IPPM Working Group X. Min
Internet-Draft G. Mirsky
Intended status: Standards Track ZTE Corp.
Expires: April 28, 2020 L. Bo
China Telecom
October 26, 2019
Echo Request/Reply for In-situ OAM Capabilities
draft-xiao-ippm-ioam-conf-state-05
Abstract
This document describes an extension to the echo request/reply
mechanisms used in IPv6, SR-MPLS and SFC environments, which can be
used within an IOAM domain, allowing the IOAM encapsulating node to
acquire IOAM capabilities of each IOAM transit node and/or IOAM
decapsulating node.
Status of This Memo
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This Internet-Draft will expire on April 28, 2020.
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions Used in This Document . . . . . . . . . . . . 3
1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3
1.1.2. Requirements Language . . . . . . . . . . . . . . . . 4
2. IOAM Capabilities Formats . . . . . . . . . . . . . . . . . . 4
2.1. IOAM Capabilities TLV in Echo Request . . . . . . . . . . 4
2.2. IOAM Capabilities TLV in Echo Reply . . . . . . . . . . . 5
2.2.1. IOAM Pre-allocated Tracing Capabilities sub-TLV . . . 6
2.2.2. IOAM Incremental Tracing Capabilities sub-TLV . . . . 7
2.2.3. IOAM Proof of Transit Capabilities sub-TLV . . . . . 8
2.2.4. IOAM Edge-to-Edge Capabilities sub-TLV . . . . . . . 9
2.2.5. IOAM End-of-Domain sub-TLV . . . . . . . . . . . . . 11
3. Operational Guide . . . . . . . . . . . . . . . . . . . . . . 11
4. Security Considerations . . . . . . . . . . . . . . . . . . . 12
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
7. Normative References . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
The Data Fields for In-situ OAM (IOAM) [I-D.ietf-ippm-ioam-data]
defines data fields for IOAM which records OAM information within the
packet while the packet traverses a particular network domain, which
is called an IOAM domain. IOAM can be used to complement OAM
mechanisms based on, e.g., ICMP or other types of probe packets, and
IOAM mechanisms can be leveraged where mechanisms using, e.g., ICMP
do not apply or do not offer the desired results.
As specified in [I-D.ietf-ippm-ioam-data], within the IOAM-domain,
the IOAM data may be updated by network nodes that the packet
traverses. The device which adds an IOAM data container to the
packet to capture IOAM data is called the "IOAM encapsulating node",
whereas the device which removes the IOAM data container is referred
to as the "IOAM decapsulating node". Nodes within the domain which
are aware of IOAM data and read and/or write or process the IOAM data
are called "IOAM transit nodes". Both the IOAM encapsulating node
and the decapsulating node are referred to as domain edge devices,
which can be hosts or network devices.
In order to add accurate IOAM data container to the packet, the IOAM
encapsulating node needs to know IOAM capabilities at the IOAM
transit nodes and/or the IOAM decapsulating node as a whole, e.g.,
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how many IOAM transit nodes will add tracing data and what kinds of
data fields will be added.
This document describes an extension to the echo request/reply
mechanisms used in IPv6, SR-MPLS and SFC environments, which can be
used within an IOAM domain, allowing the IOAM encapsulating node to
acquire IOAM capabilities of each IOAM transit node and/or IOAM
decapsulating node.
The following documents contain references to the echo request/reply
mechanisms used in IPv6, SR-MPLS and SFC environments:
o [RFC4884] ("Extended ICMP to Support Multi-Part Messages") and
[RFC8335] ("PROBE: A Utility for Probing Interfaces")
o [RFC8029] ("Detecting Multiprotocol Label Switched (MPLS) Data-
Plane Failures")
o [I-D.ietf-sfc-multi-layer-oam] ("Active OAM for Service Function
Chains in Networks")
The feature described in this document is assumedly applied to
explicit path (strict or loose), because the precondition for this
feature to work is that the echo request reaches each IOAM transit
node as live traffic traverses.
