Interdomain Routing Working Group X. Geng
Internet-Draft M. Chen
Intended status: Standards Track Huawei
Expires: September 6, 2018 Z. Li
China Mobile
March 05, 2018
IGP-TE Extensions for DetNet Information Distribution
draft-geng-detnet-info-distribution-02
Abstract
There are requirements in diverse industries to establish multi-hop
paths for characterized flows with bounded end-to-end latency and
extremely low packet loss rate. Deterministic Networking (DetNet)
can provide service satisfying the requirements.
This document describes extensions to IGP-TE, including OSPF-TE and
ISIS-TE to distribute information of DetNet, which can be used for
DetNet path computation/selection.
This document only covers the mechanisms by which DetNet information
is distributed. The mechanisms for measuring, calculating or
configuring DetNet capabilities, resources and other relevant
parameters are out of the scope.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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."
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This Internet-Draft will expire on September 6, 2018.
Copyright Notice
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. DetNet Extensions to OSPF TE . . . . . . . . . . . . . . . . 4
3.1. Congestion Protection Method sub-TLV . . . . . . . . . . 4
3.2. Maximum DetNet Reservable Bandwidth sub-TLV . . . . . . . 5
3.3. Available DetNet Bandwidth sub-TLV . . . . . . . . . . . 6
3.4. Min/Max Queuing Delay sub-TLV . . . . . . . . . . . . . . 6
4. DetNet Extensions to ISIS TE . . . . . . . . . . . . . . . . 7
4.1. Congestion Protection Method . . . . . . . . . . . . . . 7
4.2. Maximum DetNet Reservable Bandwidth . . . . . . . . . . . 8
4.3. Available DetNet Bandwidth . . . . . . . . . . . . . . . 9
4.4. Min/Max Queuing Delay . . . . . . . . . . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
5.1. Sub-TLVs for Link TLV . . . . . . . . . . . . . . . . . . 10
5.2. Sub-TLVs for TLVs 22, 23, 141, 222, and 223 . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 11
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
8.1. Normative References . . . . . . . . . . . . . . . . . . 11
8.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction
There are many use cases from diverse industries which have the need
in common for deterministic service, for example: audio video
production, industrial process control and mobile access networks.
The requirements can be summarized as:
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Deterministic minimum and maximum end-to-end latency from source
to destination
Extremely low packet loss rate
Deterministic Networking (DetNet) can satisfy the requirements by the
following techniques:
o Congestion Protection by reserving data plane resources for DetNet
flows in intermediate nodes along the path
o Explicit Route that do not rapidly change with the network
topology
o Seamless Redundant which can distribute DetNet flow packets over
multi paths to ensure delivery of each packet spite of the loss of
a path
To make the above techniques work, it's necessary to know the
capabilities (e.g., DetNet capable or not, which congestion
protection algorithms are supported, etc.), resources (e.g, dedicated
bandwidth for DetNet, buffers, etc.), performance (e.g.,
device/queue/link delay etc.) and other relevant information of each
DetNet capable node. Then, a DetNet path computation element (e.g.,
PCE or ingress of a DetNet flow) can use these information to compute
a path that satisfies the requirement of a specific DetNet flow.
Specifically, according to the requirements stated in DetNet
architecture, the information should include:
o Whether a node is DetNet capable
o Congestion protection methods supported by a DetNet capable node;
o Dedicated bandwidth for DetNet flows;
o Device and link delay;
Some of information (e.g., Link delay/loss ) can be distributed and
collected through the Traffic Engineering (TE) metric extensions
[RFC7471], [RFC7810].
This document defines extensions to OSPF and ISIS to distribute the
above DetNet information that can not distributed by the existing
protocols.
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2. Terminology
All the DetNet related terminologies used in this document conform to
the DetNet architecture [I-D.ietf-detnet-architecture].
3. DetNet Extensions to OSPF TE
This document defines new OSPF TE sub-TLVs for Link TLV to distribute
the DetNet required information as stated in Section 1. These sub-
TLVs includes:
______________________________________________________________
| Type | Length | Value |
--------------------------------------------------------------
| TBD1 | 4 | Congestion Control Method |
| TBD2 | 4 | Max DetNet Reservable Bandwidth |
| TBD3 | 4 | Available DetNet Bandwidth |
| TBD4 | 8 | Min/Max Queuing Delay |
|________|_______________|___________________________________|
3.1. Congestion Protection Method sub-TLV
This Congestion Protection (CP) Method sub-TLV is used to advertise
the DetNet flow congestion protection methods used in transit nodes.
It may be required by some DetNet flows that all the transit nodes
along the path SHOULD use the same congestion protection method.
Some typical congestion protection methods are listed as below:
Time Aware Shaping [IIEEE802.1Qbv]
Credit Based Shaper [IEEE802.1Q-2014]
Cyclic Queuing and Forwarding [IEEE802.1Qch]
Asynchronous Traffic Shaping [IEEE802.1Qcr]
The format of this sub-TLV is shown in the following diagram:
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 (TBD1) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | CP Methods |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 2 octets in length, and the value is TBD1.
