Integrity of In-situ OAM Data Fields
draft-brockners-ippm-ioam-data-integrity-00
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| Authors | Frank Brockners , Shwetha Bhandari , Tal Mizrahi | ||
| Last updated | 2021-01-25 | ||
| Replaced by | draft-ietf-ippm-ioam-data-integrity | ||
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draft-brockners-ippm-ioam-data-integrity-00
ippm F. Brockners
Internet-Draft Cisco
Intended status: Informational S. Bhandari
Expires: July 29, 2021 Thoughtspot
T. Mizrahi
Huawei
January 25, 2021
Integrity of In-situ OAM Data Fields
draft-brockners-ippm-ioam-data-integrity-00
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 is
to assist the IPPM WG in designing a solution for those deployments
where the integrity of IOAM data fields is a concern. This document
proposes several methods to ensure the integrity of IOAM data fields.
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
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 29, 2021.
Copyright Notice
Copyright (c) 2021 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
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to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Threat Analysis . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Modification: IOAM Data Fields . . . . . . . . . . . . . 5
3.2. Modification: IOAM Option-Type Headers . . . . . . . . . 5
3.3. Injection: IOAM Data Fields . . . . . . . . . . . . . . . 6
3.4. Injection: IOAM Option-Type Headers . . . . . . . . . . . 6
3.5. Replay . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.6. Management and Exporting . . . . . . . . . . . . . . . . 6
3.7. Delay . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.8. Threat Summary . . . . . . . . . . . . . . . . . . . . . 7
4. Methods of providing integrity to IOAM data fields . . . . . 8
4.1. Method 1: Using asymmetric keys for signing node trace
data . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1.1. Overhead consideration for Method 1 . . . . . . . . . 10
4.2. Method 2: Using symmetric keys for signing node trace
data . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2.1. Overhead consideration for Method 2 . . . . . . . . . 11
4.3. Method 3: Space optimized symmetric key based signing of
trace data . . . . . . . . . . . . . . . . . . . . . . . 11
4.3.1. Overhead consideration for Method 3 . . . . . . . . . 12
4.4. Method 4: Dynamic symmetric keys based signing of trace
data . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4.1. Overhead consideration for Method 4 . . . . . . . . . 14
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
6. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
"In-situ" Operations, Administration, and Maintenance (IOAM) 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. IOAM is to
complement mechanisms such as Ping, Traceroute, or other active
probing mechanisms. In terms of "active" or "passive" OAM, "in-situ"
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OAM can be considered a hybrid OAM type. "In-situ" mechanisms do not
require extra packets to be sent. IOAM adds information to the
already available data packets and therefore cannot be considered
passive. In terms of the classification given in [RFC7799] IOAM
could be portrayed as Hybrid Type 1. 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.
The current [I-D.ietf-ippm-ioam-data] assumes that IOAM is deployed
in specific network domains, where an operator has means to select,
monitor, and control the access to all the networking devices, making
the domain a trusted network. As such, IOAM tracing data is carried
in the packets in clear and there are no protections against any node
or middlebox tampering with the data. As a consequence, IOAM tracing
data collected in an untrusted or semi-trusted environments cannot be
trusted for critical operational decisions. Any rogue or
unauthorized change to IOAM data fields in a user packet cannot be
detected.
Recent discussions following the IETF last call on
[I-D.ietf-ippm-ioam-data] revealed that there might be uses of IOAM
where integrity protection of IOAM data fields is at least desirable,
knowing that IOAM data fields integrity protection would incur extra
effort in the data path of a device processing IOAM data fields. As
such, the following additional considerations and requirements are to
be taken into account in addition to addressing the problem of
detectability of any integrity breach of the IOAM trace data
collected:
1. IOAM trace data is processed by the data plane, hence viability
of any method to prove integrity of the IOAM trace data must be
feasible at data plane processing/forwarding rates (IOAM data
might be applied to all traffic a router forwards).
2. IOAM trace data is carried within data packets. Additional space
required to prove integrity of the data needs to be optimal, i.e.
should not exceed the MTU or have adverse affect on packet
processing.
