Internet DRAFT - draft-tgraf-opsawg-ipfix-inband-telemetry
draft-tgraf-opsawg-ipfix-inband-telemetry
Network Working Group T. Graf
Internet-Draft Swisscom
Intended status: Standards Track B. Claise
Expires: 29 January 2023 Huawei
A. Huang Feng
INSA-Lyon
28 July 2022
Export of Forwarding Path Delay in IPFIX
draft-tgraf-opsawg-ipfix-inband-telemetry-01
Abstract
This document introduces new IP Flow Information Export (IPFIX)
information elements to expose the Inband Telemetry measured
forwarding path delay on the IOAM transit and decapsulation nodes.
Status of This Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Performance Metrics . . . . . . . . . . . . . . . . . . . . . 5
2.1. IP One-Way Delay Hybrid Type I Passive Registry
Entries . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.1. Summary . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.2. Description . . . . . . . . . . . . . . . . . . . . . 6
2.1.3. Change Controller . . . . . . . . . . . . . . . . . . 6
2.1.4. Version of Registry Format . . . . . . . . . . . . . 6
2.2. Metric Definition . . . . . . . . . . . . . . . . . . . . 6
2.2.1. Reference Definition . . . . . . . . . . . . . . . . 6
2.2.2. Fixed Parameters . . . . . . . . . . . . . . . . . . 7
2.3. Method of Measurement . . . . . . . . . . . . . . . . . . 7
2.3.1. Reference Methods . . . . . . . . . . . . . . . . . . 7
2.3.2. Packet Stream Generation . . . . . . . . . . . . . . 7
2.3.3. Traffic Filtering (Observation) Details . . . . . . . 8
2.3.4. Sampling Distribution . . . . . . . . . . . . . . . . 8
2.3.5. Runtime Parameters and Data Format . . . . . . . . . 8
2.3.6. Roles . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4. Output . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4.1. Type . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4.2. Reference Definition . . . . . . . . . . . . . . . . 9
2.4.3. Administrative Items . . . . . . . . . . . . . . . . 11
2.4.4. Comments and Remarks . . . . . . . . . . . . . . . . 12
3. IPFIX Information Elements . . . . . . . . . . . . . . . . . 12
4. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
5.1. Performance Metrics . . . . . . . . . . . . . . . . . . . 14
5.2. IPFIX Entities . . . . . . . . . . . . . . . . . . . . . 14
5.2.1. PathDelayMeanDeltaMicroseconds . . . . . . . . . . . 15
5.2.2. PathDelayMeanDeltaNanoseconds . . . . . . . . . . . . 16
5.2.3. PathDelayMinDeltaMicroseconds . . . . . . . . . . . . 16
5.2.4. PathDelayMinDeltaNanoseconds . . . . . . . . . . . . 16
5.2.5. PathDelayMaxDeltaMicroseconds . . . . . . . . . . . . 16
5.2.6. PathDelayMaxDeltaNanoseconds . . . . . . . . . . . . 16
5.2.7. PathDelaySumDeltaMicroseconds . . . . . . . . . . . . 17
5.2.8. PathDelaySumDeltaNanoseconds . . . . . . . . . . . . 17
6. Operational Considerations . . . . . . . . . . . . . . . . . 17
6.1. Time Accuracy . . . . . . . . . . . . . . . . . . . . . . 17
6.2. Mean Delay . . . . . . . . . . . . . . . . . . . . . . . 17
6.3. IOAM Packet Time Stamps . . . . . . . . . . . . . . . . . 17
7. Security Considerations . . . . . . . . . . . . . . . . . . . 17
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
9.1. Normative References . . . . . . . . . . . . . . . . . . 18
9.2. Informative References . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20
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1. Introduction
Network operators want a statistical delay view of their networks.
They want to understand where in the network, for which customer
traffic, how much and why delay is being accummlated. In order to
answer why and where, delay needs to be reported into device and
control-plane context. In order to understand which customer traffic
is affected, delay needs to be reported into customer data-plane
context. That enables network operators to quickly identify when the
control-plane updates the current path with a different next-hop and
therefore the forwarding path changes to different nodes and
interfaces, how the path delay changes for which customer traffic.
