Network Working Group Y. Lee, Ed.
Internet Draft Huawei Technologies
Intended status: Standard R. Casellas, Ed.
Expires: September 2013 CTTC
March 26, 2013
PCEP Extension for WSON Routing and Wavelength Assignment
draft-ietf-pce-wson-rwa-ext-00.txt
Abstract
This draft provides the Path Computation Element communication
Protocol (PCEP) extensions for the support of Routing and Wavelength
Assignment (RWA) in Wavelength Switched Optical Networks (WSON).
Lightpath provisioning in WSONs requires a routing and wavelength
assignment (RWA) process. From a path computation perspective,
wavelength assignment is the process of determining which wavelength
can be used on each hop of a path and forms an additional routing
constraint to optical light path computation.
Status of this Memo
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This Internet-Draft will expire on August 26, 2013.
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Table of Contents
1. Terminology....................................................3
2. Requirements Language..........................................3
3. Introduction...................................................3
4. Encoding of a RWA Path Request.................................6
4.1. Wavelength Assignment (WA) Object.........................6
4.2. Wavelength Restriction Constraint TLV.....................8
4.2.1. Link Identifier sub-TLV.............................11
4.2.2. Wavelength Restriction Field sub-TLV................12
4.3. Signal processing capability restrictions................12
4.3.1. Signal Processing Exclusion XRO Sub-Object..........13
4.3.2. IRO sub-object: signal processing inclusion.........14
5. Encoding of a RWA Path Reply..................................14
5.1. Error Indicator..........................................15
5.2. NO-PATH Indicator........................................15
6. Manageability Considerations..................................16
6.1. Control of Function and Policy...........................16
6.2. Information and Data Models, e.g. MIB module.............16
6.3. Liveness Detection and Monitoring........................16
6.4. Verifying Correct Operation..............................17
6.5. Requirements on Other Protocols and Functional Components17
6.6. Impact on Network Operation..............................17
7. Security Considerations.......................................17
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8. IANA Considerations...........................................17
9. Acknowledgments...............................................17
10. References...................................................18
10.1. Informative References..................................18
11. Contributors.................................................20
Authors' Addresses...............................................21
Intellectual Property Statement..................................21
Disclaimer of Validity...........................................22
1. Terminology
This document uses the terminology defined in [RFC4655], and
[RFC5440].
2. 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 [RFC2119].
3. Introduction
[RFC4655] defines the PCE based Architecture and explains how a Path
Computation Element (PCE) may compute Label Switched Paths (LSP) in
Multiprotocol Label Switching Traffic Engineering (MPLS-TE) and
Generalized MPLS (GMPLS) networks at the request of Path Computation
Clients (PCCs). A PCC is said to be any network component that
makes such a request and may be, for instance, an Optical Switching
Element within a Wavelength Division Multiplexing (WDM) network.
The PCE, itself, can be located anywhere within the network, and may
be within an optical switching element, a Network Management System
(NMS) or Operational Support System (OSS), or may be an independent
network server.
The PCE communications Protocol (PCEP) is the communication protocol
used between PCC and PCE, and may also be used between cooperating
PCEs. [RFC4657] sets out the common protocol requirements for PCEP.
Additional application-specific requirements for PCEP are deferred
to separate documents.
This document provides the PCEP extensions for the support of
Routing and Wavelength Assignment (RWA) in Wavelength Switched
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Optical Networks (WSON) based on the requirements specified in [PCE-
RWA].
WSON refers to WDM based optical networks in which switching is
performed selectively based on the wavelength of an optical signal.
In this document, it is assumed that wavelength converters require
electrical signal regeneration. Consequently, WSONs can be
transparent (A transparent optical network is made up of optical
devices that can switch but not convert from one wavelength to
another, all within the optical domain) or translucent (3R
regenerators are sparsely placed in the network).
A LSC Label Switched Path (LSP) may span one or several transparent
segments, which are delimited by 3R regenerators (typically with
electronic regenerator and optional wavelength conversion). Each
transparent segment or path in WSON is referred to as an optical
path. An optical path may span multiple fiber links and the path
should be assigned the same wavelength for each link. In such case,
the optical path is said to satisfy the wavelength-continuity
constraint. Figure 1 illustrates the relationship between a LSC LSP
and transparent segments (optical paths).
