An Efficient Recovery A pproach for Protection LSP Supervisor Professor : 林振緯 Speaker : ...
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Transcript of An Efficient Recovery A pproach for Protection LSP Supervisor Professor : 林振緯 Speaker : ...
An Efficient Recovery Approach for Protection LSP
Supervisor Professor : 林振緯
Speaker : 蘇文宏
Computer Science and Information Engineering Department
Fu Jen Catholic University
•Abstract•Introduction-MPLS Recovery Mechanisms •Recovery Time Model•My New Efficient Recovery Approach•Conclusion and Future Work•Reference
Outline
Abstract
• A next generation backbone architecture.• “Fault Recovery” has become an important research in
MPLS.• IETF has made strict definitions for MPLS Recovery in
RFC 3469 in February,2003.• The paper propose An Efficient Recovery Approach t
o handle fault recovery,we finally compare other approachs and demonstrate our proposed approach by several experiments is better.
Introduction-MPLS Recovery Mechanisms
There are three options for the “Initiation of the recovery path setup[1]:”
1.Pre-Established.
2.Pre-Qualified.
3.Established-on-Demand.
Introduction-MPLS Recovery Mechanisms(cont.)
Recovery path type Recovery path setup point
pros cons
Pre-EstablishedBefore fault
斷線恢復時間短 •資源可用率差•備用路徑不見得是最佳路徑
Pre-QualifiedBefore fault
資源可用率比 Pre-Established 高
•斷線恢復時間比 Pre-Established 稍長•備用路徑不見得是最佳路徑
Established-on-Demand
After fault
•資源可用率最好•備用路徑也是斷線時的最佳路徑
斷線恢復時間長
Introduction-MPLS Recovery Mechanisms(cont.)
There are two main options for the “Topology of recovery”[1]:
1.Local Repair.
2.Global Repair.
Introduction-MPLS Recovery Mechanisms(cont.)
1.Local Repair(Link Recovery or Node Recovery).
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9 10Break
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9 10Break
Link Recovery
Node Recovery
Introduction-MPLS Recovery Mechanisms(cont.)
2.Global Repair.
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9 10Break
POR/PSL
(Ingress)
PML
(Egress)
FISBreak
Introduction-MPLS Recovery Mechanisms(cont.)
Local-to-Egress Repair[2]
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9 10Break Break
Introduction-MPLS Recovery Mechanisms(cont.)
There are two options for the “Recovery Model”[1]:
1.Rerouting.• Recovery by rerouting is defined as establishing new paths or path
segments on demand for restoring traffic after the occurrence of a
fault.
2.Protection Switching.• pre-establish a recovery path or path segment, the recovery path may
or may not be link and node disjoint with the working path, a fault is detected, the protected traffic is switched over to the recovery path(s) and restored.
Introduction-MPLS Recovery Mechanisms(cont.)
Recovery model
Recovery path type
Recovery path setup point
Recovery time
Resource utiltization
Reliability
Rerouting Pre-qualified
Establish-on-demand
After fault 3
4
1
1
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3
Protect switching
Pre-e
Stabli 1 + 1
Shed
1:1,1:n,
m:n
Beforce fault
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2
1
2
Introduction-MPLS Recovery Mechanisms(cont.)
Proposed approach presently:• Haskin Approach[3].• Makam Approach[4].• Das Approach[5].• Hundessa Approach[6].• RSVP Approach[7].• Yoon Approach[8].• Dynamic Approach[9].
Introduction-MPLS Recovery Mechanisms(cont.)
• Haskin Approach.
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9 10Break
POR/PSL
(Ingress)
PML
(Egress)
Break
Introduction-MPLS Recovery Mechanisms(cont.)
• Makam Approach.
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9 10Break
POR/PSL
(Ingress)
PML
(Egress)
FIS
Introduction-MPLS Recovery Mechanisms(cont.)
• Das Approach.
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9 10Break
POR/PSL
(Ingress)
PML
(Egress)
FIS
FIS
FISFIS
FIS
6
Temporary backup path
Introduction-MPLS Recovery Mechanisms(cont.)
• Hundessa Approach(Improve Haskin Approach).
