DetNet Deterministic Latency Option for IPv6
draft-xiong-detnet-6man-queuing-option-02
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
|
|
|---|---|---|---|
| Authors | Quan Xiong , Aihua Liu | ||
| Last updated | 2022-09-29 (Latest revision 2022-07-10) | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-xiong-detnet-6man-queuing-option-02
DETNET Q. Xiong
Internet-Draft A. Liu
Intended status: Standards Track ZTE Corporation
Expires: 2 April 2023 29 September 2022
DetNet Deterministic Latency Option for IPv6
draft-xiong-detnet-6man-queuing-option-02
Abstract
This document introduces new IPv6 options to identify the
Deterministic Latency related information for DetNet flows in IPv6
and SRv6 networks.
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 2 April 2023.
Copyright Notice
Copyright (c) 2022 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.
Xiong & Liu Expires 2 April 2023 [Page 1]
Internet-Draft DetNet Deterministic Latency Option for September 2022
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. The DetNet Options . . . . . . . . . . . . . . . . . . . . . 3
3.1. The Deterministic Latency information Option . . . . . . 4
3.1.1. Flag . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.2. Deterministic Latency Parameters . . . . . . . . . . 6
4. Encapsulation of DetNet Options . . . . . . . . . . . . . . . 7
4.1. IPv6 Networks . . . . . . . . . . . . . . . . . . . . . . 7
4.2. SRv6 Networks . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 8
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
7.1. New Option for IPv6 . . . . . . . . . . . . . . . . . . . 8
8. Normative References . . . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction
According to [RFC8655], Deterministic Networking (DetNet) operates at
the IP layer and delivers service which provides extremely low data
loss rates and bounded latency within a network domain. DetNet data
planes has been specified in [RFC8938]. The existing deterministic
technologies are facing large-scale number of nodes and long-distance
transmission, traffic scheduling, dynamic flows, and other
controversial issues in large-scale networks. The enhanced DetNet
Data plane is required to support a data plane method of flow
identification and packet treatment.
[I-D.liu-detnet-large-scale-requirements] has described the
enhancement requirements for DetNet data plane, it is required to
support information used by functions ensuring Deterministic Latency.
[I-D.xiong-detnet-large-scale-enhancements] has proposed the overall
framework of DetNet enhancements for large-scale deterministic
networks. The packet treatment should support new functions to
ensure deterministic latency and the identification of deterministic
latency related information.
As described in [I-D.ietf-detnet-bounded-latency], the end-to-end
bounded latency depends on the value of queuing delay bound along
with the queuing mechanisms. Multiple queuing mechanisms can be used
to guarantee the bounded latency in DetNet. And many types of
queuing mechanisms have been proposed to provide diversified
deterministic service for various applications. For example, time-
scheduling queuing mechanisms includes the Time Aware Shaping
[IIEEE802.1Qbv] and priority-scheduling includes the Credit-Based
Xiong & Liu Expires 2 April 2023 [Page 2]
Internet-Draft DetNet Deterministic Latency Option for September 2022
Shaper[IEEE802.1Q-2014] with Asynchronous Traffic
Shaping[IEEE802.1Qcr]. The cyclic-scheduling queuing mechanism has
been proposed in [IEEE802.1Qch] and improved in
[I-D.dang-queuing-with-multiple-cyclic-buffers]. The deadline-
scheduling queuing mechanism has been proposed in [I-D.stein-srtsn]
and improved in [I-D.peng-detnet-deadline-based-forwarding]. The
per-flow queuing mechanism includes Guaranteed-Service Integrated
service (IntServ) [RFC2212]. The asynchronous queuing mechanism
includes the Asynchronous Deterministic Networking (ADN) as per
[I-D.joung-detnet-asynch-detnet-framework]. The functions such as
the queuing mechanisms should be provided for enhanced DetNet to
ensure the deterministic latency. So it is required to carry
deterministic latency related information such as queuing parameters
in data plane so as to make appropriate packet forwarding and
scheduling decisions to meet the time bounds. The DetNet forwarding
nodes along the path can apply the function and the deterministic
latency related information carried in the packet to achieve the end-
to-end bounded latency.
This document introduces new IPv6 options to identify the
Deterministic Latency related information for DetNet flows in IPv6
and SRv6 networks.
