Simple Two-Way Direct Loss Measurement Procedure
draft-gandhi-ippm-simple-direct-loss-06
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Rakesh Gandhi , Clarence Filsfils , Daniel Voyer , Mach Chen , Bart Janssens | ||
| Last updated | 2023-08-11 | ||
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draft-gandhi-ippm-simple-direct-loss-06
IPPM Working Group R. Gandhi, Ed.
Internet-Draft C. Filsfils
Intended status: Standards Track Cisco Systems, Inc.
Expires: 12 February 2024 D. Voyer
Bell Canada
M. Chen
Huawei
B. Janssens
Colt
11 August 2023
Simple Two-Way Direct Loss Measurement Procedure
draft-gandhi-ippm-simple-direct-loss-06
Abstract
This document defines Simple Two-Way Direct Loss Measurement (DLM)
procedure that can be used for Alternate-Marking Method for detecting
accurate data packet loss in a network. Specifically, DLM probe
packets are defined for both unauthenticated and authenticated modes
and they are efficient for hardware-based implementation.
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
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 12 February 2024.
Copyright Notice
Copyright (c) 2023 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.
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Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . 3
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4
2.3. Reference Topology . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Session-Sender Direct Loss Measurement Probe Packet . . . . . 5
5. Session-Reflector Direct Loss Measurement Probe Packet . . . 8
6. Data Loss Calculation . . . . . . . . . . . . . . . . . . . . 11
7. Optional Extensions . . . . . . . . . . . . . . . . . . . . . 11
8. Integrity Protection and Confidentiality Protection . . . . . 11
9. Operational Considerations . . . . . . . . . . . . . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 12
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
12.1. Normative References . . . . . . . . . . . . . . . . . . 12
12.2. Informative References . . . . . . . . . . . . . . . . . 13
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
Many Service Provider Service Level Agreements (SLAs) depend on the
ability to measure performance loss metric experienced by the
Customer data traffic flow. Accurate Customer data packet loss can
be measured by using a Direct Loss Measurement (DLM) procedure.
Currently there is no efficient active measurement procedure
available for accurate data packet loss detection in IP networks.
Note that an approach for conducting packet loss measurement in an IP
network is documented in [RFC7680]. This approach requires clock
synchronization between the measurement points and lacks support for
accurate data packet loss measurement.
[ITU-Y1731] defines procedures for performance loss monitoring for
Ethernet-based networks. Specifically, the Loss Measurement Message
(LMM) defined in Section 9.12 of [ITU-Y1731] can be used for accurate
frame loss measurement as described in Appendix II of that document.
The procedure is specific to the Ethernet-based networks and does not
apply to the IP networks.
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The Simple Two-Way Active Measurement Protocol (STAMP) provides
capabilities for the measurement of various performance metrics in IP
networks [RFC8762] without the use of a control channel to pre-signal
session parameters. The STAMP can be used for (synthetic or
inferred) packet loss measurement based on the Sequence Number in the
test packets, however, this method can only provide approximate
packet loss metrics.
[RFC8972] defines optional extensions for STAMP. The STAMP test
packet with the "Direct Measurement" TLV (Type 5) [RFC8972] can be
used for combined timestamps and data packet counters collection.
This method, however, has the following limitations when used for
detecting data packet loss:
* For hardware-based implementation (e.g., in an ASIC), the optional
"Direct Measurement" TLV adds unnecessary processing overhead on
the Session-Reflector as not all STAMP Session-Sender test packets
carry the "Direct Measurement" TLV and also there can be multiple
TLV Types present. This also means that the location of the
transmit counter is not at the fixed location in the STAMP test
packets.
* The STAMP "Direct Measurement" TLV does not support 64-bit
counters, counters for bytes, counters per traffic class.
* The STAMP "Direct Measurement" TLV also does not identify the
Block Number of the Direct Measurement, which is required for
Alternate-Marking Method (AMM) [RFC9341] for data packet loss
measurement.