+---+ +-----+ +-----+ +-----+ +-----+
| |I1 | | | | | | I2| |
| |o------| |-------[(3R) ]------| |--------o| |
| | | | | | | | | |
+---+ +-----+ +-----+ +-----+ +-----+
[X LSC] [LSC LSC] [LSC LSC] [LSC X] SwCap
<-------> <-------> <-----> <------->
<-----------------------><---------------------->
Transparent Segment Transparent Segment
<------------------------------------------------->
LSC LSP
Figure 1 Illustration of a LSC LSP and transparent segments
Note that two optical paths within a WSON LSP need not operate on
the same wavelength (due to the wavelength conversion capabilities).
Two optical paths that share a common fiber link cannot be assigned
the same wavelength. To do otherwise would result in both signals
interfering with each other. Note that advanced additional
multiplexing techniques such as polarization based multiplexing are
not addressed in this document since the physical layer aspects are
not currently standardized. Therefore, assigning the proper
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wavelength on a lightpath is an essential requirement in the optical
path computation process.
When a switching node has the ability to perform wavelength
conversion, the wavelength-continuity constraint can be relaxed, and
a LSC Label Switched Path (LSP) may use different wavelengths on
different links along its route from origin to destination. It is,
however, to be noted that wavelength converters may be limited due
to their relatively high cost, while the number of WDM channels that
can be supported in a fiber is also limited. As a WSON can be
composed of network nodes that cannot perform wavelength conversion,
nodes with limited wavelength conversion, and nodes with full
wavelength conversion abilities, wavelength assignment is an
additional routing constraint to be considered in all lightpath
computation.
For example, within a translucent WSON, a LSC LSP may be established
between interfaces I1 and I2, spanning 2 transparent segments
(optical paths) where the wavelength continuity constraint applies
(i.e. the same unique wavelength MUST be assigned to the LSP at each
TE link of the segment). If the LSC LSP induced a Forwarding
Adjacency / TE link, the switching capabilities of the TE link would
be [X X] where X < LSC (PSC, TDM, ...).
This document aligns with GMPLS extensions for PCEP [PCEP-GMPLS] for
generic property such as label, label-set and label assignment
noting that wavelength is a type of label. Wavelength restrictions
and constraints are also formulated in terms of labels per [GEN-
ENCODE].
The optical modulation properties, which are also referred to as
signal compatibility, are already considered in signaling in [RWA-
Encode] and [WSON-OSPF]. In order to improve the signal quality and
limit some optical effects several advanced modulation processing
are used. Those modulation properties contribute not only to optical
signal quality checks but also constrain the selection of sender and
receiver, as they should have matching signal processing
capabilities. This document includes signal compatibility constraint
as part of RWA path computation. That is, the signal processing
capabilities (e.g., modulation and FEC) must be compatible between
the sender and the receiver of the optical path across all optical
elements.
This document, however, does not address optical impairments as part
of RWA path computation. See [WSON-Imp] and [RSVP-Imp] for more
information on optical impairments and GMPLS.
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4. Encoding of a RWA Path Request
Figure 2 shows one typical PCE based implementation, which is
referred to as Combined Process (R&WA). With this architecture, the
two processes of routing and wavelength assignment are accessed via
a single PCE. This architecture is the base architecture from which
the requirements have been specified in [PCE-RWA] and the PCEP
extensions that are going to be specified in this document based on
this architecture.
+----------------------------+
+-----+ | +-------+ +--+ |
| | | |Routing| |WA| |
| PCC |<----->| +-------+ +--+ |
| | | |
+-----+ | PCE |
+----------------------------+
Figure 2 Combined Process (R&WA) architecture
4.1. Wavelength Assignment (WA) Object
The current RP object is used to indicate routing related
information in a new path request per [RFC5440]. Since a new RWA
path request involves both routing and wavelength assignment, the
wavelength assignment related information in the request SHOULD be
coupled in the path request.
Wavelength allocation can be performed by the PCE by different
means:
(a) By means of Explicit Label Control, in the sense that one (or
two) allocated labels MAY appear after an interface route subobject.
(b) By means of a Label Set, containing one or more allocated Labels,
provided by the PCE.
Option (b) allows distributed label allocation (performed during
signaling) to complete wavelength assignment.
Additionally, given a range of potential labels to allocate, the
request SHOULD convey the heuristic / mechanism to the allocation.