3. Replay protection of older IOAM trace data should be possible.
Without replay protection a rogue node can present the old IOAM
trace data masking any ongoing network issues/activity making the
IOAM trace data collection useless.
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This document is to assist the IPPM working group in designing and
specifying a solution for those deployments where the integrity of
IOAM data fields is a concern. This document proposes several
methods to achieve integrity protection for IOAM data fields.
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:
Geneve: Generic Network Virtualization Encapsulation
[I-D.ietf-nvo3-geneve]
GRE Generic Routing Encapsulation
IOAM: In-situ Operations, Administration, and Maintenance
MTU: Maximum Transmit Unit
NSH: Network Service Header [RFC8300]
OAM: Operations, Administration, and Maintenance
POT: Proof of Transit
SFC: Service Function Chain
3. Threat Analysis
This section presents a threat analysis of integrity-related threats
in the context of IOAM. The threats that are discussed are assumed
to be independent of the lower layer protocols; it is assumed that
threats at other layers are handled by security mechanisms that are
deployed at these layers.
This document is focused on integrity protection for IOAM data
fields. Thus the threat analysis includes threats that are related
to or result from compromising the integrity of IOAM data fields.
Other security aspects such as confidentiality are not within the
scope of this document.
Throughout the analysis there is a distinction between on-path and
off-path attackers. As discussed in [I-D.ietf-detnet-security], on-
path attackers are located in a position that allows interception and
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modification of in-flight protocol packets, whereas off-path
attackers can only attack by generating protocol packets.
The analysis also includes the impact of each of the threats.
Generally speaking, the impact of a successful attack on an OAM
protocol [RFC7276] is a false illusion of nonexistent failures or
preventing the detection of actual ones; in both cases, the attack
may result in denial of service (DoS). Furthermore, creating the
false illusion of a nonexistent issue may trigger unnecessary
processing in some of the IOAM nodes along the path, and may cause
more IOAM-related data to be exported to the management plane than is
conventionally necessary. Beyond these general impacts, threat-
specific impacts are discussed in each of the subsections below.
3.1. Modification: IOAM Data Fields
Threat
An attacker can maliciously modify the IOAM data fields of in-
transit packets. The modification can either be applied to all
packets or selectively applied to a subset of the en route
packets. This threat is applicable to on-path attackers.
Impact
By systematically modifying the IOAM data fields of some or all of
the in-transit packets an attacker can create a false picture of
the paths in the network, the existence of faulty nodes and their
location, and the network performance.
3.2. Modification: IOAM Option-Type Headers
Threat
An on-path attacker can modify IOAM data fields in one or more of
the IOAM Option-Type headers in order to change or disrupt the
behavior of nodes processing IOAM data fields along the path.
Impact
Changing the header of IOAM Option-Types may have several
implications. An attacker can maliciously increase the processing
overhead in nodes that process IOAM data fields and increase the
on-the-wire overhead of IOAM data fields, for example by modifying
the IOAM-Trace-Type field in the IOAM Trace-option header. An
attacker can also prevent some of the nodes that process IOAM data
fields from incorporating IOAM data fields by modifying the
RemainingLen field.
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3.3. Injection: IOAM Data Fields
Threat
An attacker can inject packets with IOAM Option-Types and IOAM
data fields. This threat is applicable to both on-path and off-
path attackers.
Impact
This attack and it impacts are similar to Section 3.1.
3.4. Injection: IOAM Option-Type Headers
Threat
An attacker can inject packets with IOAM Option-Type headers, thus
manipulating other nodes that process IOAM data fields in the
network. This threat is applicable to both on-path and off-path
attackers.
Impact
This attack and it impacts are similar to Section 3.2.
3.5. Replay
Threat
An attacker can replay packets with IOAM data fields.
Specifically, an attacker may replay a previously transmitted IOAM
Option-Type with a new data packet, thus attaching old IOAM data
fields to a fresh user packet. This threat is applicable to both
on-path and off-path attackers.
Impact
As with previous threats, this threat may create a false image of
a nonexistent failure, or may overload nodes which process IOAM
data fields with unnecessary processing.
