Internet Engineering Task Force G. Martinelli, Ed.
Internet-Draft Cisco Systems
Intended status: Standards Track A. Zanardi, Ed.
Expires: August 25, 2008 CREATE-NET
February 22, 2008
GMPLS Signaling Extensions for Optical Impairment Aware Lightpath Setup
draft-martinelli-ccamp-optical-imp-signaling-01.txt
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Copyright Notice
Copyright (C) The IETF Trust (2008).
Abstract
The problem of provisioning a lightpath in a transparent dense
wavelength division multiplexing (DWDM) optical island requires the
evaluation of of the optical impairments along the selected route.
In this draft we propose a GMPLS signaling protocol (RSVP/RSVP-TE)
extension to collect and provide the egress node the optical
impairment parameters needed to validate a lightpath setup request
feasibility.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
3. Optical Path Validation Procedure . . . . . . . . . . . . . . 4
4. Physical Parameter Classification and top level TLV . . . . . 5
5. Optical Service Parameters sub-TLV . . . . . . . . . . . . . . 7
5.1. Forward Error Correction (FEC) . . . . . . . . . . . . . . 8
5.2. Modulation Format . . . . . . . . . . . . . . . . . . . . 9
6. Optical Path Parameters sub-TLV(s) . . . . . . . . . . . . . . 9
6.1. Optical Parameter sub-TLV overview . . . . . . . . . . . . 10
6.2. Mandatory Linear Optical Parameters sub-TLVs . . . . . . . 10
6.2.1. Optical Power . . . . . . . . . . . . . . . . . . . . 11
6.2.2. Optical Signal to Noise Ratio . . . . . . . . . . . . 11
6.3. Optional Linear Optical Parameters sub-TLVs . . . . . . . 11
6.3.1. Chromatic Dispersion (CD) . . . . . . . . . . . . . . 11
6.3.2. Polarization Mode Dispersion (PMD) . . . . . . . . . . 11
6.3.3. Cross-Talk (XT) . . . . . . . . . . . . . . . . . . . 11
7. Message Fragmentation . . . . . . . . . . . . . . . . . . . . 11
8. Backward Compatibility . . . . . . . . . . . . . . . . . . . . 14
9. Error management . . . . . . . . . . . . . . . . . . . . . . . 14
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 14
11. Contributing Authors . . . . . . . . . . . . . . . . . . . . . 14
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
13. Security Considerations . . . . . . . . . . . . . . . . . . . 16
14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
14.1. Normative References . . . . . . . . . . . . . . . . . . . 16
14.2. Informative References . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17
Intellectual Property and Copyright Statements . . . . . . . . . . 19
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1. Introduction
The current Generalized Multi-Protocol Label Switching (GMPLS)
specification [RFC3945] and the signaling related documents
([RFC3471], [RFC3473], [RFC4328]) support optical interfaces with
different switching capability to setup a lightpath while [RFC4054]
defines the impairments to be considered in optical routing.
[I-D.bernstein-ccamp-wavelength-switched], defines a framework
identifying the key components and issues pertaining to wavelength
switched optical networks (WSON).
[I-D.otani-ccamp-gmpls-lambda-labels] proposes a global semantic for
wavelength generalized labels taking into account lightpath specific
needs.
In transparent optical networks, physical impairments incurred by
non-ideal optical transmission medium accumulate along an optical
path. Because of these impairments even if there is physical
connectivity (fibers, wavelengths, and nodes) between the ingress and
egress nodes, there is no guarantee that the optical signal (light)
reaches the Egress node with acceptable signal quality, for example
in terms of BER/OSNR/Q-factor limit. For a successful lightpath
provisioning in a WSON, the set up process must be aware of a set of
physical impairments that has effect on the lightpath. A complete
set of physical impairments will include linear and non-linear
impairments. This preliminary draft proposes a way to collect the
optical path linear impairments in the signaling phase by providing
suitable extensions to signaling protocol (RSVP/RSVP-TE) assuming
that non-linear impairments effects are handled in the network design
phase considering a bounded OSNR margin [RFC4054].
The management of physical impairments is done only in the signaling
process and it does not require any extension to the traffic
engineering database and IGP routing protocols.