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The Length field is 2 octets in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
This Congestion Control Method field presents the congestion
protection method used in the transit node.
Five congestion protection methods are introduced in this document:
_______________________________________________________________
| Value | Congestion Control Mechanisms |
---------------------------------------------------------------
| 0 | Reserved |
| 1 | Time Aware Shaper |
| 2 | Credit Based Shaper |
| 3 | Time Aware Shaper and Credit Based Shaper |
| 4 | Cyclic Queuing and Forwarding |
| 5 | Asynchronous Traffic Shaping |
| 6-254 | Unassigned |
| 255 | Reserved |
|___________|_________________________________________________|
3.2. Maximum DetNet Reservable Bandwidth sub-TLV
This sub-TLV specifies the maximum amount of bandwidth that is
reserved for DetNet on this link. Note that this value SHOULD be
smaller than the value of Maximum Reservable Bandwidth sub-TLV
[RFC3630]. The value normally depends on the Congestion Protection
Method and is user-configurable. In some particular Congestion
Protection Method (e.g. Credit Based shaper in AVB), this value will
affect the calculation of maximum queuing delay of the DetNet flow.
The units are bytes per second.
The format of this sub-TLV is shown in the following diagram:
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(TBD2) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Maximum DetNet Reservable Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 2 octets in length, and the value is TBD2.
The Length field is 2 octets in length and its value is 4.
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The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
This Maximum DetNet Reservable Bandwidth presents the maximum
bandwidth that may be reserved for DetNet. The units are bytes per
second.
3.3. Available DetNet Bandwidth sub-TLV
This sub-TLV specifies the available bandwidth that can be reserved
for DetNet flow on this link for now. Considering that there is no
generally accepted DetNet traffic classification, this value contains
all the available DetNet Bandwidth from different DetNet traffic
classes (if there is any), which differs from the Unreserved
Bandwidth defined in [RFC3630].
The format of this sub-TLV is shown in the following diagram:
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)TBD3 | (Length)4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Available DetNet Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 2 octets in length, and the value is TBD3.
The Length field is 2 octets in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
This Available DetNet Bandwidth field presents the available
bandwidth for DetNet in this link. The units are bytes per second.
3.4. Min/Max Queuing Delay sub-TLV
[Editor Notes: more consideration and inputs are needed for these
queue delays]
This sub-TLV advertises the minimum and maximum queuing delay values
of specific DetNet flow in the link. Max/Min Unidirectional Link
Delay Sub-TLV [RFC7471] excludes the queuing delay because of its
instability. With the techniques used in DetNet, the queuing delay
can be limited to a reasonable range, which means that the queuing
delay bound is stable enough to be defined as a sub-TLV and
advertised over the network.
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The format of this sub-TLV is shown in the following diagram:
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)TBD4 | (Length)8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Minimum DetNet Queuing Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Maximum DetNet Queuing Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 2 octets in length, and the value is TBD4.
The Length field is 2 octets in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
Minimum DetNet Queuing Delay is 24-bit field carrying minimum queuing
delay value (in microseconds) encoded as an integer value.
Implementations may also add this to the value of Min Delay
Unidirectional Link Delay Sub-TLV [RFC7471] in order to advertise the
minimum delay of this link. Min Queuing Delay can be the same with
the Max Queuing Delay.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
Maximum DetNet Queuing Delay is 24-bit field carrying the maximum
queuing delay value (in microseconds) encoded as an integer value.
Implementations may also add this to the value of Max Delay
Unidirectional Link Delay Sub-TLV [RFC7471]to order to advertise the
maximum delay of this link.
4. DetNet Extensions to ISIS TE
This document defines new IS-IS TE sub-TLVs that can be announced in
the TLVs 22, 23, 141, 222, and 223 in order to distribute DetNet
information. The sub-TLV extensions below build on the ones provided
in [RFC5305], [RFC5316]and [RFC7310].
4.1. Congestion Protection Method
This Congestion Protection (CP) Method sub-TLV is used to advertise
the DetNet flow congestion protection methods used in transit nodes.
The reader can know more about this sub-TLV referring to section 3.1.
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The format of this sub-TLV is shown in the following diagram:
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(TBD5) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Congestion Control Method |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 1 octet in length, and the value is TBD5.
The Length field is 1 octet in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
This Congestion Control Method field presents the congestion
protection method used in the transit node.
Five congestion protection methods are introduced in this document:
4.2. Maximum DetNet Reservable Bandwidth
This sub-TLV specifies the maximum amount of bandwidth that is
reserved for DetNet on this link. Note that this value SHOULD be
smaller than the value of Maximum Reservable Link Bandwidth
[RFC5305]. The reader can know more about this sub-TLV referring to
section 3.2.
