Internet DRAFT - draft-palle-pce-controller-labeldb-sync
draft-palle-pce-controller-labeldb-sync
PCE Working Group U. Palle
Internet-Draft D. Dhody
Intended status: Standards Track S. Karunanithi
Expires: September 5, 2018 Huawei Technologies
March 4, 2018
LABEL-DB Synchronization Procedures for a PCE as a central
controller(PCECC)
draft-palle-pce-controller-labeldb-sync-03
Abstract
PCE as a central controller specifies the procedures and PCEP
protocol extensions where LSPs are calculated/setup/initiated and
label forwarding entries are downloaded through a centralized PCE
server to each network devices along the LSP path while leveraging
the existing PCE technologies as much as possible.
Labels downloaded to forwarding entries requires a reliable
synchronization mechanism between the path computation clients (PCCs)
and the PCE. The basic mechanism for label database (LABEL-DB
synchronization is part of the PCE as a central controller
specification. This document presents motivations for optimizations
to the LABEL-DB synchronization and the corresponding PCEP procedures
and extensions.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
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."
This Internet-Draft will expire on September 5, 2018.
Palle, et al. Expires September 5, 2018 [Page 1]
Internet-Draft LABEL-DB-SYNC March 2018
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. LABEL-DB Synchronization . . . . . . . . . . . . . . . . . . 3
3. Optimizations for LABEL-DB Synchronization . . . . . . . . . 4
3.1. LABEL-DB Synchronization Avoidance Procedure . . . . . . 4
3.2. Incremental LABEL-DB Synchronization Procedure . . . . . 8
4. PCEP Extensions . . . . . . . . . . . . . . . . . . . . . . . 10
4.1. Extension of SRP object . . . . . . . . . . . . . . . . . 10
4.2. Extension of PCECC Capability sub-TLV . . . . . . . . . . 10
4.3. New LABEL-DB-VERSION TLV . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
5.1. PCEP TLV Type Indicators . . . . . . . . . . . . . . . . 12
5.2. PCECC-CAPABILITY sub-TLV . . . . . . . . . . . . . . . . 12
6. Manageability Considerations . . . . . . . . . . . . . . . . 12
6.1. Control of Function and Policy . . . . . . . . . . . . . 12
6.2. Information and Data Models . . . . . . . . . . . . . . . 12
6.3. Liveness Detection and Monitoring . . . . . . . . . . . . 12
6.4. Verify Correct Operations . . . . . . . . . . . . . . . . 12
6.5. Requirements On Other Protocols . . . . . . . . . . . . . 13
6.6. Impact On Network Operations . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References . . . . . . . . . . . . . . . . . . 13
9.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
Palle, et al. Expires September 5, 2018 [Page 2]
Internet-Draft LABEL-DB-SYNC March 2018
1. Introduction
[I-D.zhao-pce-pcep-extension-for-pce-controller] specify the
procedures and PCEP protocol extensions for using the PCE as the
central controller [RFC8283] and user cases where LSPs are
calculated/setup/initiated/downloaded through extending the existing
PCE architectures and PCEP.
[I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr] specifies reliable
synchronization mechanism between the path computation clients (PCCs)
and the PCECC.
This draft specify the optimizations for LABEL-DB synchronization and
the corresponding PCEP procedures and extensions.
[Important Note - [I-D.zhao-pce-pcep-extension-for-pce-controller]
defined new messages for label download and cleanup. The authors and
WG also debated on the use of existing PCEP messages. The appendix
of the document includes the details related to use of existing
messages. This document is related to new messages as a new
procedure for Label DB sync was defined. In case existing messages
are used, some modifications needs to be made to the existing LSP-DB
synchronization mechanism to also handle the label synchronization.
These details are not present in the document at this stage. ]
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. LABEL-DB Synchronization
PCECC MUST maintains the LABEL-DB for each PCEP session separately.
