draft-ietf-ippm-more-twamp-02.txt   rfc5618.txt 
Network Working Group A. Morton Network Working Group A. Morton
Internet-Draft AT&T Labs Request for Comments: 5618 AT&T Labs
Updates: 5357 (if approved) K. Hedayat Updates: 5357 K. Hedayat
Intended status: Standards Track EXFO Category: Standards Track EXFO
Expires: November 21, 2009 May 20, 2009 August 2009
More Features for the Two-Way Active Measurement Protocol - TWAMP
draft-ietf-ippm-more-twamp-02
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79. This document may contain material
from IETF Documents or IETF Contributions published or made publicly
available before November 10, 2008. The person(s) controlling the
copyright in some of this material may not have granted the IETF
Trust the right to allow modifications of such material outside the
IETF Standards Process. Without obtaining an adequate license from
the person(s) controlling the copyright in such materials, this
document may not be modified outside the IETF Standards Process, and
derivative works of it may not be created outside the IETF Standards
Process, except to format it for publication as an RFC or to
translate it into languages other than English.
Internet-Drafts are working documents of the Internet Engineering Mixed Security Mode for the Two-Way Active Measurement Protocol (TWAMP)
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months Abstract
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at This memo describes a simple extension to TWAMP (the Two-Way Active
http://www.ietf.org/ietf/1id-abstracts.txt. Measurement Protocol). The extension adds the option to use
different security modes in the TWAMP-Control and TWAMP-Test
protocols simultaneously. The memo also describes a new IANA
registry for additional features, called the TWAMP Modes registry.
The list of Internet-Draft Shadow Directories can be accessed at Status of This Memo
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on November 21, 2009. This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice Copyright Notice
Copyright (c) 2009 IETF Trust and the persons identified as the Copyright (c) 2009 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents in effect on the date of Provisions Relating to IETF Documents in effect on the date of
publication of this document (http://trustee.ietf.org/license-info). publication of this document (http://trustee.ietf.org/license-info).
Please review these documents carefully, as they describe your rights Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. and restrictions with respect to this document.
Abstract This document may contain material from IETF Documents or IETF
Contributions published or made publicly available before November
This memo describes a simple extension to TWAMP - the Two-Way Active 10, 2008. The person(s) controlling the copyright in some of this
Measurement Protocol. The extension adds the option to use different material may not have granted the IETF Trust the right to allow
security modes in the TWAMP-Control and TWAMP-Test protocols modifications of such material outside the IETF Standards Process.
simultaneously. The memo also requests that IANA establish a Without obtaining an adequate license from the person(s) controlling
registry for additional new features, called the TWAMP-Modes the copyright in such materials, this document may not be modified
registry. outside the IETF Standards Process, and derivative works of it may
not be created outside the IETF Standards Process, except to format
Requirements Language it for publication as an RFC or to translate it into languages other
than English.
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 RFC 2119 [RFC2119].
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction ....................................................2
2. Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Requirements Language ......................................3
3. TWAMP Control Extensions . . . . . . . . . . . . . . . . . . . 4 2. Purpose and Scope ...............................................3
3.1. Extended Control Connection Setup . . . . . . . . . . . . . 5 3. TWAMP Control Extensions ........................................3
4. Extended TWAMP Test . . . . . . . . . . . . . . . . . . . . . . 6 3.1. Extended Control Connection Setup ..........................3
4.1. Sender Behavior . . . . . . . . . . . . . . . . . . . . . . 7 4. Extended TWAMP Test .............................................5
4.1.1. Packet Timings . . . . . . . . . . . . . . . . . . . . 7 4.1. Sender Behavior ............................................5
4.1.2. Packet Format and Content . . . . . . . . . . . . . . . 7 4.1.1. Packet Timings ......................................5
4.2. Reflector Behavior . . . . . . . . . . . . . . . . . . . . 7 4.1.2. Packet Format and Content ...........................5
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 7 4.2. Reflector Behavior .........................................6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations .........................................6
6.1. Registry Specification . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations .............................................6
6.2. Registry Management . . . . . . . . . . . . . . . . . . . . 8 6.1. Registry Specification .....................................6
6.3. Experimental Numbers . . . . . . . . . . . . . . . . . . . 8 6.2. Registry Management ........................................6
6.4. Initial Registry Contents . . . . . . . . . . . . . . . . . 8 6.3. Experimental Numbers .......................................7
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 6.4. Initial Registry Contents ..................................7
8. Normative References . . . . . . . . . . . . . . . . . . . . . 9 7. Acknowledgements ................................................7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9 8. Normative References ............................................7
1. Introduction 1. Introduction
The Two-Way Active Measurement Protocol, TWAMP [RFC5357] is an The Two-Way Active Measurement Protocol (TWAMP) [RFC5357] is an
extension of the One-way Active Measurement Protocol, OWAMP extension of the One-Way Active Measurement Protocol (OWAMP)
[RFC4656]. The TWAMP specification gathered wide review as it [RFC4656]. The TWAMP specification gathered wide review as it
approached completion, and the by-products were several approached completion, and the by-products were several
recommendations for new features in TWAMP. There is a growing number recommendations for new features in TWAMP. There is a growing number
TWAMP implementations at present, and wide-spread usage is expected. of TWAMP implementations at present, and widespread usage is
There are even devices that are designed to test implementations for expected. There are even devices that are designed to test
protocol compliance. implementations for protocol compliance.