The format of this sub-TLV is shown in the following diagram:
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(TBD6) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Maximum DetNet Reservable Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 1 octet in length, and the value is TBD6.
The Length field is 1 octet in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
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This Maximum DetNet Reservable Bandwidth presents the maximum
bandwidth that may be reserved for DetNet. The units are bytes per
second.
4.3. Available DetNet Bandwidth
This sub-TLV specifies the available bandwidth that can be reserved
for DetNet flow on this link for now. It is different from the
Unreserved Bandwidth sub-TLV defined in [RFC5305] referring to
section 3.3.
The format of this sub-TLV is shown in the following diagram:
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(TBD7) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Available DetNet Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 1 octet in length, and the value is TBD7.
The Length field is 1 octet in length and its value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
This Available DetNet Bandwidth field presents the available
bandwidth for DetNet in this link. The units are bytes per second.
4.4. Min/Max Queuing Delay
The reader can know more about this sub-TLV referring to section 3.4.
The format of this sub-TLV is shown in the following diagram:
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(TBD8) | Length(4) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Minimum DetNet Queuing Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Maximum DetNet Queuing Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Type field is 1 octet in length, and the value is TBD4.
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The Length field is 1 octet in length and it's value is 4.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
Minimum DetNet Queuing Delay is 24-bit field carrying minimum queuing
delay value (in microseconds) encoded as an integer value.
Implementations may also add this to the value of Min Unidirectional
Link Delay [RFC7810] in order to advertise the minimum delay of this
link. Min Queuing Delay can be the same with the Max Queuing Delay.
The RESERVED field is reserved for future use. It MUST be set to 0
when sent and MUST be ignored when received.
Maximum DetNet Queuing Delay is 24-bit field carrying the maximum
queuing delay value (in microseconds) encoded as an integer value.
Implementations may also add this to the value of Max Delay
Unidirectional Link Delay Sub-TLV [RFC7810] to order to advertise the
maximum delay of this link.
5. IANA Considerations
5.1. Sub-TLVs for Link TLV
IANA is requested to register the OSPF sub-TLVs defined in this
document in the sub-TLVs for Link TLV registry.
Type Description
---- ------------------------------
TBD1 Congestion Protection Method
TBD2 Maximum DetNet Reservable Bandwidth
TBD3 Available DetNet Bandwidth
TBD4 Min/Max Queuing Delay
5.2. Sub-TLVs for TLVs 22, 23, 141, 222, and 223
IANA is requested to register the ISIS sub-TLVs defined in this
document in the Sub-TLVs for TLVs 22, 23, 141, 222, and 223 registry.
Type Description
---- ------------------------------
TBD5 Congestion Protection Method
TBD6 Maximum DetNet Reservable Bandwidth
TBD7 Available DetNet Bandwidth
TBD8 Min/Max Queuing Delay
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6. Security Considerations
This document does not introduce security issues beyond those
discussed in [RFC7471] and [RFC7810].
7. Acknowledgements
8. References
8.1. Normative References
[I-D.ietf-detnet-architecture]
Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", draft-ietf-
detnet-architecture-04 (work in progress), October 2017.
[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>.
[RFC7471] Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
Previdi, "OSPF Traffic Engineering (TE) Metric
Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
<https://www.rfc-editor.org/info/rfc7471>.
[RFC7810] Previdi, S., Ed., Giacalone, S., Ward, D., Drake, J., and
Q. Wu, "IS-IS Traffic Engineering (TE) Metric Extensions",
RFC 7810, DOI 10.17487/RFC7810, May 2016,
<https://www.rfc-editor.org/info/rfc7810>.
8.2. Informative References
[IEEE802.1Q-2014]
"MAC Bridges and VLANs (IEEE 802.1Q-2014)", 2014.
[IEEE802.1Qch]
"Cyclic Queuing and Forwarding", 2016.
[IEEE802.1Qcr]
"Asynchronous Traffic Shaping", 2016.
[IIEEE802.1Qbv]
"Enhancements for Scheduled Traffic", 2016.
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[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630,
DOI 10.17487/RFC3630, September 2003,
<https://www.rfc-editor.org/info/rfc3630>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC5316] Chen, M., Zhang, R., and X. Duan, "ISIS Extensions in
Support of Inter-Autonomous System (AS) MPLS and GMPLS
Traffic Engineering", RFC 5316, DOI 10.17487/RFC5316,
December 2008, <https://www.rfc-editor.org/info/rfc5316>.
[RFC7310] Lindsay, J. and H. Foerster, "RTP Payload Format for
Standard apt-X and Enhanced apt-X Codecs", RFC 7310,
DOI 10.17487/RFC7310, July 2014,
<https://www.rfc-editor.org/info/rfc7310>.
Authors' Addresses
Xuesong Geng
Huawei
Email: gengxuesong@huawei.com
Mach(Guoyi) Chen
Huawei
Email: mach.chen@huawei.com
Zhenqiang
China Mobile
Email: lizhenqiang@chinamobile.com
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