IOAM Direct Exporting (DEX) Option Extensions for Incorporating the Alternate-Marking Method
draft-he-ippm-ioam-dex-extensions-incorporating-am-05
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | hexiaoming , Frank Brockners , Haoyu Song , Giuseppe Fioccola , Aijun Wang | ||
| Last updated | 2026-08-29 | ||
| Replaces | draft-he-ippm-integrating-am-into-ioam | ||
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draft-he-ippm-ioam-dex-extensions-incorporating-am-05
IPPM Working Group X. He
Internet-Draft China Telecom
Intended status: Standards Track F. Brockners
Expires: 1 March 2027 Cisco
H. Song
Futurewei
G. Fioccola
Huawei
A. Wang
China Telecom
28 August 2026
IOAM Direct Exporting (DEX) Option Extensions for Incorporating the
Alternate-Marking Method
draft-he-ippm-ioam-dex-extensions-incorporating-am-05
Abstract
In situ Operations, Administration, and Maintenance (IOAM) is used
for recording and collecting operational and telemetry information.
Specifically, passport-based IOAM allows telemetry data generated by
each node along the path to be pushed into data packets when they
traverse the network, while postcard-based IOAM allows IOAM data
generated by each node to be directly exported without being pushed
into in-flight data packets. The Alternate-Marking method is used to
measure performance metrics on live traffic, such as packet loss,
delay, and jitter. This document extends IOAM Direct Export (DEX)
Option-Type to integrate the Alternate-Marking Method into IOAM to
augment IOAM in performance measurement.
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 1 March 2027.
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Copyright Notice
Copyright (c) 2026 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
3. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 4
4. Integrate the Alternate-Marking Method into IOAM DEX
Option . . . . . . . . . . . . . . . . . . . . . . . . . 5
5. The Extended DEX Option-Type Format . . . . . . . . . . . . . 5
6. The IOAM Operation . . . . . . . . . . . . . . . . . . . . . 7
6.1. Packet Loss Measurement . . . . . . . . . . . . . . . . . 8
6.2. Packet Delay Measurement . . . . . . . . . . . . . . . . 9
7. Flow Identification . . . . . . . . . . . . . . . . . . . . . 10
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
8.1. IOAM Type . . . . . . . . . . . . . . . . . . . . . . . . 11
8.2. IOAM DEX Extension-Flags . . . . . . . . . . . . . . . . 12
9. Performance Considerations . . . . . . . . . . . . . . . . . 12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
11.1. Normative References . . . . . . . . . . . . . . . . . . 13
11.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
IOAM [RFC9197], which defines two possible IOAM Trace Option-Types:
Pre-allocated Trace, Incremental Trace, is used for monitoring
traffic in the network and for incorporating IOAM data fields into
in-flight data packets. IOAM [RFC9197] is known as the passport
mode, in which each node on the path can add telemetry data to the
user packets (i.e., stamps the passport). IOAM Direct Export (DEX)
[RFC9326] is used as a trigger for IOAM nodes to directly export IOAM
data to a receiving entity such as a collector, analyzer, or
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controller. IOAM DEX is also referred as the postcard mode, in which
each node directly exports the telemetry data using an independent
packet (i.e., sends a postcard) while the user packets are
unmodified.
The limitation of the passport mode lies in that if a packet is lost
on the path, the collected IOAM data will also be lost. So the
passport mode such as IOAM Trace Option-Type is unable to monitor
packet loss and its location.
IOAM DEX Option-Type can complement IOAM Trace Option-Type. Even if
a packet is lost on the path, the partial data collected is still
available. By correlating the data from different nodes, the number
of the lost packets can be counted accurately and packet drop
location can also be pinpointed.
The Alternate-Marking [RFC9341] technique has been proven to work
well to perform packet loss, delay, and jitter measurements on live
traffic. RFC9343 describes how the Alternate-Marking Method can be
used to measure performance metrics in IPv6. It defines an Extension
Header Option to encode Alternate-Marking information in both the
Hop-by-Hop Options Header and Destination Options Header.
