Internet DRAFT - draft-brockners-inband-oam-data
draft-brockners-inband-oam-data
ippm F. Brockners
Internet-Draft S. Bhandari
Intended status: Standards Track C. Pignataro
Expires: January 3, 2018 Cisco
H. Gredler
RtBrick Inc.
J. Leddy
Comcast
S. Youell
JPMC
T. Mizrahi
Marvell
D. Mozes
Mellanox Technologies Ltd.
P. Lapukhov
Facebook
R. Chang
Barefoot Networks
D. Bernier
Bell Canada
July 2, 2017
Data Fields for In-situ OAM
draft-brockners-inband-oam-data-07
Abstract
In-situ Operations, Administration, and Maintenance (IOAM) records
operational and telemetry information in the packet while the packet
traverses a path between two points in the network. This document
discusses the data fields and associated data types for in-situ OAM.
In-situ OAM data fields can be embedded into a variety of transports
such as NSH, Segment Routing, Geneve, native IPv6 (via extension
header), or IPv4. In-situ OAM can be used to complement OAM
mechanisms based on e.g. ICMP or other types of probe packets.
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 http://datatracker.ietf.org/drafts/current/.
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on January 3, 2018.
Copyright Notice
Copyright (c) 2017 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
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Scope, Applicability, and Assumptions . . . . . . . . . . . . 4
4. IOAM Data Types and Formats . . . . . . . . . . . . . . . . . 5
4.1. IOAM Tracing Options . . . . . . . . . . . . . . . . . . 6
4.1.1. Pre-allocated Trace Option . . . . . . . . . . . . . 8
4.1.2. Incremental Trace Option . . . . . . . . . . . . . . 11
4.1.3. IOAM node data fields and associated formats . . . . 14
4.1.4. Examples of IOAM node data . . . . . . . . . . . . . 19
4.2. IOAM Proof of Transit Option . . . . . . . . . . . . . . 21
4.3. IOAM Edge-to-Edge Option . . . . . . . . . . . . . . . . 23
5. IOAM Data Export . . . . . . . . . . . . . . . . . . . . . . 23
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
6.1. Creation of a New In-Situ OAM
(IOAM) Protocol Parameters IANA registry . . . . . . . . 24
6.2. IOAM Trace Type Registry . . . . . . . . . . . . . . . . 24
6.3. IOAM Trace Flags Registry . . . . . . . . . . . . . . . . 24
6.4. IOAM POT Type Registry . . . . . . . . . . . . . . . . . 25
6.5. IOAM E2E Type Registry . . . . . . . . . . . . . . . . . 25
7. Manageability Considerations . . . . . . . . . . . . . . . . 25
8. Security Considerations . . . . . . . . . . . . . . . . . . . 25
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
10.1. Normative References . . . . . . . . . . . . . . . . . . 25
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10.2. Informative References . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction
This document defines data fields for "in-situ" Operations,
Administration, and Maintenance (IOAM). In-situ OAM records OAM
information within the packet while the packet traverses a particular
network domain. The term "in-situ" refers to the fact that the OAM
data is added to the data packets rather than is being sent within
packets specifically dedicated to OAM. A discussion of the
motivation and requirements for in-situ OAM can be found in
[I-D.brockners-inband-oam-requirements]. IOAM is to complement
mechanisms such as Ping or Traceroute, or more recent active probing
mechanisms as described in [I-D.lapukhov-dataplane-probe]. In terms
of "active" or "passive" OAM, "in-situ" OAM can be considered a
hybrid OAM type. While no extra packets are sent, IOAM adds
information to the packets therefore cannot be considered passive.
In terms of the classification given in [RFC7799] IOAM could be
portrayed as Hybrid Type 1. "In-situ" mechanisms do not require
extra packets to be sent and hence don't change the packet traffic
mix within the network. IOAM mechanisms can be leveraged where
mechanisms using e.g. ICMP do not apply or do not offer the desired
results, such as proving that a certain traffic flow takes a pre-
defined path, SLA verification for the live data traffic, detailed
statistics on traffic distribution paths in networks that distribute
traffic across multiple paths, or scenarios in which probe traffic is
potentially handled differently from regular data traffic by the
network devices.
2. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Abbreviations used in this document:
E2E Edge to Edge
Geneve: Generic Network Virtualization Encapsulation
[I-D.ietf-nvo3-geneve]
IOAM: In-situ Operations, Administration, and Maintenance
MTU: Maximum Transmit Unit
NSH: Network Service Header [I-D.ietf-sfc-nsh]
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OAM: Operations, Administration, and Maintenance
POT: Proof of Transit
SFC: Service Function Chain
SID: Segment Identifier
SR: Segment Routing
VXLAN-GPE: Virtual eXtensible Local Area Network, Generic Protocol
Extension [I-D.ietf-nvo3-vxlan-gpe]
3. Scope, Applicability, and Assumptions
IOAM deployment assumes a set of constraints, requirements, and
guiding principles which are described in this section.