This memo describes a simple extension for TWAMP, the option to use This memo describes a simple extension for TWAMP: the option to use
different security modes in the TWAMP-Control and TWAMP-Test different security modes in the TWAMP-Control and TWAMP-Test
protocols (mixed security mode). It also requests that IANA protocols (mixed security mode). It also describes a new IANA
establish a registry for additional new features, called the TWAMP- registry for additional features, called the TWAMP Modes registry.
Modes registry.
When the Server and Control-Client have agreed to use the mixed When the Server and Control-Client have agreed to use the mixed
security mode during control connection setup, then the Control- security mode during control connection setup, then the Control-
Client, the Server, the Session-Sender and the Session-Reflector MUST Client, the Server, the Session-Sender, and the Session-Reflector
all conform to the requirements of this mode as described in sections MUST all conform to the requirements of this mode as described in
3, 4, and 5. Sections 3, 4, and 5.
This memo updates [RFC5357]. This memo updates [RFC5357].
1.1. Requirements Language
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 RFC 2119 [RFC2119].
2. Purpose and Scope 2. Purpose and Scope
The purpose of this memo is to describe and specify an extension for The purpose of this memo is to describe and specify an extension for
TWAMP [RFC5357], and request the establishment of a registry for TWAMP [RFC5357], and to request the establishment of a registry for
future TWAMP extensions. future TWAMP extensions.
The scope of the memo is limited to specifications of the following: The scope of the memo is limited to specifications of the following:
o Extension of the modes of operation through assignment of one new o Extension of the modes of operation through assignment of one new
value in the Mode field (see section 3.1 of [RFC4656]), while value in the Modes field (see Section 3.1 of [RFC4656]), while
retaining backward compatibility with TWAMP [RFC5357] retaining backward compatibility with TWAMP [RFC5357]
implementations. This value adds the OPTIONAL ability to use implementations. This value adds the OPTIONAL ability to use
different security modes in the TWAMP-Control and TWAMP-Test different security modes in the TWAMP-Control and TWAMP-Test
protocols. The motivation for this extension is to permit the low protocols. The motivation for this extension is to permit the
packet rate TWAMP-Control protocol to utilize a stronger mode of low-packet-rate TWAMP-Control protocol to utilize a stronger mode
integrity protection than that used in the TWAMP-Test protocol. of integrity protection than that used in the TWAMP-Test protocol.
3. TWAMP Control Extensions 3. TWAMP Control Extensions
TWAMP-Control protocol is a derivative of the OWAMP-Control protocol, The TWAMP-Control protocol is a derivative of the OWAMP-Control
and coordinates a two-way measurement capability. All TWAMP Control protocol, and coordinates a two-way measurement capability. All
messages are similar in format and follow similar guidelines to those TWAMP-Control messages are similar in format and follow similar
defined in section 3 of [RFC4656] with the exceptions described in guidelines to those defined in Section 3 of [RFC4656], with the
TWAMP [RFC5357], and in the following sections. exceptions described in TWAMP [RFC5357] and in the following
sections.
All OWAMP-Control messages apply to TWAMP-Control, except for the All OWAMP-Control messages apply to TWAMP-Control, except for the
Fetch Session command. Fetch-Session command.