The purpose of LABEL-DB synchronization is to make sure that the
PCECC's view of LABEL-DB matches with the PCC's LABEL-DB. The LABEL-
DB synchronization MUST be performed from PCECC to PCC immediately
after the LSP state synchronization. [RFC8231] describes the basic
mechanism for LSP state synchronization. [RFC8233] describes the
optimizations for LSP state synchronization.
Full LABEL-DB synchronization performed from PCECC to PCC on Initial
session UP or every session flap is described in
[I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr].
Palle, et al. Expires September 5, 2018 [Page 3]
Internet-Draft LABEL-DB-SYNC March 2018
Providing an Optimizations for LABEL-DB synchronization can result in
significant savings in both control-plane data exchanges and the time
it takes for the PCC to become fully operational.
Optimizations for LABEL-DB synchronization describes the need that
both PCEP speakers support label database version capability and
maintain label database version for each session. See Section 3 for
detail procedures.
[Editor's Note: [I-D.zhao-pce-pcep-extension-for-pce-controller]
defines new messages PCLabelUpd and PCLabelRpt. Questions where
raised on the need for the new messages. Further appendix in
[I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr] describes how the
existing messages can be extended to add this functionality. WG
needs to decide the final direction i.e. new specific messages are
needed or existing PCEP messages can be extended. The optimization
procedure would need to be modified based on the above decision.]
3. Optimizations for LABEL-DB Synchronization
This section add some of the optimization mechanisms for LABEL-DB
synchronization. By default, the full LABEL-DB synchronization is
performed.
3.1. LABEL-DB Synchronization Avoidance Procedure
The LABEL-DB synchronization MAY be skipped following a PCEP session
restart if there is no change in the LABEL-DB of the session at
PCECC, during the period prior to session re-initialization. To be
able to make this determination, labels must be exchanged and
maintained by both PCECC and PCC during normal operation. This is
accomplished by keeping track of the changes to the label database,
using a version tracking field called the Label Database Version
Number.
The Label Database Version Number, carried in LABEL-DB-VERSION TLV
(see Section 4.3), is owned by a PCECC and it MUST be incremented by
1 for each successive change in the PCECC's label database. The
Label Database Version Number MUST start at 1 and may wrap around.
Values 0 and 0xFFFFFFFFFFFFFFFF are reserved. If either of the two
values are used during LABEL-DB synchronization, the PCC speaker
receiving this node should send back a PCErr with Error-type TBD1
Error-value 3 'Received an invalid Label Database Version Number',
and close the PCEP session. Operations that trigger a change to the
Label database include an addition or deletion of labels that would
trigger a label update to the PCC.
Palle, et al. Expires September 5, 2018 [Page 4]
Internet-Draft LABEL-DB-SYNC March 2018
LABEL-DB synchronization avoidance is advertised on a PCEP session
during session startup using the INCLUDE-LABEL-DB-VERSION (I) bit in
the PCECC capability sub-TLV (see Section 4.2). The PCEP peer MAY
include the SPEAKER-ENTITY-ID TLV described in [RFC8233] in the OPEN
message to identify the peer in case of IP address change.
If both PCEP speakers set the I flag in the OPEN object's PCECC
Capability sub-TLV to 1, the PCECC MUST include the LABEL-DB-VERSION
TLV in each LABEL object of the PCLabelUpd message. If the LABEL-DB-
VERSION TLV is missing in a PCLabelUpd message, the PCC will generate
an error with Error-Type 6 (mandatory object missing) and Error-Value
TBD2 'LABEL-DB-VERSION TLV missing' and close the session. If LABEL-
DB synchronization avoidance has not been enabled on a PCEP session,
the PCECC SHOULD NOT include the LABEL-DB-VERSION TLV in the LABEL
Object and the PCC SHOULD ignore it were it to receive one.
