draft-ietf-ccamp-wson-signaling-05.txt   draft-ietf-ccamp-wson-signaling-06.txt 
Network Working Group G. Bernstein Network Working Group G. Bernstein
Internet Draft Grotto Networking Internet Draft Grotto Networking
Intended status: Standards Track Sugang Xu Intended status: Standards Track Sugang Xu
NICT NICT
Expires: August 2013 Y.Lee Expires: January 2014 Y.Lee
Huawei Huawei
G. Martinelli G. Martinelli
Cisco Cisco
Hiroaki Harai Hiroaki Harai
NICT NICT
February 18, 2013 July 5, 2013
Signaling Extensions for Wavelength Switched Optical Networks Signaling Extensions for Wavelength Switched Optical Networks
draft-ietf-ccamp-wson-signaling-05.txt draft-ietf-ccamp-wson-signaling-06.txt
Abstract Abstract
This memo provides extensions to Generalized Multi-Protocol Label This memo provides extensions to Generalized Multi-Protocol Label
Switching (GMPLS) signaling for control of wavelength switched Switching (GMPLS) signaling for control of wavelength switched
optical networks (WSON). Such extensions are necessary in WSONs optical networks (WSON). Such extensions are necessary in WSONs
under a number of conditions including: (a) when optional under a number of conditions including: (a) when optional
processing, such as regeneration, must be configured to occur at processing, such as regeneration, must be configured to occur at
specific nodes along a path, (b) where equipment must be configured specific nodes along a path, (b) where equipment must be configured
to accept an optical signal with specific attributes, or (c) where to accept an optical signal with specific attributes, or (c) where
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Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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1. Introduction...................................................3 1. Introduction...................................................3
2. Terminology....................................................3 2. Terminology....................................................3
3. Requirements for WSON Signaling................................4 3. Requirements for WSON Signaling................................4
3.1. WSON Signal Characterization..............................4 3.1. WSON Signal Characterization..............................4
3.2. Per LSP Network Element Processing Configuration..........5 3.2. Per LSP Network Element Processing Configuration..........5
3.3. Bi-Directional WSON LSPs..................................5 3.3. Bi-Directional WSON LSPs..................................5
3.4. Distributed Wavelength Assignment Selection Method........6 3.4. Distributed Wavelength Assignment Selection Method........6
3.5. Out of Scope..............................................6 3.5. Out of Scope..............................................6
4. WSON Signal Traffic Parameters, Attributes and Processing......6 4. WSON Signal Traffic Parameters, Attributes and Processing......6
4.1. Traffic Parameters for Optical Tributary Signals..........7 4.1. Traffic Parameters for Optical Tributary Signals..........7
4.2. Signal Attributes and Processing Capabilities.............7 4.2. WSON Processing Object Encoding...........................7
4.3. Wavelength Assignment Method Selection....................8 4.3. Signal Attributes and Processing Capabilities.............8
4.4. WSON Processing Object Encoding...........................9 4.4. Wavelength Assignment Method Selection....................8
5. Bidirectional Lightpath Setup.................................10 5. Bidirectional Lightpath Setup.................................10
6. Security Considerations.......................................10 6. Security Considerations.......................................10
7. IANA Considerations...........................................11 7. IANA Considerations...........................................11
8. Acknowledgments...............................................11 8. Acknowledgments...............................................11
9. References....................................................12 9. References....................................................12
9.1. Normative References.....................................12 9.1. Normative References.....................................12
9.2. Informative References...................................13 9.2. Informative References...................................13
Author's Addresses...............................................15 Author's Addresses...............................................15
Intellectual Property Statement..................................16 Intellectual Property Statement..................................16
Disclaimer of Validity...........................................17 Disclaimer of Validity...........................................17
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DWDM: Dense Wavelength Division Multiplexing. DWDM: Dense Wavelength Division Multiplexing.
FOADM: Fixed Optical Add/Drop Multiplexer. FOADM: Fixed Optical Add/Drop Multiplexer.
ROADM: Reconfigurable Optical Add/Drop Multiplexer. A reduced port ROADM: Reconfigurable Optical Add/Drop Multiplexer. A reduced port
count wavelength selective switching element featuring ingress and count wavelength selective switching element featuring ingress and
egress line side ports as well as add/drop side ports. egress line side ports as well as add/drop side ports.