2. Conventions used in this document
2.1. Terminology
The terminology is defined as [RFC8655].
2.2. 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. The DetNet Options
This document defines new IPv6 options for DetNet to signal
Deterministic Latency related information to the DetNet layers. The
format of the options follow the generic definition in section 4.2 of
[RFC8200]. The option may be placed either in an HbH or a DoH EH.
Xiong & Liu Expires 2 April 2023 [Page 3]
Internet-Draft DetNet Deterministic Latency Option for September 2022
3.1. The Deterministic Latency information Option
The DetNet Deterministic Latency Information Option helps to
discriminate the types of mechanisms and specify the related
parameters.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Opt Data Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flag | Reserved |TU | QDL | QPL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Deterministic Delay (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Deterministic Delay variation (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Deterministic Latency Parameters sub-TLV(variable) (optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Deterministic Latency Option Format
Option Type: 8-bit identifier of the type of option. Value TBD1 by
IANA; the highest-order 3 bits of the field is 001 to skip over this
option and continue processing the header if the processing IPv6 node
does not recognize the Option Type and to permit the Option Data to
be changed en route to the packet's final destination.
Opt Data Len: 8-bit unsigned integer. Length of the Option Data
field of this option, in octets. It is set to 12.
Flag(16 bits): indicates the type of Deterministic Latency function.
The flag is defined in section 3.1.1.
TU(2 bits): indicates the time units for the Deterministic Delay.
ODL(3 bits): Length of the Deterministic Delay field as an unsigned
3-bit integer. The length of Deterministic Delay variation field is
same with Deterministic Delay field.
OPL(3 bits): Length of the Deterministic Latency Parameters field as
an unsigned 3-bit integer.
Maximum Deterministic Delay (variable): indicates the Maximum queuing
delay. The value is various when the Queuing type is different.
Xiong & Liu Expires 2 April 2023 [Page 4]
Internet-Draft DetNet Deterministic Latency Option for September 2022
Maximum Deterministic Delay variation (variable): indicates the
Maximum Deterministic delay variation. The value is various when the
flag is different.
Deterministic Latency Parameters Sub-TLVs (variable): it is optional
and provides additional information for a node to forward a DetNet
flow. The Sub-TLVs has been defined in section 3.1.2.
3.1.1. Flag
The types of Deterministic Latency function should cover all the
mechanisms ensuring the Deterministic Latency such as the existing
queuing and scheduling mechanisms and other mechanisms which may be
proposed in the future.
It indicates that a type of mechanisms is used for DetNet when one
flag is set to 1 and multiple cooperating queuing mechanisms may be
implemented when more than one flag is set to 1. For example,
Credit-Based Shaper with Asynchronous Traffic Shaping can be used to
provide the guaranteed delay. This document proposed the flags to
cover the existing mechanisms and other mechanisms should be taken
into considerations in the future.
The Flags field is designed as follow:
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T|P|C|A|M|D|N| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Flag
T flag: 1 bit, if the flag is set to 1, it indicates the TAS (Time
Aware Shaping) [IIEEE802.1Qbv] queuing mechanism.
P Flag: 1 bit, if the flag is set to 1, it indicates the CBS (Credit-
Based Shaper) [IEEE802.1Q-2014] queuing mechanism.
C Flag: 1 bit, if the flag is set to 1, it indicates the CQF (Cyclic
Queuing and Forwarding) [IEEE802.1Qch] queuing mechanism.
A Flag: 1 bit, if the flag is set to 1, it indicates the ATS
(Asynchronous Traffic Shaping) [IEEE802.1Qcr] queuing mechanism.
M Flag: 1 bit, if the flag is set to 1, it indicates the Multiple
Cyclic Queuing as defined in
[I-D.dang-queuing-with-multiple-cyclic-buffers].
Xiong & Liu Expires 2 April 2023 [Page 5]
Internet-Draft DetNet Deterministic Latency Option for September 2022
D Flag: 1 bit, if the flag is set to 1, it indicates the Deadline-
based Queuing mechanisms defined in
[I-D.peng-detnet-deadline-based-forwarding] and [I-D.stein-srtsn].
N Flag: 1 bit, if the flag is set to 1, it indicates the ADN
mechanism defined in [I-D.joung-detnet-asynch-detnet-framework].