If a PCC's label database survived the restart of a PCEP session, the
PCC will include the LABEL-DB-VERSION TLV in its OPEN object, and the
TLV will contain the last Label Database Version Number received on
an Label Update from the PCECC in the previous PCEP session. If a
PCECC's Label Database survived the restart of a PCEP session, the
PCECC will include the LABEL-DB-VERSION TLV in its OPEN object and
the TLV will contain the latest Label Database Version Number. If a
PCEP speaker's label database did not survive the restart of a PCEP
session, the PCEP speaker MUST NOT include the LABEL-DB-VERSION TLV
in the OPEN object.
If both PCEP speakers include the LABEL-DB-VERSION TLV in the OPEN
Object and the TLV values match, the PCECC MAY skip LABEL-DB
synchronization. Otherwise, the PCECC MUST perform full LABEL-DB
synchronization ([I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr]) or incremental
LABEL-DB synchronization (see Section 3.2) to the PCC, In case, the
PCECC attempts to skip LABEL-DB synchronization, by setting the SYNC
Flag to 0 on the first Label Update from the PCECC, the PCC MUST send
back a PCErr with Error-type TBD1 (Label Database Synchronization
Error) and Error-value 4(Label Database Version mismatch), and close
the PCEP session.
If LABEL-DB synchronization is required, then prior to completing the
initialization phase, the PCC MUST mark any labels in the label
database that were previously updated by the PCECC as stale. When
the PCECC updates a label during LABEL-DB synchronization, if the
label already exists in the label database, the PCC MUST update the
label database and clear the stale marker from the label. When it
has finished LABEL-DB synchronization, the PCECC MUST immediately
send an end of synchronization marker. The end of synchronization
marker is a Path Computation Label Update (PCLabelUpd) message with a
Palle, et al. Expires September 5, 2018 [Page 5]
Internet-Draft LABEL-DB-SYNC March 2018
SRP object containing the SYNC flag set to 0 (see Section 4.1) and
Label as 0 in the LABEL object. The LABEL-DB-VERSION TLV MUST be
included in this PCLabelUpd message. On receiving this Label Update,
the PCC MUST report all the labels in the label database that are
still marked as stale to PCECC.
Note that a PCECC/PCC MAY force LABEL-DB synchronization by not
including the LABEL-DB-VERSION TLV in its OPEN object.
Figure 1 shows an example sequence where the LABEL-DB synchronization
is skipped.
+-+-+-+ +-+-+
|PCECC| |PCC|
+-+-+-+ +-+-+
| ,----Open---|
| / DBv=35 |
|--Open--, / I=1 |
| DBv=35 \ / |
| I=1 \ / |
| \/ |
| /\ |
| / `------------->| (OK to skip sync)
(Skip sync) |<--------` |
| . |
| . |
| . |
| |
|--PCLabelUpd,DBv=36,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=37,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=38,SYNC=0-->|
| |
Figure 1: LABEL-DB synchronization Skipped
Figure 2 shows an example sequence where the LABEL-DB synchronization
is performed due to label database version mismatch during the PCEP
session setup. Note that the same LABEL-DB synchronization sequence
would happen if either the PCC or the PCECC would not include the
LABEL- DB-VERSION TLV in their respective Open messages.
Palle, et al. Expires September 5, 2018 [Page 6]
Internet-Draft LABEL-DB-SYNC March 2018
+-+-+-+ +-+-+
|PCECC| |PCC|
+-+-+-+ +-+-+
| ,----Open---|
| / DBv=35 |
|--Open--, / I=1 |
| DBv=39 \ / |
| I=1 \ / |
| \/ |
| /\ |
| / `------------->| (Expect sync)
(Do sync) |<--------` |
| |
|--PCLabelUpd,DBv=39,SYNC=1-->| (Sync start)
| . |
| . |
| . |
|--PCLabelUpd,DBv=39,SYNC=0-->| (Sync done)
| . |
| . |
| . |
|--PCLabelUpd,DBv=40,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=41,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=42,SYNC=0-->|
| |
Figure 2: LABEL-DB synchronization Performed
Figure 3 shows an example sequence where the LABEL-DB synchronization
is skipped, but because one or both PCEP speakers set the I Flag to
0, the PCECC does not send LABEL-DB-VERSION TLVs in subsequent
PCLabelUpd messages to the PCC. If the current PCEP session
restarts, the PCEP speakers will have to perform full LABEL-DB
synchronization, since the PCC does not know the PCECC's latest Label
Database Version Number information.