The format of a PCReq message after incorporating the WA object is
as follows:
<PCReq Message> ::= <Common Header>
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[<svec-list>]
<request-list>
Where:
<request-list>::=<request>[<request-list>]
<request>::= <RP>
<ENDPOINTS>
<WA>
[other optional objects...]
If WA object is present in the request, the WA object MUST be
encoded after the ENDPOINTS object.
The format of the Wavelength Assignment (WA) object body is as
follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | O |M|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Optional TLVs //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3 WA Object
o Flags (32 bits)
The following new flags SHOULD be set
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M (Mode - 1 bit): M bit is used to indicate the mode of
wavelength assignment. When M bit is set to 1, this indicates
that the label assigned by the PCE must be explicit. That is,
the selected way to convey the allocated wavelength is by means
of Explicit Label Control (ELC) [RFC4003] for each hop of a
computed LSP. Otherwise, the label assigned by the PCE needs
not be explicit (i.e., it can be suggested in the form of label
set objects in the corresponding response, to allow distributed
WA. In such case, the PCE MUST return a Label Set object as
described in Section 2.2 of [Gen-Encode] in the response.
O (Order - 3 bits): O bit is used to indicate the wavelength
assignment constraint in regard to the order of wavelength
assignment to be returned by the PCE. This case is only applied
when M bit is set to "explicit." The following indicators
should be defined:
000 - Reserved
001 - Random Assignment
010 - First Fit (FF) in descending Order
011 - First Fit (FF) in ascending Order
100 - Last Fit (LF) in ascending Order
101 - Last Fit (LF) in descending Order
110 - Unspecified
111 - Reserved
4.2. Wavelength Restriction Constraint TLV
For any request that contains a wavelength assignment, the requester
(PCC) MUST be able to specify a restriction on the wavelengths to be
used. This restriction is to be interpreted by the PCE as a
constraint on the tuning ability of the origination laser
transmitter or on any other maintenance related constraints. Note
that if the LSP LSC spans different segments, the PCE MUST have
mechanisms to know the tunability restrictions of the involved
wavelength converters / regenerators, e.g. by means of the TED
either via IGP or NMS. Even if the PCE knows the tunability of the
transmitter, the PCC MUST be able to apply additional constraints to
the request.
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[Ed note: Which PCEP Object will home this TLV is yet to be
determined. Since this involves the end-point, The END-POINTS Object
might be a good candidate to encode this TLV, which will be provided
in a later revision.]
[Ed note: The current encoding assumes that tunability restriction
applied to link-level.]
The TLV type is TBD, recommended value is TBD. This TLV MAY appear
more than once to be able to specify multiple restrictions.
The TLV data is defined as follows:
<Wavelength Restriction Constraint> ::=
<Action> <Format> <Reserved>
(<Link Identifiers> <Wavelength Restriction>)...
Where
<Link Identifiers> ::=
<Unnumbered IF ID> | <IPV4 Address> | <IPV6 Address>
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action | Format | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Identifiers |
| . . . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Wavelength Restriction Field |
// . . . . //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Figure 4 Wavelength Restriction
o Action: 8 bits
0 - Inclusive List indicates that one or more link identifiers
are included in the Link Set. Each identifies a separate link
that is part of the set.
1 - Inclusive Range indicates that the Link Set defines a
range of links. It contains two link identifiers. The first
identifier indicates the start of the range (inclusive). The
second identifier indicates the end of the range (inclusive).
All links with numeric values between the bounds are
considered to be part of the set. A value of zero in either
position indicates that there is no bound on the corresponding
portion of the range. Note that the Action field can be set to
0 when unnumbered link identifier is used.
Note that "interfaces" such as those discussed in the Interfaces MIB
[RFC2863] are assumed to be bidirectional.
o Format: The format of the link identifier (8 bits)
0 -- Unnumbered Link Identifier
1 -- Local Interface IPv4 Address
2 -- Local Interface IPv6 Address
Others TBD.
Note that all link identifiers in the same list must be of the same
type.
o Reserved: Reserved for future use (16 bits)
o Link Identifiers: Identifies each link ID for which restriction
is applied. The length is dependent on the link format. See the
following section for Link Identifier encoding.
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4.2.1. Link Identifier sub-TLV
The link identifier field can be an IPv4, IPv6 or unnumbered
interface ID.