With Inband Telemetry, defined in In-situ OAM
[I-D.ietf-ippm-ioam-deployment], Path Tracing
[I-D.filsfils-spring-path-tracing] and In-situ Flow Information
Telemetry [I-D.song-opsawg-ifit-framework], the path delay between
two endpoints is measured by inserting a timestamp in the packet.
Inband Telemetry can be distinguished between two modes. Passport
mode, [RFC9197], where only the last hop in the forwarding path of
the Inband Telemetry domain exposes all the metrics, and postcard
mode, [I-D.song-ippm-postcard-based-telemetry], where the metrics are
also exposed in the transit nodes. In both modes the forwarding path
exposes performance metrics allowing to determine how much delay has
been accumulated on which hop.
This document defines eight new IPFIX Information Elements (IEs),
exposing the forwarding path delay on IOAM transit and decapsulation
nodes. Since these IPFIX IEs are performance metrics [RFC8911], they
must be registered as registered performance metrics [RFC8911] in the
"IANA Performance Metric Registry [IANA-PERF-METRIC].
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+-----------------------------+-------------------------------------+
| Performance Metric | IPFIX Entity |
+-----------------------------+-------------------------------------+
|OWDelay_HybridType1_Passive_I|PathDelayMeanDeltaMicroseconds (TBD5)|
|P_RFCTBD_Seconds_Mean (TBD1) |PathDelayMeanDeltaNanoseconds (TBD6) |
+-----------------------------+-------------------------------------+
|OWDelay_HybridType1_Passive_I|PathDelayMinDeltaMicroseconds (TBD7) |
|P_RFCTBD_Seconds_Min (TBD2) |PathDelayMinDeltaNanoseconds (TBD8) |
+-----------------------------+-------------------------------------+
|OWDelay_HybridType1_Passive_I|PathDelayMaxDeltaMicroseconds (TBD9) |
|P_RFCTBD_Seconds_Max (TBD3) |PathDelayMaxDeltaNanoseconds (TBD10) |
+-----------------------------+-------------------------------------+
|OWDelay_HybridType1_Passive_I|PathDelaySumDeltaMicroseconds (TBD11)|
|P_RFCTBD_Seconds_Sum (TBD4) |PathDelaySumDeltaNanoseconds (TBD12) |
+-----------------------------+-------------------------------------+
Table 1: Correspondance between IE and performance metric registry
The delay is measured by calculating the difference between the
timestamp imposed with Inband Telemetry in the packet at the IOAM
encapsulation node and the timestamp exported in the IPFIX flow
record from the IOAM transit and decapsulation nodes. Depending on
the IE, the lowest, highest or the sum of measured path delay is
being exported.
IOAM-Domain
.........................................
. .
. D1 .
. <------> .
. .
. D2 .
. <--------------------> .
. .
. D3 .
. <-----------------------------------> .
. .
(H1) ------ (R1) ------- (R2) ------- (R3) -------- (R4) ------ (H2)
Host 1 Encapsulation Transit Transit Decapsulation Host 2
Node Node 1 Node 2 Node
. .
. .
.........................................
Figure 1: IOAM Delay use case. Packets flow from host 1 to host 2.
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On the usecase showed in Figure 1 using IOAM to export the delay
metrics, the node R2 exports the delay D1, the node R3 exports the
delay D2 and the decapsulation node R4 exports the total delay D3
using IPFIX.
2. Performance Metrics
This section defines and describes the new performance metrics
2.1. IP One-Way Delay Hybrid Type I Passive Registry Entries
This section specifies four Registry Entries for the Hybrid Type I
Passive assessment of IP One-Way Delay.
All column entries besides the ID, Name, Description, and Output
Reference Method categories are the same; thus, this section defines
four closely related Registry Entries. As a result, IANA has
assigned corresponding URLs to each of the four Named Metrics.
2.1.1. Summary
This category includes multiple indexes to the Registry Entry: the
element ID and Metric Name.