Scope: This document defines the data fields and associated data
types for in-situ OAM. The in-situ OAM data field can be transported
by a variety of transport protocols, including NSH, Segment Routing,
Geneve, IPv6, or IPv4. Specification details for these different
transport protocols are outside the scope of this document.
Deployment domain (or scope) of in-situ OAM deployment: IOAM is a
network domain focused feature, with "network domain" being a set of
network devices or entities within a single administration. For
example, a network domain can include an enterprise campus using
physical connections between devices or an overlay network using
virtual connections / tunnels for connectivity between said devices.
A network domain is defined by its perimeter or edge. Designers of
carrier protocols for IOAM must specify mechanisms to ensure that
IOAM data stays within an IOAM domain. In addition, the operator of
such a domain is expected to put provisions in place to ensure that
IOAM data does not leak beyond the edge of an IOAM domain, e.g. using
for example packet filtering methods. The operator should consider
potential operational impact of IOAM to mechanisms such as ECMP
processing (e.g. load-balancing schemes based on packet length could
be impacted by the increased packet size due to IOAM), path MTU (i.e.
ensure that the MTU of all links within a domain is sufficiently
large to support the increased packet size due to IOAM) and ICMP
message handling (i.e. in case of a native IPv6 transport, IOAM
support for ICMPv6 Echo Request/Reply could desired which would
translate into ICMPv6 extensions to enable IOAM data fields to be
copied from an Echo Request message to an Echo Reply message).
IOAM control points: IOAM data fields are added to or removed from
the live user traffic by the devices which form the edge of a domain.
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Devices within an IOAM domain can update and/or add IOAM data-fields.
Domain edge devices can be hosts or network devices.
Traffic-sets that IOAM is applied to: IOAM can be deployed on all or
only on subsets of the live user traffic. It SHOULD be possible to
enable IOAM on a selected set of traffic (e.g., per interface, based
on an access control list or flow specification defining a specific
set of traffic, etc.) The selected set of traffic can also be all
traffic.
Encapsulation independence: Data formats for IOAM SHOULD be defined
in a transport-independent manner. IOAM applies to a variety of
encapsulating protocols. A definition of how IOAM data fields are
carried by different transport protocols is outside the scope of this
document.
Layering: If several encapsulation protocols (e.g., in case of
tunneling) are stacked on top of each other, IOAM data-records could
be present at every layer. The behavior follows the ships-in-the-
night model.
Combination with active OAM mechanisms: IOAM should be usable for
active network probing, enabling for example a customized version of
traceroute. Decapsulating IOAM nodes may have an ability to send the
IOAM information retrieved from the packet back to the source address
of the packet or to the encapsulating node.
IOAM implementation: The IOAM data-field definitions take the
specifics of devices with hardware data-plane and software data-plane
into account.
4. IOAM Data Types and Formats
This section defines IOAM data types and data fields and associated
data types required for IOAM. The different uses of IOAM require the
definition of different types of data. The IOAM data fields for the
data being carried corresponds to the three main categories of IOAM
data defined in [I-D.brockners-inband-oam-requirements], which are:
edge-to-edge, per node, and for selected nodes only.
Transport options for IOAM data are outside the scope of this memo,
and are discussed in [I-D.brockners-inband-oam-transport]. IOAM data
fields are fixed length data fields. A bit field determines the set
of OAM data fields embedded in a packet. Depending on the type of
the encapsulation, a counter field indicates how many data fields are
included in a particular packet.
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IOAM is expected to be deployed in a specific domain rather than on
the overall Internet. The part of the network which employs IOAM is
referred to as the "IOAM-domain". IOAM data is added to a packet
upon entering the IOAM-domain and is removed from the packet when
exiting the domain. 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". IOAM nodes which add or remove the IOAM data
container can also update the IOAM data fields at the same time. Or
in other words, IOAM encapsulation or decapsulating nodes can also
serve as IOAM transit nodes at the same time. Note that not every
node in an IOAM domain needs to be an IOAM transit node. For
example, a Segment Routing deployment might require the segment
routing path to be verified. In that case, only the SR nodes would
also be IOAM transit nodes rather than all nodes.
4.1. IOAM Tracing Options
"IOAM tracing data" is expected to be collected at every node that a
packet traverses to ensure visibility into the entire path a packet
takes within an IOAM domain, i.e., in a typical deployment all nodes
in an in-situ OAM-domain would participate in IOAM and thus be IOAM
transit nodes, IOAM encapsulating or IOAM decapsulating nodes. If
not all nodes within a domain are IOAM capable, IOAM tracing
information will only be collected on those nodes which are IOAM
capable. Nodes which are not IOAM capable will forward the packet
without any changes to the IOAM data fields. The maximum number of
hops and the minimum path MTU of the IOAM domain is assumed to be
known.