1.1. Conventions Used in This Document
1.1.1. Terminology
E2E: Edge to Edge
ICMP: Internet Control Message Protocol
IOAM: In-situ Operations, Administration, and Maintenance
LSP: Label Switched Path
MPLS: Multi-Protocol Label Switching
MBZ: Must Be Zero
MTU: Maximum Transmission Unit
NTP: Network Time Protocol
OAM: Operations, Administration, and Maintenance
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POSIX: Portable Operating System Interface
POT: Proof of Transit
PTP: Precision Time Protocol
SFC: Service Function Chain
SR-MPLS: Segment Routing with MPLS Data plane
TTL: Time to Live
1.1.2. 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. IOAM Capabilities Formats
2.1. IOAM Capabilities TLV in Echo Request
In echo request IOAM Capabilities uses TLV (Type-Length-Value tuple)
which have the following format:
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 = IOAM Capabilities | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-IDs Length | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
. List of Namespace-IDs .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: IOAM Capabilities TLV in Echo Request
When this TLV is present in the echo request sent by an IOAM
encapsulating node, it means that the IOAM encapsulating node
requests the receiving node to reply with its IOAM capabilities. If
there is no IOAM capability to be reported by the receiving node,
then this TLV SHOULD be ignored by the receiving node, which means
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the receiving node SHOULD send echo reply without IOAM capabilities
or no echo reply, in the light of whether the echo request includes
other TLV than IOAM Capabilities TLV. List of Namespace-IDs MAY be
included in this TLV of echo request, it means that the IOAM
encapsulating node requests only the IOAM capabilities which matches
one of the Namespace-IDs. The Namespace-ID has the same definition
as what's specified in [I-D.ietf-ippm-ioam-data].
Type is set to the value which indicates that it's an IOAM
Capabilities TLV.
Length is the length of the TLV's Value field in octets, Namespace-
IDs Length is the Length of the List of Namespace-IDs field in
octets.
Value field of this TLV is zero padded to align to a 4-octet
boundary.
2.2. IOAM Capabilities TLV in Echo Reply
In echo reply IOAM Capabilities uses TLV which have the following
format:
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 = IOAM Capabilities | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs Length | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
. List of Sub-TLVs .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: IOAM Capabilities TLV in Echo Reply
When this TLV is present in the echo reply sent by an IOAM transit
node and/or an IOAM decapsulating node, it means that IOAM function
is enabled at this node and this TLV contains IOAM capabilities of
the sender. List of Sub-TLVs which contain the IOAM capabilities
SHOULD be included in this TLV of the echo reply. Note that the IOAM
encapsulating node or the IOAM decapsulating node can also be an IOAM
transit node.
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Type is set to the value which indicates that it's an IOAM
Capabilities TLV.
Length is the length of the TLV's Value field in octets, Sub-TLVs
Length is the length of the List of Sub-TLVs field in octets.
Value field of this TLV or any Sub-TLV is zero padded to align to a
4-octet boundary. Based on the data fields for IOAM specified in
[I-D.ietf-ippm-ioam-data], five kinds of Sub-TLVs are defined in this
document, and in an IOAM Capabilities TLV the same kind of Sub-TLV
can appear more times than one with different Namespace-ID. Note
that the IOAM encapsulating node may receive both IOAM Pre-allocated
Tracing Capabilities sub-TLV and IOAM Incremental Tracing
Capabilities sub-TLV in the process of traceroute, which means both
pre-allocated tracing node and incremental tracing node are on the
same path, or some node supports both pre-allocated tracing and
incremental tracing, the behavior of the IOAM encapsulating node in
this scenario is outside the scope of this document.
2.2.1. IOAM Pre-allocated Tracing Capabilities sub-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Sub-type = Pre-allocated trace | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | Egress_MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Egress_if_id (short or wide format) ...... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: IOAM Pre-allocated Tracing Capabilities Sub-TLV
When this sub-TLV is present in the IOAM Capabilities TLV, it means
that the sending node is an IOAM transit node and IOAM tracing
function is enabled at this IOAM transit node.
Sub-type is set to the value which indicates that it's an IOAM Pre-
allocated Tracing Capabilities sub-TLV.