RWA: Routing and Wavelength Assignment. RWA: Routing and Wavelength Assignment.
Wavelength Conversion/Converters: The process of converting an Wavelength Conversion/Converters: The process of converting
information bearing optical signal centered at a given wavelength to information bearing optical signal centered at a given wavelength to
one with "equivalent" content centered at a different wavelength. one with "equivalent" content centered at a different wavelength.
Wavelength conversion can be implemented via an optical-electronic- Wavelength conversion can be implemented via an optical-electronic-
optical (OEO) process or via a strictly optical process. optical (OEO) process or via a strictly optical process.
WDM: Wavelength Division Multiplexing. WDM: Wavelength Division Multiplexing.
Wavelength Switched Optical Networks (WSON): WDM based optical Wavelength Switched Optical Networks (WSON): WDM based optical
networks in which switching is performed selectively based on the networks in which switching is performed selectively based on the
center wavelength of an optical signal. center wavelength of an optical signal.
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can be important to include key lightpath characteristics as traffic can be important to include key lightpath characteristics as traffic
parameters in signaling [RFC6163]. parameters in signaling [RFC6163].
4.1. Traffic Parameters for Optical Tributary Signals 4.1. Traffic Parameters for Optical Tributary Signals
In [RFC3471] we see that the G-PID (client signal type) and bit rate In [RFC3471] we see that the G-PID (client signal type) and bit rate
(byte rate) of the signals are defined as parameters and in (byte rate) of the signals are defined as parameters and in
[RFC3473] they are conveyed Generalized Label Request object and the [RFC3473] they are conveyed Generalized Label Request object and the
RSVP SENDER_TSPEC/FLOWSPEC objects respectively. RSVP SENDER_TSPEC/FLOWSPEC objects respectively.
4.2. Signal Attributes and Processing Capabilities 4.2. WSON Processing Object Encoding
Section 3.2. provided the requirements for signaling to indicate to
a particular NE along an LSP what type of processing to perform on
an optical signal or how to configure that NE to accept or transmit
an optical signal with particular attributes.
To target a specific node, this section defines a WSON_Processing
object as part of the LSP_REQUIRED_ATTRIBUTE and follows procedures
defined in [RSVP-RO].
The content of this object is defined in the subsequent sections.
(See Section 4.3 for <RBInformation> TLV and Section 4.4 for
<WavelengthSelection> TLV, respectively.)
<WSON_Processing> ::= <RBInformation> [<RBInformation>]
[<WavelengthSelection>]
The WSON Processing object encoding is defined as:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Value ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: to be defined by IANA
Value: sub-TLVS according to section 4.3 and 4.4
4.3. Signal Attributes and Processing Capabilities
The [WSON-Encode] already provides all necessary definitions and The [WSON-Encode] already provides all necessary definitions and
encoding for WSON information required for signaling. In particular, encoding for WSON information required for signaling. In particular,
the Resource block information sub-TLV contains, among others, a the Resource block information sub-TLV contains, among others, a
list of available Optical Interface Classes and processing list of available Optical Interface Classes and processing
capabilities. capabilities.
<RBInformation> is defined in Section 5.1 of [WSON-Encode]. <RBInformation> is defined in Section 4.1 of [WSON-Encode].
Type Sub-TLV Type Sub-TLV
1 (TBA) <RBInformation> 1 (TBA) <RBInformation>
One <RBInformation> sub-TLV MUST always be present in the At least one <RBInformation> sub-TLV MUST always be present in the
WSON_SIGNALING object;otherwise, a PathErr shall be generated. At WSON_Processing Object otherwise a PathErr SHALL be generated. At
most two <RBInformation> sub-TLVs MAY be present in the most two <RBInformation> sub-TLVs MAY be present in the
WSON_SIGNALING object. If more than two objects are encountered, two WSON_Processing Object. If more than two objects are encountered,
MUST be processed and the rest SHOULD be ignored. two MUST be processed and the rest SHOULD be ignored.