3.1. Extended Control Connection Setup 3.1. Extended Control Connection Setup
TWAMP-Control connection establishment follows the same procedure TWAMP-Control connection establishment follows the same procedure
defined in section 3.1 of [RFC4656]. This extended mode assigns one defined in Section 3.1 of [RFC4656]. This extended mode assigns one
new bit position (and value) to allow the Test protocol security mode new bit position (and value) to allow the Test protocol security mode
to operate in Unauthenticated mode, while the Control protocol to operate in Unauthenticated mode, while the Control protocol
operates in Encrypted mode. With this extension, the complete set of operates in Encrypted mode. With this extension, the complete set of
TWAMP Mode values are as follows: TWAMP Mode values are as follows:
Value Description Reference/Explanation Value Description Reference/Explanation
0 Reserved 0 Reserved
1 Unauthenticated RFC4656, Section 3.1 1 Unauthenticated RFC4656, Section 3.1
2 Authenticated RFC4656, Section 3.1 2 Authenticated RFC4656, Section 3.1
4 Encrypted RFC4656, Section 3.1 4 Encrypted RFC4656, Section 3.1
8 Unauth. TEST protocol, new bit position (3) 8 Unauth. TEST protocol, new bit position (3)
Encrypted CONTROL Encrypted CONTROL
In the original OWAMP and TWAMP Modes field, setting bit position 0, In the original OWAMP and TWAMP Modes field, setting bit position 0,
1 or 2 indicated the security mode of the Control protocol, and the 1, or 2 indicated the security mode of the Control protocol, and the
Test protocol inherited the same mode (see section 4 of [RFC4656]). Test protocol inherited the same mode (see Section 4 of [RFC4656]).
In this extension to TWAMP, when the Control-Client sets Modes Field In this extension to TWAMP, when the Control-Client sets Modes Field
bit position 3, it SHALL discontinue the inheritance of the security bit position 3, it SHALL discontinue the inheritance of the security
mode in the Test protocol, and each protocol's mode SHALL be as mode in the Test protocol, and each protocol's mode SHALL be as
specified below. When the desired TWAMP-Test protocol mode is specified below. When the desired TWAMP-Test protocol mode is
identical to the Control Session mode, the corresponding Modes Field identical to the Control Session mode, the corresponding Modes Field
bit (position 0, 1 or 2) SHALL be set by the Control-Client. The bit (position 0, 1, or 2) SHALL be set by the Control-Client. The
table below gives the various combinations of integrity protection table below gives the various combinations of integrity protection
that are permissible in TWAMP (with this extension). The TWAMP- that are permissible in TWAMP (with this extension). The TWAMP-
Control and TWAMP-Test protocols SHALL use the mode in each column Control and TWAMP-Test protocols SHALL use the mode in each column
corresponding to the bit position set in the Modes Field. corresponding to the bit position set in the Modes Field.
-------------------------------------------------------- --------------------------------------------------------
Protocol | Permissible Mode Combinations (Modes bit set) Protocol | Permissible Mode Combinations (Modes bit set)
-------------------------------------------------------- --------------------------------------------------------
Control | Unauth.(0)| Auth. == Encrypted (1,2,3) Control | Unauth.(0)| Auth. == Encrypted (1,2,3)
-------------------------------------------------------- --------------------------------------------------------
skipping to change at page 6, line 24 skipping to change at page 5, line 4
| | Encrypted (2) | | Encrypted (2)
-------------------------------------------------------- --------------------------------------------------------
Note that the TWAMP-Control protocol security measures are identical Note that the TWAMP-Control protocol security measures are identical
in the Authenticated and Encrypted Modes. Therefore, only one new in the Authenticated and Encrypted Modes. Therefore, only one new
bit position (3) is needed to convey the single mixed security mode. bit position (3) is needed to convey the single mixed security mode.
The value of the Modes Field sent by the Server in the Server- The value of the Modes Field sent by the Server in the Server-
Greeting message is the bit-wise OR of the modes (bit positions) that Greeting message is the bit-wise OR of the modes (bit positions) that
it is willing to support during this session. Thus, the last four it is willing to support during this session. Thus, the last four
bits of the Modes 32-bit Field are used. When no other features are bits of the 32-bit Modes Field are used. When no other features are
activated, the first 28 bits MUST be zero. A client conforming to activated, the first 28 bits MUST be zero. A client conforming to
this extension of [RFC5357] MAY ignore the values in the first 28 this extension of [RFC5357] MAY ignore the values in the first 28
bits of the Modes Field, or it MAY support other features that are bits of the Modes Field, or it MAY support other features that are
communicated in these bit positions. communicated in these bit positions.
Other ways in which TWAMP extends OWAMP are described in [RFC5357]. Other ways in which TWAMP extends OWAMP are described in [RFC5357].
