which includes indicating data node the
BE sent to the original client to give the original client a chance collision occurred on) MUST BE sent to the original client to give
to deal with the issues surrounding the collision. The original the original client a chance to deal with the issues surrounding the
client may need to fix their state. collision. The original client may need to fix their state.
Explanation: RESTCONF and NETCONF updates can come in concurrently Explanation: RESTCONF and NETCONF updates can come in concurrently
from alternative sources. Therefore the collision detection and from alternative sources. Therefore the collision detection and
comparison of priority needs to occur for any type of update. comparison of priority needs to occur for any type of update.
For example, RESTCONF tracks the source of configuration change via For example, RESTCONF tracks the source of configuration change via
the entity-Tag (section 3.5.2 of [I-D.ietf-netconf-restconf]) which the entity-Tag (section 3.5.2 of [I-D.ietf-netconf-restconf]) which
the server returns to the client along with the value in GET or HEAD the server returns to the client along with the value in GET or HEAD
methods. RESTCONF requires that this resource entity-tag be updated methods. RESTCONF requires that this resource entity-tag be updated
whenever a resource or configuration resource within the resource is whenever a resource or configuration resource within the resource is
skipping to change at page 8, line 47 skipping to change at page 9, line 5
o Pub-Sub-REQ-01: The Subscription Service MUST support o Pub-Sub-REQ-01: The Subscription Service MUST support
subscriptions against ephemeral state in operational data stores, subscriptions against ephemeral state in operational data stores,
configuration data stores or both. configuration data stores or both.
o Pub-Sub-REQ-02: The Subscription Service MUST support filtering so o Pub-Sub-REQ-02: The Subscription Service MUST support filtering so
that subscribed updates under a target node might publish only that subscribed updates under a target node might publish only
ephemeral state in operational data or configuration data, or ephemeral state in operational data or configuration data, or
publish both ephemeral and operational data. publish both ephemeral and operational data.
o Pub-Sub-REQ-03: The subscription service must support o Pub-Sub-REQ-03: The subscription service MUST support
subscriptions which are ephemeral. (E.g. An ephemeral data model subscriptions which are ephemeral. (E.g. An ephemeral data model
which has ephemeral subscriptions.) which has ephemeral subscriptions.)
10. IANA Considerations 10. IANA Considerations
There are no IANA requirements for this document. There are no IANA requirements for this document.
11. Security Considerations 11. Security Considerations
The security requirements for the I2RS protocol are covered in The security requirements for the I2RS protocol are covered in
skipping to change at page 10, line 35 skipping to change at page 10, line 39
[RFC6614] Winter, S., McCauley, M., Venaas, S., and K. Wierenga, [RFC6614] Winter, S., McCauley, M., Venaas, S., and K. Wierenga,
"Transport Layer Security (TLS) Encryption for RADIUS", "Transport Layer Security (TLS) Encryption for RADIUS",
RFC 6614, DOI 10.17487/RFC6614, May 2012, RFC 6614, DOI 10.17487/RFC6614, May 2012,
<http://www.rfc-editor.org/info/rfc6614>. <http://www.rfc-editor.org/info/rfc6614>.
[RFC6733] Fajardo, V., Ed., Arkko, J., Loughney, J., and G. Zorn, [RFC6733] Fajardo, V., Ed., Arkko, J., Loughney, J., and G. Zorn,
Ed., "Diameter Base Protocol", RFC 6733, Ed., "Diameter Base Protocol", RFC 6733,
DOI 10.17487/RFC6733, October 2012, DOI 10.17487/RFC6733, October 2012,
<http://www.rfc-editor.org/info/rfc6733>. <http://www.rfc-editor.org/info/rfc6733>.
[RFC7920] Atlas, A., Ed., Nadeau, T., Ed., and D. Ward, "Problem
Statement for the Interface to the Routing System",
RFC 7920, DOI 10.17487/RFC7920, June 2016,
<http://www.rfc-editor.org/info/rfc7920>.
[RFC7921] Atlas, A., Halpern, J., Hares, S., Ward, D., and T. [RFC7921] Atlas, A., Halpern, J., Hares, S., Ward, D., and T.
Nadeau, "An Architecture for the Interface to the Routing Nadeau, "An Architecture for the Interface to the Routing
System", RFC 7921, DOI 10.17487/RFC7921, June 2016, System", RFC 7921, DOI 10.17487/RFC7921, June 2016,
<http://www.rfc-editor.org/info/rfc7921>. <http://www.rfc-editor.org/info/rfc7921>.
[RFC7922] Clarke, J., Salgueiro, G., and C. Pignataro, "Interface to [RFC7922] Clarke, J., Salgueiro, G., and C. Pignataro, "Interface to
the Routing System (I2RS) Traceability: Framework and the Routing System (I2RS) Traceability: Framework and
Information Model", RFC 7922, DOI 10.17487/RFC7922, June Information Model", RFC 7922, DOI 10.17487/RFC7922, June
2016, <http://www.rfc-editor.org/info/rfc7922>. 2016, <http://www.rfc-editor.org/info/rfc7922>.
 End of changes. 15 change blocks. 
24 lines changed or deleted 39 lines changed or added

This html diff was produced by rfcdiff 1.45. The latest version is available from http://tools.ietf.org/tools/rfcdiff/