This document presents the problems and challenges currently faced by
IOAM in measuring performance metrics such as packet loss, delay, and
jitter. In order to augment IOAM in performance measurement, IOAM
DEX Option-Type is extended to incorporate the Alternate-Marking
method into IOAM.
2. Conventions
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.
2.2. Terminology
Abbreviations used in this document:
DEX: Direct Exporting
FlowMonID: Flow Monitoring Identification
IOAM: In situ Operation, Administration, and Maintenance
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MPN: Measurement Period Number
OAM: Operation, Administration, and Maintenance
SN: Sequence Number
3. Problem Statement
Although IOAM DEX Option-Type can complement IOAM Trace Option-Type
for monitoring packet loss, some issues have to be considered as
follows.
* Measurement accuracy: In theory, when an IOAM encapsulating node
incorporates the DEX Option-Type into all the traffic it forwards,
the fidelity of packet loss measurement can be guaranteed. If
only a very small traffic subset or an excessively low traffic
sampling rate is implemented on an encapsulating node, loss
measurement results will not reflect the actual packet loss, since
packet loss caused by instantaneous congestion such as microburst
may not be detected. Therefore, a higher traffic sampling rate
can help improve measurement accuracy.
* Performance impact: If an IOAM encapsulating node incorporates the
DEX Option-Type into all the traffic of interest it forwards, it
may lead to an excessive amount of exported data, which may
significantly occupy network bandwidth and overload the receiving
entity. On the other hand, because the IOAM data of the same user
packet is generated by every node along the path, the receiving
entity needs more processing overhead to correlate these data for
packet loss calculation. The more user packets being measured,
the more processing overhead is required. Therefore, an IOAM
encapsulating node that supports the DEX Option-Type must also
support the ability to incorporate the DEX Option-Type selectively
into a subset of the packets that are forwarded by the IOAM
encapsulating node.
* Measurement methodology: When using the Alternate-Marking method,
traffic flows are split into consecutive blocks: each block
represents a measurable entity unambiguously recognizable by all
network devices along the path. In contrast, according to IOAM
DEX Option-Type, every IOAM node directly exports an IOAM data to
a receiving entity when every user packet is forwarded, and the
collected IOAM data are not split into independent measurement
blocks. It is the receiving entity's responsibility to determine
the measurement period for performance metrics such as packet
loss, delay, and jitter, which is not beneficial to a unified
measurement methodology.
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4. Integrate the Alternate-Marking Method into IOAM DEX Option
To address the issues and challenges mentioned in Section 3, IOAM
needs to be augmented to implement performance measurement. The
Alternate-Marking method has been widely employed in operator
networks. By integrating the Alternate-Marking method into IOAM DEX
Option-Type, the benefits gained include:
* Guaranteed measurement accuracy: When implementing performance
measurement using the Alternate-Marking method, an IOAM
encapsulating node may incorporate the DEX Option-Type into all
packets of the measured user traffic it forwards, and could color
all the traffic of interest, not a subset of the packets, thus the
fidelity of performance measurement such as packet loss can be
guaranteed.
* Minimal performance impact: When using the Alternate-Marking
method for loss measurement, in Hop-by-Hop mode, every node along
the path exports only a packet carrying counter value of each
measurement block including a batch of packets; In End-to-End
mode, only the IOAM encapsulating node and the IOAM decapsulating
node export a packet carrying counter value of each measurement
block. As a result, it significantly mitigates the network and
the receiving entity. Furthermore, compared to IOAM DEX Option-
Type, the receiving entity needs much less processing overhead to
correlate these counter values for packet loss computation.
* Unified measurement methodology: When using the Alternate-Marking
method, traffic flows are split into consecutive blocks: each
block represents a measurable entity unambiguously recognizable by
all network devices along the path, thus the measurement period is
completely determined by the encapsulating node. The receiving
entity does not need to concern about how to determine measurement
period, but only compute the result for each measurement period.
It is beneficial to a unified measurement methodology.
* Unified packet header format: Furthermore, by incorporating the
Alternate-Marking method into IOAM DEX Option-Type, only unique
packet header encapsulation format is used for both IOAM trace
monitoring and performance measurement, thus simplifing the
complexity of forwarding chips.
