Characterizing OAM: Guidelines for Characterizing the Term "OAM"

Internet Engineering Task Force (IETF)                      C. Pignataro
Request for Comments: 10014                         Blue Fern Consulting
BCP: 161                                                       A. Farrel
Updates: 6291                                         Old Dog Consulting
Category: Best Current Practice                               T. Mizrahi
ISSN: 2070-1721                                                   Huawei
                                                               June 2026


              Guidelines for Characterizing the Term "OAM"

Abstract

   As the IETF continues to produce and standardize different
   Operations, Administration, and Maintenance (OAM) protocols and
   technologies, various qualifiers and modifiers are prepended to the
   OAM abbreviation.  While, at first glance, the most used qualifiers
   appear to be well understood, the same qualifier may be interpreted
   differently in different contexts.  A case in point is the qualifiers
   "in-band" and "out-of-band", which have their origins in the radio
   lexicon, and which have been extrapolated into other communication
   networks.  This document recommends not to use these two terms when
   referring to OAM.

   This document considers some common qualifiers and modifiers that are
   prepended, within the context of packet networks, to the OAM
   abbreviation and lays out guidelines for their use in IETF documents.

   This document extends RFC 6291 by adding to the guidelines for the
   use of the term "OAM" with qualifiers.  It does not modify any part
   of RFC 6291.

Status of This Memo

   This memo documents an Internet Best Current Practice.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   BCPs is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc10014.

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
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   Trust Legal Provisions and are provided without warranty as described
   in the Revised BSD License.

Table of Contents

   1.  Introduction
     1.1.  Requirements Language
   2.  In-Band and Out-of-Band OAM
   3.  Terminology and Guidance
     3.1.  Recommendation
     3.2.  Active, Passive, and Hybrid OAM
     3.3.  Path-Congruent OAM
     3.4.  Packet-Forwarding-Treatment OAM
     3.5.  Using Multiple Criteria
     3.6.  Summary of Terms
     3.7.  Applicability and Conformance Statement
   4.  Security Considerations
   5.  IANA Considerations
   6.  References
     6.1.  Normative References
     6.2.  Informative References
   Appendix A.  Examples of the Use of the Term "In-Band"
   Acknowledgements
   Authors' Addresses

1.  Introduction

   It is not uncommon for historical and popular terms to have nuances
   in how they are interpreted or understood.  This was, for example,
   the case with the abbreviation for Operations, Administration, and
   Maintenance, "OAM", and [RFC6291] provides guidelines for its use as
   well as definitions of its constituent parts.

   Characterizations or qualifiers for "OAM" within packet networks
   often encounter similar problems of interpretation, such as with the
   adjective phrases "in-band" and "out-of-band" (Section 2).  This
   document considers some common qualifiers and modifiers that are
   prepended to the OAM abbreviation, and it lays out guidelines for
   their use in future IETF work to achieve consistent and unambiguous
   characterization (Section 3).

   This document focuses on qualifiers for the term "OAM", not the
   definition of "OAM" or "OAM protocols".  Readers should refer to
   [RFC6291] for an overview of OAM scope.  This document does not
   extend or restrict that scope.  The term "OAM protocols" refers to
   protocols used for implementing measurement or diagnostic OAM
   functions as defined in Section 2.2.3 of [RFC7276].

   While this document introduces new terminology, it does not update or
   change the meaning of terminology found in existing RFCs.

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

2.  In-Band and Out-of-Band OAM

   Historically, the terms "in-band" and "out-of-band" were used
   extensively in radio communications as well as in telephony signaling
   [RFC4733].  In both these cases, there is an actual "Band" (i.e., a
   "Channel" or "Frequency") to be within or outside.

   While those terms, useful in their simplicity, continued to be
   broadly used to mean "within something" and "outside something", a
   challenge is presented for IP communications and packet-switched
   networks (PSNs), which do not have a "band" per se, and, in fact,
   have multiple "somethings" that OAM traffic can be carried within or
   outside.  A frequently encountered case is the use of "in-band" to
   mean either in-data-packet or on-path.

   There are many examples of "in-band OAM" and "out-of-band OAM" in
   RFCs.  For instance, the term "in-band" appears in both Virtual
   Circuit Connectivity Verification (VCCV) [RFC5085] and OAM for
   Deterministic Networking (DetNet) [RFC9551].  While the context in
   each of these documents is clear, the term carries different meanings
   in each case.  These two examples, as well as other examples of uses
   of the term "in-band" in other documents are described in Appendix A.

