Towards the maximum resource sharing degree for survivable IP/MPLS over WDM mesh networks
Introduction
Survivability is a key property for IP/MPLS over WDM mesh networks since the failures of the network components may induce a large amount traffic loss and the degradation of network performances [1], [2]. In this paper, we focus on the protection technique for survivable two-layer mesh networks: Label Switched Path (LSP) protection on IP/MPLS layer and lightpath protection on WDM layer [3], [4]. For the case of LSP protection, the physical path of backup LSP must be link-disjoint of that of corresponding working LSP. The working LSPs of some connections and the backup LSPs of other connections are allowed be carried into the same lightpath. For the case of lightpath protection, the working LSPs are separately carried on one lightpath named the working lightpath. And the path of backup lightpath should be link-disjoint of that of corresponding working lightpath on WDM layer. The LSP protection and the lightpath protection both deal with the situation of link failure for IP/MPLS over WDM mesh networks. Contrast to the LSP protection, the lightpath protection is coarse-grained that result in poor resource sharing degree [5].
Fig. 1(a) and (b) illustrates the LSP protection and the lightpath protection on survivable IP/MPLS over WDM mesh networks, respectively. In Fig. 1(a), the working LSP from router A to router E is groomed in LightPath (i.e., LP) 1 and the backup LSP is multi-hop groomed in (LP 2, LP 3, LP 4, LP 5). If physical link (OXC A′–OXC E′) is disrupted, the working LSP from router A to router E on top layer cannot maintain, then the traffic is switched into the backup LSP. In Fig. 1(b), the working LSP is carried onto the lightpath (i.e., working LP) from OXC A′ to OXC E′. The backup LP is from OXC A′, passing through OXC B′, then to OXC E′. If physical link (OXC A′–OXC E′) is disrupted, the working LP from OXC A′ to OXC E′ on bottom layer fails, then the traffic is switched to the reserved backup lightpath: OXC A′–OXC B′–OXC E′.
One of important aspects related to protection technique on survivable IP/MPLS over WDM mesh networks is how to efficiently allocate network resource, especially for spare resource against to future link failures. In this paper, we study to improve the resource sharing degree as far as possible and propose Inter-Layer Mixed Resource Sharing (ILMRS) scheme against single-link failure, which includes two cases: Backup LSP Sharing Working Lightpath (BLSWL) and Working LSP Sharing Backup Lightpath (WLSBL). The ultimate objective of the ILMRS is to minimize backup resource consumption in a two-layer mesh network and accommodate more connection requests into the network given a network resource. Considering of dynamic characteristics of the traffic on IP/MPLS layer, we present a new auxiliary graph adding Mixed Sharing Wavelength Edge (MSWE) to realize the proposed scheme.
The rest of this paper is organized as follows: Section 2 gives the related work and our motivation. Section 3 formally presents the network model and the problem. Section 4 presents the new auxiliary graph approach. Section 5 describes in detail our proposed ILMRS scheme. Section 6 presents numerical results and Section 7 concludes this paper.
Section snippets
Related work
The problem of resource allocation for the protection on survivable IP/MPLS over WDM mesh networks has been studied by several researchers in the literature. Correspondingly, the resource sharing schemes for survivable IP/MPLS over WDM mesh networks can be classified into two categories: the Single-Layer Backup Resource Sharing (SLBRS) [6], [7], [8] and the Inter-Layer Backup Resource Sharing (ILBRS) [9], [10], [11], [12], [13]. In the SLBRS scheme, the backup resource of the same layer can be
Network model and problem statement
In this section, we describe the network model and problem addressed in this paper.
Mixed sharing auxiliary graph
The Auxiliary Graph (AG) has been studied extensively in the previous works [14], [15], [16]. In our study, to realize the route calculation with facility, a Mixed Sharing Auxiliary Graph (MSAG) Model is generated. The definition of edges for MSAG is shown in Table 1. The difference between traditional AG and our MSAG is that AG is always a layered graph with (w+2) layers (where w is the number of wavelengths on the physical link), while MSAG is a layered graph with (w+3) layers. In MSAG, layer
The proposed ILMRS scheme
In this section, we propose the ILMRS scheme based on the MSAG model, including two cases: BLSWL and WLSBL. The ILMRS scheme provides a feasible solution to maximize the network spare resource sharing degree. To simplify the explanation of the scheme presented hereafter, we define the following notations:
- C
the dynamic connection request of IP/MPLS layer arriving at the network.
- sC
the source node of C.
- dC
the destination node of C.
- BC
the bandwidth of C.
- PC
the protection type of C, in the context, 0
Simulation model
In this section, we present numerical results for our proposed scheme through computer simulations, which are coded in C++ and run on a lightly-loaded PC with 2.1 GHz CPU and 1 GB memory.
In the simulation, the bandwidth of traffic connection is uniformly distributed in the range of (1, 30). The maximum capacity of a wavelength is assumed to be 48. And the electronic grooming capability for each node G is 48. We consider a dynamic network traffic model. Connections are set up and torn down
Conclusion
In this paper we focus on the problem of two layer protection in IP/MPLS over WDM mesh networks. Our objective is to maximize resource sharing degree as far as possible and propose ILMRS scheme. Differing from previous studies, ILMRS allows some working paths and inter-layer backup paths to share one mixed sharing wavelengths. Therefore the ILMRS excels the SLBRS and the ILBRS in terms of blocking probability and spare resource sharing degree.
Acknowledgments
This work is supported by the National Natural Science Foundation of China (NSFC) under Grant no. 61201129 and Program for Changjiang Scholars and Innovative Research Team in University.
References (16)
- et al.
Survivable integrated grooming in multi-granularity optical networks
Optical Fiber Technology
(2012) - M. Kodialam, T.V. Lakshman, Integrated dynamic IP and wavelength routing in IP/MPLS over WDM networks, in: Proceedings...
- et al.
A joint resilience scheme with interlayer backup resource sharing in IP/MPLS over WDM networks,
IEEE Communications Magazine
(2004) - et al.
Spare capacity allocation in two-layer networks
IEEE Journal on Selected Areas in Communications
(2007) - et al.
Traffic grooming for survivable WDM networks—shared protection
IEEE Journal on Selected Areas in Communications
(2003) - N.S.C. Correia, M.C.R Medeiros, Recovery time analysis of WDM protection schemes, in: Proceedings of International...
- et al.
Resilient traffic grooming for WDM networks
OSA Journal of Optical Networking
(2008) - et al.
Path-based routing provisioning with mixed shared protection in WDM mesh networks
IEEE/OSA Journal of Lightwave Technology
(2006)
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