5. The Extended DEX Option-Type Format
The format of the Extended DEX Option-Type is depicted in Figure 1.
All fields are same as DEX Option-Type format defined in RFC9326
except the Reserved field. The Extended DEX Option-Type format uses
the most significant 2 bits of the Reserved field.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | Flags |Extension-Flags|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type |D|L| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow ID (Optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number (Optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Measurement Period Number (Optional) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: The Extended DEX Option-Type Format
Where:
Namespace-ID: 16-bit identifier of the IOAM namespace, as defined in
[RFC9197].
Flags: 8-bit field, comprised of 8 1-bit subfields,as defined in
[RFC9326]. Flags are allocated by IANA.
Extension-Flags: 8-bit field, comprised of 8 1-bit subfields, as
defined in [RFC9326]. Extension-Flags are allocated by IANA. Every
bit in the Extension-Flag field that is set to 1 indicates the
existence of a corresponding optional 4-octet field. Bit 0 (the most
significant bit) and bit 1 in the registry are allocated by
[RFC9326], which are specified as Flow ID and Sequence Number of the
monitored traffic, respectively. Bit 4 (TBA) is specified as
Measurement Period Number in this document. An IOAM node that
receives an extended DEX Option-Type with an unknown flag set to 1
MUST ignore the corresponding optional field.
IOAM-Trace-Type: 24-bit identifier that specifies which IOAM data
types are used and the corresponding IOAM-Data-Fields should be
exported. The format of this field is as defined in [RFC9197].
L: 1-bit Loss flag for Packet Loss Measurement as described in
Section 6.1.
D: 1-bit Delay flag for Single Packet Delay Measurement as described
in Section 6.2.
Reserved: 6-bit field, reserved for future use. These bits MUST be
set to zero on transmission and ignored on receipt.
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Optional fields: The optional fields, if present, reside after the
Reserved field. The order of the optional fields is according to the
order of the respective bits, starting from the most significant bit,
that are enabled in the Extension-Flags field. Each optional field
is 4 octets long.
Flow ID: An optional 32-bit field representing the flow identifier.
If the actual Flow ID is shorter than 32 bits, it is zero padded in
its most significant bits. The field is set at the encapsulating
node and exported to the receiving entity by the forwarding nodes.
The Flow ID can be used to correlate the exported data of the same
flow from multiple nodes and from multiple packets. Flow ID values
are expected to be allocated in a way that avoids collisions. For
example, random assignment of Flow ID values can be subject to
collisions, while centralized allocation can avoid this problem. The
collision probability (CP) for random allocation of Flow ID as well
as the Flow ID allocation solution in the distributed way is detailed
in Setion 7.
Sequence Number: An optional 32-bit sequence number, starting from 0
and incremented by 1 for each packet from the same flow at the
encapsulating node that includes the Extended DEX option. The
Sequence Number, when combined with the Flow ID, provides a
convenient approach to correlate the exported data from the same user
packet.
Measurement Period Number(MPN): An optional 32-bit field representing
the measurement period number of the monitored flow, starting from 0
and incremented by 1 for the specified flow with the same Flow ID.
The field is set at the encapsulating node and exported to the
receiving entity by the forwarding nodes. The MPN, when combined
with the Flow ID, provides a convenient approach to correlate the
exported data of the same flow during the same measurement period
from multiple nodes.
6. The IOAM Operation
The Extended DEX Option-Type SHOULD support the three IOAM operation
modes: only IOAM trace monitoring; only performance measurement;
hybrid.
* Only IOAM trace monitoring: As DEX Option-Type does, an IOAM
encapsulating node that supports the Extended DEX Option-Type MUST
support the ability to incorporate the Extended DEX Option-Type
selectively into a subset of the monitored packets that are
forwarded by the IOAM encapsulating node. At the same time, it
MUST set the corresponding bit flag to 1 in IOAM-Trace-Type field
of the Extended DEX Option-Type so that each node along the path
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needs to generate the specified IOAM data exported to the
receiving entity. Also, it MUST set the L flag and D flag of the
Extended DEX Option-Type to zero on transmit and ignored by the
monitoring nodes.