3.6. Management and Exporting
Threat
Attacks that compromise the integrity of IOAM data fields can be
applied at the management plane, e.g., by manipulating network
management packets. Furthermore, the integrity of IOAM data
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fields that are exported to a receiving entity can also be
compromised. Management plane attacks are not within the scope of
this document; the network management protocol is expected to
include inherent security capabilities. The integrity of exported
data is also not within the scope of this document. It is
expected that the specification of the export format will discuss
the relevant security aspects.
Impact
Malicious manipulation of the management protocol can cause nodes
that process IOAM data fields to malfunction, to be overloaded, or
to incorporate unnecessary IOAM data fields into user packets.
The impact of compromising the integrity of exported IOAM data
fields is similar to the impacts of previous threats that were
described in this section.
3.7. Delay
Threat
An on-path attacker may delay some or all of the in-transit
packets that include IOAM data fields in order to create the false
illusion of congestion. Delay attacks are well known in the
context of deterministic networks [I-D.ietf-detnet-security] and
synchronization [RFC7384], and may be somewhat mitigated in these
environments by using redundant paths in a way that is resilient
to an attack along one of the paths. This approach does not
address the threat in the context of IOAM, as it does not meet the
requirement to measure a specific path or to detect a problem
along the path. It is noted that this threat is not within the
scope of the threats that are mitigated in the scope of this
document.
Impact
Since IOAM can be applied to a fraction of the traffic, an
attacker can detect and delay only the packets that include IOAM
data fields, thus preventing the authenticity of delay and load
measurements.
3.8. Threat Summary
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+-------------------------------------------+--------+------------+
| Threat |In scope|Out of scope|
+-------------------------------------------+--------+------------+
|Modification: IOAM Data Fields | + | |
+-------------------------------------------+--------+------------+
|Modification: IOAM Option-Type Headers | + | |
+-------------------------------------------+--------+------------+
|Injection: IOAM Data Fields | + | |
+-------------------------------------------+--------+------------+
|Injection: IOAM Option-Type Headers | + | |
+-------------------------------------------+--------+------------+
|Replay | + | |
+-------------------------------------------+--------+------------+
|Management and Exporting | | + |
+-------------------------------------------+--------+------------+
|Delay | | + |
+-------------------------------------------+--------+------------+
Figure 1: Threat Analysis Summary
4. Methods of providing integrity to IOAM data fields
This section outlines four different methods that are to provide
integrity protection of IOAM data fields. As noted earlier, this
document is to support the IPPM working group in designing and
specifying a method for protecting the integrity of IOAM data fields.
It isn't expected that all four methods would be chosen for a
solution specification.
The discussion of the different methods focuses on protecting the
integrity of IOAM trace data fields, though the outlined methods are
not limited to protecting IOAM trace data fields only. The methods
could be applied to other IOAM Option-Types, such as the E2E Option-
Type.
IOAM trace data can be embedded in a variety of protocols. There are
specific drafts that cover the encapsulation of IOAM data into
different protocols, like IPv6 [I-D.ietf-ippm-ioam-ipv6-options], NSH
[I-D.ietf-sfc-ioam-nsh], Geneve [I-D.brockners-ippm-ioam-geneve],
etc.
The IOAM Option-Types for tracing (Pre-allocated Trace-Option and
Incremental Trace-Option) organize the collected data in an array,
the "node data list". See [I-D.ietf-ippm-ioam-data] for further
details).
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The basic idea is to introduce a new "signed node-data hash field"
added by each node along with the node data to prove the integrity of
the node data inserted.
The following sections describe different methods of how such a
"signed node-data field" could be used and populated. The methods
assume an IOAM-Domain containing IOAM-encapsulating nodes, IOAM-
decapsulating nodes and IOAM-transit nodes. In addition, it is
assumed that traffic also traverses a Validator node, which verifies
the integrity of the IOAM data fields. In a typical deployment, the
IOAM-decapsulating node would also serve as the Validator. The setup
also includes a network management entity/controller which handles
key distributions to the network nodes and also serves as a receiver
for validation results provided by the Validator. Protocols and
procedures for the exchange of keys and validation results between
the network management entity/controller and the nodes are outside
the scope of this document.