This document defines Simple Two-Way Direct Loss Measurement (DLM)
procedure that can be used for Alternate-Marking Method [RFC9341] for
detecting accurate data packet loss in a network. Specifically, DLM
probe packets are defined for both unauthenticated and authenticated
modes and they are efficient for hardware-based implementation (e.g.,
in an ASIC).
2. Conventions Used in This Document
2.1. 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.
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2.2. Abbreviations
AMM: Alternate-Marking Method.
DLM: Direct Loss Measurement.
HMAC: Hashed Message Authentication Code.
MBZ: Must be Zero.
PM: Performance Measurement.
SHA: Secure Hash Algorithm.
SSID: Sender Session Identifier.
STAMP: Simple Two-Way Active Measurement Protocol.
TTL: Time To Live.
2.3. Reference Topology
As shown in the Reference Topology, the Session-Sender S1 initiates a
Direct Loss Measurement (DLM) probe packet over IP/UDP transport.
The Session-Reflector R1 receives the Session-Sender's DLM probe
packet and acts according to the local configuration. The Session-
Reflector R1 transmits a DLM reply probe packet to the Session-Sender
S1. The C1 is a transmit counter and C4 is a receive counter added
by node S1. The C2 is a receive counter and C3 is a transmit counter
added by node R1.
C1 C2
/ \
+-------+ DLM Probe Packet +-------+
| | - - - - - - - - - - - ->| |
| S1 |=========================| R1 |
| |<- - - - - - - - - - - - | |
+-------+ DLM Reply Probe Packet +-------+
\ /
C4 C3
Session-Sender Session-Reflector
Reference Topology
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3. Overview
For accurate data packet loss detection, the DLM probe packets are
transmitted by the Session-Sender over UDP transport, and are used to
collect the transmit and receive counters for the data traffic flow
under measurement. The DLM reply probe packets are transmitted by
the Session-Reflector to collect the transmit and receive counters
for the data traffic flow under measurement in the reverse direction.
The DLM probe packets carry user-configured destination UDP port.
The destination UDP port 862 is not used for the DLM probe packets.
The user-configured destination UDP port follows the guidelines
described in Section 4.1 of [RFC8762]. Different destination UDP
port is used for DLM probe packets than the STAMP test packets
defined in [RFC8762]. Hence, the Session-Sender and the Session-
Reflector do not require backwards compatibility and support for
STAMP.
A DLM session is identified by the 4-tuple (source and destination IP
addresses, source and destination UDP port numbers). A DLM Session-
Sender MAY generate a locally unique Sender Session Identifier
(SSID). The SSID is a two-octet, non-zero unsigned integer. The
SSID generation policy is implementation specific. An implementation
MUST NOT assign the same identifier to different DLM sessions. A
Session-Sender uses the SSID to identify a DLM session.
The DLM Session-Reflector operates in the Stateless mode.
In this document, the examples of DLM probe packets are shown with
UDP header, however, the probe packets can be encapsulated with a
different header based on the transport protocol used in the network.
4. Session-Sender Direct Loss Measurement Probe Packet
In this document, base Session-Sender DLM probe packet formats are
defined as shown in Figure 1 and Figure 2 for unauthenticated and
authenticated modes, respectively. They are stand-alone DLM probe
packet formats to carry the counters for the data traffic flow under
measurement. The DLM probe packet formats are similar to the base
STAMP test packet formats (for example the locations of the Counters
vs. STAMP Timestamps).
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T|S|BlockNumber| DSCP | SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| MBZ (28 octets) |
| |
| |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Session-Sender Direct Loss Measurement Probe Packet -
Unauthenticated Mode
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T|S|BlockNumber| DSCP | SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| MBZ (68 octets) |
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Session-Sender Direct Loss Measurement Probe Packet -
Authenticated Mode
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Fields are defined as the following:
Transmit Timestamp (32-bit): This is 32-bit nano-sec field of the
PTPv2 timestamp on transmit side. This field may carry Sequence
Number instead of PTPv2 timestamp.