   Generally speaking, within the IETF, the terms "in-band" and "out-of-
   band" cannot be reliably understood consistently and unambiguously.
   Context-specific definitions of these terms are inconsistent and
   therefore cannot be generalized.  More importantly, the terms are not
   self-defining to any further extent and cannot be understood by
   someone exposed to them for the first time, since there is no "band"
   in IP.

   While interpreting existing documents, it is important to understand
   the semantics of what the term "band" refers to, and to be more
   explicit if those documents are updated.  This document does not
   change the meaning of any terms in any prior RFCs.

   The applicability of the guidance in Section 3.1 is provided in
   Section 3.7.

3.  Terminology and Guidance

3.1.  Recommendation

   This document recommends avoiding the terms "in-band" and "out-of-
   band" when referring to OAM.  Instead, it encourages the use of more
   fine-grained and descriptive terminology.  The document also presents
   alternative terms and definitions for use in future IETF documents
   that discuss OAM (including a reference to this document), without
   precluding the use of other precise, descriptive terms that do not
   rely on the "-band" convention.

   The terminology presented in this section classifies OAM according to
   three criteria: whether it operates in an active, passive, or hybrid
   mode (Section 3.2); whether it follows the same path as data traffic
   (Section 3.3); and whether it receives the same treatment as data
   traffic (Section 3.4).

3.2.  Active, Passive, and Hybrid OAM

   [RFC7799] provides clear definitions for active and passive
   performance assessment, enabling the construction of metrics and
   methods to be described as either "Active" or "Passive".  Even though
   [RFC7799] does not explicitly use these terms as modifiers of "OAM",
   they are widely used in practice and are included here for clarity.
   The terms "Active", "Passive" and "Hybrid", as described below, are
   consistent with [RFC7799].  This document does not update or change
   the terms of [RFC7799].

   Active OAM:
      Uses dedicated OAM packets.

   Passive OAM:
      Relies on the observation of one or more existing data packet
      streams and does not use dedicated OAM packets and does not modify
      data packets.

   Hybrid OAM:
      Uses a combination of Active Methods and Passive Methods, which
      may include augmentation or modification of the stream of
      interest.  [RFC7799] makes a distinction between Hybrid Type I,
      referring to a single stream of interest, and Hybrid Type II,
      referring to two or more streams of interest.

   This document defines the term "In-Data-Packet OAM" as a more
   specific and narrowly scoped instance within the broader category of
   Hybrid OAM.  This new term allows for a more fine-grained
   classification of OAM mechanisms, as the broad category of Hybrid OAM
   includes a diverse set of possible OAM methods.

   In-Data-Packet OAM:
      OAM-related information is carried in the packets that also carry
      the data traffic.  This is a specific case of Hybrid OAM.  It was
      sometimes referred to as "in-band".

   Note that In-Data-Packet OAM is a specific case of Hybrid Type I, as
   it is applied to a single stream of interest.

   The following examples illustrate the terms Active, Passive, Hybrid,
   and In-Data-Packet OAM:

   *  The MPLS echo request/reply messages [RFC8029] are an example of
      "Active OAM", since they are described as "An MPLS echo request/
      reply is a (possibly MPLS-labeled) IPv4 or IPv6 UDP packet".

   *  Monitoring a packet stream by maintaining counters for the packets
      within the stream is an example of "Passive OAM".

   *  An example of "Hybrid Type I OAM" that is also "In-Data-Packet
      OAM", is an IOAM (In Situ OAM) [RFC9197] trace option that is
      incorporated into data packets of a single stream of interest.
      According to [RFC9197], 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 being sent within packets
      specifically dedicated to OAM.'

   *  Another example of "Hybrid Type I OAM" that is also "In-Data-
      Packet OAM" is Alternate Marking [RFC9341], when applied to data
      packets of a single stream.  In this case, a small number of bits
      in the packet header is used for marking a subset of packets in a
      flow.

   *  An example of "Hybrid Type I OAM" that is not classified as "In-
      Data-Packet OAM" is Direct Loss Measurement [RFC6374], in which
      user packets are not modified by the protocol.  Instead, OAM
      packets are used for carrying information about observed network
      characteristics -- namely, user packet counter values that allow
      for packet loss computation.

   *  Another example of "Hybrid Type I OAM" that is not "In-Data-Packet
      OAM" is the case where a packet stream is (actively) generated
      while an existing stream of interest is (passively) observed.
      This example was introduced in [RFC7799] as a Hybrid Type I
      method.  Extending this example, if the packets of the active
      stream include an IOAM trace option, the method is characterized
      by the more general term, Hybrid Type I.