2.1.1.1. ID (Identifier)
<insert a numeric Identifier, an integer, TBD>
2.1.1.2. Name
IANA has allocated the numeric Identifiers TBD1-4 for the four Named
Metric Entries in this section
2.1.1.3. Name
TBD1: OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Mean
TBD2: OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Min
TBD3: OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Max
TBD4: OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Sum
2.1.1.4. URI
URL: https://www.iana.org/assignments/performance-metrics/
OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Mean
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URL: https://www.iana.org/assignments/performance-metrics/
OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Min
URL: https://www.iana.org/assignments/performance-metrics/
OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Max
URL: https://www.iana.org/assignments/performance-metrics/
OWDelay_HybridType1_Passive_IP_RFCTBD_Seconds_Sum
2.1.2. Description
This metric assesses the one-way delay of IP packets constituting a
single connection between two hosts. We consider the measurement of
one-way delay based on a single Observation Point (OP) [RFC7011]
somewhere in the network. The output is the one-way delay for all
successfully forwarded packets expressed as the <statistic> of their
conditional delay distribution, where <statistic> is one of:
* Mean
* Min
* Max
* Sum
2.1.3. Change Controller
IETF
2.1.4. Version of Registry Format
1.0
2.2. Metric Definition
This category includes columns to prompt the entry of all necessary
details related to the metric definition, including the immutable
document reference and values of input factors, called "Fixed
Parameters".
2.2.1. Reference Definition
Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton, Ed., "A One-
Way Delay Metric for IP Performance Metrics (IPPM)", STD 81, RFC
7679, DOI 10.17487/RFC7679, January 2016, <https://www.rfc-
editor.org/info/rfc7679>. [RFC7679]
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Morton, A. and E. Stephan, "Spatial Composition of Metrics", RFC
6049, DOI 10.17487/RFC6049, January 2011, <https://www.rfc-
editor.org/info/rfc6049>. [RFC6049]
Section 3.4 of [RFC7679] provides the reference definition of the
singleton (single value) one-way delay metric. Section 4.4 of
[RFC7679] provides the reference definition expanded to cover a
multi-value sample. Note that terms such as "singleton" and "sample"
are defined in section 2 of [RFC2330].
With the OP [RFC7011] typically located between the hosts
participating in the IP connection, the one-way delay metric requires
one individual measurement between the OP and sourcing host, such
that the Spatial Composition [RFC6049] of the measurements yields a
one-way delay singleton.
2.2.2. Fixed Parameters
Traffic Filters:
IPv4 header values:
DSCP: Set to 0
IPv6 header values:
DSCP: Set to 0
Hop Count: Set to 255
Flow Label: Set to 0
Extension Headers: None
2.3. Method of Measurement
This category includes columns for references to relevant sections of
the RFC(s) and any supplemental information needed to ensure an
unambiguous method for implementations.
2.3.1. Reference Methods
The foundational methodology for this metric is defined in section 4
of [RFC7323] using the Timestamps option with modifications that
allow application at a mid-path OP [RFC7011].
The Traffic Filter at the OP is configured to observe a single IP
connection.
2.3.2. Packet Stream Generation
N/A
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2.3.3. Traffic Filtering (Observation) Details
The Fixed Parameters above give a portion of the Traffic Filter.
Other aspects will be supplied as Runtime Parameters (below).
2.3.4. Sampling Distribution
This metric requires a partial sample of all packets that qualify
according to the Traffic Filter criteria.
2.3.5. Runtime Parameters and Data Format
Runtime Parameters are input factors that must be determined,
configured into the measurement system, and reported with the results
for the context to be complete.
Src: The IP address of the host in the host A Role (format
ipv4-address-no-zone value for IPv4 or ipv6-address-no-zone value
for IPv6; see section 4 of [RFC6991].
Dst: The IP address of the host in the host B Role (format
ipv4-address-no-zone value for IPv4 or ipv6-address-no-zone value
for IPv6; see section 4 of [RFC6991].
TTL or Hop Limit: Set at desired value.
DSCP: Set at desired value.
IPv6 Flow Label: Set at desired value.