1 Break2
Tag
BufferPOR/PSL
(Ingress)
Tag
Working path
Backup path
Introduction-MPLS Recovery Mechanisms(cont.)
• RSVP Approach.
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9 10Break
POR/PSL
(Ingress)
PML
(Egress)
Introduction-MPLS Recovery Mechanisms(cont.)
• Yoon Approach.
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Break
POR/PSL
(Ingress)
PML
(Egress)
Introduction-MPLS Recovery Mechanisms(cont.)
• Dynamic Approach.
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9 10Break
Introduction-MPLS Recovery Mechanisms(cont.)
Recovery Methods
Pros. Cons. Local repair
Global repair
Haskin •Packet loss 少•Switch backup fast
Reorder 較嚴重 * *
Makam •幾乎沒有 Reorder 問題 Packet loss 較多 *
Das •Packet loss 少 FIS 傳送路徑長,恢復時間長
*
Hundessa •Packet loss 少•不會有 reorder 情況
LSR 負擔較大,成本較高, buffer overflow 問題
*
RSVP •Packet loss 少•不會有 reorder 情況•Switch backup fast
Backup path 可能會發生頻寬不足的問題
*
Yoon 能取得較佳路徑 LSR 資料維護量較大,負擔重
*
Dynamic •高頻寬使用效率•低負載
服務中斷時間較長 *
Recovery Time Model
[9]
Recovery Time Model(cont.)
[9]
[9]
Recovery Time Model(cont.)
(4)
(5)
(6)
(1)
(2)
(3)
[9]
My New Efficient Recovery Approach
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Break
POR/PSL
(Ingress)
PML
(Egress)
Conclusion and Future Work(cont.)
Future work(Schedule)
時程 進度
暑假 完成 NS2 模擬
研二 ( 上 ) 目標:發表一篇 Conference paper
研二 ( 下 ) 論文
Reference
1.V.Sharma, F.HellstrandAndersson, , “Framework for Multi-Protocol Label Switching (MPLS)-based Recovery”, RFC 3469, February 2003.
2. A. Autenrieth and A. Kirstadter, “Engineering End-to-End IP Resilience Using Resilience-Differentiated QoS,” IEEE Communication Magazine, Volume 40,Issue 1, January 2002, pp.50-57.
3. D. Haskin and R. Krishnan, “A Method for Setting an Alternative Label Switched Paths to Handle Fast Reroute,” Internet-Draft(draft-haskin-mpls-fast-reroute-05.txt), November 2000.
4.S.Makam, V.Sharma, K.Owens, and C.Huang, “Protection/Restoration of MPLS Networks,” Internet-Draft (draft-makam-mpls-protection-00.txt), October 1999.
5.S.K. Das and P. Venkataram, “A method of Designing a path restoration scheme for MPLS based network”, High Speed Networks and Multimedia Communications 5th IEEE International Conference on, 2002, pp.218-222.
Reference(cont.)
6.L. Hundessa and J. D. Pascual, “Fast Rerouting Mechanism for Protected Label Switched Path”, IEEE Computer Communications and Networks, 2001.Proceedings. Tenth International Conference on 2001, pp.527-530.
7.Ping Pan, Der-Hwa Gan, George Swallow, Jean Philippe Vasseur, Dave Cooper,Alia Atlas and Markus Jork, “Fast Reroute Extensions to RSVP-TE for LSP “,Internet draft <draft- ietf-mpls-rsvp- lsp- fastreroute-02.txt>, work in progress.
8.Sangsik Yoon, Hyunseok Lee, Deokjai Choi, Youngcheol Kim, Gueesang Lee and Lee M., “An efficient recovery mechanism for MPLS-based protection LSP”,IEEE International Conference on, 2001, pp. 75-79.
9.G. Ahn, and W. Chun, “Simulator for MPLS Path Restoration and Performance Evaluation”, IEEE, 2001.
Reference(cont.)
10.Achim Autenrieth,”Recovery Time Analysis of Differentiated Resilience in MPLS”,Design of Reliable Communication Networks(DRCN)2003,Banff,Alberta,Canada,October 19-22,2003