3.3.  Path-Congruent OAM

   Path-Congruent OAM:
      The OAM information follows the exact same forwarding path as the
      observed data traffic.

   Non-Path-Congruent OAM:
      The OAM information is not guaranteed to follow the exact same
      forwarding path as the observed data traffic.

   In this document, the term "path-congruent packets" describes packets
   that follow the exact same path (i.e., traverse the same nodes and
   links) within a network.  Note that this definition does not describe
   how the packets are treated in queues within the nodes on the path.

   An example of "Path-Congruent OAM" is the Virtual Circuit
   Connectivity Verification (VCCV) Type 1 (Section 5.1.1 of [RFC5085]),
   which was also referred to as "In-Band VCCV".  The term "congruent"
   also appears in Section 2 of [RFC6669] in the context of path
   sharing.

3.4.  Packet-Forwarding-Treatment OAM

   Equal-Forwarding-Treatment OAM:
      The OAM packets receive the same forwarding treatment (e.g., QoS)
      as user data packets.

   Different-Forwarding-Treatment OAM:
      The OAM packets might receive different forwarding treatment
      (e.g., QoS) than user data packets.

   The motivation for Equal-Forwarding-Treatment OAM lies in the desire
   to ensure that OAM packets experience the same network conditions as
   the user data they are intended to monitor.  This includes not only
   traversing the same topological path but also receiving identical
   Quality of Service (QoS) treatment, such as queuing, scheduling, and
   traffic shaping.  When both topological and forwarding treatment
   equivalence are achieved, the OAM packets are said to exhibit fate-
   sharing [RFC7276] with the data traffic.  Fate-sharing ensures that
   any impairments or anomalies affecting the user traffic are also
   reflected in the behavior of the OAM packets, thereby making the
   results of the OAM observations more operationally meaningful and
   actionable.  Without such equivalence, discrepancies in treatment
   could lead to misleading measurements or diagnostics, and even
   inadequate corrective actions, reducing the utility of the OAM
   mechanism for performance monitoring, fault detection, and fault
   mitigation.

   An example of "Equal-Forwarding-Treatment OAM" is presented in
   [RFC9551] in the context of Deterministic Networking (DetNet) OAM:
   "it traverses the same set of links and interfaces receiving the same
   QoS and Packet Replication, Elimination, and Ordering Functions
   (PREOF) treatment as the monitored DetNet flow".  (The property of
   "Equal-Forwarding-Treatment" is referred to in [RFC9551] as "In-band
   OAM".)

3.5.  Using Multiple Criteria

   OAM protocols and tools can be classified according to the three
   criteria that were described in the previous sections.  However, not
   all criteria are applicable to all OAM protocols, and not all
   combinations are necessarily possible.  For example:

   *  Passive OAM relies solely on observing existing data traffic and
      does not generate dedicated OAM packets.  As such, the path
      congruence and forwarding treatment criteria are not relevant,
      because no dedicated OAM packets are exchanged between the
      measurement points.

   *  Non-Path-Congruent OAM, by nature, cannot be Equal-Forwarding-
      Treatment.

   When defining a new OAM mechanism or analyzing an existing one, it is
   recommended to explicitly consider which of these criteria are
   applicable and to describe the mechanism accordingly.  As a first
   step, all OAM mechanisms can be classified according to the first
   criterion, as Active, Passive, or Hybrid/In-Data-Packet.  Further
   classification according to the other two criteria should be
   considered on a case-by-case basis.

   A few examples of OAM classification according to the three criteria
   are presented below:

   *  IP Ping, which uses ICMP Echo messages, can be classified as
      Active OAM.  Since it is not guaranteed to follow the same path or
      receive the same treatment as user data packets, it is classified
      as Non-Path-Congruent and, consequently, as Different-Forwarding-
      Treatment.

   *  When an IOAM trace option [RFC9197] is incorporated in data
      packets, it can be classified as In-Data-Packet, Path-Congruent,
      and Equal-Forwarding-Treatment.

   *  VCCV [RFC5085], as discussed above, is classified as Active, Path-
      Congruent, and Different-Forwarding-Treatment.

   *  MPLS Inferred Loss Measurement (ILM) (Section 3 of [RFC6374]) uses
      specially generated test messages and therefore can be classified
      as Active.  It is also Path-Congruent and can be deployed either
      as Equal- or Different-Forwarding-Treatment OAM.  MPLS Direct Loss
      Measurement (DLM) (Section 3 of [RFC6374]) uses OAM messages that
      carry counters that count user data traffic.  Hence, it is
      classified as Hybrid Type I OAM, and as in the Inferred Loss
      Measurement, it is Path-Congruent and can be either Equal- or
      Different-Forwarding-Treatment OAM.