Length is the length of the sub-TLV's Value field in octets, if
Egress_if_id is in the short format which is 16 bits long, it MUST be
set to 10, and if Egress_if_id is in the wide format which is 32 bits
long, it MUST be set to 12.
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IOAM-Trace-Type field has the same definition as what's specified in
section 4.4 of [I-D.ietf-ippm-ioam-data].
Reserved field is reserved for future use and MUST be set to zero.
Namespace-ID field has the same definition as what's specified in
section 4.4 of [I-D.ietf-ippm-ioam-data], it should be one of the
Namespace-IDs listed in the IOAM Capabilities TLV of echo request.
Egress_MTU field has 16 bits and specifies the MTU of the egress
direction out of which the sending node would forward the received
echo request, it should be the MTU of the egress interface or the MTU
between the sending node and the downstream IOAM transit node.
Egress_if_id field has 16 bits (in short format) or 32 bits (in wide
format) and specifies the identifier of the egress interface out of
which the sending node would forward the received echo request.
2.2.2. IOAM Incremental Tracing Capabilities sub-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type = Incremental trace | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | Egress_MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Egress_if_id (short or wide format) ...... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: IOAM Incremental Tracing Capabilities Sub-TLV
When this sub-TLV is present in the IOAM Capabilities TLV, it means
that the sending node is an IOAM transit node and IOAM tracing
function is enabled at this IOAM transit node.
Sub-type is set to the value which indicates that it's an IOAM
Incremental Tracing Capabilities sub-TLV.
Length is the length of the sub-TLV's Value field in octets, if
Egress_if_id is in the short format which is 16 bits long, it MUST be
set to 10, and if Egress_if_id is in the wide format which is 32 bits
long, it MUST be set to 12.
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IOAM-Trace-Type field has the same definition as what's specified in
section 4.4 of [I-D.ietf-ippm-ioam-data].
Reserved field is reserved for future use and MUST be set to zero.
Namespace-ID field has the same definition as what's specified in
section 4.4 of [I-D.ietf-ippm-ioam-data], it should be one of the
Namespace-IDs listed in the IOAM Capabilities TLV of echo request.
Egress_MTU field has 16 bits and specifies the MTU of the egress
direction out of which the sending node would forward the received
echo request, it should be the MTU of the egress interface or the MTU
between the sending node and the downstream IOAM transit node.
Egress_if_id field has 16 bits (in short format) or 32 bits (in wide
format) and specifies the identifier of the egress interface out of
which the sending node would forward the received echo request.
2.2.3. IOAM Proof of Transit Capabilities sub-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type = POT Capabilities | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | IOAM-POT-Type |P|SoR|Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: IOAM Proof of Transit Capabilities Sub-TLV
When this sub-TLV is present in the IOAM Capabilities TLV, it means
that the sending node is an IOAM transit node and IOAM proof of
transit function is enabled at this IOAM transit node.
Sub-type is set to the value which indicates that it's an IOAM Proof
of Transit Capabilities sub-TLV.
Length is the length of the sub-TLV's Value field in octets, and MUST
be set to 4.
Namespace-ID field has the same definition as what's specified in
section 4.5 of [I-D.ietf-ippm-ioam-data], it should be one of the
Namespace-IDs listed in the IOAM Capabilities TLV of echo request.
IOAM-POT-Type field and P bit have the same definition as what's
specified in section 4.5 of [I-D.ietf-ippm-ioam-data]. If the IOAM
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encapsulating node receives IOAM-POT-Type and/or P bit values from an
IOAM transit node that are different from its own, then the IOAM
encapsulating node MAY choose to abandon the proof of transit
function or to select one kind of IOAM-POT-Type and P bit, it's based
on the policy applied to the IOAM encapsulating node.
SoR field has two bits which means the size of "Random" and
"Cumulative" data, which are specified in section 4.5 of
[I-D.ietf-ippm-ioam-data]. This document defines SoR as follow:
0b00 means 64-bit "Random" and 64-bit "Cumulative" data.
0b01~0b11: Reserved for future standardization
Reserved field is reserved for future use and MUST be set to zero.