4.1. Method 1: Using asymmetric keys for signing node trace data
Method 1 uses asymmetric keys for signing node trace data. This is
the procedure to be followed by each node:
1. Each IOAM capable node creates a key pair and shares the public
key with the controller, the Validator and the network management
system responsible for using the IOAM trace information in the
network domain. The detailed mechanisms how keys are exchanged
between nodes are outside the scope of this document. For
optimal performance, use of algorithms like BLS [BLS] or ED25519
[EdDSA25519] are suggested, resulting in fast signing for small
keys and limited overhead (see below for an overhead
calculation).
2. Each node data list [x] field is extended with an additional
"signed node-data" field: node_data_sign[x]. Node_data_sign
includes a signature using the private key of the node over the
hash of node data list[x] of the node and the previous node's
node data sign node_data_sign[x-1]. This couples the signature
of the current field to the earlier field and creates a chain of
trust. This way of chaining the node data signatures provides
protection against replay of a previous node trace of a specific
node.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| node_data_sign [x] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [x] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3. The IOAM encapsulating node (the node that inserts IOAM data
fields into the packet) will add a seed in its node data list
that is used in its node_data_sign. So the first IOAM node
inserting the IOAM trace data will add node_data_sign over a
"seed" || [hash of node data of first node]. The seed can be
included as a field in first node data or the seed can be the
trailer of the IOAM Trace-Option.
4. The validating node - will use the public key of each node to
validate the signed node data elements in the same way the node
Trace signatures were created, i.e. it'll repeat the individual
operations of the IOAM nodes traversed and will compare the
result to the last node's node_data-sign value. If the two
values match, the IOAM data was not tampered with.
4.1.1. Overhead consideration for Method 1
Assuming e.g Ed25519, the public keys would have a size of 256 bits /
32 bytes, and as such signatures would be 512 bits / 64 bytes wide.
node_data_sign[x] would consume 64 bytes per hop. Note that
depending on the deployment, weaker keys might well apply, given that
the provided integrity check is an online method, i.e. packets are
verified as they arrive. This allows an attacker only a short time-
window.
4.2. Method 2: Using symmetric keys for signing node trace data
The same procedure as Method 1 can be followed by using a MAC
(Message Authentication Code) algorithm for node signature. This
involves distributing a secret key to the individual IOAM nodes and
the Validator. Steps 1 to 4 of Method 1 apply in a similar way, the
only difference is that symmetric keys are used. As such, each node
data list [x] field is extended with an additional "signed node-data"
field: node_data_sign[x]. The size of the node_data_sign[x] field
depends on the cryptographic message authentication code used.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| node_data_sign [x] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [x] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.2.1. Overhead consideration for Method 2
Different types of cryptographic message authentication codes could
be chosen, such as HMAC-SHA256 or Poly1305-AES.
HMAC-SHA256 would take a secret key of any size and provide a 32 byte
authenticator. Consequently, node_data_sign[x] would consume 32
bytes per hop.
Poly1305-AES would use a 32 bytes secret key and provide a 16 byte
authenticator. Consequently, node_data_sign[x] would consume 16
bytes per hop.
4.3. Method 3: Space optimized symmetric key based signing of trace
data
Methods 1 and 2 add a node_data_sign field at every IOAM node the
packet traverses. While feasible for network domains with only a few
IOAM enabled hops, the number of bytes consumed in case of larger
networks might not be acceptable. For those deployments, an approach
with a single fixed sized signature field could apply.
Method 3 enhances the IOAM Trace-Option header to carry a "Trace
Signature" field.
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 |NodeLen | Flags | RemainingLen|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IOAM-Trace-Type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Trace Signature ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Method 3 assumes that symmetric keys have been distributed to the
respective nodes as well as the Validator (the Validator receives all
the keys). The details of the mechanisms of how keys are distributed
are outside the scope of this document. The "Trace Signature" field
is populated as follows:
1. The first node creates a seed and sign/HMAC over the hash of its
node_data_list[x], the seed and its symmetric key. The seed can
be included as a field in first node data or the seed can be the
trailer to the trace option. The resulting HMAC/signature is
included in the Trace Signature field.