   In measurement protocols, accurate results depend on Path-Congruence
   and Equal-Forwarding-Treatment.  In contrast, these properties are
   not always required in other OAM protocols.  For example,
   Bidirectional Forwarding Detection (BFD) [RFC5880] control packets
   are often sent with the highest priority, which means they do not
   adhere to the Equal-Forwarding-Treatment property.

   This multidimensional classification enables a more precise and
   consistent understanding of OAM mechanisms.

3.6.  Summary of Terms

   This section summarizes the terminology.

   Active OAM:
      Uses dedicated OAM packets.

   Passive OAM:
      Relies on the observation of one or more existing data packet
      streams and does not use dedicated OAM packets and does not modify
      data packets.

   Hybrid OAM:
      Uses a combination of Active Methods and Passive Methods, which
      may include augmentation or modification of the stream of
      interest.  [RFC7799] makes a distinction between Hybrid Type I,
      referring to a single stream of interest, and Hybrid Type II,
      referring to two or more streams of interest.

   In-Data-Packet OAM:
      OAM-related information is carried in the packets that also carry
      the data traffic.  This is a specific case of Hybrid OAM.  It was
      sometimes referred to as "in-band".

   Path-Congruent OAM:
      The OAM information follows the exact same forwarding path as the
      observed data traffic.

   Non-Path-Congruent OAM:
      The OAM information is not guaranteed to follow the exact same
      forwarding path as the observed data traffic.

   Equal-Forwarding-Treatment OAM:
      The OAM packets receive the same forwarding treatment (e.g., QoS)
      as user data packets.

   Different-Forwarding-Treatment OAM:
      The OAM packets might receive different forwarding treatment
      (e.g., QoS) than user data packets.

3.7.  Applicability and Conformance Statement

   The definitions here SHOULD be used by IETF documents qualifying the
   term "OAM".  IETF documents that explicitly want to create different
   characterizations beyond the definitions of the terms in this
   document, can introduce such terms provided they are different from
   the ones defined in this document for clarity's sake.  See also
   Section 3.1.

   Authors who follow the terms as defined in this document SHOULD
   incorporate the following in the document (typically in the
   terminology section):

   <BEGIN TEMPLATE TEXT>
      OAM terms [INSERT TERMS] are to be interpreted as described in
      [RFC10014].
   <END TEMPLATE TEXT>

4.  Security Considerations

   Security is improved when terms are used with precision, and their
   definitions are unambiguous.

5.  IANA Considerations

   This document has no IANA actions.

6.  References

6.1.  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>.

   [RFC6291]  Andersson, L., van Helvoort, H., Bonica, R., Romascanu,
              D., and S. Mansfield, "Guidelines for the Use of the "OAM"
              Acronym in the IETF", BCP 161, RFC 6291,
              DOI 10.17487/RFC6291, June 2011,
              <https://www.rfc-editor.org/info/rfc6291>.

   [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>.

   [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>.

6.2.  Informative References

   [P4-INT-2.1]
              The P4.org Applications Working Group, "In-band Network
              Telemetry (INT) Dataplane Specification", Version 2.1, 11
              November 2020, <https://p4.org/wp-
              content/uploads/sites/53/p4-spec/docs/INT_v2_1.pdf>.

   [RFC4733]  Schulzrinne, H. and T. Taylor, "RTP Payload for DTMF
              Digits, Telephony Tones, and Telephony Signals", RFC 4733,
              DOI 10.17487/RFC4733, December 2006,
              <https://www.rfc-editor.org/info/rfc4733>.

   [RFC5085]  Nadeau, T., Ed. and C. Pignataro, Ed., "Pseudowire Virtual
              Circuit Connectivity Verification (VCCV): A Control
              Channel for Pseudowires", RFC 5085, DOI 10.17487/RFC5085,
              December 2007, <https://www.rfc-editor.org/info/rfc5085>.

   [RFC5880]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
              <https://www.rfc-editor.org/info/rfc5880>.

   [RFC6374]  Frost, D. and S. Bryant, "Packet Loss and Delay
              Measurement for MPLS Networks", RFC 6374,
              DOI 10.17487/RFC6374, September 2011,
              <https://www.rfc-editor.org/info/rfc6374>.

   [RFC6669]  Sprecher, N. and L. Fang, "An Overview of the Operations,
              Administration, and Maintenance (OAM) Toolset for MPLS-
              Based Transport Networks", RFC 6669, DOI 10.17487/RFC6669,
              July 2012, <https://www.rfc-editor.org/info/rfc6669>.