Palle, et al. Expires September 5, 2018 [Page 7]
Internet-Draft LABEL-DB-SYNC March 2018
+-+-+-+ +-+-+
|PCECC| |PCC|
+-+-+-+ +-+-+
| ,----Open---|
| / DBv=43 |
|--Open--, / I=0 |
| DBv=43 \ / |
| I=0 \ / |
| \/ |
| /\ |
| / `------------->| (OK to skip sync)
(Skip sync) |<--------` |
| . |
| . |
| . |
|------PCLabelUpd,SYNC=0----->| (Regular
| | Label Update)
|------PCLabelUpd,SYNC=0----->| (Regular
| | Label Update)
|------PCLabelUpd,SYNC=0----->|
| |
Figure 3: LABEL-DB Synchronization Skipped, no LABEL-DB-VERSION TLVs
sent from PCECC
3.2. Incremental LABEL-DB Synchronization Procedure
If a PCC restarts and its label database survived, PCECC with
mismatched Label Database Version Number will send all their Labels
information (full LABEL-DB) to the PCC, even if only a small number
of changes happened. It can take a long time and consume large
communication channel bandwidth.
This section extends the idea to only synchronize the delta (changes)
in case of Label Database Version Number of both PCEP peers is non-
zero and mismatch.
If both PCEP speakers include the LABEL-DB-VERSION TLV in the OPEN
object and the LABEL-DB-VERSION TLV values match, the PCECC MAY skip
LABEL-DB synchronization. Otherwise, the PCECC MUST perform LABEL-DB
synchronization. Incremental label database synchronization
capability is advertised on a PCEP session during session startup
using the DELTA-LABEL-SYNC-CAPABILITY (D) bit in the capabilities TLV
(see Section 4.2). Instead of dumping full LABEL-DB to the PCC
again, the PCECC synchronizes the delta (changes) as described in
Figure 4 when D flag and I flag is set to 1 by both PCC and PCECC.
Other combinations of D and I flags setting by PCC and PCECC result
in full LABEL-DB synchronization procedure as described in
Palle, et al. Expires September 5, 2018 [Page 8]
Internet-Draft LABEL-DB-SYNC March 2018
[I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr]. The PCECC MAY force
a full LABEL-DB synchronization by setting the D flag to zero in the
OPEN message.
+-+-+-+ +-+-+
|PCECC| |PCC|
+-+-+-+ +-+-+
| ,----Open---|
| / DBv=35 |
|--Open--, / I=1 |
| DBv=39 \ / D=1 |
| I=1 \ / |
| \/ |
| /\ |
| / `------------->| (Expect Delta sync)
(Do sync)|<--------` |
(Delta) | |
| |
(Delta |--PCLabelUpd,DBv=39,SYNC=1-->|
Sync starts) | . |
| . |
| . |
| . |
|--PCLabelUpd,DBv=39,SYNC=0-->| (Sync done)
| |
| |
|--PCLabelUpd,DBv=40,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=41,SYNC=0-->| (Regular
| | Label Update)
|--PCLabelUpd,DBv=42,SYNC=0-->|
| |
Figure 4: Incremental Synchronization Procedure
As per Section 3.1, the Label Database Version Number is incremented
each time a change is made to the PCECC's label database. Each label
is associated with the DB version at the time of its addition. This
is needed to determine which label and what information needs to be
synchronized in incremental LABEL-DB synchronization.
It is not necessary for a PCECC to store a complete history of label
database change, but rather remember the labels (including label
addition and deletion) that happened between the PCEP session(s)
restart in order to carry out incremental LABEL-DB synchronization.