2.2.4. IOAM Edge-to-Edge Capabilities sub-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type = E2E Capabilities | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | IOAM-E2E-Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TSF|TSL| Reserved | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: IOAM Edge-to-Edge Capabilities Sub-TLV
When this sub-TLV is present in the IOAM Capabilities TLV, it means
that the sending node is an IOAM decapsulating node and IOAM edge-to-
edge function is enabled at this IOAM decapsulating node. That is to
say, if the IOAM encapsulating node receives this sub-TLV, the IOAM
encapsulating node can determine that the node which sends this sub-
TLV is an IOAM decapsulating node.
Sub-type is set to the value which indicates that it's an IOAM Edge-
to-Edge Capabilities sub-TLV.
Length is the length of the sub-TLV's Value field in octets, and MUST
be set to 8.
Namespace-ID field has the same definition as what's specified in
section 4.6 of [I-D.ietf-ippm-ioam-data], it should be one of the
Namespace-IDs listed in the IOAM Capabilities TLV of echo request.
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IOAM-E2E-Type field has the same definition as what's specified in
section 4.6 of [I-D.ietf-ippm-ioam-data].
TSF field specifies the timestamp format used by the sending node.
This document defines TSF as follow:
0b00: PTP timestamp format
0b01: NTP timestamp format
0b10: POSIX timestamp format
0b11: Reserved for future standardization
TSL field specifies the timestamp length used by the sending node.
This document defines TSL as follow:
When TSF field is set to 0b00 which indicates PTP timestamp
format:
0b00: 64-bit PTPv1 timestamp as defined in IEEE1588-2008
[IEEE1588v2]
0b01: 80-bit PTPv2 timestamp as defined in IEEE1588-2008
[IEEE1588v2]
0b10~0b11: Reserved for future standardization
When TSF field is set to 0b01 which indicates NTP timestamp
format:
0b00: 32-bit NTP timestamp as defined in NTPv4 [RFC5905]
0b01: 64-bit NTP timestamp as defined in NTPv4 [RFC5905]
0b10: 128-bit NTP timestamp as defined in NTPv4 [RFC5905]
0b11: Reserved for future standardization
When TSF field is set to 0b10 or 0b11, the TSL field would be
ignored.
Reserved field is reserved for future use and MUST be set to zero.
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2.2.5. IOAM End-of-Domain sub-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-type = End of Domain | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Namespace-ID | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: IOAM End of Domain Sub-TLV
When this sub-TLV is present in the IOAM Capabilities TLV, it means
that the sending node is an IOAM decapsulating node. That is to say,
if the IOAM encapsulating node receives this sub-TLV, the IOAM
encapsulating node can determine that the node which sends this sub-
TLV is an IOAM decapsulating node. When the IOAM Edge-to-Edge
Capabilities sub-TLV is present in the IOAM Capabilities TLV sent by
the IOAM decapsulating node, the IOAM End-of-Domain sub-TLV doesn't
need to be present in the same IOAM Capabilities TLV, otherwise the
End-of-Domain sub-TLV MUST be present in the IOAM Capabilities TLV
sent by the IOAM decapsulating node. Since both the IOAM Edge-to-
Edge Capabilities sub-TLV and the IOAM End-of-Domain sub-TLV can be
used to indicate that the sending node is an IOAM decapsulating node,
it's recommended to include only the IOAM Edge-to-Edge Capabilities
sub-TLV if IOAM edge-to-edge function is enabled at this IOAM
decapsulating node.
Length is the length of the sub-TLV's Value field in octets, and MUST
be set to 4.
Namespace-ID field has the same definition as what's specified in
section 4.6 of [I-D.ietf-ippm-ioam-data], it should be one of the
Namespace-IDs listed in the IOAM Capabilities TLV of echo request.