Timestamp: The timestamp when the packet is being received at IOAM
encapsulation node. Format depends on Inband Telemetry
implementation. For IOAM, Section 4.4.1 of [RFC9197] describes
what kind of timestamps are supported. Section 4.4.2.3 and
4.4.2.4 describe where the timestamp is being inserted. For Path
Tracing, Section 4.1 of [I-D.filsfils-spring-path-tracing]
describes what kind of timestamps are supported. Section 9.2
describe the SRH path tracing TLV where the timestamp is being
inserted.
2.3.6. Roles
host A: Launches the IP packet to open the connection. The Role of
"host A" is synonymous with the IP address used at host A.
host B: Receives the IP packet to open the connection. The Role of
"host B" is synonymous with the IP address used at host B.
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Encapsulation Node: Receives the IP packet to open the connection
and encapsulates the timestamp into the packet. The Role of
"Encapsulation Node" is synonymous with the timestamp inserted in
the packet.
Transit Node: Receives the IP packet to open the connection and
measures the delay between the timestamp in the packet and the
timestamp when the packet was received.
Decapsulation Node: Receives the IP packet to open the connection
and measures the delay between the timestamp in the packet and the
timestamp when the packet was received and removes the IOAM header
from the packet.
2.4. Output
This category specifies all details of the output of measurements
using the metric.
2.4.1. Type
OWDelay Types are discussed in the subsections below.
2.4.2. Reference Definition
For all output types:
OWDelay_HybridType1_Passive_IP: The one-trip delay of one IP packet
is a Singleton
For each <statistic>, Singleton one of the following subsections
applies.
2.4.2.1. Mean
The mean SHALL be calculated using the conditional distribution of
all packets with a finite value of one-way delay (undefined delays
are excluded) -- a single value, as follows:
See section 4.1 of [RFC3393] for details on the conditional
distribution to exclude undefined values of delay, and see section 5
of [RFC6703] for background on this analysis choice.
See section 4.2.2 of [RFC6049] for details on calculating this
statistic; see also section 4.2.3 of [RFC6049].
Mean: The time value of the result is expressed in units of seconds,
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as a positive value of type decimal64 with fraction digits = 9
(see section 9.3 of [RFC6020]) with a resolution of
0.000000001 seconds (1.0 ns), and with lossless conversion to/from
the 64-bit NTP timestamp as per section 6 of [RFC5905].
2.4.2.2. Min
The minimum SHALL be calculated using the conditional distribution of
all packets with a finite value of one-way delay (undefined delays
are excluded) -- a single value, as follows:
See section 4.1 of [RFC3393] for details on the conditional
distribution to exclude undefined values of delay, and see section 5
of [RFC6703] for background on this analysis choice.
See section 4.3.2 of [RFC6049] for details on calculating this
statistic; see also section 4.3.3 of [RFC6049].
Min: The time value of the result is expressed in units of seconds,
as a positive value of type decimal64 with fraction digits = 9
(see section 9.3 of [RFC6020]) with a resolution of
0.000000001 seconds (1.0 ns), and with lossless conversion to/from
the 64-bit NTP timestamp as per section 6 of [RFC5905].
2.4.2.3. Max
The maximum SHALL be calculated using the conditional distribution of
all packets with a finite value of one-way delay (undefined delays
are excluded) -- a single value, as follows:
See section 4.1 of [RFC3393] for details on the conditional
distribution to exclude undefined values of delay, and see section 5
of [RFC6703] for background on this analysis choice.
See section 4.3.2 of [RFC6049] for a closely related method for
calculating this statistic; see also section 4.3.3 of [RFC6049]. The
formula is as follows:
Max = (FiniteDelay[j])
such that for some index, j, where 1 <= j <= N
FiniteDelay[j] >= FiniteDelay[n] for all n
Max: The time value of the result is expressed in units of seconds,
as a positive value of type decimal64 with fraction digits = 9
(see section 9.3 of [RFC6020]) with a resolution of
0.000000001 seconds (1.0 ns), and with lossless conversion to/from
the 64-bit NTP timestamp as per section 6 of [RFC5905].
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2.4.2.4. Sum
The sum SHALL be calculated using the conditional distribution of all
packets with a finite value of one-way delay (undefined delays are
excluded) -- a single value, as follows:
See section 4.1 of [RFC3393] for details on the conditional
distribution to exclude undefined values of delay, and see section 5
of [RFC6703] for background on this analysis choice.