The set of parameters carried by the signaling protocol is divided
into optical service parameters and optical path parameters:
o The optical service parameters describe the requested signal type,
are related to the characteristics of the transponder at ingress
node and hence are not changed at transit nodes.
o The optical path parameters describe the signal characteristics
evolution along the path from ingress node to egress node, are
related to the characteristics of the various links/subsystems and
are updated at each transit node. They are divided into mandatory
and optional parameters. The mandatory parameters are related to
feasibility constraints such as power and OSNR, whereas the
optional parameters are expandable linear impairments such as
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chromatic dispersion (CD), polarization mode dispersion (PMD),
crosstalk, etc. The optional parameters can be used to evaluate
the feasibility of a lightpath more accurately as an alternate
solution to the bounded OSNR margin evaluation. Parameter update
methods might use appropriate physical models and are out of scope
of this document.
2. Conventions Used in This Document
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].
In additions this document will use terminology from [RFC2205],
[RFC3209], [RFC4054], and [I-D.bernstein-ccamp-wavelength-switched].
3. Optical Path Validation Procedure
The signaling based validation of an optical path in downstream
direction in a transparent network (lambda switched LSP) is
implemented by the following procedure:
o The ingress node signals in the Path message the supported signal
types (FEC and modulation format) and wavelength set (encoded in
the LABEL_SET Object) depending on available local transponders.
o Transit nodes update the Path message pruning non cross-
connectable wavelengths (LABEL_SET Object) and computing or
measuring the path optical characteristics up to the outgoing
interface (optical impairments).
o The egress node selects the wavelength and the signal type based
on the signaled optical impairments and the available local
transponders (supported wavelengths, sensitivity to optical
impairments) and signals the selection in the Resv message.
o Transit nodes process the Resv message cross-connecting the
selected wavelength in incoming and outgoing interfaces
(wavelength continuity constraint).
o The ingress node cross-connects the selected wavelength to a local
transponder supporting the selected signal type (FEC and
modulation format).
This procedure forces the meeting of the wavelength continuity
constraint: the final effect of pruning wavelengths (e.g. removing
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labels from the LABEL_SET object) in transit nodes is the
implementation of a wavelength selection process in the signaling
phase. The wavelength assignment will be done at the egress node
among all available wavelength for the LSP. The criteria used by the
egress node to assign the wavelength is out of the scope of this
document.
In the Path message processing, the unavailability of cross-
connectable wavelength in transit nodes or of transponders supporting
the signal in the egress node causes the request failure (PathErr
message).
In the Resv message processing, the unavailability of the selected
wavelength in transit nodes or of transponders supporting the signal
in the ingress node (race condition in allocating resources) causes
the request failure (ResvErr message).
In this document, only the encoding in the RSVP messages of the
optical information needed to support the described procedure is
defined. The specific policies used to select the resources
(wavelength and transponders), the models to compute the optical
impairments and the procedure to validate the signal with respect to
the transponder sensitivity are not in the scope of this document.
4. Physical Parameter Classification and top level TLV
RSVP/RSVP-TE requires the following additional information in order
to be aware of optical impairments and setup optically feasible
lightpaths:
o Optical Service Parameters.
The standard GENERALIZED_LABEL_REQUEST and TSPEC/FLOW_SPEC objects
support the encoding of the information related to service type
and service QoS. However for DWDM networks the egress node of an
LSP has to know a certain set of specific optical parameters
related to the transmitting interface. Section 5 reports details
of these parameters and their encoding.
o Optical Path Parameters.
These attributes are required to support transmission of physical
impairment parameters for the optical path feasibility evaluation.
Details are presented in Section 6.
This document defines how to encode the above information through new
TLVs according to [RFC4420].
The proposed encoding scheme for the optical parameters defines a TLV
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(channel optical physical information) associated to a wavelength
containing a sub-TLV for each service and path parameter.
Additional set of parameters can be added without affecting the
already defined encoding.
A TLV sub-object for each available wavelength (Path message) or
selected wavelength (Resv message) is encoded in an
LSP_REQUIRED_ATTRIBUTES Object.
The TLV sub-object encoding is defined in the next picture.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Wavelength ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Parameters Sub-TLV Sequence //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1
o Type: optical channel physical parameters info TLV type (TBA).
o Length: length of the TLV object in bytes without the 4 byte
header.
o Wavelength ID: wavelength label identifier according to
[I-D.otani-ccamp-gmpls-lambda-labels].
o Parameters Sub-TLV Sequence: service and path parameters values.
The TLVs wavelength ID value must be consistent with the presence of
LABEL_SET objects and its actions as defined within [RFC3471] and
[RFC3473].
The Sub-TLV format is defined in the next picture
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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 | Flags | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Value //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2
Type: Sub-TLV type
Flags: bit-mask defining the management of the Sub-TLV
bit 0: if set the parameter is mandatory, otherwise it is
optional.
bit 1: if set the parameter is variable and MUST be updated
with the local value, otherwise it is a constant value set by
the ingress node.
bit 2-7: not used.