Transmit Counter (64-bit): The number of packets or octets
transmitted by the Session-Sender in the DLM probe packet. The
counter is always written at the well-known fixed location in the DLM
probe packet. This is an important property for hardware-based
implementation (e.g., in an ASIC), e.g., for point-to-point links and
circuits. Counter is for the data traffic flow under measurement.
XBTS Flags (3-bit): The meanings of the Flag bits are:
X: Extended counter format indicator. Indicates the use of
extended (64-bit) counter values. Initialized to 1 upon creation
(and prior to transmission) of a DLM probe packet. Set to 0 when
the DLM probe packet is transmitted or received over an interface
that writes 32-bit counter values.
B: Octet (byte) count. When set to 1, indicates that the Counter
fields represent octet counts. The octet count applies to all
packets within the DLM scope, and the octet count of a packet
transmitted or received includes the total length of that packet
(but excludes headers, labels, or framing of the channel itself).
When set to 0, indicates that the Counter fields represent packet
counts.
T: Traffic-class-specific measurement indicator. Set to 1 when
the DLM session is scoped to data packets of a particular traffic
class (DSCP value), and 0 otherwise. When set to 1, the DSCP
field of the DLM probe packet indicates the measured traffic
class.
S: Sequence Number indicator. When set to 1, it indicates that
the Transmit Timestamp field contains Sequence Number (instead of
PTPv2 timestamp).
DSCP (6-bit): DSCP of the data traffic flow being measured when T
flag is set.
Block Number (6-bit): The Direct Loss Measurement using Alternate-
Marking Method [RFC9341] requires collecting Block Number of the
counters for the data traffic flow under measurement. To be able to
correlate the transmit and receive counters of the matching Block
Number, the Block Number of the counters carried in the DLM probe
packets.
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SSID (16-bit): DLM Sender Session Identifier.
HMAC: The use of the HMAC field is described in Section 4.4 of
[RFC8762]. HMAC uses its own key and the mechanism to distribute the
HMAC key is outside the scope of this document.
MBZ: Must be Zero. It MUST be all zeroed on the transmission and
MUST be ignored on receipt.
5. Session-Reflector Direct Loss Measurement Probe Packet
The Session-Reflector receives the DLM Session-Sender probe packet
and verifies it. If the DLM probe packet is validated, the Session-
Reflector that supports this specification prepares and transmits the
DLM reply probe packet. In this document, Session-Reflector DLM
reply probe packet formats are defined as shown in Figure 3 and
Figure 4, for unauthenticated and authenticated modes, respectively.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C3) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T|S|BlockNumber| DSCP | SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Counter (C2) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|FLAGS |SS-BlockNum| SS-DSCP | MBZ (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Ses-Sender TTL | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Session-Reflector Direct Loss Measurement Probe Packet -
Unauthenticated Mode
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C3) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T|S|BlockNumber| DSCP | SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Counter (C2) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Transmit Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|FLAGS |SS-BlockNum| SS-DSCP | MBZ (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Ses-Sender TTL | |
+-+-+-+-+-+-+-+-+ +
| MBZ (15 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Figure 4: Session-Reflector Direct Loss Measurement Probe Packet -
Authenticated Mode
Fields are defined as the following:
Transmit Timestamp (32-bit): This is 32-bit nano-sec field of the
PTPv2 timestamp on transmit side. This field may carry Sequence
Number instead of PTPv2 timestamp.
Transmit Counter (64-bit): The number of packets or octets
transmitted by the Session-Reflector in the DLM reply probe packet.
Counter is for the reverse direction data traffic flow under
measurement. The Session-Reflector writes the Transmit Counter at
the same location in the DLM reply probe packet as the Session-Sender
DLM probe packet. This is an important property for hardware-based
implementation (e.g., in an ASIC).
XBTS Flags (3-bit): The XBTS Flags for the reverse direction data
traffic flow under measurement set using the same procedure defined
for the Session-Sender DLM probe packet.