3.1.2. Deterministic Latency Parameters
The Deterministic Latency Parameters sub-TLVs is optional and it
provides Deterministic Latency additional parameters for a node to
forward a DetNet flow. The format of Sub-TLVs is based on the type
and the flag field.
When the M flag is set to 1, the Cycle Sub-TLV may be carried and
designed as follow:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cycle Profile ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cycle ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Cycle Sub-TLV
Sub-type (16bits): TBD2, indicates the type of Cycle Sub-TLV.
Length (16bits): indicated the length of Cycle Sub-TLV.
Cycle Profile ID (32bits): indicates the profile ID which the cyclic
queue applied at a node.
Cycle ID (32bits): indicates the Cycle ID for a node to forward a
DetNet flow.
When the D flag is set to 1, the Deadline Sub-TLV may be carried and
designed as follow:
Xiong & Liu Expires 2 April 2023 [Page 6]
Internet-Draft DetNet Deterministic Latency Option for September 2022
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Deadline Information(variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Deadline Sub-TLV
Sub-type (16bits): TBD3, indicates the type of Deadline Sub-TLV.
Length (16bits): indicated the length of Deadline Sub-TLV.
Deadline Information(variable): indicates the deadline information
such as deadline as defined in [I-D.stein-srtsn] or planned Deadline
and deadline Deviation as defined in [I-D.peng-6man-deadline-option].
4. Encapsulation of DetNet Options
4.1. IPv6 Networks
The DetNet Deterministic Latency information Option is intended to be
placed in an IPv6 HbH EH since it must be processed by every DetNet
forwarding node along the path. All DetNet forwarding nodes can use
the queuing information to achieve the packet forwarding and queue
scheduling.
+-----------------------------------+
| DetNet App-Flow |
| (original IP) Packet |
+-----------------------------------+
| other EHs |
+-----------------------------------+--\
| IPv6 Hop-by-Hop Ex Hdr | |
|(Deterministic Latency Info Option)| DetNet Options
| | |
+-----------------------------------+--/
| IPv6 Header |
+-----------------------------------+
| Data-Link |
+-----------------------------------+
| Physical |
+-----------------------------------+
Xiong & Liu Expires 2 April 2023 [Page 7]
Internet-Draft DetNet Deterministic Latency Option for September 2022
Figure 5: Deterministic Latency Information Option Format
4.2. SRv6 Networks
The DetNet Deterministic Latency information Option is intended to be
placed in an DOH EH before an SRH since it must be processed by the
DetNet forwarding nodes of the SRv6 segment list. The DetNet
forwarding nodes among SRv6 segment list can use the Deterministic
Latency to achieve the packet forwarding and queue scheduling.
+-----------------------------------+
| DetNet App-Flow |
| (original IP) Packet |
+-----------------------------------+
| Segment Routing Header |
+-----------------------------------+ ---\
| IPv6 Destination Ex Hdr | |
|(Deterministic Latency Info Option)| DetNet Options
| | |
+-----------------------------------+ ---/
| IPv6 Header |
+-----------------------------------+
| Data-Link |
+-----------------------------------+
| Physical |
+-----------------------------------+
Figure 6: Deterministic Latency Information Option Format
5. Security Considerations
TBA
6. Acknowledgements
The authors would like to thank Peng Liu, Bin Tan, Shaofu Peng for
their review, suggestions and comments to this document.
7. IANA Considerations
7.1. New Option for IPv6
This specification updates the "Destination Options and Hop-by-Hop
Options" under the "Internet Protocol Version 6 (IPv6) Parameters"
registry with the values below:
Xiong & Liu Expires 2 April 2023 [Page 8]
Internet-Draft DetNet Deterministic Latency Option for September 2022
+======+==========================================+=================+
| Type | Description | Reference |
+======+==========================================+=================+
| TBD1 | Deterministic Latency Information Option | [this |
| | | document] |
+------+------------------------------------------+-----------------+
Table 1
The Sub-TLVs has been proposed for Deterministic Latency Information
Option as following shown:
+==========+==================+=================+
| Sub-type | Description | Reference |
+==========+==================+=================+
| TBD2 | Cycle Sub-TLV | [this document] |
+----------+------------------+-----------------+
| TBD3 | Deadline Sub-TLV | [this document] |
+----------+------------------+-----------------+
Table 2
8. Normative References
[I-D.dang-queuing-with-multiple-cyclic-buffers]
Liu, B. and J. Dang, "A Queuing Mechanism with Multiple
Cyclic Buffers", Work in Progress, Internet-Draft, draft-
dang-queuing-with-multiple-cyclic-buffers-00, 22 February
2021, <https://www.ietf.org/archive/id/draft-dang-queuing-
with-multiple-cyclic-buffers-00.txt>.