To optimize hardware and software implementations tracing is defined
as two separate options. Any deployment MAY choose to configure and
support one or both of the following options. An implementation of
the transport protocol that carries these in-situ OAM data MAY choose
to support only one of the options. In the event that both options
are utilized at the same time, the Incremental Trace Option MUST be
placed before the Pre-allocated Trace Option. Given that the
operator knows which equipment is deployed in a particular IOAM, the
operator will decide by means of configuration which type(s) of trace
options will be enabled for a particular domain.
Pre-allocated Trace Option: This trace option is defined as a
container of node data fields with pre-allocated space for each
node to populate its information. This option is useful for
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software implementations where it is efficient to allocate the
space once and index into the array to populate the data during
transit. The IOAM encapsulating node allocates the option header
and sets the fields in the option header. The in situ OAM
encapsulating node allocates an array which is used to store
operational data retrieved from every node while the packet
traverses the domain. IOAM transit nodes update the content of
the array. A pointer which is part of the IOAM trace data points
to the next empty slot in the array, which is where the next IOAM
transit node fills in its data.
Incremental Trace Option: This trace option is defined as a
container of node data fields where each node allocates and pushes
its node data immediately following the option header. The
maximum length of the node data list is written into the option
header. This type of trace recording is useful for some of the
hardware implementations as this eliminates the need for the
transit network elements to read the full array in the option and
allows for arbitrarily long packets as the MTU allows. The in-
situ OAM encapsulating node allocates the option header. The in-
situ OAM encapsulating node based on operational state and
configuration sets the fields in the header to control how large
the node data list can grow. IOAM transit nodes push their node
data to the node data list and increment the number of node data
fields in the header.
Every node data entry is to hold information for a particular IOAM
transit node that is traversed by a packet. The in-situ OAM
decapsulating node removes the IOAM data and processes and/or exports
the metadata. IOAM data uses its own name-space for information such
as node identifier or interface identifier. This allows for a
domain-specific definition and interpretation. For example: In one
case an interface-id could point to a physical interface (e.g., to
understand which physical interface of an aggregated link is used
when receiving or transmitting a packet) whereas in another case it
could refer to a logical interface (e.g., in case of tunnels).
The following IOAM data is defined for IOAM tracing:
o Identification of the IOAM node. An IOAM node identifier can
match to a device identifier or a particular control point or
subsystem within a device.
o Identification of the interface that a packet was received on,
i.e. ingress interface.
o Identification of the interface that a packet was sent out on,
i.e. egress interface.
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o Time of day when the packet was processed by the node. Different
definitions of processing time are feasible and expected, though
it is important that all devices of an in-situ OAM domain follow
the same definition.
o Generic data: Format-free information where syntax and semantic of
the information is defined by the operator in a specific
deployment. For a specific deployment, all IOAM nodes should
interpret the generic data the same way. Examples for generic
IOAM data include geo-location information (location of the node
at the time the packet was processed), buffer queue fill level or
cache fill level at the time the packet was processed, or even a
battery charge level.
o A mechanism to detect whether IOAM trace data was added at every
hop or whether certain hops in the domain weren't in-situ OAM
transit nodes.
The "node data list" array in the packet is populated iteratively as
the packet traverses the network, starting with the last entry of the
array, i.e., "node data list [n]" is the first entry to be populated,
"node data list [n-1]" is the second one, etc.
4.1.1. Pre-allocated Trace Option
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In-situ OAM pre-allocated trace option:
Pre-allocated trace option header:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type |NodeLen| Flags | Octets-left |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Pre-allocated Trace Option Data MUST be 4-octet aligned:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
| | |
| node data list [0] | |
| | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ D
| | a
| node data list [1] | t
| | a
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ... ~ S
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ p
| | a
| node data list [n-1] | c
| | e
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | |
| node data list [n] | |
| | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
IOAM-Trace-Type: A 16-bit identifier which specifies which data
types are used in this node data list.
The IOAM-Trace-Type value is a bit field. The following bit
fields are defined in this document, with details on each field
described in the Section 4.1.3. The order of packing the data
fields in each node data element follows the bit order of the
IOAM-Trace-Type field, as follows:
Bit 0 (Most significant bit) When set indicates presence of
Hop_Lim and node_id in the node data.
Bit 1 When set indicates presence of ingress_if_id and
egress_if_id (short format) in the node data.
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Bit 2 When set indicates presence of timestamp seconds in the
node data
Bit 3 When set indicates presence of timestamp nanoseconds in
the node data.
Bit 4 When set indicates presence of transit delay in the node
data.
Bit 5 When set indicates presence of app_data (short format) in
the node data.
Bit 6 When set indicates presence of queue depth in the node
data.
Bit 7 When set indicates presence of variable length Opaque
State Snapshot field.
Bit 8 When set indicates presence of Hop_Lim and node_id in
wide format in the node data.