DSCP (6-bit): Set for the reverse direction data traffic flow under
measurement using the same procedure defined for the Session-Sender
DLM probe packet.
Block Number (6-bit): Set for the reverse direction data traffic flow
under measurement using the same procedure defined for the Session-
Sender DLM probe packet.
SSID: SSID is the exact copy of the SSID in the received Session-
Sender DLM probe packet.
Receive Counter (64-bit): The number of packets or octets received at
the Session-Reflector. It is written by the Session-Reflector in the
DLM reply probe packet. Counter is for the data traffic flow under
measurement.
Session-Sender Counter (64-bit): This is the exact copy of the
Transmit Counter from the received Session-Sender DLM probe packet.
Session-Sender Transmit Timestamp (32-bit): This is the exact copy of
the Transmit Timestamp from the received Session-Sender DLM probe
packet.
Session-Sender Block Number: This is the exact copy of the Block
Number from the received Session-Sender DLM probe packet.
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Session-Sender FLAGS: This is the exact copy of the XBTS Flags from
the received Session-Sender DLM probe packet.
Session-Sender DSCP: This is the exact copy of the DSCP from the
received Session-Sender DLM probe packet.
Session-Sender TTL: The Session-Sender TTL field is one octet long,
and its value is the copy of the TTL field in IPv4 (or Hop Limit in
IPv6) from the received Session-Sender DLM probe packet.
6. Data Loss Calculation
Using the Counters C1, C2, C3 and C4 as per reference topology, from
the nth and (n-1)th DLM probe packets, packet loss and byte loss for
the data traffic flow can be calculated as follows:
Transmit Loss TxL[ n-1, n] = (C1[ n] - C1[ n-1]) - (C2[ n] - C2[
n-1])
Receive Loss RxL[ n-1, n] = (C3[ n] - C3[ n-1]) - (C4[ n] - C4[ n-1])
The Total Transmit and Receive Loss are calculated as follows:
Total Transmit Loss = TxL[ 1, 2] + TxL[ 2, 3] + ...
Total Receive Loss = RxL[ 1, 2] + RxL[ 2, 3] + ...
These values are updated each time a DLM reply probe packet is
received and processed at the Session-Sender, and they represent the
Total Transmit and Total Receive Loss since the DLM session was
initiated. When computing the values TxL[n-1,n] and RxL[n-1,n], the
possibility of counter wrap must be taken into account.
When using Alternate-Marking Method, all Counters used for loss
calculation belongs to the same Block Number, as described in
Section 3.1 of [RFC9341].
7. Optional Extensions
There are currently no optional (TLV) extensions defined for the DLM
probe packets.
8. Integrity Protection and Confidentiality Protection
The integrity protection and confidentiality protection specified in
[RFC8762] also apply to the procedures defined in this document.
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9. Operational Considerations
The operational considerations specified in [RFC8762] also apply to
the procedures defined in this document.
10. Security Considerations
The DLM protocol defined in this document is intended for deployment
in a single operator network domain. As such, the Session-Sender
address and Session-Reflector address are provisioned by the operator
for the DLM session. It is assumed that the operator has verified
the integrity of the path and identity of the far-end Session-
Reflector.
If desired, attacks can be mitigated by performing basic validation
and sanity checks, at the Session-Sender, of the counter fields
(e.g., packet loss is not negative) in received reply probe packets.
The minimal state associated with these protocols also limits the
extent of measurement disruption that can be caused by a corrupt or
invalid probe packet to a single probe cycle.
The DLM protocol uses UDP port that could become a target of denial
of service (DoS) or could be used to aid on-path attacks. Thus, the
security considerations and measures to mitigate the risk of the
attack documented in Section 6 of [RFC8545] equally apply to the
STAMP extensions in this document.