The <RBInformation> contains several information. The following The <RBInformation> contains several information as defined by
processing rules apply: [WSON-Encode]. The following processing rules apply:
RB Set Field MAY contain more than one RB Indetifier. Only the first RB Set Field MAY contain more than one RB Indetifier. Only the first
one MUST be processed, the others SHOULD be ignored. one MUST be processed, the others SHOULD be ignored.
The Optical Interface Class List, Input Bit Range List and The I an E flags MUST be set according to bidirectional LSP
Processing Capability List MAY contain more than one element. Only signaling and the numbers of RBInformation subobjects available. In
the first MUST be processed, the others SHOULD be ignored. case of unidirectional signaling, only one RBInformartion sub-object
MUST be processed and I/E bits can be safely ignored. In case of
bidirectional signaling: if only one RBInformartion is available,
bits I and E MUST be both set to 1, if two RBInformation sub-objects
are available, bits I and E MUST have different values.
4.3. Wavelength Assignment Method Selection The rest of information available within RBInformation sub-object is
Optical Interface Class List, Input Bit Range List and Processing
Capability List. Lists MAY contain one or more elements.
4.4. Wavelength Assignment Method Selection
Routing + Distributed wavelength assignment (R+DWA) is one of the Routing + Distributed wavelength assignment (R+DWA) is one of the
options defined by the [RFC6163]. The output from the routing options defined by the [RFC6163]. The output from the routing
function will be a path but the wavelength will be selected on a function will be a path but the wavelength will be selected on a
hop-by-hop basis. hop-by-hop basis.
Under this hypothesis the node initiating the signaling process Under this hypothesis the node initiating the signaling process
needs to declare its own wavelength availability (through a needs to declare its own wavelength availability (through a
label_set object). Each intermediate node may delete some labels due label_set object). Each intermediate node may delete some labels due
to connectivity constraints or its own assignment policy. At the to connectivity constraints or its own assignment policy. At the
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2 <WavelengthSelection> 2 <WavelengthSelection>
0 1 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|W| WA Method | Reserved | |W| WA Method | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where: Where:
W is a bit, 0 same wavelength in both directions, 1 may use . W is a bit, 0 same wavelength in both directions, 1 may use
different wavelengths different wavelengths
Wavelength Assignment Method: 0 unspecified (any), 1 First-Fit, . Wavelength Assignment (WA) Method: 0 unspecified (any), 1
2 Random, 3 Least-Loaded (multi-fiber). Others TBD. First-Fit, 2 Random, 3 Least-Loaded (multi-fiber). Others TBD.
This sub-TLV MAY be present in the WSON_SIGNALING object. If more This sub-TLV MAY be present in the WSON_Processing Object. If more
than one sub-TLV is encountered the first one MUST be processed, the than one sub-TLV is encountered the first one MUST be processed, the
rest SHOULD be ignored. rest SHOULD be ignored.
4.4. WSON Processing Object Encoding
Section 3.2. provided the requirements for signaling to indicate to
a particular NE along an LSP what type of processing to perform on
an optical signal or how to configure that NE to accept or transmit
an optical signal with particular attributes.
To target a specific node, this section defines a WSON_SIGNALING
object as part of the LSP_REQUIRED_ATTRIBUTE and follows procedures
defined in [RSVP-RO].
The content of this object is defined in the previous sections 4.2
and 4.3:
<WSON_SIGNALING> ::= <RBInformation> [<RBInformation>]
[<WavelengthSelection>]
The WSON_SIGNALING object encoding is defined as:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Value ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: to be defined by IANA
Value: sub-TLVS according to section 4.2 and 4.3
5. Bidirectional Lightpath Setup 5. Bidirectional Lightpath Setup
With the wavelength continuity constraint in CI-incapable [RFC3471] With the wavelength continuity constraint in CI-incapable [RFC3471]
WSONs, where the nodes in the networks cannot support wavelength WSONs, where the nodes in the networks cannot support wavelength
conversion, the same wavelength on each link along a unidirectional conversion, the same wavelength on each link along a unidirectional
lightpath should be reserved. In addition to the wavelength lightpath should be reserved. In addition to the wavelength
continuity constraint, requirement 3.3 gives us another constraint continuity constraint, requirement 3.3 gives us another constraint
on wavelength usage in data plane, in particular, it requires the on wavelength usage in data plane, in particular, it requires the
same wavelength to be used in both directions. [RFC6163] in section same wavelength to be used in both directions. [RFC6163] in section
6.1 reports on the implication to GMPLS signaling related to both 6.1 reports on the implication to GMPLS signaling related to both
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Current GMPLS solution defines a bidirectional LSP (as defined by Current GMPLS solution defines a bidirectional LSP (as defined by
[RFC3471]). The label distribution is based on Label_Set and [RFC3471]). The label distribution is based on Label_Set and
Upstream_Label objects. In case of specific constraints such as the Upstream_Label objects. In case of specific constraints such as the
same wavelengths in both directions, it may require several same wavelengths in both directions, it may require several
signaling attempts using information from the Acceptable_Label_Set signaling attempts using information from the Acceptable_Label_Set
received from path error messages. Since this mechanism is currently received from path error messages. Since this mechanism is currently
available and proven to work, no additional extensions are needed available and proven to work, no additional extensions are needed
for WSON. Potential optimizations are left for further studies. for WSON. Potential optimizations are left for further studies.