Bit 9 When set indicates presence of ingress_if_id and
egress_if_id in wide format in the node data.
Bit 10 When set indicates presence of app_data wide in the node
data.
Bit 11 When set indicates presence of the Checksum Complement
node data.
Bit 12-15 Undefined in this draft.
Section 4.1.3 describes the IOAM data types and their formats.
Within an in-situ OAM domain possible combinations of these bits
making the IOAM-Trace-Type can be restricted by configuration
knobs.
Node Data Length: 4-bit unsigned integer. This field specifies the
length of data added by each node in multiples of 4-octets. For
example, if 3 IOAM-Trace-Type bits are set and none of them is
wide, then the Node Data Length would be 3. If 3 IOAM-Trace-Type
bits are set and 2 of them are wide, then the Node Data Length
would be 5.
Flags 5-bit field. Following flags are defined:
Bit 0 "Overflow" (O-bit) (most significant bit). This bit is set
by the network element if there is not enough number of octets
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left to record node data, no field is added and the overflow
"O-bit" must be set to "1" in the header. This is useful for
transit nodes to ignore further processing of the option.
Bit 1 "Loopback" (L-bit). Loopback mode is used to send a copy
of a packet back towards the source. Loopback mode assumes
that a return path from transit nodes and destination nodes
towards the source exists. The encapsulating node decides
(e.g. using a filter) which packets loopback mode is enabled
for by setting the loopback bit. The encapsulating node also
needs to ensure that sufficient space is available in the IOAM
header for loopback operation. The loopback bit when set
indicates to the transit nodes processing this option to create
a copy of the packet received and send this copy of the packet
back to the source of the packet while it continues to forward
the original packet towards the destination. The source
address of the original packet is used as destination address
in the copied packet. The address of the node performing the
copy operation is used as the source address. The L-bit MUST
be cleared in the copy of the packet a nodes sends it back
towards the source. On its way back towards the source, the
packet is processed like a regular packet with IOAM
information. Once the return packet reaches the IOAM domain
boundary IOAM decapsulation occurs as with any other packet
containing IOAM information.
Bit 2-4 Reserved: Must be zero.
Octets-left: 7-bit unsigned integer. It is the data space in
multiples of 4-octets remaining for recording the node data. This
is used as an offset in data space to record the node data
element.
Node data List [n]: Variable-length field. The type of which is
determined by the IOAM-Trace-Type representing the n-th node data
in the node data list. The node data list is encoded starting
from the last node data of the path. The first element of the
node data list (node data list [0]) contains the last node of the
path while the last node data of the node data list (node data
list[n]) contains the first node data of the path traced. The
index contained in "Octets-left" identifies the offset for current
active node data to be populated.
4.1.2. Incremental Trace Option
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In-situ OAM incremental trace option:
In-situ OAM incremental trace option Header:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type |NodeLen| Flags | Max Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IOAM Incremental Trace Option Data MUST be 4-octet aligned:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [0] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [1] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [n-1] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [n] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IOAM-trace-type: A 16-bit identifier which specifies which data
types are used in this node data list.
The IOAM-Trace-Type value is a bit field. The following bit
fields are defined in this document, with details on each field
described in the Section 4.1.3. The order of packing the data
fields in each node data element follows the bit order of the
IOAM-Trace-Type field, as follows:
Bit 0 (Most significant bit) When set indicates presence of
Hop_Lim and node_id in the node data.
Bit 1 When set indicates presence of ingress_if_id and
egress_if_id (short format) in the node data.
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Bit 2 When set indicates presence of timestamp seconds in the
node data.
Bit 3 When set indicates presence of timestamp nanoseconds in
the node data.
Bit 4 When set indicates presence of transit delay in the node
data.
Bit 5 When set indicates presence of app_data in the node data.
Bit 6 When set indicates presence of queue depth in the node
data.
Bit 7 When set indicates presence of variable length Opaque
State Snapshot field.
Bit 8 When set indicates presence of Hop_Lim and node_id wide
in the node data.
Bit 9 When set indicates presence of ingress_if_id and
egress_if_id in wide format in the node data.
Bit 10 When set indicates presence of app_data wide in the node
data.
Bit 11 When set indicates presence of the Checksum Complement
node data.
Bit 12-15 Undefined in this draft.
Section 4.1.3 describes the IOAM data types and their formats.
Node Data Length: 4-bit unsigned integer. This field specifies the
length of data added by each node in multiples of 4-octets. For
example, if 3 IOAM-Trace-Type bits are set and none of them is
wide, then the Node Data Length would be 3. If 3 IOAM-Trace-Type
bits are set and 2 of them are wide, then the Node Data Length
would be 5.
Flags 5-bit field. Following flags are defined:
Bit 0 "Overflow" (O-bit) (least significant bit). This bit is
set by the network element if there is not enough number of
octets left to record node data, no field is added and the
overflow "O-bit" must be set to "1" in the header. This is
useful for transit nodes to ignore further processing of the
option.