* Only performance measurement: To ensure the fidelity of
performance measurement, an IOAM encapsulating node MUST
incorporate the Extended DEX Option-Type into all packets of the
measured user traffic it forwards. Like the Alternate-Marking
method [RFC9343], for packet loss measurement, it MUST switch the
value of the L bit between 0 and 1 after a fixed number of packets
or according to a fixed timer; for packet delay measurement,
Single-Marking or Double-Marking methodology can be adopted by
switching the value of the L bit or D bit between 0 and 1. But it
MUST set all 24 bits flag to 0 in IOAM-Trace-Type field of the
Extended DEX Option-Type so that each node along the path does not
need to generate the IOAM data exported to the receiving entity.
* Hybrid: To perform both IOAM trace monitoring and performance
measurement concurrently, an IOAM encapsulating node MUST
incorporate the Extended DEX Option-Type into all the traffic of
interest it forwards. For performance measurement, an IOAM
encapsulating node MUST mark each packet it forwards in L flag and
D flag of the Extended DEX Option-Type; for IOAM trace monitoring,
only a subset of the packets are selected by an IOAM encapsulating
node. For every selected packet, an IOAM encapsulating node MUST
set corresponding bit flag to 1 in IOAM-Trace-Type field of the
Extended DEX Option-Type so that each node along the path needs to
generate the specified IOAM data exported to the receiving entity;
for all the other packets not selected, an IOAM encapsulating node
MUST set all 24 bits flag to 0 in IOAM- Trace-Type field of the
Extended DEX Option-Type, such that each node along the path does
not need to generate the IOAM data exported to the receiving
entity.
6.1. Packet Loss Measurement
The measurement of the packet loss is detailed in [RFC9341]and
[RFC9343]. The packets of the flow identified by Flow ID are grouped
into batches, and all the packets within a batch are marked by
setting the L bit (Loss flag) to a same value. The source node (IOAM
encapsulating node) can switch the value of the L bit between 0 and 1
after a fixed number of packets or according to a fixed timer, and
this depends on the implementation. The source node is the only one
that marks the packets to create the batches, while the intermediate
nodes only read the marking values and identify the packet batches.
By counting the number of packets in each batch and comparing the
values measured by different network nodes along the path, it is
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possible to measure the packet loss that occurred in any single batch
between any two nodes. Each batch represents a measurable entity
recognizable by all network nodes along the path, which export the
counter value of this batch along with the Flow ID and the MPN (if
present) to the receiving entity (e.g., the collector).
By employing the optional MPN field, it provides a simpler and
accurate approach for the receiving entity to correlate the packet
counter values belonging to the same measurement block (or
measurement period) from different nodes, especially in the case
where milliseconds-level measurement block for real-time network
performance monitoring is required, e.g., Precision Availability
Metrics (PAM) described in RFC9544.
6.2. Packet Delay Measurement
Delay metrics may be calculated using the following two
possibilities:
Single-Marking Methodology: This approach uses only the L bit to
calculate both packet loss and delay. In this case, the D flag MUST
be set to zero on transmit and ignored by the monitoring nodes. The
alternation of the values of the L bit can be used as a time
reference to calculate the delay. Whenever the L bit changes and a
new batch starts, a network node can store the timestamp of the first
packet of the new batch; that timestamp can be compared with the
timestamp of the first packet of the same batch on a second node to
compute packet delay. However, this measurement is accurate only
when the first packet of the new batch has not experienced packet
loss or packet reordering.
Double-Marking Methodology: This approach is to use the first marking
with the L bit to create the alternate batch and, within the batches
identified by the L bit, a second marking with the D bit set to 1 is
used to select the packets for measuring delay. The D bit creates a
new set of marked packets that are fully identified over the network
so that a forwarding node can store and export the timestamps of
these packets, and these timestamps can be compared with the
timestamps of the same packets on a second node to compute packet
delay values for each packet. Compared to selecting a single double-
marked packet for each batch, which may lead to an invalid delay
result if this double-marked packet is lost, selecting multiple
double-marked packets for each measurement batch provides a robust
and accurate method for packet delay measurement. Furthermore, the
average delay for multiple double-marked packets can also be obtained
for every measurement period.
