Network Working Group Y. Wang
Internet-Draft S. Zhuang
Intended status: Standards Track Y. Gu
Expires: January 15, 2021 Huawei
July 14, 2020
BGP Extension for Advertising In-situ Flow Information Telemetry (IFIT)
Capabilities
draft-wang-idr-bgp-ifit-capabilities-00
Abstract
This document defines extensions to BGP to advertise the In-situ Flow
Information Telemetry (IFIT) capabilities. Within an IFIT
measurement domain, the capability is meant to be advertised from the
IFIT tail node to the head node to assist the head node to determine
whether a particular IFIT Option type can be enabled. This
facilitates the deployment of IFIT measurements on a per-service and
on-demand basis.
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."
This Internet-Draft will expire on January 15, 2021.
Wang, et al. Expires January 15, 2021 [Page 1]
Internet-Draft BGP for iFIT Capability July 2020
Copyright Notice
Copyright (c) 2020 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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Definitions and Acronyms . . . . . . . . . . . . . . . . . . 3
3. IFIT Capabilities . . . . . . . . . . . . . . . . . . . . . . 4
4. Option 1: Extending BGP Extended Community for IFIT
Capability . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. IPv4-Address-Specific IFIT Extended Community . . . . . . 4
4.2. IPv6-Address-Specific IFIT Extended Community . . . . . . 5
5. Option 2: Extendng BGP Next-Hop Capability for IFIT
Capability . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
7. Security Considerations . . . . . . . . . . . . . . . . . . . 7
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 7
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
10.1. Normative References . . . . . . . . . . . . . . . . . . 8
10.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction
At present, a family of on-path flow telemetry techniques referred in
[I-D.song-opsawg-ifit-framework] are emerging, including In-situ OAM
(IOAM) [I-D.ietf-ippm-ioam-data], Postcard-Based Telemetry (PBT)
[I-D.song-ippm-postcard-based-telemetry], IOAM Direct Export (DEX)
[I-D.ioamteam-ippm-ioam-direct-export], Enhanced Alternate Marking
(EAM) [I-D.zhou-ippm-enhanced-alternate-marking].
In-situ Flow Information Telemetry (IFIT) determines network
performance by measuring the packet loss and latency of service
packets transmitted in an IP network. This feature is easy to deploy
and provides an accurate assessment of network performance.
Wang, et al. Expires January 15, 2021 [Page 2]
Internet-Draft BGP for iFIT Capability July 2020
The IFIT model describes how service flows are measured to obtain
packet loss and latency. Specifically, IFIT measures the packet loss
and latency of service flows on the ingress and egress of the transit
network, and summarizes desired performance indicators. The IFIT
model is composed of three objects: target flow, transit network, and
measurement system. The transit network only bears target flows.
The target flows are not generated or terminated on the transit
network. The transit network can be a Layer 2 (L2), Layer 3 (L3), or
L2+L3 hybrid network. Each node on the transit network must be
reachable at the network layer. The measurement system consists of
the ingress (configured with IFIT and IFIT parameters) and multiple
IFIT-capable devices.
IFIT is a solution focusing on network domains. The "network domain"
consists of a set of network devices or entities within a single
administration. One network domain MAY consists of multiple IFIT
domain. The family of emerging on-path flow telemetry techniques MAY
be selectively or partially implemented in different vendors' devices
as an emerging feature for various use cases of application-aware
network operations, in addition, for some usecases, the IFIT Features
are deployed on a per-service and on-demand basis. Within the IFIT
domain, one or more IFIT-options are added into packet at the IFIT-
enabled head node that is referred to as the IFIT encapsulating node.
Then IFIT data fields MAY be updated by IFIT transit nodes that the
packet traverses. Finally, the data fields are removed at a device
that is referred to as the IFIT decapsulating node. Hence, a head
node needs to know if the IFIT decapsulating node is able to support
the IFIT capabilities.
This document defines extensions to BGP to advertise the IFIT
capabilities to a head node, then the head node can learn the IFIT
capabilities and determine whether a particular IFIT Option type can
be supported by the sending side as the decapsulating node. This
facilitates the deployment of IFIT measurements on a per-service and
on-demand basis.
2. Definitions and Acronyms
o IFIT: In-situ Flow Information Telemetry
o OAM: Operation Administration and Maintenance
o NLRI: Network Layer Reachable Information, the NLRI advertised in
the BGP UPDATE as defined in [RFC4271] and [RFC4760] .