Length: Value field length in bytes
Value: variable length Sub-TLV content
The Flags field defines how transit nodes manage the Sub-TLV:
o Constant sub-TLVs are forwarded as-is.
o Mandatory non constant sub-TLVs MUST be updated with the local
parameter value, if the parameter is not managed by the node, it
MUST reject the request with a failure.
o Optional non constant sub-TLVs MUST be updated with the local
parameter value, if the parameter is not managed by the node, it
MUST silently drop it from the TLV (the value would be
inaccurate).
5. Optical Service Parameters sub-TLV
The Optical Service Parameters define the signal transmissions
characteristics at the ingress node. This type of information is
required at the egress node to verify the optical signal
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compatibility.
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 | Flags | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FEC 1 | Mod Format 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FEC n | Mod Format n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3
Type: sub-TLV type (=1)
Flags: Mandatory, Constant
Length: length of the sub-TLV value in bytes
FEC: supported Forward Error Correction Modes (see Section 5.1
Mod Format: supported modulation formats (see Section 5.2)
associated with the FEC.
This sub-TLV is used in the PATH message to signal the full list of
optical parameters associated with the interface (signal types and
wavelengths) available at the ingress node. A DWDM interface might
have several sets of optical parameters available, for example a
tunable interface has a set of possible wavelengths, together with a
set of possible FEC encoding or modulation formats. In the RESV
message this information is associated to the selected receiving
interface at the egress node. In the RESV message only one tuple
(FEC, Mod Format) will be specified.
5.1. Forward Error Correction (FEC)
FEC (16 bits) field is the Forward Error Correction and has the
following values:
0: no FEC
1: standard FEC (according to [ITU.G709])
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2-9: super-FEC according to sub clauses from I.2 to I.9 of
[ITU.G975.1]
Values with the format 1bbbbbbbbbbbbbbb are left to represent vendor
specific or proprietary FEC encoding.
5.2. Modulation Format
Mod Format (16 bits) is the modulation and has the following values:
0: NRZ
1: Duo Binary
2: DPSK
Other values might be defined in the future as technology advance.
Values with the format 1bbbbbbbbbbbbbbb are left to represent vendor
specific or proprietary modulation formats.
6. Optical Path Parameters sub-TLV(s)
This set of parameters is carried in the PATH message for each
available wavelength to allow the optical feasibility evaluation. At
each hop, the optical node MUST update these values according to
information locally available at the node (say internal amplifiers,
wavelength cross connect, etc.).
The way an optical node gets knowledge of this required information
(e.g. through NMS, auto-discovery etc.) is out of the scope of this
document and highly depends on specific equipment implementation.
This document defines two groups of linear optical parameters.
Mandatory Linear Optical Parameters
This set includes Optical Signal Power and the OSNR with
associated variances. It represents the minimum set to asses the
feasibility of an optical path. This set will be encoded using
mandatory sub-TLVs.
Optional Linear Optical Parameters
This set includes CD, PMD, XT with associated variances. These
parameters represent an additional set to allow a more accurate
optical feasibility evaluation. This set will be encoded using
optional sub-TLVs.
Separation between mandatory and optional parameters allows a rough
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optical feasibility evaluation where network elements support at
least the mandatory set. Depending on how a WSON is designed, the
usage of the mandatory set could be an operational choice not to
overwhelm the control plane while maintaining reliable feasibility
estimation. Moreover it might happens that not all nodes in a
networks support the full set of optical path parameters. With this
classification, the lightpath signaling still continues to work
although with a less accurate evaluation.
The choice of the optional set of parameters depends on several
considerations. They are among those reported by the [RFC4054] and
provide sufficient accuracy for the linear impairments evaluation.
6.1. Optical Parameter sub-TLV overview
Each optical parameter will be encoded using the following format:
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 | Flags | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Parameter Value |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optical Parameter Variance |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4
Type: sub_TLV type > 1.
Flags: mandatory or optional according to each parameter
classification, variable.
Length: 4 octets or 8 octets depending if the optical parameter
has the variance value associated.
Value associated with the optical parameter.
Variance: the error estimation for optical parameter value
calculation. Depending on the length value may not be present.
6.2. Mandatory Linear Optical Parameters sub-TLVs
The Sub-TLVs encode the following optical parameters of a channel
(wavelength) measured at the node egress interface. Flags are:
mandatory, variable.
