Single-path provisioning with multi-path recovery in flexgrid optical networks

Abstract

Abstract-The new flexgrid technology, in opposition to the fixed grid one traditionally used in wavelength switched optical networks (WSON), allows allocating the spectral bandwidth needed to convey heterogeneous client demand bitrates in a flexible manner so that the optical spectrum can be managed much more efficiently. In this paper we propose a new recovery scheme, called single-path provisioning multi-path recovery (SPP-MPR), specifically designed for flexgrid-based optical networks. It provisions single-paths to serve the bitrate requested by client demands and combines protection and restoration schemes to jointly recover, in part or totally, that bitrate in case of failure. We define the bitrate squeezed recovery optimization (BRASERO) problem to maximize the bitrate which is recovered in case of failure of any single fiber link. A mixed integer linear programming (MILP) formulation is provided. Exhaustive numerical experiments carried out over two network topologies and realistic traffic scenarios show that the efficiency of the proposed SPP-MPR scheme approaches that of restoration mechanisms while providing recovery times as short as protection schemes.Index Terms-Flexgrid optical networks, Single-path Provisioning Multi-path Recovery, Bitrate squeezing.

On efficient protection design for dynamic multipath provisioning in elastic optical networks

“…(6) shows that the optimization objective is to minimize the total number of links in the protection structure. Constraints:…”

“…Meanwhile, improving network survivability with protection is not only important but also necessary in EONs, since a single link failure can cause huge data loss due to the high transmission rate [5]. In order to address this, previous studies have investigated both the path-based and link-based protection schemes for singlepath provisioning (SPP) in EONs [5][6][7][8][9]. A bandwidth squeezed restoration scheme for dedicated path-protection in EONs has been proposed in [5].…”

“…A bandwidth squeezed restoration scheme for dedicated path-protection in EONs has been proposed in [5]. To efficiently utilize EON's spectral segments for path-protection, the authors of [6] designed a multipath recovery scheme for SPP. The problem of static routing and spectrum assignment (RSA) for EONs with dedicated path-protection was investigated in [7].…”

Analytical performance modeling of elastic optical links with aligned spectrum allocation

“…A brute-force approach is to keep track of each frequency slot whether be idle or occupied and if occupied which class of demands is using it [22]. One may then solve a Markov chain of size (K + 1) N which is not feasible for large values of N. For example, if the entire spectrum is set to 1.6 THz as in [26], then the EOL capacity would be N = 128 when the slot width is set to 12.5 GHz as in [27]. Consequently, the brute-force approach would fail for any choice of K ≥ 2.…”

Proteção compartilhada e restauração de tráfego em redes ópticas de segmentação espectral flexível

“…O algoritmo MILP proposto em [29] Embora o artigo esteja dentro do contexto de proteção compartilhada, o algoritmo está fora do escopo deste trabalho, pois nosso objetivo é proteger a rede contra uma única falha.…”