See section 4.3.5 of [RFC6049] for details on calculating this
statistic. However in this case FiniteDelay or MaxDelay MAY be used.
Sum: The time value of the result is expressed in units of seconds,
as a positive value of type decimal64 with fraction digits = 9
(see section 9.3 of [RFC6020]) with a resolution of
0.000000001 seconds (1.0 ns), and with lossless conversion to/from
the 64-bit NTP timestamp as per section 6 of [RFC5905].
2.4.2.5. Metric Units
The <statistic> of one-way delay is expressed in seconds, where
<statistic> is one of:
* Mean
* Min
* Max
* Sum
The one-way delay of the IP connection singleton is expressed in
seconds.
2.4.2.6. Calibration
Passive Measurements at an OP could be calibrated against an Active
Measurement at host A where the Active Measurement represents the
ground truth.
2.4.3. Administrative Items
2.4.3.1. Status
Current
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2.4.3.2. Requester
This RFC
2.4.3.3. Revision
1.0
2.4.3.4. Revision Date
RFC Date
2.4.4. Comments and Remarks
None
3. IPFIX Information Elements
This section defines and describes the new IPFIX IEs.
PathDelayMeanDeltaMicroseconds
16-bit unsigned integer that identifies the mean path delay in
microseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelayMeanDeltaNanoseconds
32-bit unsigned integer that identifies the mean path delay in
nanoseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelayMinDeltaMicroseconds
16-bit unsigned integer that identifies the lowest path delay in
microseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelayMinDeltaNanoseconds
32-bit unsigned integer that identifies the lowest path delay in
nanoseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
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PathDelayMaxDeltaMicroseconds
16-bit unsigned integer that identifies the highest path delay in
microseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelayMaxDeltaNanoseconds
32-bit unsigned integer that identifies the highest path delay in
nanoseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelaySumDeltaMicroseconds
32-bit unsigned integer that identifies the sum of the path delay
in microseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
PathDelaySumDeltaNanoseconds
64-bit unsigned integer that identifies the sum of the path delay
in nanoseconds, between the IOAM encapsulation node and the local
node with the IOAM domain (either an IOAM transit node or an IOAM
decapsulation node).
4. Use Cases
The measured forwarding path delay can be aggregated with Flow
Aggregation as defined in [RFC7015] to the following device and
control-plane dimensions to determine:
* With node id and egressInterface(IE14), on which node which
logical egress interfaces have been contributing to how much
delay.
* With node id and egressPhysicalInterface(253), on which node which
physical egress interfaces have been contributing to how much
delay.
* With ipNextHopIPv4Address(IE15) or ipNextHopIPv6Address(IE62), the
forwarding path to which next-hop IP contributed to how much
delay.
* With mplsTopLabelIPv4Address(IE47) or srhActiveSegmentIPv6 from
[I-D.tgraf-opsawg-ipfix-srv6-srh], the forwarding path to which
MPLS top label IPv4 address or SRv6 active segment contributed to
how much delay.
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* BGP communities are often used for setting a path priority or
service selection. With bgpDestinationExtendedCommunityList(488)
or bgpDestinationCommunityList(485) or
bgpDestinationLargeCommunityList(491) which group of prefixes
accumulated at which node how much delay.
* With destinationIPv4Address(13), destinationTransportPort(11),
protocolIdentifier (4) and sourceIPv4Address(IE8), the forwarding
path delay on each node from each IPv4 source address to a
specific application in the network.
Taking figure 1 from section 1 as topology example. Below example
table shows the aggregated delay per each node, egressInterface and
srhActiveSegmentIPv6.
+------------+------+-----------------+----------------------+
| Path Delay | Node | egressInterface | srhActiveSegmentIPv6 |
+------------+------+-----------------+----------------------+
| 0 ns | R1 | 276 | 2001:db8::4 |
+------------+------+-----------------+----------------------+
| 3122 ns | R2 | 312 | 2001:db8::4 |
+------------+------+-----------------+----------------------+
| 4432 ns | R3 | 27 | 2001:db8::4 |
+------------+------+-----------------+----------------------+
| 7237 ns | R4 | 854 | 2001:db8::4 |
+------------+------+-----------------+----------------------+
Table 2: Example table of measured delay. Ascending by delay.