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Sequence Number can be used to identify the same packet with multiple
timestamps from different nodes in case of packet reordering. Also,
it can be used to identify which double-marked packet is lost when
loss occurs.
In summary, the approach with Double-Marking is better than the
approach with Single-Marking. In the implementation, the timestamps
along with Flow ID, MPN and Sequence Number (if present) can be sent
out to the receiving entity that is responsible for the calculation.
7. Flow Identification
The Flow Identification (Flow ID) identifies the flow to be measured
and is required for some general reasons, which is described in
Section 5.3 of [RFC9343]. [RFC9343] uses 20-bit FlowMonID to
determine a monitored flow within the measurement domain. Compared
to the FlowMonID, the Flow ID in this document is a 32-bit field,
which amplifies the FlowMonID space by 4096 times. Accordingly, a
chance of collision is greatly reduced in a distributed way.
When the 32-bit Flow ID is used for every source node, if there are N
edge nodes (source nodes) in a large-scale operator network, and each
source node can generate a unique Flow ID for every measured flow
independently and randomly in a distributed way. Assuming that each
node randomly generates M different Flow IDs from the available K
flow identification space, then the total possible sample space (PSS)
is
the Nth power of C (K, M) (1)
and the total possible sample space without overlapping (PSSno)is
C1 (K, M)*C2 (K-M, M )*....*CN (k-(N-1)M, M) (2)
Theoritically, the collision probability (CP) is calculated as:
CP=1-PSSno/PSS (3)
Take K=32nd power of 2 as an example, which corresponds to 32-bit
Flow ID space. When the number N and M are given different values,
we can obtain the corresponding CP values shown in the following
table.
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+----------------+--------+--------+--------+--------+--------+--------+
| | N=100 | N=100 | N=200 | N=200 | N=200 | N=200 |
| 32-bit Flow ID +--------+--------+--------+--------+--------+--------+
| | M=100 | M=200 | M=200 | M=300 | M=400 | M=500 |
+----------------+-------------+-------------+-------------+-----------+
| CP | 0.0115 | 0.0453 | 0.1692 | 0.3410 | 0.5235 | 0.6860 |
+----------------+--------+--------+--------+--------+--------+--------+
It is not difficult to observe that as the number of concurrent
monitored flows increases, the collision probability is rapidly
increasing. As shown in the table, when generating 10000 concurrent
flows, the CP is 0.0115; when generating 100000 concurrent flows, the
CP rises to 0.6860. If K=20th power of 2 is taken, which corresponds
to 20-bit Flow ID space, when generating 10000 concurrent flows, we
can calculate the collision probability will drastically rises to
approximately 100%. In practical deployment scenarios of large-scale
networks, the concurrent measurement flows could reach orders of
magnitude of 100000 or even higher, thus the collision probability
will rise sharply.
It is preferred that Flow ID be assigned by the centralized
controller. Since the controller knows the network topology, it can
allocate the value properly to guarantee the uniqueness of Flow ID
allocation.
In some cases where the centralized controller is not available and
the distributed way must be adopted, every source node (encapsulating
node) needs to allocate Flow ID independently. In order to avoid the
collision, Flow ID field may be devided into two sub-fields: NodeID
and FlowMonID. NodeID is assigned uniquely in measurement domain (by
the unified planning) and FlowMonID is assigned randomly and uniquely
in a device. The length allocation of the two sub-fields depends on
practical implementation, for example, NodeID uses 20 bits and
FlowMonID uses 12 bits, or both use an average of 16 bits.
8. IANA Considerations
8.1. IOAM Type
The "IOAM Option-Type" registry is defined in Section 7.1 of
[RFC9197].
IANA is requested to allocate the following code point from the "IOAM
Option-Type" registry as follows:
Code Point: TBA.
Name: IOAM Extended DEX Option Type.
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Description: Direct exporting.
Reference: This document.
If possible, IANA is requested to allocate code point 5(TBA-type).