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6.2.1. Optical Power
Type = 2.
Value: 32bit IEEE floating point number. Measurement Unit: dBm.
6.2.2. Optical Signal to Noise Ratio
Type = 3.
Value: 32bit IEEE floating point number. Measurement Unit: dB.
6.3. Optional Linear Optical Parameters sub-TLVs
The Sub-TLVs encode the following optical parameters of a channel
(wavelength) measured at the node egress interface. Flags are:
optional, variable.
6.3.1. Chromatic Dispersion (CD)
Type = 4.
Value: 32bit IEEE floating point number. Measurement Unit: ps/nm.
6.3.2. Polarization Mode Dispersion (PMD)
Type = 5.
Value: 32bit IEEE floating point number. Measurement Unit: ps.
6.3.3. Cross-Talk (XT)
Type = 6.
Value: 32bit IEEE floating point number. Measurement Unit: dB.
7. Message Fragmentation
In certain cases, the state information carried by the Path message
can be quite large. Size estimation for a physical Optical Channel
TLV (see Figure 1) can be the following: 8 bytes for type, length and
wavelength ID plus, 16 bytes for the Optical Service Parameters sub-
TLV considering 3 FEC/modulation format combinations plus, 24 bytes
for the Mandatory Linear Optical Path parameters plus 36 bytes for
the Optional Linear Optical Parameter sub-TLV. Total is 48 bytes for
each wavelength by just considering mandatory sub-TLVs and 84 bytes
by considering also the optional part. Given the number of
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wavelengths today available in DWDM networks, the size of the path
message end up in large values. For example to signal just 32
wavelengths the size required for the physical optical parameters
ranges at least from 1536 to 2688 bytes.
A possible option is to let the application layer requesting the
lightpath setup to decide how many wavelengths to signal according to
the MTU available. For example, having an MTU of 1500 bytes the
application layer might signal only 10 wavelengths with the full set
of parameters taking up 840 bytes, or it might decide to signal 20
wavelengths with just the mandatory parameters. Note that, according
to procedure described within Section 3, the message size may
decrease as long as the Path message pass through transit nodes.
A second solution proposed here implements the semantic fragmentation
as suggested by RSVP [RFC2205]. The proposed encoding extends the
SENDER_TEMPLATE Object with a new Class Type (derived from the
LSP_TUNNEL_IPv4 and LSP_TUNNEL_IPv6 RSVP-TE [RFC3209]). The Object
includes the additional information on the "fragment id" and on the
requested policy for the channel selection at the egress node
Class = SENDER_TEMPLATE, FRAGREQ_LSP_TUNNEL_IPv4 C-Type = TBA
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TotalNo | MsgId | P | Timeout |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5
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Class = SENDER_TEMPLATE, FRAGREQ_LSP_TUNNEL_IPv6 C-Type = TBA
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| IPv6 tunnel sender address |
+ +
| (16 bytes) |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TotalNo | MsgId | P | Timeout |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6
Besides the fields already defined in the SENDER_TEMPLATE, the
following fields are defined:
o TotalNo: 8 bit integer representing the total number of Path
messages issued by the ingress node to setup a single lightpath.
When this values is equals to 1 all the other fields MUST be
ignored.
o MsgId: 8 bit integer representing the sequential number of a
single Path request. Its value must be between 1 and TotalNo,
both inclusive.
o P: Policy the egress node must apply upon receiving a fragmented
path request:
1: Take the first message arrived and ignore the
following ones.
2: After the first message arrives, wait for any message
within the specified Timeout.
3: After the first message arrives, waits for all
messages. Fail, if the timeout expires, and there's at
least one message missing
The egress node should "reject" (PathErr) all the requests except
for the selected one, even if it could rely on the RSVP timeout
to clear the unselected requests status in upstream nodes.
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o Timeout: 12 bits integer number representing the timeout value
used by the policy. The value is in s/100 (hundreds of seconds)
All messages MUST have the same value.
This type of encoding is a generic solution to manage the semantic
fragmentation and its not strictly related to optical parameters
encoding.
8. Backward Compatibility
The TLV usage as defined by [RFC4420] will guarantee the co-existence
of nodes supporting normal RSVP-TE operations and node with optical
impairment signaling capability.
A service with the new feature (optical feasibility evaluation) can
be setup only if all the nodes in the path support the extensions.
Optical Path Parameters are updated hop-by-hop and evaluated at
egress node. If a transit node does not support the extensions the
collected information is unreliable and the Path request MUST be
rejected.