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Bit 1 "Loopback" (L-bit). This bit when set indicates to the
transit nodes processing this option to send a copy of the
packet back to the source of the packet while it continues to
forward the original packet towards the destination. The L-bit
MUST be cleared in the copy of the packet before sending it.
Bit 2-4 Reserved. Must be zero.
Maximum Length: 7-bit unsigned integer. This field specifies the
maximum length of the node data list in multiples of 4-octets.
Given that the sender knows the minimum path MTU, the sender can
set the maximum length according to the number of node data bytes
allowed before exceeding the MTU. Thus, a simple comparison
between "Opt data Len" and "Max Length" allows to decide whether
or not data could be added.
Node data List [n]: Variable-length field. The type of which is
determined by the OAM Type representing the n-th node data in the
node data list. The node data list is encoded starting from the
last node data of the path. The first element of the node data
list (node data list [0]) contains the last node of the path while
the last node data of the node data list (node data list[n])
contains the first node data of the path traced.
4.1.3. IOAM node data fields and associated formats
All the data fields MUST be 4-octet aligned. The IOAM encapsulating
node MUST initialize data fields that it adds to the packet to zero.
If a node which is supposed to update an IOAM data field is not
capable of populating the value of a field set in the IOAM-Trace-
Type, the field value MUST be left unaltered except when explicitly
specified in the field description below. In the description of data
below if zero is valid value then a non-zero value to mean not
populated is specified.
Data field and associated data type for each of the data field is
shown below:
Hop_Lim and node_id: 4-octet field defined as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit
value in the packet at the node that records this data. Hop
Limit information is used to identify the location of the node
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in the communication path. This is copied from the lower
layer, e.g., TTL value in IPv4 header or hop limit field from
IPv6 header of the packet when the packet is ready for
transmission. The semantics of the Hop_Lim field depend on the
lower layer protocol that IOAM is encapsulated over, and
therefore its specific semantics are outside the scope of this
memo.
node_id: 3-octet unsigned integer. Node identifier field to
uniquely identify a node within in-situ OAM domain. The
procedure to allocate, manage and map the node_ids is beyond
the scope of this document.
ingress_if_id and egress_if_id: 4-octet field defined as follows:
When this field is part of the data field but a node populating
the field is not able to fill it, the position in the field must
be filled with value 0xFFFFFFFF to mean not populated.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id | egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ingress_if_id: 2-octet unsigned integer. Interface identifier to
record the ingress interface the packet was received on.
egress_if_id: 2-octet unsigned integer. Interface identifier to
record the egress interface the packet is forwarded out of.
timestamp seconds: 4-octet unsigned integer. Absolute timestamp in
seconds that specifies the time at which the packet was received
by the node. The structure of this field is identical to the most
significant 32 bits of the 64 least significant bits of the
[IEEE1588v2] timestamp. This truncated field consists of a 32-bit
seconds field. As defined in [IEEE1588v2], the timestamp
specifies the number of seconds elapsed since 1 January 1970
00:00:00 according to the International Atomic Time (TAI).
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
timestamp nanoseconds: 4-octet unsigned integer in the range 0 to
10^9-1. This timestamp specifies the fractional part of the wall
clock time at which the packet was received by the node in units
of nanoseconds. This field is identical to the 32 least
significant bits of the [IEEE1588v2] timestamp. This fields
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allows for delay computation between any two nodes in the network
when the nodes are time synchronized. When this field is part of
the data field but a node populating the field is not able to fill
it, the field position in the field must be filled with value
0xFFFFFFFF to mean not populated.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp nanoseconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
transit delay: 4-octet unsigned integer in the range 0 to 2^30-1.
It is the time in nanoseconds the packet spent in the transit
node. This can serve as an indication of the queuing delay at the
node. If the transit delay exceeds 2^30-1 nanoseconds then the
top bit 'O' is set to indicate overflow. When this field is part
of the data field but a node populating the field is not able to
fill it, the field position in the field must be filled with value
0xFFFFFFFF to mean not populated.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|O| transit delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
app_data: 4-octet placeholder which can be used by the node to add
application specific data. App_data represents a "free-format"
4-octet bit field with its semantics defined by a specific
deployment.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| app_data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
queue depth: 4-octet unsigned integer field. This field indicates
the current length of the egress interface queue of the interface
from where the packet is forwarded out. The queue depth is
expressed as the current number of memory buffers used by the
queue (a packet may consume one or more memory buffers, depending
on its size). When this field is part of the data field but a
node populating the field is not able to fill it, the field
position in the field must be filled with value 0xFFFFFFFF to mean
not populated.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| queue depth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Opaque State Snapshot: Variable length field. It allows the network
element to store an arbitrary state in the node data field ,
without a pre-defined schema. The schema needs to be made known
to the analyzer by some out-of-band mechanism. The specification
of this mechanism is beyond the scope of this document. The
24-bit "Schema Id" field in the field indicates which particular
schema is used, and should be configured on the network element by
the operator.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Schema ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| Opaque data |
~ ~
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Length: 1-octet unsigned integer. It is the length in octets of
the Opaque data field that follows Schema Id. It MUST always
be a multiple of 4.