2. Subsequent nodes will update the Trace Signature field by
creating a signature/HMAC of data where the data is [Trace
Signature || its node_data_list[x] hash] with its symmetric key.
3. The Validator will iteratively recreate the Trace Signature over
the node data trace fields collected and matches the Trace
Signature field to validate the trace data integrity.
4.3.1. Overhead consideration for Method 3
Much like method 2, the Trace Signature would consume 16 or 32 bytes
- though with method 3, the Trace Signature is only carried once for
the entire packet.
4.4. Method 4: Dynamic symmetric keys based signing of trace data
This method builds on top of Method 3 leverages Post-quantum Secure
Pre-shared key distribution for deriving a dynamic symmetric key for
every packet or a set of packets. The method utilizes the dynamic
keys to provide for replay protection and does not require a seed to
be added to the trace data to protect from replays because a private
key is derived for each packet. The method relies on a local service
that generates common Key/KeyID pairs for the participating Node and
Validator (see the figure below). This common key generator uses
ratcheting cryptography to generate the next secret while forgetting
about the previous one. A unique ID is paired with each secret
generated. Given the same seed secret as input parameter, two
implementations of the common key generator will generate the exact
same key and associated ID. The common key generator can be queried
for the next key or for a specific key ID.
The figure below illustrates the concept:
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Validator Node
| |
| |
Generate McEliece |
public/private key-pair |
| |
|<---Establ. classic secure connection---------|
| (e.g. TLS) |
|---Send public key over secure connection---->|
| |
| Generate random secret seed
| and encrypt w/ Validator
| public key
| |
|<--Send encrypted seed over secure connection-|
| |
Decrypt secret seed sent from Node |
using Validator's private key |
| |
(-- Common secret seed established between --)
(-- Node and Validator --)
| |
| Generate Node's KeyID pair
| based on common secret seed
| |
| Use Node's key to update Trace Signature field
| in trace option header. Include Node's KeyID
| in the extended node data.
| |
(-- Packet reaches Validator --)
| |
Get Node's key using Node's KeyID |
present in extended node data. |
Validate Trace Signature using Node's key. |
The main steps of method 4 are:
1. Each node will establish a common secret seed establishment using
McEliece [McEliece] with the Validator.
2. Each node will then use the seed to generate a symmetric key per
packet and use it in updating the Trace Signature field in the
IOAM Trace-Option header over its node data hash. The node data
is extended to include the KeyID of the dynamic key generated.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| KeyID [x] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| node data list [x] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3. The Validator will validate the Trace Signature by deducing the
key for each node using the KeyID.
The detailed mechanisms how keys and seeds are exchanged between
nodes are outside the scope of this document.
4.4.1. Overhead consideration for Method 4
Like with method 3, the Trace Signature is only carried once for the
entire packet and could be 32 bytes total. In addition, the KeyID
needs to be added on a per hop basis. For sizing the Key ID, similar
considerations like those for proof-of-transit packet random numbers
apply - i.e. it depends on the packet rates of quickly keys are
consumed. E.g. assuming a packet rate of 100Gbps and a KeyID space
of 64 bits / 8 bytes, the system would need to be re-keyed after 3100
years (see also [I-D.ietf-sfc-proof-of-transit]). If frequent re-
keying is feasible, 32 bits for KeyID might well be feasible.
5. IANA Considerations
This document is to support the IPPM working group to design and
specify a solution for protecting the integrity of IOAM data fields.
It does not include any requests to IANA.
6. Security Considerations
This section will be completed in a future revision of this document.
7. Acknowledgements
The authors would like to thank Santhosh N, Rakesh Kandula, Saiprasad
Muchala, Greg Mirsky, Benjamin Kaduk and Martin Duke for their
comments and advice.
8. References
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8.1. 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>.
[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>.
8.2. Informative References
[BLS] "BLS (Boneh-Lynn-Shacham) digital signature", 2021,
<https://en.wikipedia.org/wiki/BLS_digital_signature>.
