Performance evaluation of wavelength band switching in multifiber all-optical networks

Abstract

Abstract-Wavelength band switching (WBS) has only recently attracted attention from the optical networking industry for its practical importance in reducing the control complexity and cost of optical cross-connects (OXCs). However, WBS-related problems of theoretical interest have not been addressed thoroughly by the research community, and many issues are still wide open. In particular, WBS is different from wavelength routing, and thus techniques developed for wavelength-routed networks (including e.g., those for traffic grooming) cannot be directly applied to effectively address WBS-related problems.In this paper, we first propose a new multi-granular OXC (MG-OXC) architecture for WBS, which is more flexible than any existing WBS node architectures. We also adopt the most powerful waveband assignment strategy, and develop an efficient heuristic algorithm called Balanced Path routing with Heavy- Traffic first (BPHT). To verify its near-optimality, we also develop an integer linear programming (ILP) model. Both the ILP and the BPHT algorithms can handle the case with multiple fibers per link and hence are more general than our previous single-fiber solutions [1].We conduct a comprehensive evaluation of the benefits of WBS through detailed analysis and simulations. We show that the proposed heuristic BPHT can perform much better than a heuristic which applies the optimal routing and wavelength assignment (RWA) method. We also show that WBS using BPHT is even more beneficial in multi-fiber networks than in single-fiber networks in terms of reducing the port count. Our analytical and simulation results also provide valuable insights into the effect of wavelength band granularity, as well as the trade-offs between the wavelength-hop and the port count required in WBS networks.

Multi-Granular Optical Cross-Connect: Design, Analysis, and Demonstration

“…The principle of multi-granular optical crossconnects that can switch traffic at fiber, waveband, and wavelength granularities [16][17][18] has been proposed to reduce the cost and complexity of traditional OXCs. The MG-OXC is a key element for routing high speed WDM data traffic in a multi-granular optical network.…”

Recent Developments in and Challenges of Photonic Networking Technologies

“…The recently developed algorithms [59] extend those developed in [57] so that a protection path that shares no nodes or links with the working path (link and node disjoint) can be established and wavelength conversion is considered. The issues discussed in the paper are related to hierarchical LSP networks where the n:1 relationship between LSP and OLSP (Optical Label Switched Path) is considered (n ≥ 1); other types of hierarchical networks have been extensively studied as in [60]- [62]. The objective and network conditions stated in [60] are different from those considered here.…”

“…The authors in [60] try to improve the network throughput under given optical network resources, while enforcing constraints on one pair of fibers between nodes. Other papers [61], [62] assumed multi-layer networks comprising waveband and wavelength paths. Each waveband can accommodate a fixed set of wavelengths, which imposes very severe restrictions on wavelength assignment (see 4.1.4).…”

Service-Oriented Multigranular Optical Network Architecture for Clouds

“…The principle of multigranular optical cross-connects (MG-OXCs) that can switch traffic at fiber, waveband, and wavelength granularities [7][8][9] has been proposed to reduce the cost and complexity of traditional OXCs. The MG-OXC is a key element for routing high-speed WDM data traffic in a multigranular optical network.…”