Schema ID: 3-octet unsigned integer identifying the schema of
Opaque data.
Opaque data: Variable length field. This field is interpreted as
specified by the schema identified by the Schema ID.
Hop_Lim and node_id wide: 8-octet field defined as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ node_id (contd) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Hop_Lim: 1-octet unsigned integer. It is set to the Hop Limit
value in the packet at the node that records this data. Hop
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Limit information is used to identify the location of the node
in the communication path. This is copied from the lower layer
for e.g. TTL value in IPv4 header or hop limit field from IPv6
header of the packet. The semantics of the Hop_Lim field
depend on the lower layer protocol that IOAM is encapsulated
over, and therefore its specific semantics are outside the
scope of this memo.
node_id: 7-octet unsigned integer. Node identifier field to
uniquely identify a node within in-situ OAM domain. The
procedure to allocate, manage and map the node_ids is beyond
the scope of this document.
ingress_if_id and egress_if_id wide: 8-octet field defined as
follows: When this field is part of the data field but a node
populating the field is not able to fill it, the field position in
the field must be filled with value 0xFFFFFFFFFFFFFFFF to mean not
populated.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ingress_if_id: 4-octet unsigned integer. Interface identifier to
record the ingress interface the packet was received on.
egress_if_id: 4-octet unsigned integer. Interface identifier to
record the egress interface the packet is forwarded out of.
app_data wide: 8-octet placeholder which can be used by the node to
add application specific data. App data represents a "free-
format" 8-octed bit field with its semantics defined by a specific
deployment.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| app data ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ app data (contd) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Checksum Complement: 4-octet node data which contains a two-octet
Checksum Complement field, and a 2-octet reserved field. The
Checksum Complement can be used when IOAM is transported over
encapsulations that make use of a UDP transport, such as VXLAN-GPE
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or Geneve. In this case, incorporating the IOAM node data
requires the UDP Checksum field to be updated. Rather than to
recompute the Chekcsum field, a node can use the Checksum
Complement to make a checksum-neutral update in the UDP payload;
the Checksum Complement is assigned a value that complements the
rest of the node data fields that were added by the current node,
causing the existing UDP Checksum field to remain correct.
Checksum Complement fields are used in a similar manner in
[RFC7820] and [RFC7821].
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum Complement | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.1.4. Examples of IOAM node data
An entry in the "node data list" array can have different formats,
following the needs of the deployment. Some deployments might only
be interested in recording the node identifiers, whereas others might
be interested in recording node identifier and timestamp. The
section defines different types that an entry in "node data list" can
take.
0x002B: IOAM-Trace-Type is 0x2B then the format of node data is:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id | egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp nanoseconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| app_data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0x0003: IOAM-Trace-Type is 0x0003 then the format is:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ingress_if_id | egress_if_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0x0009: IOAM-Trace-Type is 0x0009 then the format is:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp nanoseconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0x0021: IOAM-Trace-Type is 0x0021 then the format is:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| app_data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0x0029: IOAM-Trace-Type is 0x0029 then the format is:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp nanoseconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| app_data |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0x018C: IOAM-Trace-Type is 0x104D then the format is:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp nanoseconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Schema Id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| Opaque data |
~ ~
. .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop_Lim | node_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| node_id(contd) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.2. IOAM Proof of Transit Option
IOAM Proof of Transit data is to support the path or service function
chain [RFC7665] verification use cases. Proof-of-transit uses
methods like nested hashing or nested encryption of the IOAM data or
mechanisms such as Shamir's Secret Sharing Schema (SSSS). While
details on how the IOAM data for the proof of transit option is
processed at IOAM encapsulating, decapsulating and transit nodes are
outside the scope of the document, all of these approaches share the
need to uniquely identify a packet as well as iteratively operate on
a set of information that is handed from node to node.
Correspondingly, two pieces of information are added as IOAM data to
the packet:
o Random: Unique identifier for the packet (e.g., 64-bits allow for
the unique identification of 2^64 packets).
o Cumulative: Information which is handed from node to node and
updated by every node according to a verification algorithm.
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IOAM proof of transit option:
IOAM proof of transit option header:
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|IOAM POT Type|P|
+-+-+-+-+-+-+-+-+
IOAM proof of transit option data MUST be 4-octet aligned:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
| Random | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ P
| Random(contd) | O
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ T
| Cumulative | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| Cumulative (contd) | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
IOAM POT Type: 7-bit identifier of a particular POT variant that
dictates the POT data that is included. This document defines POT
Type 0:
0: POT data is a 16 Octet field as described below.