The usage of <WSON Processing> object for the bidirectional case is The usage of WSON Processing object for the bidirectional case is
the same as per unidirectional. When an intermediate node uses the same as per unidirectional. When an intermediate node uses
information from this object to instruct a node about wavelength information from this object to instruct a node about wavelength
regeneration, the same information applies to both downstream and regeneration, the same information applies to both downstream and
upstream directions. upstream directions.
Some implementations may prefer using two unidirectional LSPs. This Some implementations may prefer using two unidirectional LSPs. This
solution has been always available as per [RFC3209] however recent solution has been always available as per [RFC3209] however recent
work introduces the association concept [RFC4872] and [ASSOC-Info]. work introduces the association concept [RFC4872] and [ASSOC-Info].
Recent transport evolutions [ASSOC-ext] provide a way to associate Recent transport evolutions [ASSOC-ext] provide a way to associate
two unidirectional LSPs as a bidirectional LSP. In line with this, a two unidirectional LSPs as a bidirectional LSP. In line with this, a
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Furthermore the additional information distributed in order to Furthermore the additional information distributed in order to
address the RWA problem represents a disclosure of network address the RWA problem represents a disclosure of network
capabilities that an operator may wish to keep private. capabilities that an operator may wish to keep private.
Consideration should be given to securing this information. Consideration should be given to securing this information.
7. IANA Considerations 7. IANA Considerations
A new LSP_REQUIRED_ATTRIBUTE type is required A new LSP_REQUIRED_ATTRIBUTE type is required
TBA: WSON Object (Section 4.4) TBA: WSON Processing Object (Section 4.2)
Two types of sub-TLV are allowed within the WSON object Two types of sub-TLV are allowed within the WSON Processing Object
Value Sub-TLV Value Sub-TLV
1 (Proposed) WSON Processing Capabilities (Section 4.2) 1 (Proposed) WSON Processing Capabilities (Section 4.3)
2 (Proposed) WSON Wavelength Assignments (Section 4.3) 2 (Proposed) WSON Wavelength Assignments (Section 4.4)
8. Acknowledgments 8. Acknowledgments
Authors would like to thanks Lou Berger and Cyril Margaria for Authors would like to thanks Lou Berger and Cyril Margaria for
comments and suggestions. comments and suggestions.
9. References 9. References
9.1. Normative References 9.1. Normative References
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(RSVP-TE)", RFC 3477, January 2003. (RSVP-TE)", RFC 3477, January 2003.
[RFC5420] Farrel, A., Ed., Papadimitriou, D., Vasseur, J.-P., and A. [RFC5420] Farrel, A., Ed., Papadimitriou, D., Vasseur, J.-P., and A.
Ayyangar, " Encoding of Attributes for MPLS LSP Ayyangar, " Encoding of Attributes for MPLS LSP
Establishment Using Resource Reservation Protocol Traffic Establishment Using Resource Reservation Protocol Traffic
Engineering (RSVP-TE)", RFC 5420, February 2006. Engineering (RSVP-TE)", RFC 5420, February 2006.