The security considerations specified in [RFC8762] and [RFC8972] also
apply to the protocol defined in this document. Specifically, the
message integrity protection using HMAC, as defined in [RFC8762]
Section 4.4, also apply to the procedure described in this document.
11. IANA Considerations
This document has no IANA actions.
12. References
12.1. 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>.
[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>.
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[RFC9341] Fioccola, G., Ed., Cociglio, M., Mirsky, G., Mizrahi, T.,
and T. Zhou, "Alternate-Marking Method", RFC 9341,
DOI 10.17487/RFC9341, December 2022,
<https://www.rfc-editor.org/info/rfc9341>.
[RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
Two-Way Active Measurement Protocol", RFC 8762,
DOI 10.17487/RFC8762, March 2020,
<https://www.rfc-editor.org/info/rfc8762>.
12.2. Informative References
[RFC7680] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
Ed., "A One-Way Loss Metric for IP Performance Metrics
(IPPM)", STD 82, RFC 7680, DOI 10.17487/RFC7680, January
2016, <https://www.rfc-editor.org/info/rfc7680>.
[RFC8545] Morton, A., Ed. and G. Mirsky, Ed., "Well-Known Port
Assignments for the One-Way Active Measurement Protocol
(OWAMP) and the Two-Way Active Measurement Protocol
(TWAMP)", RFC 8545, DOI 10.17487/RFC8545, March 2019,
<https://www.rfc-editor.org/info/rfc8545>.
[RFC8972] Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A.,
and E. Ruffini, "Simple Two-Way Active Measurement
Protocol Optional Extensions", RFC 8972,
DOI 10.17487/RFC8972, January 2021,
<https://www.rfc-editor.org/info/rfc8972>.
[ITU-Y1731]
Recommendation ITU-TG.8013/Y.1731:
https://www.itu.int/rec/T-REC-G.8013-201508-I/en, "G.8013/
Y.1731 : Operations, administration and maintenance (OAM)
functions and mechanisms for Ethernet-based networks",
August 2015.
[SRV6-PM-TNSM]
Loreti, P., Mayer, A., Lungaroni, P., Lombardo, F.,
Scarpitta, C., Sidoretti, G., Bracciale, L., Ferrari, M.,
Salsano, S., Abdelsalam, A., Gandhi, R., and C. Filsfils,
IEEE Transactions on Network and Service Management,
"SRv6-PM: Performance Monitoring of SRv6 Networks with a
Cloud-Native Architecture:
https://arxiv.org/pdf/2007.08633.pdf", February 2021.
[SRV6-PM-IEEE]
Loreti, P., Mayer, A., Lungaroni, P., Salsano, S., Gandhi,
R., and C. Filsfils, IEEE International Conference on High
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Performance Switching and Routing, "Implementation of
Accurate Per-Flow Packet Loss Monitoring in Segment
Routing over IPv6 Networks:
https://arxiv.org/pdf/2004.11414.pdf", May 2020.
Acknowledgments
The authors would like to thank Greg Mirsky, Tianran Zhou, Gyan
Mishra, Zhenqiang Li, Reshad Rahman, Cheng Li, and Yali Wang for the
comments on Direct Loss Measurement. The authors would like to thank
Pierpaolo Loreti, Stefano Salsano, and the team for the Open Source
implementation of SRv6-PM Loss Monitoring and its publications in
[SRV6-PM-TNSM] and [SRV6-PM-IEEE]. The authors would like to
acknowledge the earlier work on the loss measurement using TWAMP
described in draft-xiao-ippm-twamp-ext-direct-loss.
Authors' Addresses
Rakesh Gandhi (editor)
Cisco Systems, Inc.
Canada
Email: rgandhi@cisco.com
Clarence Filsfils
Cisco Systems, Inc.
Email: cfilsfil@cisco.com
Daniel Voyer
Bell Canada
Email: daniel.voyer@bell.ca
Mach(Guoyi) Chen
Huawei
Email: mach.chen@huawei.com
Bart Janssens
Colt
Email: Bart.Janssens@colt.net
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