9. Error management
No additional error code is introduced to manage requests failures;
the behavior defined in [RFC4420] applies to the management of the
LSP_REQUIRED_ATTRIBUTES Object.
10. Acknowledgments
11. Contributing Authors
This document was the collective work of several authors. The text
and content of this document was contributed by the editors and the
co-authors listed below (the contact information for the editors
appears in appropriate section and is not repeated below):
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Gabriele Maria Galimberti Alberto Tanzi
Cisco Systems Cisco Systems
via Philips 12 via Philips 12
Monza 20052 Monza 20052
Italy Italy
Email: ggalimbe@cisco.com Email: atanzi@cisco.com
Domenico La Fauci Stefano Piciaccia
Cisco Systems Cisco Systems
via Philips 12 via Philips 12
Monza 20052 Monza 20052
Italy Italy
Email: dlafauci@cisco.com Email: spiciacc@cisco.com
Elio Salvadori Yabin Ye
CREATE-NET CREATE-NET
via alla Cascata 56 C, Povo via alla Cascata 56 C, Povo
Trento 38100 Trento 38100
Italy Italy
Email: elio.salvadori@create-net.org Email: yabin.ye@create-net.org
Chava Vijaya Saradhi
CREATE-NET
via alla Cascata 56 C, Povo
Trento 38100
Italy
Email: saradhi.chava@create-net.org
12. IANA Considerations
This memo needs the following request to IANA
TLV (see Figure 1 in Section 4)
New class type for sender template (see Section 7)
All drafts are required to have an IANA considerations section (see
the update of RFC 2434 [I-D.narten-iana-considerations-rfc2434bis]
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for a guide). If the draft does not require IANA to do anything, the
section contains an explicit statement that this is the case (as
above). If there are no requirements for IANA, the section will be
removed during conversion into an RFC by the RFC Editor.
13. Security Considerations
This document introduces no new security considerations to [RFC3473].
GMPLS security is described in section 11 of [RFC3471] and refers to
[RFC3209] for RSVP-TE.
14. References
14.1. Normative References
[ITU.G709]
International Telecommunications Union, "Interface for the
Optical Transport Network (OTN)", ITU-T Recommendation
G.709, March 2003.
[ITU.G975.1]
International Telecommunications Union, "Forward Error
Correction for high bit rate DWDM Submarine Systems", ITU-
T Recommendation G.975, February 2004.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, September 1997.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.
[RFC4328] Papadimitriou, D., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Extensions for G.709 Optical
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Transport Networks Control", RFC 4328, January 2006.
[RFC4420] Farrel, A., Papadimitriou, D., Vasseur, J., and A.
Ayyangar, "Encoding of Attributes for Multiprotocol Label
Switching (MPLS) Label Switched Path (LSP) Establishment
Using Resource ReserVation Protocol-Traffic Engineering
(RSVP-TE)", RFC 4420, February 2006.
14.2. Informative References
[I-D.bernstein-ccamp-wavelength-switched]
Bernstein, G., "Framework for GMPLS and PCE Control of
Wavelength Switched Optical Networks",
draft-bernstein-ccamp-wavelength-switched-03 (work in
progress), February 2008.
[I-D.narten-iana-considerations-rfc2434bis]
Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs",
draft-narten-iana-considerations-rfc2434bis-08 (work in
progress), October 2007.
[I-D.otani-ccamp-gmpls-lambda-labels]
Otani, T., Guo, H., Miyazaki, K., Caviglia, D., and Z.
Ali, "Document:
draft-otani-ccamp-gmpls-lambda-labels-01.txt",
draft-otani-ccamp-gmpls-lambda-labels-01 (work in
progress), November 2007.
[RFC3945] Mannie, E., "Generalized Multi-Protocol Label Switching
(GMPLS) Architecture", RFC 3945, October 2004.
[RFC4054] Strand, J. and A. Chiu, "Impairments and Other Constraints
on Optical Layer Routing", RFC 4054, May 2005.
Authors' Addresses
Giovanni Martinelli (editor)
Cisco Systems
via Philips 12
Monza 20052
Italy
Email: giomarti@cisco.com
Martinelli & Zanardi Expires August 25, 2008 [Page 17]
Internet-Draft Optical Impairment Signaling February 2008
Andrea Zanardi (editor)
CREATE-NET
via alla Cascata 56 C, Povo
Trento 38100
Italy
Email: andrea.zanardi@create-net.org
Martinelli & Zanardi Expires August 25, 2008 [Page 18]
Internet-Draft Optical Impairment Signaling February 2008
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