After the synchronization procedure finishes, the PCECC can dump this
Palle, et al. Expires September 5, 2018 [Page 9]
Internet-Draft LABEL-DB-SYNC March 2018
history information. In the example shown in Figure 4, the PCECC
needs to store the label changes that happened between DB Version 35
to 39 and synchronizes these changes only when performing incremental
label update. So a PCECC needs to remember at least the label
changes that happened after an existing PCEP session with a PCC goes
down to have any chance of doing incremental synchronization when the
session is re-established.
If a PCECC finds out it does not have sufficient information to
complete incremental synchronization after advertising incremental
LABEL-DB synchronization capability, it MUST send a PCErr with Error-
Type TBD1 and Error-Value 5 'A PCECC indicates to a PCC that it can
not complete the LABEL-DB synchronization' and terminate the session.
The PCECC SHOULD re-establish the session with the D bit set to 0 in
the OPEN message.
The other procedures and error checks remain unchanged from the
default LABEL-DB synchronization defined in
[I-D.zhao-pce-pcep-extension-for-pce-controller] and
[I-D.zhao-pce-pcep-extension-pce-controller-sr].
4. PCEP Extensions
4.1. Extension of SRP object
SRP object extension for SYNC flag to specify the LABEL-DB
synchronization operation is defined in
[I-D.zhao-pce-pcep-extension-for-pce-controller].
4.2. Extension of PCECC Capability sub-TLV
PCECC Capability sub-TLV is defined in
[I-D.zhao-pce-pcep-extension-for-pce-controller]. This draft defines
a new 'INCLUDE-LABEL-DB-VERSION' flag (I bit) to specify the label
database version capability and 'DELTA-LABEL-SYNC-CAPABILITY' to
specify the incremental label database synchronization capability.
The TLV format is as per [RFC5440]. The format of the PCECC
Capability sub-TLV is shown Figure 5:
Palle, et al. Expires September 5, 2018 [Page 10]
Internet-Draft LABEL-DB-SYNC March 2018
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=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags |D|I|S|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: PCECC Capability sub-TLV
I (INCLUDE-LABEL-DB-VERSION - 1 bit): if set to 1 by both PCEP
Speakers, the PCECC will include the LABEL-DB-VERSION TLV in each
LABEL Object.
D (DELTA-LABEL-SYNC-CAPABILITY - 1 bit): if set to 1 by a PCEP
speaker, it indicates that the PCEP speaker allows incremental
(delta) LABEL-DB synchronization.
4.3. New LABEL-DB-VERSION TLV
The Label Database Version Number (LABEL-DB-VERSION) TLV is an
optional TLV that MAY be included in the OPEN object and the LABEL
object.
The TLV format is as per [RFC5440]. The format of the LABEL-DB-
VERSION TLV is shown in the following figure:
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=[TBD3] | Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label Database Version Number |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: LABEL-DB-VERSION TLV format
The type of the TLV is [TBD3] and it has a fixed length of 8 octets.
The value contains a 64-bit unsigned integer, representing the Label
Database Version Number.
Palle, et al. Expires September 5, 2018 [Page 11]
Internet-Draft LABEL-DB-SYNC March 2018
5. IANA Considerations
5.1. PCEP TLV Type Indicators
IANA is requested to confirm the early allocation of the following
TLV Type Indicator values within the "PCEP TLV Type Indicators" sub-
registry of the PCEP Numbers registry, and to update the reference in
the registry to point to this document, when it is an RFC:
Value Meaning Reference
[TBD] LABEL-DB-VERSION TLV This document
5.2. PCECC-CAPABILITY sub-TLV
[I-D.zhao-pce-pcep-extension-for-pce-controller] defines the PCECC-
CAPABILITY sub-TLV and
[I-D.zhao-pce-pcep-extension-pce-controller-sr] extends this sub-TLV
to add PCECC-SR-CAPABILITY.