Wang, et al. Expires January 15, 2021 [Page 3]
Internet-Draft BGP for iFIT Capability July 2020
3. IFIT Capabilities
This document defines the IFIT Capabilities formed of a 16-bit
bitmap. The following format is used:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|p|i|d|e|m| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1. IFIT Capabilities
o p-Flag: IOAM Pre-allocated Trace Option Type flag. When set, this
indicates that the router is capable of IOAM Pre-allocated Trace
[I-D.ietf-ippm-ioam-data].
o i-Flag: IOAM Incremental Trace Option Type flag. When set, this
indicates that the router is capable of IOAM Incremental Tracing
[I-D.ietf-ippm-ioam-data].
o d-Flag: IOAM DEX Option Type flag. When set, this indicates that
the router is capable of IOAM DEX
[I-D.ioamteam-ippm-ioam-direct-export].
o e-Flag: IOAM E2E Option Type flag. When set, this indicates that
the router is capable of IOAM E2E processing
[I-D.ietf-ippm-ioam-data].
o m-Flag: EAM flag. When set, this indicates that the router is
capable of processing Enhanced Alternative Marking packets
[I-D.zhou-ippm-enhanced-alternate-marking].
o Reserved: Must be set to zero upon transmission and ignored upon
receipt.
4. Option 1: Extending BGP Extended Community for IFIT Capability
4.1. IPv4-Address-Specific IFIT Extended Community
For IPv4 networks, this section defines a new type of BGP extended
community [RFC4360] called IPv4-Address-Specific IFIT Extended
Community. The IPv4-Address-Specific IFIT Extended Community can be
used by the IFIT decapsulation node to notify the IFIT Capabilities
to its parterner (as the IFIT encapsulation node). It is a
transitive extended community with type 0x01 and sub-type TBA.
The format of this extended community is shown in Figure 2.
Wang, et al. Expires January 15, 2021 [Page 4]
Internet-Draft BGP for iFIT Capability July 2020
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 (0x01) | Sub-Type (TBA)| IFIT Capabilities |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IPv4 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2. IPv4-Address-Specific IFIT Extended Community
o IFIT Capabilities: as defined in previous setion.
o Originating IPv4 Address field: A IPv4 address of the IFIT
decapsulation node.
4.2. IPv6-Address-Specific IFIT Extended Community
For IPv6 networks, this section defines a new type of BGP extended
community[RFC4360] called IPv6-Address-Specific IFIT Extended
Community. The IPv6-Address-Specific IFIT Extended Community can be
used by the IFIT decapsulation node to notify the IFIT Capabilities
to its parterner (as the IFIT encapsulation node). It is a
transitive IPv6 address specific extended community with type 0x00
and sub-type TBA.
The format of this extended community is shown in Figure 3.
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 (0x00) | Sub-Type (TBA)| IFIT Capabilities |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IPv6 Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IPv6 Address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IPv6 Address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IPv6 Address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3. IPv6-Address-Specific IFIT Extended Community
o IFIT Capabilities: as defined in previous setion.
o Originating IPv6 Address field: A IPv6 address of the IFIT
decapsulation node.
Wang, et al. Expires January 15, 2021 [Page 5]
Internet-Draft BGP for iFIT Capability July 2020
In this mode, the Originating IP Address (inclue IPv4 and IPv6) in
the extended community attribute is used as the IFIT decapsulation
node
5. Option 2: Extendng BGP Next-Hop Capability for IFIT Capability
The BGP Next-Hop Capability Attribute
[I-D.ietf-idr-next-hop-capability] is a non-transitive BGP attribute
which is modified or deleted when the next-hop is changed to reflect
the capabilities of the new next-hop. The attribute consists of a
set of Next-Hop Capabilities.
A Next-Hop Capability is a triple (Capability Code, Capability
Length, Capability Value) aka a TLV:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability Code (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability Length (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Capability Value (variable) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4. BGP Next-Hop Capability
o Capability Code: a two-octets unsigned binary integer which
indicates the type of "Next-Hop Capability" advertised and
unambiguously identifies an individual capability. This document
defines a new Next-Hop Capability, which is called IFIT Next-Hop
Capability. The Capability Code is TBD1.
o Capability Length: a two-octets unsigned binary integer which
indicates the length, in octets, of the Capability Value field. A
length of 0 indicates that no Capability Value field is present.
o Capability Value: a variable-length field. It is interpreted
according to the value of the Capability Code. For the IFIT Next-
Hop Capability, Capability Value contains IFIT Capabilities and
Originate IP Address, as shown in the following figure.
