Design of CapEx and OpEx aware IP-over-WDM network using different types of traffic bypass and grooming techniques

Abstract

To improve efficiency in setting up and operation of IP-over-WDM (IPoWDM) network, the network can be designed by minimizing either the capital expenditure (CapEx) or the operational expenditure (OpEx) in the planning phase. However, the CapEx-aware designed network may differ from the OpEx-aware designed network. Thus, Capex and OpEx need to be considered together to develop an expenditure-efficient network for a given planning period. Lightpath bypass and traffic grooming techniques help to minimize the required line card number in the core IP router. We design an expenditure (i.e., CapEx and OpEx put together for a given planning period) efficient IPoWDM network. We also review the effect of lightpath bypass and traffic grooming in the design. To design IPoWDM networks, we develop an optimization model and auxiliary-matrix-based heuristics to reduce the network’s total expenditure. The proposed methods judiciously deploy the network equipment at different places to reduce the total expenses and provide solutions for traffic grooming and placement of regenerators. We assume a realistic network framework where the bidirectional WDM equipment has finite transparent reach limit. The performance analysis shows that the multi-hop bypass approach provides more expenditure-efficient networks compared with the direct bypass and the non-bypass methods.