Requests that IANA creates a registry to manage the value of the new
PCECC-CAPABILITY sub-TLV's Flag field. IANA is requested to allocate
a new bits in the PCECC-CAPABILITY sub-TLV Flag Field registry, as
follows:
Bit Description Reference
TBD I (INCLUDE-LABEL-DB-VERSION ) This document
TBD D (DELTA-LABEL-SYNC-CAPABILITY) This document
6. Manageability Considerations
All manageability requirements and considerations listed in
[RFC5440], [RFC8231] and
[I-D.zhao-pce-pcep-extension-for-pce-controller] apply to PCEP
protocol extensions defined in this document. In addition,
requirements and considerations listed in this section apply.
6.1. Control of Function and Policy
6.2. Information and Data Models
6.3. Liveness Detection and Monitoring
6.4. Verify Correct Operations
Palle, et al. Expires September 5, 2018 [Page 12]
Internet-Draft LABEL-DB-SYNC March 2018
6.5. Requirements On Other Protocols
6.6. Impact On Network Operations
7. Security Considerations
The security considerations listed in [RFC8231] and
[I-D.zhao-pce-pcep-extension-for-pce-controller] apply to this
document as well. Securing the PCEP session using Transport Layer
Security (TLS) [RFC8253], as per the recommendations and best current
practices in [RFC7525], is RECOMMENDED.
8. Acknowledgements
This document borrows some of the structure and text from [RFC8253],
and would like to thanks the authors and contributors of the
document.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/info/rfc5440>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for Stateful PCE", RFC 8231,
DOI 10.17487/RFC8231, September 2017,
<https://www.rfc-editor.org/info/rfc8231>.
[I-D.zhao-pce-pcep-extension-for-pce-controller]
Zhao, Q., Li, Z., Dhody, D., Karunanithi, S., Farrel, A.,
and C. Zhou, "PCEP Procedures and Protocol Extensions for
Using PCE as a Central Controller (PCECC) of LSPs", draft-
zhao-pce-pcep-extension-for-pce-controller-06 (work in
progress), October 2017.
Palle, et al. Expires September 5, 2018 [Page 13]
Internet-Draft LABEL-DB-SYNC March 2018
9.2. Informative References
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <https://www.rfc-editor.org/info/rfc7525>.
[RFC8233] Dhody, D., Wu, Q., Manral, V., Ali, Z., and K. Kumaki,
"Extensions to the Path Computation Element Communication
Protocol (PCEP) to Compute Service-Aware Label Switched
Paths (LSPs)", RFC 8233, DOI 10.17487/RFC8233, September
2017, <https://www.rfc-editor.org/info/rfc8233>.
[RFC8253] Lopez, D., Gonzalez de Dios, O., Wu, Q., and D. Dhody,
"PCEPS: Usage of TLS to Provide a Secure Transport for the
Path Computation Element Communication Protocol (PCEP)",
RFC 8253, DOI 10.17487/RFC8253, October 2017,
<https://www.rfc-editor.org/info/rfc8253>.
[RFC8283] Farrel, A., Ed., Zhao, Q., Ed., Li, Z., and C. Zhou, "An
Architecture for Use of PCE and the PCE Communication
Protocol (PCEP) in a Network with Central Control",
RFC 8283, DOI 10.17487/RFC8283, December 2017,
<https://www.rfc-editor.org/info/rfc8283>.
[I-D.zhao-pce-pcep-extension-pce-controller-sr]
Zhao, Q., Li, Z., Dhody, D., Karunanithi, S., Farrel, A.,
and C. Zhou, "PCEP Procedures and Protocol Extensions for
Using PCE as a Central Controller (PCECC) of SR-LSPs",
draft-zhao-pce-pcep-extension-pce-controller-sr-01 (work
in progress), October 2017.
Authors' Addresses
Udayasree Palle
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: udayasreereddy@gmail.com
Palle, et al. Expires September 5, 2018 [Page 14]
Internet-Draft LABEL-DB-SYNC March 2018
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: dhruv.ietf@gmail.com
Satish Karunanithi
Huawei Technologies
Divyashree Techno Park, Whitefield
Bangalore, Karnataka 560066
India
EMail: satishk@huawei.com
Palle, et al. Expires September 5, 2018 [Page 15]