Profile to use (P): 1-bit. Indicates which POT-profile is used to
generate the Cumulative. Any node participating in POT will have
a maximum of 2 profiles configured that drive the computation of
cumulative. The two profiles are numbered 0, 1. This bit conveys
whether profile 0 or profile 1 is used to compute the Cumulative.
Random: 64-bit Per packet Random number.
Cumulative: 64-bit Cumulative that is updated at specific nodes by
processing per packet Random number field and configured
parameters.
Note: Larger or smaller sizes of "Random" and "Cumulative" data are
feasible and could be required for certain deployments (e.g. in case
of space constraints in the transport protocol used). Future
versions of this document will address different sizes of data for
"proof of transit".
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4.3. IOAM Edge-to-Edge Option
The IOAM edge-to-edge option is to carry data that is added by the
IOAM encapsulating node and interpreted by IOAM decapsulating node.
The IOAM transit nodes MAY process the data without modifying it.
Currently only sequence numbers use the IOAM edge-to-edge option. In
order to detect packet loss, packet reordering, or packet duplication
in an in-situ OAM-domain, sequence numbers can be added to packets of
a particular tube (see [I-D.hildebrand-spud-prototype]). Each tube
leverages a dedicated namespace for its sequence numbers.
IOAM edge-to-edge option:
IOAM edge-to-edge option header:
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
| IOAM-E2E-Type |
+-+-+-+-+-+-+-+-+
IOAM edge-to-edge option data MUST be 4-octet aligned:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| E2E Option data field determined by IOAM-E2E-Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IOAM-E2E-Type: 8-bit identifier of a particular in situ OAM E2E
variant.
0: E2E option data is a 64-bit sequence number added to a
specific tube which is used to identify packet loss and
reordering for that tube.
5. IOAM Data Export
IOAM nodes collect information for packets traversing a domain that
supports IOAM. IOAM decapsulating nodes as well as IOAM transit
nodes can choose to retrieve IOAM information from the packet,
process the information further and export the information using
e.g., IPFIX.
The discussion of IOAM data processing and export is left for a
future version of this document.
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6. IANA Considerations
This document requests the following IANA Actions.
6.1. Creation of a New In-Situ OAM (IOAM) Protocol Parameters IANA
registry
IANA is requested to create a new protocol registry for "In-Situ OAM
(IOAM) Protocol Parameters". This is the common registry that will
include registrations for all IOAM namespaces. Each Registry, whose
names are listed below:
IOAM Trace Type
IOAM Trace flags
IOAM POT Type
IOAM E2E Type
will contain the current set of possibilities defined in this
document. New registries in this name space are created via RFC
Required process as per [RFC8126].
The subsequent sub-sections detail the registries herein contained.
6.2. IOAM Trace Type Registry
This registry defines code point for each bit in the 16-bit IOAM-
Trace-Type field for Pre-allocated trace option and Incremental trace
option defined in Section 4.1. The meaning of Bit 0 - 11 for trace
type are defined in this document in Paragraph 1 of (Section 4.1.1).
The meaning for Bit 12 - 15 are available for assignment via RFC
Required process as per [RFC8126].
6.3. IOAM Trace Flags Registry
This registry defines code point for each bit in the 5 bit flags for
Pre-allocated trace option and Incremental trace option defined in
Section 4.1. The meaning of Bit 0 - 1 for trace flags are defined in
this document in Paragraph 5 of Section 4.1.1. The meaning for Bit 2
- 4 are available for assignment via RFC Required process as per
[RFC8126].
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6.4. IOAM POT Type Registry
This registry defines 128 code points to define IOAM POT Type for
IOAM proof of transit option Section 4.2. The code point value 0 is
defined in this document, 1 - 127 are available for assignment via
RFC Required process as per [RFC8126].
6.5. IOAM E2E Type Registry
This registry defines 256 code points to define IOAM-E2E-Type for
IOAM E2E option Section 4.3. The code point value 0 is defined in
this document, 1 - 255 are available for assignments via RFC Required
process as per [RFC8126].
7. Manageability Considerations
Manageability considerations will be addressed in a later version of
this document..
8. Security Considerations
Security considerations will be addressed in a later version of this
document. For a discussion of security requirements of in-situ OAM,
please refer to [I-D.brockners-inband-oam-requirements].
9. Acknowledgements
The authors would like to thank Eric Vyncke, Nalini Elkins, Srihari
Raghavan, Ranganathan T S, Karthik Babu Harichandra Babu, Akshaya
Nadahalli, LJ Wobker, Erik Nordmark, Vengada Prasad Govindan, and
Andrew Yourtchenko for the comments and advice.
This document leverages and builds on top of several concepts
described in [I-D.kitamura-ipv6-record-route]. The authors would
like to acknowledge the work done by the author Hiroshi Kitamura and
people involved in writing it.