<Link Identifier> ::=
<IPV4 Address> | <IPV6 Address> | <Unnumbered IF ID>
The encoding of each case is as follows:
IPv4 prefix Sub-TLV
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 = 1 | IPv4 address (4 bytes) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 address (continued) | Prefix Length | Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IPv6 prefix Sub-TLV
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 = 2 | IPv6 address (16 bytes) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 address (continued) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 address (continued) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 address (continued) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 address (continued) | Prefix Length | Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Unnumbered Interface ID Sub-TLV
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
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 4 | Reserved | Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TE Node ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Interface ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
4.2.2. Wavelength Restriction Field sub-TLV
The Wavelength Restriction Field of the wavelength restriction TLV
is encoded as a Label Set field as specified in [GEN-Encode] section
2.2, as shown below, with base label encoded as a 32 bit LSC label,
defined in [RFC6205]. See [RFC6205] for a description of Grid, C.S,
Identifier and n, as well as [GEN-Encode] for the details of each
action.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Action| Num Labels | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Grid | C.S | Identifier | n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Additional fields as necessary per action |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
4.3. Signal processing capability restrictions
Path computation for WSON include the check of signal processing
capabilities, those capability MAY be provided by the IGP, however
this is not a MUST. Moreover, a PCC should be able to indicate
additional restrictions for those signal compatibility, either on
the endpoint or any given link.
The supported signal processing capabilities are the one described
in [RWA-Info]:
Optical Interface Class List
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Bit rate
Client signal
The Bit-rate restriction is already expressed in [PCEP-GMPLS] in the
GENERALIZED-BANDWIDTH object.
The client signal information can be expressed using the REQ-ADAP-
CAP object from the [PCEP-Layer].
In order to support the Optical Interface Class information a new
TLV are introduced as endpoint-restriction in the END-POINTS type
Generalized endpoint:
Optical Interface Class List TLV
The END-POINTS type generalized endpoint is extended as follow:
<endpoint-restrictions> ::= <LABEL-REQUEST>
<label-restriction-list>
[<signal-compatibility-restriction>...]
Where
signal-compatibility-restriction ::=
<Optical Interface Class List>
The encoding for Optical Interface Class List is described in
Section 5.2 of [RWA-Encode].
4.3.1. Signal Processing Exclusion XRO Sub-Object
The PCC/PCE should be able to exclude particular types of signal
processing along the path in order to handle client restriction or
multi-domain path computation.
In order to support the exclusion a new XRO sub-object is defined:
the signal processing exclusion:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X| Type = X | Length | Reserved | Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| sub-sub objects |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5 Signaling Processing XRO Sub-Object
The Attribute field indicates how the exclusion sub-object is to be
interpreted. The Attribute can only be 0 (Interface) or 1 (Node).
The sub-sub objects are encoded as in RSVP signaling definition
[WSON-Sign].
4.3.2. IRO sub-object: signal processing inclusion
Similar to the XRO sub-object the PCC/PCE should be able to include
particular types of signal processing along the path in order to
handle client restriction or multi-domain path computation.
This is supported by adding the sub-object "processing" defined for
ERO in [WSON-Sign] to the PCEP IRO object.
5. Encoding of a RWA Path Reply
The ERO is used to encode the path of a TE LSP through the network.
The ERO is carried within a given path of a PCEP response, which is
in turn carried in a PCRep message to provide the computed TE LSP if
the path computation was successful. The preferred way to convey the
allocated wavelength is by means of Explicit Label Control (ELC)
[RFC4003].
In order to encode wavelength assignment, the Wavelength Assignment
(WA) Object needs to be employed to be able to specify wavelength
assignment. Since each segment of the computed optical path is
associated with wavelength assignment, the WA Object should be
aligned with the ERO object.
Encoding details will be provided further revisions and will be
aligned as much as possible with [WSON-Sign] and [LSPA-ERO]
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5.1. Error Indicator
To indicate errors associated with the RWA request, a new Error Type
(TDB) and subsequent error-values are defined as follows for
inclusion in the PCEP-ERROR Object:
A new Error-Type (TDB) and subsequent error-values are defined as
follows:
Error-Type=TBD; Error-value=1: if a PCE receives a RWA request
and the PCE is not capable of processing the request due to
insufficient memory, the PCE MUST send a PCErr message with a
PCEP-ERROR Object (Error-Type=TDB) and an Error-value(Error-
value=1). The PCE stops processing the request. The
corresponding RWA request MUST be cancelled at the PCC.