4. Extended TWAMP Test 4. Extended TWAMP Test
The TWAMP test protocol is similar to the OWAMP [RFC4656] test The TWAMP-Test protocol is similar to the OWAMP-Test protocol
protocol with the exception that the Session-Reflector transmits test [RFC4656] with the exception that the Session-Reflector transmits
packets to the Session-Sender in response to each test packet it test packets to the Session-Sender in response to each test packet it
receives. TWAMP [RFC5357] defines two different test packet formats, receives. TWAMP [RFC5357] defines two different test packet formats:
one for packets transmitted by the Session-Sender and one for packets one for packets transmitted by the Session-Sender and one for packets
transmitted by the Session-Reflector. As with OWAMP-Test protocol transmitted by the Session-Reflector. As with the OWAMP-Test
there are three security modes that also determine the test packet protocol, there are three security modes that also determine the test
format: unauthenticated, authenticated, and encrypted. This TWAMP packet format: unauthenticated, authenticated, and encrypted. This
extension makes it possible to use TWAMP-Test Unauthenticated mode TWAMP extension makes it possible to use TWAMP-Test Unauthenticated
regardless of the mode used in the TWAMP-Control protocol. mode regardless of the mode used in the TWAMP-Control protocol.
When the Server has identified the ability to support the mixed When the Server has identified the ability to support the mixed
security mode, the Control-Client has selected the mixed security security mode, the Control-Client has selected the mixed security
mode in its Set-Up-Response, and the Server responds with a zero mode in its Set-Up-Response, and the Server has responded with a zero
Accept field in the Server-Start message, these extensions are Accept field in the Server-Start message, these extensions are
REQUIRED. REQUIRED.
4.1. Sender Behavior 4.1. Sender Behavior
This section describes extensions to the behavior of the TWAMP This section describes extensions to the behavior of the TWAMP
Session-Sender. Session-Sender.
4.1.1. Packet Timings 4.1.1. Packet Timings
The Send Schedule is not utilized in TWAMP, and there are no The send schedule is not utilized in TWAMP, and there are no
extensions defined in this memo. extensions defined in this memo.
4.1.2. Packet Format and Content 4.1.2. Packet Format and Content
The Session-Sender packet format and content MUST follow the same The Session-Sender packet format and content MUST follow the same
procedure and guidelines as defined in section 4.1.2 of [RFC4656] and procedure and guidelines as defined in Section 4.1.2 of [RFC4656] and
section 4.1.2 of [RFC5357], with the following exceptions: Section 4.1.2 of [RFC5357], with the following exceptions:
o the Send Schedule is not used, and o the send schedule is not used, and
o the Session-Sender MUST support the mixed security mode o the Session-Sender MUST support the mixed security mode
(Unauthenticated TEST, Encrypted CONTROL, value 8, bit position 3) (Unauthenticated TEST, Encrypted CONTROL, value 8, bit position 3)
defined in section 3.1 of this memo. defined in Section 3.1 of this memo.
4.2. Reflector Behavior 4.2. Reflector Behavior
The TWAMP Session-Reflector is REQUIRED to follow the procedures and The TWAMP Session-Reflector is REQUIRED to follow the procedures and
guidelines in section 4.2 of [RFC5357], with the following guidelines in Section 4.2 of [RFC5357], with the following
extensions: extensions:
o the Session-Reflector MUST support the mixed security mode o the Session-Reflector MUST support the mixed security mode
(Unauthenticated TEST, Encrypted CONTROL, value 8, bit position 3) (Unauthenticated TEST, Encrypted CONTROL, value 8, bit position 3)
defined in section 3.1 of this memo. defined in Section 3.1 of this memo.
5. Security Considerations 5. Security Considerations
The extended mixed-mode of operation permits stronger security/ The extended mixed mode of operation permits stronger security/
integrity protection on the TWAMP-Control protocol while integrity protection on the TWAMP-Control protocol while
simultaneously emphasizing accuracy or efficiency on the TWAMP-Test simultaneously emphasizing accuracy or efficiency on the TWAMP-Test
protocol, thus making it possible to increase overall security when protocol, thus making it possible to increase overall security when
compared to the previous options. compared to the previous options (when resource constraints would
have forced less security for TWAMP-Control and conditions are such
that use of unauthenticated TWAMP-Test is not a significant concern).
The security considerations that apply to any active measurement of The security considerations that apply to any active measurement of
live networks are relevant here as well. See [RFC4656] and live networks are relevant here as well. See [RFC4656] and
[RFC5357]. [RFC5357].
6. IANA Considerations 6. IANA Considerations
This memo adds one security mode bit position/value beyond those in This memo adds one security mode bit position/value beyond those in
the OWAMP-Control specification[RFC4656], and describes behavior when the OWAMP-Control specification [RFC4656], and describes behavior
the new mode is used. This memo requests creation of an IANA when the new mode is used. According to this document, IANA created
registry for the TWAMP Modes field. This field is a recognized a registry for the TWAMP Modes field. This field is a recognized
extension mechanism for TWAMP. extension mechanism for TWAMP.