The authors would like to gracefully acknowledge useful review and
insightful comments received from Joe Clarke, Al Morton, and Mickey
Spiegel.
10. References
10.1. Normative References
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[IEEE1588v2]
Institute of Electrical and Electronics Engineers,
"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,
<http://www.rfc-editor.org/info/rfc2119>.
[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,
<http://www.rfc-editor.org/info/rfc8126>.
10.2. Informative References
[I-D.brockners-inband-oam-requirements]
Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
Gredler, H., Leddy, J., Youell, S., Mozes, D., Mizrahi,
T., <>, P., and r. remy@barefootnetworks.com,
"Requirements for In-situ OAM", draft-brockners-inband-
oam-requirements-03 (work in progress), March 2017.
[I-D.brockners-inband-oam-transport]
Brockners, F., Bhandari, S., Govindan, V., Pignataro, C.,
Gredler, H., Leddy, J., Youell, S., Mizrahi, T., Mozes,
D., Lapukhov, P., and R. <>, "Encapsulations for In-situ
OAM Data", draft-brockners-inband-oam-transport-03 (work
in progress), March 2017.
[I-D.hildebrand-spud-prototype]
Hildebrand, J. and B. Trammell, "Substrate Protocol for
User Datagrams (SPUD) Prototype", draft-hildebrand-spud-
prototype-03 (work in progress), March 2015.
[I-D.ietf-nvo3-geneve]
Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic
Network Virtualization Encapsulation", draft-ietf-
nvo3-geneve-04 (work in progress), March 2017.
[I-D.ietf-nvo3-vxlan-gpe]
Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol
Extension for VXLAN", draft-ietf-nvo3-vxlan-gpe-04 (work
in progress), April 2017.
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[I-D.ietf-sfc-nsh]
Quinn, P. and U. Elzur, "Network Service Header", draft-
ietf-sfc-nsh-13 (work in progress), June 2017.
[I-D.kitamura-ipv6-record-route]
Kitamura, H., "Record Route for IPv6 (PR6) Hop-by-Hop
Option Extension", draft-kitamura-ipv6-record-route-00
(work in progress), November 2000.
[I-D.lapukhov-dataplane-probe]
Lapukhov, P. and r. remy@barefootnetworks.com, "Data-plane
probe for in-band telemetry collection", draft-lapukhov-
dataplane-probe-01 (work in progress), June 2016.
[RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
Chaining (SFC) Architecture", RFC 7665,
DOI 10.17487/RFC7665, October 2015,
<http://www.rfc-editor.org/info/rfc7665>.
[RFC7799] Morton, A., "Active and Passive Metrics and Methods (with
Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
May 2016, <http://www.rfc-editor.org/info/rfc7799>.
[RFC7820] Mizrahi, T., "UDP Checksum Complement in the One-Way
Active Measurement Protocol (OWAMP) and Two-Way Active
Measurement Protocol (TWAMP)", RFC 7820,
DOI 10.17487/RFC7820, March 2016,
<http://www.rfc-editor.org/info/rfc7820>.
[RFC7821] Mizrahi, T., "UDP Checksum Complement in the Network Time
Protocol (NTP)", RFC 7821, DOI 10.17487/RFC7821, March
2016, <http://www.rfc-editor.org/info/rfc7821>.
Authors' Addresses
Frank Brockners
Cisco Systems, Inc.
Hansaallee 249, 3rd Floor
DUESSELDORF, NORDRHEIN-WESTFALEN 40549
Germany
Email: fbrockne@cisco.com
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Shwetha Bhandari
Cisco Systems, Inc.
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560 087
India
Email: shwethab@cisco.com
Carlos Pignataro
Cisco Systems, Inc.
7200-11 Kit Creek Road
Research Triangle Park, NC 27709
United States
Email: cpignata@cisco.com
Hannes Gredler
RtBrick Inc.
Email: hannes@rtbrick.com
John Leddy
Comcast
Email: John_Leddy@cable.comcast.com
Stephen Youell
JP Morgan Chase
25 Bank Street
London E14 5JP
United Kingdom
Email: stephen.youell@jpmorgan.com
Tal Mizrahi
Marvell
6 Hamada St.
Yokneam 2066721
Israel
Email: talmi@marvell.com
Brockners, et al. Expires January 3, 2018 [Page 28]
Internet-Draft In-situ OAM Data Fields July 2017
David Mozes
Mellanox Technologies Ltd.
Email: davidm@mellanox.com
Petr Lapukhov
Facebook
1 Hacker Way
Menlo Park, CA 94025
US
Email: petr@fb.com
Remy Chang
Barefoot Networks
2185 Park Boulevard
Palo Alto, CA 94306
US
Daniel
Bell Canada
Email: daniel.bernier@bell.ca
Brockners, et al. Expires January 3, 2018 [Page 29]