   [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>.

   [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>.

   [RFC9197]  Brockners, F., Ed., Bhandari, S., Ed., and T. Mizrahi,
              Ed., "Data Fields for In Situ Operations, Administration,
              and Maintenance (IOAM)", RFC 9197, DOI 10.17487/RFC9197,
              May 2022, <https://www.rfc-editor.org/info/rfc9197>.

   [RFC9232]  Song, H., Qin, F., Martinez-Julia, P., Ciavaglia, L., and
              A. Wang, "Network Telemetry Framework", RFC 9232,
              DOI 10.17487/RFC9232, May 2022,
              <https://www.rfc-editor.org/info/rfc9232>.

   [RFC9341]  Fioccola, G., Ed., Cociglio, M., Mirsky, G., Mizrahi, T.,
              and T. Zhou, "Alternate-Marking Method", RFC 9341,
              DOI 10.17487/RFC9341, December 2022,
              <https://www.rfc-editor.org/info/rfc9341>.

   [RFC9551]  Mirsky, G., Theoleyre, F., Papadopoulos, G., Bernardos,
              CJ., Varga, B., and J. Farkas, "Framework of Operations,
              Administration, and Maintenance (OAM) for Deterministic
              Networking (DetNet)", RFC 9551, DOI 10.17487/RFC9551,
              March 2024, <https://www.rfc-editor.org/info/rfc9551>.

Appendix A.  Examples of the Use of the Term "In-Band"

   This appendix provides a few examples of the use of the term "in-
   band".  These are intended to highlight the varying interpretations
   of the term across different contexts, which led to the guidelines in
   this document.

   In-Data-Packet OAM was in some cases referred to as "in-band".
   Initially, "In situ OAM" [RFC9197] was also referred to as "In-band
   OAM", but was renamed due to the overloaded meaning of "In-band OAM".
   Further, [RFC9232] also intertwines the terms "in-band" with "in
   situ".  Other similar documents, including [P4-INT-2.1], still use
   variations of "in-band", "in band", or "inband".

   Path-Congruent OAM was sometimes referred to as "in-band".  As
   described in [RFC5085], "The VCCV message travels in-band with the
   Session and follows the exact same path as the user data for the
   session".  The term "in-band" is also used in Section 2 of [RFC6669]
   with the same meaning.  Non-Path-Congruent OAM was referred to in
   [RFC5085] as "Out-of-Band".

   The property of "Equal-Forwarding-Treatment" is referred to in
   [RFC9551] as "In-band OAM".  Similarly, the property of "Different-
   Forwarding-Treatment OAM" can be found in the following definition in
   [RFC9551]: "Out-of-band OAM: an active OAM method whose path through
   the DetNet domain may not be topologically identical to the path of
   the monitored DetNet flow, its test packets may receive different QoS
   and/or PREOF treatment, or both."

Acknowledgements

   The creation of this document was triggered when observing one of
   many on-mailing-list discussions of what these terms mean, and how to
   abbreviate them.  Participants on that mail thread include,
   alphabetically: Adrian Farrel, Alexander Vainshtein, Florian Kauer,
   Frank Brockners, Greg Mirsky, Italo Busi, Loa Andersson, Med
   Boucadair, Michael Richardson, Quan Xiong, Stewart Bryant, Tom Petch,
   Eduard Vasilenko, and Xiao Min.

   The authors wish to thank, chronologically, Hesham Elbakoury, Michael
   Richardson, Stewart Bryant, Greg Mirsky, Med Boucadair, Loa
   Andersson, Thomas Graf, Alex Huang-Feng, Xiao Min, Dhruv Dhody, Henk
   Birkholz, Tom Petch, Roni Even, Tim Chown, Marcus Ihlar, Med
   Boucadair, Benoit Claise, Chongfeng Xie, Robert Sparks, Kyle Rose,
   Mach Chen, Roman Danyliw, Gorry Fairhurst, Éric Vyncke, Andy Newton,
   Deb Cooley, Ketan Talaulikar, and Gunter Van de Velde for their
   thorough review and useful feedback comments that greatly improved
   this document.

Authors' Addresses

   Carlos Pignataro
   Blue Fern Consulting
   United States of America / Spain
   Email: carlos@bluefern.consulting


   Adrian Farrel
   Old Dog Consulting
   United Kingdom
   Email: adrian@olddog.co.uk


   Tal Mizrahi
   Huawei
   Matam
   Haifa 3190501
   Israel
   Email: tal.mizrahi.phd@gmail.com