3. Operational Guide
Once the IOAM encapsulating node is triggered to acquire IOAM
capabilities of each IOAM transit node and/or IOAM decapsulating
node, the IOAM encapsulating node will send a batch of echo requests
that include the IOAM Capabilities TLV, first with TTL equal to 1 to
reach the nearest node which may be an IOAM transit node or not, then
with TTL equal to 2 to reach the second nearest node which also may
be an IOAM transit node or not, on the analogy of this to increase 1
to TTL every time the IOAM encapsulating node sends a new echo
request, until the IOAM encapsulating node receives echo reply sent
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by the IOAM decapsulating node, which should contain the IOAM
Capabilities TLV including the IOAM Edge-to-Edge Capabilities sub-TLV
or the IOAM End-of-Domain sub-TLV. Alternatively, if the IOAM
encapsulating node knows exactly all the IOAM transit nodes and/or
IOAM decapsulating node beforehand, once the IOAM encapsulating node
is triggered to acquire IOAM capabilities, it can send echo request
to each IOAM transit node and/or IOAM decapsulating node directly,
without TTL expiration.
The IOAM encapsulating node may be triggered by the device
administrator, the network management system, the network controller,
or even the live user traffic, and the specific triggering mechanisms
are outside the scope of this document.
Each IOAM transit node and/or IOAM decapsulating node that receives
an echo request containing the IOAM Capabilities TLV will send an
echo reply to the IOAM encapsulating node, and within the echo reply,
there should be an IOAM Capabilities TLV containing one or more sub-
TLVs. The IOAM Capabilities TLV contained in the echo request would
be ignored by the receiving node that is unaware of IOAM.
4. Security Considerations
Knowledge of the state of the IOAM domain may be considered
confidential. Implementations SHOULD provide a means of filtering
the addresses to which echo request/reply may be sent.
5. IANA Considerations
This document has no IANA actions.
6. Acknowledgements
The authors would like to acknowledge Tianran Zhou for his careful
review and helpful comments.
The authors appreciate the f2f discussion with Frank Brockners on
this document.
7. Normative References
[I-D.ietf-ippm-ioam-data]
Brockners, F., Bhandari, S., Pignataro, C., Gredler, H.,
Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov,
P., remy@barefootnetworks.com, r., daniel.bernier@bell.ca,
d., and J. Lemon, "Data Fields for In-situ OAM", draft-
ietf-ippm-ioam-data-08 (work in progress), October 2019.
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[I-D.ietf-sfc-multi-layer-oam]
Mirsky, G., Meng, W., Khasnabish, B., and C. Wang, "Active
OAM for Service Function Chains in Networks", draft-ietf-
sfc-multi-layer-oam-03 (work in progress), May 2019.
[IEEE1588v2]
Institute of Electrical and Electronics Engineers, "IEEE
Std 1588-2008 - IEEE Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and
Control Systems", IEEE Std 1588-2008, 2008,
<http://standards.ieee.org/findstds/
standard/1588-2008.html>.
[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>.
[RFC4884] Bonica, R., Gan, D., Tappan, D., and C. Pignataro,
"Extended ICMP to Support Multi-Part Messages", RFC 4884,
DOI 10.17487/RFC4884, April 2007,
<https://www.rfc-editor.org/info/rfc4884>.
[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>.
[RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
Switched (MPLS) Data-Plane Failures", RFC 8029,
DOI 10.17487/RFC8029, March 2017,
<https://www.rfc-editor.org/info/rfc8029>.
[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>.
[RFC8335] Bonica, R., Thomas, R., Linkova, J., Lenart, C., and M.
Boucadair, "PROBE: A Utility for Probing Interfaces",
RFC 8335, DOI 10.17487/RFC8335, February 2018,
<https://www.rfc-editor.org/info/rfc8335>.
Authors' Addresses
Min, et al. Expires April 28, 2020 [Page 13]
Internet-Draft Echo Request/Reply for IOAM Capa October 2019
Xiao Min
ZTE Corp.
Nanjing
China
Phone: +86 25 88016574
Email: xiao.min2@zte.com.cn
Greg Mirsky
ZTE Corp.
USA
Email: gregimirsky@gmail.com
Lei Bo
China Telecom
Beijing
China
Phone: +86 10 50902903
Email: leibo@chinatelecom.cn
Min, et al. Expires April 28, 2020 [Page 14]