8.2. IOAM DEX Extension-Flags
IANA has created the "IOAM DEX Extension-Flags" registry. This
registry includes 8 flag bits. Bit 0 (the most significant bit) and
bit 1 in the registry are allocated by [RFC9326]. Bit 2 and Bit 3 in
the registry are allocated by [RFC9630].
IANA is requested to allocate the following bit from the "IOAM DEX
Extension-Flags" registry as follows:
Bit: 4 (TBA).
Description: Measurement Period Number (MPN).
Reference: This document.
9. Performance Considerations
The Extended DEX Option-Type triggers IOAM data (including IOAM trace
data and performance measurement data) to be collected and/or to be
exported to a receiving entity. In some cases, this may impact the
receiving entity's performance.
Therefore, the performance impact of these exported packets is
limited by taking two measures: at the encapsulating nodes by
selective DEX encapsulation and at the transit nodes by limiting
exporting rate, which are detailed in [RFC9326]. These two measures
ensure that direct exporting is used at a rate that does not
significantly affect the network bandwidth and does not overload the
receiving entity.
When performance measurement is implemented based on the Alternate-
Marking Method, in Hop-by-Hop mode for loss measurement, every node
along the path exports only a packet carrying counter value of each
measurement block containing a batch of packets; In End-to-End mode
for loss measurement, only the IOAM encapsulating node and the IOAM
decapsulating node export a packet carrying counter value of each
measurement block. Meanwhile, an IOAM encapsulating node only needs
to select a very small subset of the packets that are forwarded for
IOAM trace monitoring (e.g., 1/10000 of all the traffic), so the
amount of exported data is significantly reduced to mitigate the
network and the receiving entity. Compared with IOAM DEX Option-Type
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for packet loss calculation, due to a significant reduction in the
number of exported packets, the receiving entity needs much less
processing overhead to correlate these counter values for packet loss
computation.
10. Security Considerations
The security considerations of IOAM in general are discussed in
[RFC9197], the security considerations of IOAM DEX Option-Type are
discussed in [RFC9326], and the security considerations of the
Alternate-Marking method are discussed in [RFC9394]. There are not
additional security considerations in this Extended IOAM DEX Option-
Type.
11. References
11.1. 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>.
[RFC9197] Brockners, F., Ed., Bhandari, S., Ed., and T. Mizrahi,
Ed., "Data Fields for In Situ Operations, Administration,
and Maintenance (IOAM)", RFC 9197, DOI 10.17487/RFC9197,
May 2022, <https://www.rfc-editor.org/info/rfc9197>.
[RFC9326] Song, H., Gafni, B., Brockners, F., Bhandari, S., and T.
Mizrahi, "In Situ Operations, Administration, and
Maintenance (IOAM) Direct Exporting", RFC 9326,
DOI 10.17487/RFC9326, November 2022,
<https://www.rfc-editor.org/info/rfc9326>.
[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>.
[RFC9343] Fioccola, G., Zhou, T., Cociglio, M., Qin, F., and R.
Pang, "IPv6 Application of the Alternate-Marking Method",
RFC 9343, DOI 10.17487/RFC9343, December 2022,
<https://www.rfc-editor.org/info/rfc9343>.
He, et al. Expires 1 March 2027 [Page 13]
Internet-Draft IOAM Direct Exporting (DEX) Option Exten August 2026
11.2. Informative References
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC9486] Bhandari, S., Ed. and F. Brockners, Ed., "IPv6 Options for
In Situ Operations, Administration, and Maintenance
(IOAM)", RFC 9486, DOI 10.17487/RFC9486, September 2023,
<https://www.rfc-editor.org/info/rfc9486>.
Authors' Addresses
Xiaoming He
China Telecom
Email: hexm4@chinatelecom.cn
Frank Brockners
Cisco
Email: fbrockne@cisco.com
Haoyu Song
Futurewei
Email: haoyu.song@futurewei.com
Giuseppe Fioccola
Huawei
Email: giuseppe.fioccola@huawei.com
Aijun Wang
China Telecom
Email: wangaj3@chinatelecom.cn
He, et al. Expires 1 March 2027 [Page 14]