Error-Type=TBD; Error-value=2: if a PCE receives a RWA request
and the PCE is not capable of RWA computation, the PCE MUST
send a PCErr message with a PCEP-ERROR Object (Error-Type=15)
and an Error-value (Error-value=2). The PCE stops processing
the request. The corresponding RWA computation MUST be
cancelled at the PCC.
5.2. NO-PATH Indicator
To communicate the reason(s) for not being able to find RWA for the
path request, the NO-PATH object can be used in the PCRep message.
The format of the NO-PATH object body is defined in [RFC5440]. The
object may contain a NO-PATH-VECTOR TLV to provide additional
information about why a path computation has failed.
Two new bit flags are defined to be carried in the Flags field in
the NO-PATH-VECTOR TLV carried in the NO-PATH Object.
Bit TDB: When set, the PCE indicates no feasible route was
found that meets all the constraints associated with RWA.
Bit TDB: When set, the PCE indicates that no wavelength was
assigned to at least one hop of the route in the response.
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Bit TDB: When set, the PCE indicate that no path was found
satisfying the signal compatibility constraints.
6. Manageability Considerations
Manageability of WSON Routing and Wavelength Assignment (RWA) with
PCE must address the following considerations:
6.1. Control of Function and Policy
In addition to the parameters already listed in Section 8.1 of
[PCEP], a PCEP implementation SHOULD allow configuring the following
PCEP session parameters on a PCC:
The ability to send a WSON RWA request.
In addition to the parameters already listed in Section 8.1 of
[PCEP], a PCEP implementation SHOULD allow configuring the following
PCEP session parameters on a PCE:
The support for WSON RWA.
A set of WSON RWA specific policies (authorized sender,
request rate limiter, etc).
These parameters may be configured as default parameters for any
PCEP session the PCEP speaker participates in, or may apply to a
specific session with a given PCEP peer or a specific group of
sessions with a specific group of PCEP peers.
6.2. Information and Data Models, e.g. MIB module
Extensions to the PCEP MIB module defined in [PCEP-MIB] should be
defined, so as to cover the WSON RWA information introduced in this
document. A future revision of this document will list the
information that should be added to the MIB module.
6.3. Liveness Detection and Monitoring
Mechanisms defined in this document do not imply any new liveness
detection and monitoring requirements in addition to those already
listed in section 8.3 of [RFC5440].
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6.4. Verifying Correct Operation
Mechanisms defined in this document do not imply any new
verification requirements in addition to those already listed in
section 8.4 of [RFC5440]
6.5. Requirements on Other Protocols and Functional Components
The PCE Discovery mechanisms ([RFC5089] and [RFC5088]) may be used
to advertise WSON RWA path computation capabilities to PCCs.
6.6. Impact on Network Operation
Mechanisms defined in this document do not imply any new network
operation requirements in addition to those already listed in
section 8.6 of [RFC5440].
7. Security Considerations
This document has no requirement for a change to the security models
within PCEP [PCEP]. However the additional information distributed
in order to address the RWA problem represents a disclosure of
network capabilities that an operator may wish to keep private.
Consideration should be given to securing this information.
8. IANA Considerations
A future revision of this document will present requests to IANA for
codepoint allocation.
9. Acknowledgments
The authors would like to thank Adrian Farrel for many helpful
comments that greatly improved the contents of this draft.
This document was prepared using 2-Word-v2.0.template.dot.
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10. References
10.1. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Functional Description", RFC 3471,
January 2003.
[RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Resource ReserVation Protocol-
Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
January 2003.
[RFC3477] Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links
in Resource ReSerVation Protocol - Traffic Engineering
(RSVP-TE)", RFC 3477, January 2003.
[RFC4003] Berger, L., "GMPLS Signaling Procedure for Egress Control",
RFC 4003, February 2005.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4655, August 2006.
[RFC4657] Ash, J. and J. Le Roux, "Path Computation Element (PCE)
Communication Protocol Generic Requirements", RFC 4657,
September 2006.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) communication Protocol", RFC 5440, March
2009.
[PCEP-GMPLS] Margaria, et al., "PCEP extensions for GMPLS", draft-
ietf-pce-gmpls-pcep-extensions, work in progress.