[I-D.ietf-detnet-bounded-latency]
Finn, N., Boudec, J. L., Mohammadpour, E., Zhang, J., and
B. Varga, "DetNet Bounded Latency", Work in Progress,
Internet-Draft, draft-ietf-detnet-bounded-latency-10, 8
April 2022, <https://www.ietf.org/archive/id/draft-ietf-
detnet-bounded-latency-10.txt>.
[I-D.joung-detnet-asynch-detnet-framework]
Joung, J., Ryoo, J., Cheung, T., Li, Y., and P. Liu,
"Asynchronous Deterministic Networking Framework for
Large-Scale Networks", Work in Progress, Internet-Draft,
draft-joung-detnet-asynch-detnet-framework-00, 26 June
2022, <https://www.ietf.org/archive/id/draft-joung-detnet-
asynch-detnet-framework-00.txt>.
Xiong & Liu Expires 2 April 2023 [Page 9]
Internet-Draft DetNet Deterministic Latency Option for September 2022
[I-D.liu-detnet-large-scale-requirements]
Liu, P., Li, Y., Eckert, T., Xiong, Q., and J. Ryoo,
"Requirements for Large-Scale Deterministic Networks",
Work in Progress, Internet-Draft, draft-liu-detnet-large-
scale-requirements-02, 10 April 2022,
<https://www.ietf.org/archive/id/draft-liu-detnet-large-
scale-requirements-02.txt>.
[I-D.peng-6man-deadline-option]
Peng, S. and B. Tan, "Deadline Option", Work in Progress,
Internet-Draft, draft-peng-6man-deadline-option-00, 11
January 2022, <https://www.ietf.org/archive/id/draft-peng-
6man-deadline-option-00.txt>.
[I-D.peng-detnet-deadline-based-forwarding]
Peng, S., Tan, B., and P. Liu, "Deadline Based
Deterministic Forwarding", Work in Progress, Internet-
Draft, draft-peng-detnet-deadline-based-forwarding-01, 1
March 2022, <https://www.ietf.org/archive/id/draft-peng-
detnet-deadline-based-forwarding-01.txt>.
[I-D.stein-srtsn]
Stein, Y. (., "Segment Routed Time Sensitive Networking",
Work in Progress, Internet-Draft, draft-stein-srtsn-01, 29
August 2021, <https://www.ietf.org/archive/id/draft-stein-
srtsn-01.txt>.
[I-D.xiong-detnet-large-scale-enhancements]
Xiong, Q. and Z. Du, "DetNet Enhancements for Large-Scale
Deterministic Networks", Work in Progress, Internet-Draft,
draft-xiong-detnet-large-scale-enhancements-00, 24
February 2022, <https://www.ietf.org/archive/id/draft-
xiong-detnet-large-scale-enhancements-00.txt>.
[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>.
[RFC2212] Shenker, S., Partridge, C., and R. Guerin, "Specification
of Guaranteed Quality of Service", RFC 2212,
DOI 10.17487/RFC2212, September 1997,
<https://www.rfc-editor.org/info/rfc2212>.
[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>.
Xiong & Liu Expires 2 April 2023 [Page 10]
Internet-Draft DetNet Deterministic Latency Option for September 2022
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", RFC 8655,
DOI 10.17487/RFC8655, October 2019,
<https://www.rfc-editor.org/info/rfc8655>.
[RFC8938] Varga, B., "Deterministic Networking (DetNet) Data Plane
Framework", RFC 8938, DOI 10.17487/RFC8938, November 2020,
<https://www.rfc-editor.org/info/rfc8938>.
Authors' Addresses
Quan Xiong
ZTE Corporation
No.6 Huashi Park Rd
Wuhan
Hubei, 430223
China
Email: xiong.quan@zte.com.cn
Aihua Liu
ZTE Corporation
Shenzhen
China
Email: liu.aihua@zte.com.cn
Xiong & Liu Expires 2 April 2023 [Page 11]