5. IANA Considerations
5.1. Performance Metrics
This document requests IANA to create new performance metrics under
the "Performance Metrics" registry [RFC8911] with the values defined
in section 2.
5.2. IPFIX Entities
This document requests IANA to create new IEs (see table 3) under the
"IPFIX Information Elements" registry [RFC7012] available at "IANA
Performance Metric Registry [IANA-PERF-METRIC] and assign the
following initial code points.
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+-------+--------------------------------+
|Element| Name |
| ID | |
+-------+--------------------------------+
| TBD5 | PathDelayMeanDeltaMicroseconds |
| | |
+-------+--------------------------------+
| TBD6 | PathDelayMeanDeltaNanoseconds |
| | |
+-------+--------------------------------+
| TBD7 | PathDelayMinDeltaMicroseconds |
| | |
+-------+--------------------------------+
| TBD8 | PathDelayMinDeltaNanoseconds |
| | |
+-------+--------------------------------+
| TBD9 | PathDelayMaxDeltaMicroseconds |
| | |
+-------+--------------------------------+
| TBD10 | PathDelayMaxDeltaNanoseconds |
| | |
+-------+--------------------------------+
| TBD11 | PathDelaySumDeltaMicroseconds |
| | |
+-------+--------------------------------+
| TBD12 | PathDelaySumDeltaNanoseconds |
| | |
+-------+--------------------------------+
Table 3: Creates IEs in the "IPFIX Information Elements" registry
Note to the RFC-Editor:
* Please replace TBD5 - TBD12 with the values allocated by IANA
* Please replace the [RFC-to-be] with the RFC number assigned to
this document
5.2.1. PathDelayMeanDeltaMicroseconds
Name: PathDelayMeanDeltaMicroseconds ElementID: TBD5 Description:
This Information Element identifies the mean path delay between the
IOAM encapsulation node and the local node with the IOAM domain
(either an IOAM transit node or an IOAM decapsulation node) in
microseconds. Abstract Data Type: unsigned16 Data Type Semantics:
OctedDelta Reference: [RFC-to-be], xxx
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5.2.2. PathDelayMeanDeltaNanoseconds
Name: PathDelayMeanDeltaNanoseconds ElementID: TBD6 Description: This
Information Element identifies the mean path delaybetween the IOAM
encapsulation node and the local node with the IOAM domain (either an
IOAM transit node or an IOAM decapsulation node) in nanoseconds.
Abstract Data Type: unsigned32 Data Type Semantics: OctedDelta
Reference: [RFC-to-be], xxx
5.2.3. PathDelayMinDeltaMicroseconds
Name: PathDelayMinDeltaMicroseconds ElementID: TBD7 Description: This
Information Element identifies the lowest path delay between the IOAM
encapsulation node and the local node with the IOAM domain (either an
IOAM transit node or an IOAM decapsulation node) in microseconds.
Abstract Data Type: unsigned16 Data Type Semantics: OctedDelta
Reference: [RFC-to-be], xxx
5.2.4. PathDelayMinDeltaNanoseconds
Name: PathDelayMinDeltaNanoseconds ElementID: TBD8 Description: This
Information Element identifies the lowest path delay between the IOAM
encapsulation node and the local node with the IOAM domain (either an
IOAM transit node or an IOAM decapsulation node) in nanoseconds.