[LSPA-ERO] Margaria, et al., "LSP Attribute in ERO", draft-margaria-
ccamp-lsp-attribute-ero, work in progress.
[PCEP-Layer] Oki, Takeda, Le Roux, and Farrel, "Extensions to the
Path Computation Element communication Protocol (PCEP) for
Inter-Layer MPLS and GMPLS Traffic Engineering", draft-
ietf-pce-inter-layer-ext, work in progress.
Lee & Casellas Expires September26,2013 [Page 18]
Internet-Draft PCEP Extension for WSON RWA March 2013
[RFC6163] Lee, Y. and Bernstein, G. (Editors), and W. Imajuku,
"Framework for GMPLS and PCE Control of Wavelength
Switched Optical Networks", RFC 6163, March 2011.
[PCE-RWA] Lee, Y., et. al., "PCEP Requirements for WSON Routing and
Wavelength Assignment", draft-ietf-pce-wson-routing-
wavelength, work in progress.
[RFC6205] Tomohiro, O. and D. Li, "Generalized Labels for Lambda-
Switching Capable Label Switching Routers", RFC 6205,
January, 2011.
[WSON-Sign] Bernstein et al,"Signaling Extensions for Wavelength
Switched Optical Networks", draft-ietf-ccamp-wson-
signaling, work in progress.
[WSON-OSPF] Lee and Bernstein,"OSPF Enhancement for Signal and
Network Element Compatibility for Wavelength Switched
Optical Networks",draft-ietf-ccamp-wson-signal-
compatibility-ospf, work in progress.
[RWA-Info] Bernstein and Lee, "Routing and Wavelength Assignment
Information Model for Wavelength Switched Optical
Networks",draft-ietf-ccamp-rwa-info, work in progress.
[RWA-Encode]Bernstein and Lee, "Routing and Wavelength Assignment
Information Encoding for Wavelength Switched Optical
Networks",draft-ietf-ccamp-rwa-wson-encode, work in
progress.
[GEN-Encode] Bernstein and Lee, "General Network Element Constraint
Encoding for GMPLS Controlled Networks",draft-ietf-ccamp-
general-constraint-encode, work in progress.
[WSON-Imp] Y. Lee, G. Bernstein, D. Li, G. Martinelli, "A Framework
for the Control of Wavelength Switched Optical Networks
(WSON) with Impairments", draft-ietf-ccamp-wson-
impairments, work in progress.
[RSVP-Imp] agraz, "RSVP-TE Extensions in Support of Impairment Aware
Routing and Wavelength Assignment in Wavelength Switched
Optical Networks WSONs)", draft-agraz-ccamp-wson-
impairment-rsvp, work in progress.
[OSPF-Imp] Bellagamba, et al., "OSPF Extensions for Wavelength
Switched Optical Networks (WSON) with Impairments",draft-
eb-ccamp-ospf-wson-impairments, work in progress.
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11. Contributors
Lee & Casellas Expires September26,2013 [Page 20]
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Authors' Addresses
Young Lee, Editor
Huawei Technologies
1700 Alma Drive, Suite 100
Plano, TX 75075, USA
Phone: (972) 509-5599 (x2240)
Email: leeyoung@huawei.com
Ramon Casellas, Editor
CTTC PMT Ed B4 Av. Carl Friedrich Gauss 7
08860 Castelldefels (Barcelona)
Spain
Phone: (34) 936452916
Email: ramon.casellas@cttc.es
Fatai Zhang
Huawei Technologies
Email: zhangfatai@huawei.com
Cyril Margaria
Nokia Siemens Networks
St Martin Strasse 76
Munich, 81541
Germany
Phone: +49 89 5159 16934
Email: cyril.margaria@nsn.com
Oscar Gonzalez de Dios
Telefonica Investigacion y Desarrollo
C/ Emilio Vargas 6
Madrid, 28043
Spain
Phone: +34 91 3374013
Email: ogondio@tid.es
Greg Bernstein
Grotto Networking
Fremont, CA, USA
Phone: (510) 573-2237
Email: gregb@grotto-networking.com
Intellectual Property Statement
Lee & Casellas Expires September26,2013 [Page 21]
Internet-Draft PCEP Extension for WSON RWA March 2013
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Lee & Casellas Expires September26,2013 [Page 22]