Wang, et al. Expires January 15, 2021 [Page 6]
Internet-Draft BGP for iFIT Capability July 2020
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IFIT Capabilities (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originating IP Address |
| (4 or 16 octets) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5. BGP Capability Value for IFIT
o IFIT Capabilities: as defined in previous setion.
o Originating IP Address: An IPv4 or IPv6 Address of the IFIT
decapsulation node.
A BGP speaker S that sends an UPDATE with the BGP Next-Hop Capability
Attribute MAY include the IFIT Next-Hop Capability. The inclusion of
the iFIT Next-Hop Capability with the NLRI advertised in the BGP
UPDATE indicates that the BGP Next-Hop can act as the IFIT
decapsulating node and it can process the specific iFIT encapsulation
format indicated per the capability value. This is applied for all
routes indicated in the same NRLI.
A BGP speaker receiving an IFIT Next-Hop Capability containing the
IFIT options that it can supports behaves as defined in the document
defining these iFIT options.
6. IANA Considerations
TBD
7. Security Considerations
TBD
8. Contributors
The following people made significant contributions to this document:
Wang, et al. Expires January 15, 2021 [Page 7]
Internet-Draft BGP for iFIT Capability July 2020
Weidong Li
Huawei
Email: poly.li@huawei.com
Haibo Wang
Huawei
Email: rainsword.wang@huawei.com
Tianran Zhou
Huawei
Email: zhoutianran@huawei.com
9. Acknowledgements
TBD
10. References
10.1. Normative References
[I-D.ietf-bess-srv6-services]
Dawra, G., Filsfils, C., Raszuk, R., Decraene, B., Zhuang,
S., and J. Rabadan, "SRv6 BGP based Overlay services",
draft-ietf-bess-srv6-services-03 (work in progress), July
2020.
[I-D.ietf-idr-next-hop-capability]
Decraene, B., Kompella, K., and W. Henderickx, "BGP Next-
Hop dependent capabilities", draft-ietf-idr-next-hop-
capability-05 (work in progress), June 2019.
[I-D.ietf-ippm-ioam-data]
Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
for In-situ OAM", draft-ietf-ippm-ioam-data-10 (work in
progress), July 2020.
[I-D.ioamteam-ippm-ioam-direct-export]
Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F.,
Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ
OAM Direct Exporting", draft-ioamteam-ippm-ioam-direct-
export-00 (work in progress), October 2019.
[I-D.song-ippm-postcard-based-telemetry]
Song, H., Zhou, T., Li, Z., Shin, J., and K. Lee,
"Postcard-based On-Path Flow Data Telemetry", draft-song-
ippm-postcard-based-telemetry-07 (work in progress), April
2020.
Wang, et al. Expires January 15, 2021 [Page 8]
Internet-Draft BGP for iFIT Capability July 2020
[I-D.wang-idr-bgp-ls-ifit-node-capability]
Wang, Y., Zhou, T., and R. Pang, "Extensions to BGP-LS for
Advertising In-situ Flow Information Telemetry (IFIT) Node
Capability", draft-wang-idr-bgp-ls-ifit-node-capability-03
(work in progress), March 2020.
[I-D.zhou-ippm-enhanced-alternate-marking]
Zhou, T., Fioccola, G., Lee, S., Cociglio, M., and W. Li,
"Enhanced Alternate Marking Method", draft-zhou-ippm-
enhanced-alternate-marking-05 (work in progress), July
2020.
[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>.
10.2. Informative References
[I-D.song-opsawg-ifit-framework]
Song, H., Qin, F., Chen, H., Jin, J., and J. Shin, "In-
situ Flow Information Telemetry", draft-song-opsawg-ifit-
framework-12 (work in progress), April 2020.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
February 2006, <https://www.rfc-editor.org/info/rfc4360>.
[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>.
Authors' Addresses
Yali Wang
Huawei
Beijing
China
Email: wangyali11@huawei.com
Wang, et al. Expires January 15, 2021 [Page 9]
Internet-Draft BGP for iFIT Capability July 2020
Shunwan Zhuang
Huawei
Beijing
China
Email: zhuangshunwan@huawei.com
Yunan Gu
Huawei
Beijing
China
Email: guyunan@huawei.com
Wang, et al. Expires January 15, 2021 [Page 10]