Abstract Data Type: unsigned32 Data Type Semantics: OctedDelta
Reference: [RFC-to-be], xxx
5.2.5. PathDelayMaxDeltaMicroseconds
Name: PathDelayMaxDeltaMicroseconds ElementID: TBD9 Description: This
Information Element identifies the highest path delay between the
IOAM encapsulation node and the local node with the IOAM domain
(either an IOAM transit node or an IOAM decapsulation node) in
microseconds. Abstract Data Type: unsigned16 Data Type Semantics:
OctedDelta Reference: [RFC-to-be], xxx
5.2.6. PathDelayMaxDeltaNanoseconds
Name: PathDelayMaxDeltaNanoseconds ElementID: TBD10 Description: This
Information Element identifies the highest path delay between the
IOAM encapsulation node and the local node with the IOAM domain
(either an IOAM transit node or an IOAM decapsulation node) in
nanoseconds. Abstract Data Type: unsigned32 Data Type Semantics:
OctedDelta Reference: [RFC-to-be], xxx
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5.2.7. PathDelaySumDeltaMicroseconds
Name: PathDelaySumDeltaMicroseconds ElementID: TBD11 Description:
This Information Element identifies the sum of the path delay between
the IOAM encapsulation node and the local node with the IOAM domain
(either an IOAM transit node or an IOAM decapsulation node) in
microseconds. Abstract Data Type: unsigned32 Data Type Semantics:
OctedDelta Reference: [RFC-to-be], xxx
5.2.8. PathDelaySumDeltaNanoseconds
Name: PathDelaySumDeltaNanoseconds ElementID: TBD12 Description: This
Information Element identifies the sum of the path delay between the
IOAM encapsulation node and the local node with the IOAM domain
(either an IOAM transit node or an IOAM decapsulation node) in
nanoseconds. Abstract Data Type: unsigned64 Data Type Semantics:
OctedDelta Reference: [RFC-to-be], xxx
6. Operational Considerations
6.1. Time Accuracy
The same recommendation as defined in section 4.5 of [RFC5153] for
IPFIX applies in terms of clock precision to this document as well.
6.2. Mean Delay
The mean (average) path delay can be calculated by dividing the
PathDelaySumDeltaMicroseconds(TBD5) or
PathDelaySumDeltaNanoseconds(TBD6) by the packetDeltaCount(2) at the
IPFIX data collection.
6.3. IOAM Packet Time Stamps
For IOAM, Section 4.4.1 of [RFC9197] describes what kind of
timestamps are supported. Section 4.4.2.3 and 4.4.2.4 describe where
the timestamp is being inserted.
For Path Tracing, Section 4.1 of [I-D.filsfils-spring-path-tracing]
describes what kind of timestamps are supported. Section 9.2
describe the SRH path tracing TLV where the timestamp is being
inserted.
7. Security Considerations
There are no significant extra security considerations regarding the
allocation of these new IPFIX IEs compared to [RFC7012].
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8. Acknowledgements
The authors would like to thank xxx for their review and valuable
comments.
9. References
9.1. Normative References
[IANA-PERF-METRIC]
"IANA Performance Metric Registry",
<https://www.iana.org/assignments/performance-metrics/
performance-metrics.xhtml>.
[RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model
for IP Flow Information Export (IPFIX)", RFC 7012,
DOI 10.17487/RFC7012, September 2013,
<https://www.rfc-editor.org/info/rfc7012>.
[RFC8911] Bagnulo, M., Claise, B., Eardley, P., Morton, A., and A.
Akhter, "Registry for Performance Metrics",
DOI 10.17487/RFC8911, RFC 8911, November 2021,
<https://www.rfc-editor.org/info/rfc8911>.
9.2. Informative References
[I-D.filsfils-spring-path-tracing]
Filsfils, C., Abdelsalam, A., Garvia, P. C., Yufit, M.,
Graf, T., Su, Y., Matsushima, S., and M. Valentine, "Path
Tracing in SRv6 networks", Work in Progress, Internet-
Draft, draft-filsfils-spring-path-tracing-01, 30 May 2022,
<https://www.ietf.org/archive/id/draft-filsfils-spring-
path-tracing-01.txt>.
[I-D.ietf-ippm-ioam-deployment]
Brockners, F., Bhandari, S., Bernier, D., and T. Mizrahi,
"In-situ OAM Deployment", Work in Progress, Internet-
Draft, draft-ietf-ippm-ioam-deployment-01, 11 April 2022,
<https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-
deployment-01.txt>.
[I-D.song-ippm-postcard-based-telemetry]
Song, H., Mirsky, G., Filsfils, C., Abdelsalam, A., Zhou,
T., Li, Z., Mishra, G., Shin, J., and K. Lee, "In-Situ OAM
Marking-based Direct Export", Work in Progress, Internet-
Draft, draft-song-ippm-postcard-based-telemetry-12, 12 May
2022, <https://www.ietf.org/archive/id/draft-song-ippm-
postcard-based-telemetry-12.txt>.
