OSPF extension for priority allocation support in the PCE discovery
draft-wu-pce-discovery-priority-allocation-00
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Qin Wu | ||
| Last updated | 2013-07-15 | ||
| Stream | (None) | ||
| Formats | plain text xml htmlized pdfized bibtex | ||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-wu-pce-discovery-priority-allocation-00
PCE working group Q. Wu
Internet-Draft Huawei
Intended status: Standards Track July 15, 2013
Expires: January 16, 2014
OSPF extension for priority allocation support in the PCE discovery
draft-wu-pce-discovery-priority-allocation-00
Abstract
Each network domain may contain multiple PCE servers. It provides
redundancy to the PCCs in the event of a server failure. However
load balance decision is made by PCC,it doesn't enable real load
balance across the PCE servers if PCC still tries PCE one by one and
PCE doesn't indicate the load status to the PCC.
This document proposes new PCE discovery sub-TLV that can be
announced as attribute in the OSPF advertisement (defined in [RFC5088
]) to distribute priority information.
Status of this Memo
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This Internet-Draft will expire on January 16, 2014.
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to this document. Code Components extracted from this document must
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . . 4
3. PCE-ALLOCATION-PRIORITY Sub-TLV for PCE Load Balancing . . . . 5
3.1. Use of PCE-ALLOCATION-PRIORITY sub-TLV for PCE
discovery . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7
6. Normative References . . . . . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 9
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1. Introduction
Usually a single PCE server sits per domain in the nework. The PCE
server disseminates its address in the network using OSPF [RFC5088]
or ISIS [RFC5089] and the PCCs connect to it automatically. However
in some cases, each network domain may contain multiple PCE servers.
It provides redundancy to the PCCs in the event of a server failure.
However load balance decision is made by PCC,it doesn't enable real
load balance across the PCE servers if PCC still tries PCE one by one
and PCE doesn't indicate the load status to the PCC (e.g., the number
of incoming requests that have already targeted to the PCE).
This document proposes new PCE discovery TLV that can be announced as
attribute in the OSPF advertisement (defined in [RFC5088 ]) to
distribute priority information.
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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 RFC2119 [RFC2119].
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3. PCE-ALLOCATION-PRIORITY Sub-TLV for PCE Load Balancing
The PCE-Allocated-Priority sub-TLV is an optional sub-TLV used to
indicate allocated priority of each PCE. The format of the sub-TLVs
is identical to the TLV format used by the Traffic Engineering
Extensions to OSPF [RFC3630]. It MAY be present within the PCED TLV.
It MUST NOT be present more than once. If it appears more than once,
only the first occurrence is processed and any others MUST be
ignored.
The value field of the PCE-ALLOCATED-PRIORITY sub-TLV is expressed as
32-bit unsigned integer value..
The format of the PCE-ALLOCATED-PRIORITY sub-TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = TBD | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Allocated Priority |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD
Length: 4 octets
Value: This contains allocated priority value for each PCE
server. The priority value can be allocated based
on PCE load or incoming request to the PCE server.
3.1. Use of PCE-ALLOCATION-PRIORITY sub-TLV for PCE discovery
Multiple servers can be present in a single network for redundancy in
which case each PCE server is allocated with a priority value. The
priority can be allocated based on PCE load (e.g., incoming request
to the PCE server) announced as attribute in the OSPF advertisement.
The PCC can be configured to use the highest priority PCE server that
is available or specify the priority of a computation request when
multiple PCEs has already been found using OSPF[RFC5088].
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4. Security Considerations
This document raises no new security issues beyond those described in
[RFC5088].
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5. IANA Considerations
IANA maintains the registry for the TLVs. PCE-allocated-priority
sub-TLV will require one new type code per sub-TLV defined in this
document.
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6. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997.
[RFC5088] Le Roux, JL., "OSPF Protocol Extensions for Path
Computation Element (PCE) Discovery", RFC 5088,
January 2008.
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Author's Address
Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: sunseawq@huawei.com
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