[WSON-Encode] Bernstein G., Lee Y., Li D., and W. Imajuku, "Routing [WSON-Encode] Bernstein G., Lee Y., Li D., and W. Imajuku, "Routing
and Wavelength Assignment Information Encoding for and Wavelength Assignment Information Encoding for
Wavelength Switched Optical Networks", draft-ietf-ccamp- Wavelength Switched Optical Networks", draft-ietf-ccamp-
rwa-wson-encode-18 (work in progress), September 2012. rwa-wson-encode-20 (work in progress).
[RSVP-RO] Margaria, C., et al, "LSP Attribute in ERO", draft-ietf- [RSVP-RO] Margaria, C., et al, "LSP Attribute in ERO", draft-ietf-
ccamp-lsp-attribute-ro (work in progress), Febrauary 2013. ccamp-lsp-attribute-ro (work in progress).
9.2. Informative References 9.2. Informative References
[WSON-CompOSPF] Y. Lee, G. Bernstein, "OSPF Enhancement for Signal [WSON-CompOSPF] Y. Lee, G. Bernstein, "OSPF Enhancement for Signal
and Network Element Compatibility for Wavelength Switched and Network Element Compatibility for Wavelength Switched
Optical Networks", work in progress: draft-lee-ccamp-wson- Optical Networks", work in progress: draft-lee-ccamp-wson-
signal-compatibility-OSPF. signal-compatibility-OSPF.
[RFC6163] Y. Lee, G. Bernstein, W. Imajuku, "Framework for GMPLS [RFC6163] Y. Lee, G. Bernstein, W. Imajuku, "Framework for GMPLS
and PCE Control of Wavelength Switched Optical Networks", and PCE Control of Wavelength Switched Optical Networks",
work in progress: draft-bernstein-ccamp-wavelength- work in progress: draft-bernstein-ccamp-wavelength-
switched-03.txt, February 2008. switched-03.txt, February 2008.
[WSON-Info] G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and [WSON-Info] G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and
Wavelength Assignment Information Model for Wavelength Wavelength Assignment Information Model for Wavelength
Switched Optical Networks", work in progress: draft-ietf- Switched Optical Networks", work in progress: draft-ietf-
ccamp-rwa-info-16, September 2012. ccamp-rwa-info-18.
[HZang00] H. Zang, J. Jue and B. Mukherjeee, "A review of routing [HZang00] H. Zang, J. Jue and B. Mukherjeee, "A review of routing
and wavelength assignment approaches for wavelength-routed and wavelength assignment approaches for wavelength-routed
optical WDM networks", Optical Networks Magazine, January optical WDM networks", Optical Networks Magazine, January
2000. 2000.
[Xu] S. Xu, H. Harai, and D. King, "Extensions to GMPLS RSVP-TE [Xu] S. Xu, H. Harai, and D. King, "Extensions to GMPLS RSVP-TE
for Bidirectional Lightpath the Same Wavelength", work in for Bidirectional Lightpath the Same Wavelength", work in
progress: draft-xu-rsvpte-bidir-wave-01, November 2007. progress: draft-xu-rsvpte-bidir-wave-01, November 2007.
skipping to change at page 16, line 4 skipping to change at page 16, line 4
P.R.China P.R.China
Email: jyf@bupt.edu.cn Email: jyf@bupt.edu.cn
Daniel King Daniel King
Old Dog Consulting Old Dog Consulting
Email: daniel@olddog.co.uk Email: daniel@olddog.co.uk
Young Lee (editor) Young Lee (editor)
Huawei Technologies Huawei Technologies
1700 Alma Drive, Suite 100 5360 Legacy Dr. Building 3
Plano, TX 75075 Plano, TX 75024
USA USA
Phone: (972) 509-5599 (x2240) Phone: (469) 277-5838
Email: ylee@huawei.com Email: leeyoung@huawei.com
Sugang Xu Sugang Xu
National Institute of Information and Communications Technology National Institute of Information and Communications Technology
4-2-1 Nukui-Kitamachi, Koganei, 4-2-1 Nukui-Kitamachi, Koganei,
Tokyo, 184-8795 Japan Tokyo, 184-8795 Japan
Phone: +81 42-327-6927 Phone: +81 42-327-6927
Email: xsg@nict.go.jp Email: xsg@nict.go.jp
Giovanni Martinelli Giovanni Martinelli
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