6.1. Registry Specification 6.1. Registry Specification
IANA is requested to create a TWAMP-Modes registry. TWAMP-Modes are IANA created a TWAMP Modes registry. TWAMP Modes are specified in
specified in TWAMP Server Greeting messages and Set-up Response TWAMP Server Greeting messages and Set-up Response messages
messages consistent with section 3.1 of [RFC4656] and section 3.1 of consistent with Section 3.1 of [RFC4656] and Section 3.1 of
[RFC5357], and extended by this memo. Modes are currently indicated [RFC5357], and extended by this memo. Modes are currently indicated
by setting single bits in the 32-bit Modes Field. However, more by setting single bits in the 32-bit Modes Field. However, more
complex encoding may be used in the future. Thus, this registry can complex encoding may be used in the future. Thus, this registry can
contain a total of 2^32 possible assignments. contain a total of 2^32 possible assignments.
6.2. Registry Management 6.2. Registry Management
Because the TWAMP-Modes registry can contain a maximum of 2^32 Because the TWAMP Modes registry can contain a maximum of 2^32
values, and because TWAMP is an IETF protocol, this registry must be values, and because TWAMP is an IETF protocol, this registry must be
updated only by "IETF Review" as specified in [RFC5226](an RFC updated only by "IETF Review" as specified in [RFC5226](an RFC
documenting registry use that is approved by the IESG). For the documenting registry use that is approved by the IESG). For the
TWAMP-Modes registry, we expect that new features will be assigned TWAMP Modes registry, we expect that new features will be assigned
using monotonically increasing single bit positions and in the range using monotonically increasing single bit positions and in the range
[0-31], unless there is a good reason to do otherwise (more complex [0-31], unless there is a good reason to do otherwise (more complex
encoding than single bit positions may be used in the future, to encoding than single bit positions may be used in the future, to
access the 2^32 value space). access the 2^32 value space).
6.3. Experimental Numbers 6.3. Experimental Numbers
No experimental values are currently assigned for the Modes Registry. No experimental values are currently assigned for the Modes Registry.
6.4. Initial Registry Contents 6.4. Initial Registry Contents
TWAMP Modes Registry TWAMP Modes Registry
Value Description Semantics Definition Value Description Semantics Definition
0 Reserved 0 Reserved RFC 5618
1 Unauthenticated RFC4656, Section 3.1 1 Unauthenticated RFC4656, Section 3.1
2 Authenticated RFC4656, Section 3.1 2 Authenticated RFC4656, Section 3.1
4 Encrypted RFC4656, Section 3.1 4 Encrypted RFC4656, Section 3.1
8 Unauth. TEST protocol, this document, Section 3.1 8 Unauth. TEST protocol, RFC 5618, Section 3.1
Encrypted CONTROL Encrypted CONTROL
7. Acknowledgements 7. Acknowledgements
The authors would like to thank Len Ciavattone for helpful review and The authors would like to thank Len Ciavattone and Joel Jaeggli for
comments. helpful review and comments.
8. Normative References 8. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M. [RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M.
Zekauskas, "A One-way Active Measurement Protocol Zekauskas, "A One-way Active Measurement Protocol
(OWAMP)", RFC 4656, September 2006. (OWAMP)", RFC 4656, September 2006.
skipping to change at page 10, line 10 skipping to change at page 8, line 10
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. [RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J.
Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)",
RFC 5357, October 2008. RFC 5357, October 2008.
Authors' Addresses Authors' Addresses
Al Morton Al Morton
AT&T Labs AT&T Labs
200 Laurel Avenue South 200 Laurel Avenue South
Middletown,, NJ 07748 Middletown, NJ 07748
USA USA
Phone: +1 732 420 1571 Phone: +1 732 420 1571
Fax: +1 732 368 1192 Fax: +1 732 368 1192
Email: acmorton@att.com EMail: acmorton@att.com
URI: http://home.comcast.net/~acmacm/ URI: http://home.comcast.net/~acmacm/
Kaynam Hedayat Kaynam Hedayat
EXFO EXFO
285 Mill Road 285 Mill Road
Chelmsford, MA 01824 Chelmsford, MA 01824
USA USA
Phone: +1 Phone: +1 978 367 5611
Fax: +1 Fax: +1 978 367 5700
Email: kaynam.hedayat@exfo.com EMail: kaynam.hedayat@exfo.com
URI: http://www.exfo.com/ URI: http://www.exfo.com/
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