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[I-D.song-opsawg-ifit-framework]
Song, H., Qin, F., Chen, H., Jin, J., and J. Shin, "A
Framework for In-situ Flow Information Telemetry", Work in
Progress, Internet-Draft, draft-song-opsawg-ifit-
framework-17, 22 February 2022,
<https://www.ietf.org/archive/id/draft-song-opsawg-ifit-
framework-17.txt>.
[I-D.tgraf-opsawg-ipfix-srv6-srh]
Graf, T., Claise, B., and P. Francois, "Export of Segment
Routing IPv6 Information in IP Flow Information Export
(IPFIX)", Work in Progress, Internet-Draft, draft-tgraf-
opsawg-ipfix-srv6-srh-05, 24 July 2022,
<https://www.ietf.org/archive/id/draft-tgraf-opsawg-ipfix-
srv6-srh-05.txt>.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
"Framework for IP Performance Metrics", RFC 2330,
DOI 10.17487/RFC2330, May 1998,
<https://www.rfc-editor.org/info/rfc2330>.
[RFC3393] Demichelis, C. and P. Chimento, "IP Packet Delay Variation
Metric for IP Performance Metrics (IPPM)", RFC 3393,
DOI 10.17487/RFC3393, November 2002,
<https://www.rfc-editor.org/info/rfc3393>.
[RFC5153] Boschi, E., Mark, L., Quittek, J., Stiemerling, M., and P.
Aitken, "IP Flow Information Export (IPFIX) Implementation
Guidelines", RFC 5153, DOI 10.17487/RFC5153, April 2008,
<https://www.rfc-editor.org/info/rfc5153>.
[RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
"Network Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
<https://www.rfc-editor.org/info/rfc5905>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6049] Morton, A. and E. Stephan, "Spatial Composition of
Metrics", RFC 6049, DOI 10.17487/RFC6049, January 2011,
<https://www.rfc-editor.org/info/rfc6049>.
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[RFC6703] Morton, A., Ramachandran, G., and G. Maguluri, "Reporting
IP Network Performance Metrics: Different Points of View",
DOI 10.17487/RFC6703, RFC 6703, August 2012,
<https://www.rfc-editor.org/info/rfc6703>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken,
"Specification of the IP Flow Information Export (IPFIX)
Protocol for the Exchange of Flow Information", STD 77,
RFC 7011, DOI 10.17487/RFC7011, September 2013,
<https://www.rfc-editor.org/info/rfc7011>.
[RFC7015] Trammell, B., Wagner, A., and B. Claise, "Flow Aggregation
for the IP Flow Information Export (IPFIX) Protocol",
DOI 10.17487/RFC7015, RFC 7015, September 2013,
<https://www.rfc-editor.org/info/rfc7015>.
[RFC7323] Borman, D., Braden, B., Jacobson, V., and R.
Scheffenegger, Ed., "TCP Extensions for High Performance",
DOI 10.17487/RFC7323, RFC 7323, September 2014,
<https://www.rfc-editor.org/info/rfc7323>.
[RFC7679] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
Ed., "A One-Way Delay Metric for IP Performance Metrics
(IPPM)", STD 81, RFC 7679, DOI 10.17487/RFC7679, January
2016, <https://www.rfc-editor.org/info/rfc7679>.
[RFC9197] Brockners, F., Ed., Bhandari, S., Ed., and T. Mizrahi,
Ed., "Data Fields for In Situ Operations, Administration,
and Maintenance (IOAM)", DOI 10.17487/RFC9197, RFC 9197,
May 2022, <https://www.rfc-editor.org/info/rfc9197>.
Authors' Addresses
Thomas Graf
Swisscom
Binzring 17
CH-8045 Zurich
Switzerland
Email: thomas.graf@swisscom.com
Benoit Claise
Huawei
Email: benoit.claise@huawei.com
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Alex Huang Feng
INSA-Lyon
Lyon
France
Email: alex.huang-feng@insa-lyon.fr
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