[EdDSA25519]
"Edwards-curve Digital Signature Algorithm (EdDSA)", 2021,
<https://en.wikipedia.org/wiki/EdDSA#Ed25519>.
[I-D.brockners-ippm-ioam-geneve]
Brockners, F., Bhandari, S., Govindan, V., Pignataro, C.,
Nainar, N., Gredler, H., Leddy, J., Youell, S., Mizrahi,
T., Lapukhov, P., Gafni, B., Kfir, A., and M. Spiegel,
"Geneve encapsulation for In-situ OAM Data", draft-
brockners-ippm-ioam-geneve-05 (work in progress), November
2020.
[I-D.ietf-detnet-security]
Grossman, E., Mizrahi, T., and A. Hacker, "Deterministic
Networking (DetNet) Security Considerations", draft-ietf-
detnet-security-13 (work in progress), December 2020.
[I-D.ietf-ippm-ioam-data]
Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
for In-situ OAM", draft-ietf-ippm-ioam-data-11 (work in
progress), November 2020.
[I-D.ietf-ippm-ioam-ipv6-options]
Bhandari, S., Brockners, F., Pignataro, C., Gredler, H.,
Leddy, J., Youell, S., Mizrahi, T., Kfir, A., Gafni, B.,
Lapukhov, P., Spiegel, M., Krishnan, S., Asati, R., and M.
Smith, "In-situ OAM IPv6 Options", draft-ietf-ippm-ioam-
ipv6-options-04 (work in progress), November 2020.
Brockners, et al. Expires July 29, 2021 [Page 15]
Internet-Draft IOAM Data Fields Integrity January 2021
[I-D.ietf-nvo3-geneve]
Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic
Network Virtualization Encapsulation", draft-ietf-
nvo3-geneve-16 (work in progress), March 2020.
[I-D.ietf-sfc-ioam-nsh]
Brockners, F. and S. Bhandari, "Network Service Header
(NSH) Encapsulation for In-situ OAM (IOAM) Data", draft-
ietf-sfc-ioam-nsh-05 (work in progress), December 2020.
[I-D.ietf-sfc-proof-of-transit]
Brockners, F., Bhandari, S., Mizrahi, T., Dara, S., and S.
Youell, "Proof of Transit", draft-ietf-sfc-proof-of-
transit-08 (work in progress), November 2020.
[McEliece]
McEliece, R., "A Public-Key Cryptosystem Based on
Algebraic Coding Theory", 1978,
<https://ipnpr.jpl.nasa.gov/
progress_report2/42-44/44N.PDF>.
[RFC7276] Mizrahi, T., Sprecher, N., Bellagamba, E., and Y.
Weingarten, "An Overview of Operations, Administration,
and Maintenance (OAM) Tools", RFC 7276,
DOI 10.17487/RFC7276, June 2014,
<https://www.rfc-editor.org/info/rfc7276>.
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384,
October 2014, <https://www.rfc-editor.org/info/rfc7384>.
[RFC7799] Morton, A., "Active and Passive Metrics and Methods (with
Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
May 2016, <https://www.rfc-editor.org/info/rfc7799>.
[RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
"Network Service Header (NSH)", RFC 8300,
DOI 10.17487/RFC8300, January 2018,
<https://www.rfc-editor.org/info/rfc8300>.
Authors' Addresses
Brockners, et al. Expires July 29, 2021 [Page 16]
Internet-Draft IOAM Data Fields Integrity January 2021
Frank Brockners
Cisco Systems, Inc.
Hansaallee 249, 3rd Floor
DUESSELDORF, NORDRHEIN-WESTFALEN 40549
Germany
Email: fbrockne@cisco.com
Shwetha Bhandari
Thoughtspot
3rd Floor, Indiqube Orion, 24th Main Rd, Garden Layout, HSR Layout
Bangalore, KARNATAKA 560 102
India
Email: shwetha.bhandari@thoughtspot.com
Tal Mizrahi
Huawei
8-2 Matam
Haifa 3190501
Israel
Email: tal.mizrahi.phd@gmail.com
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