Complex network based comparative analysis of Delhi Metro network and its extension

Recently, cities are expanding due to population growth and migration from rural areas. This phenomenon has caused baffling traffic congestions. Metro network is a viable solution to tackle this problem. With the expansion of cities Metro infrastructure is required to be updated and expanded. Delhi city and Delhi Metro network is a typical example of this case. Delhi Metro network is undergoing expansion and it is scheduled to be completed by the year 2021. In this work, a complex network based comparative analysis of existing Delhi Metro (DMop) network and its extension (DMext) is performed. The results show that degree distribution and parameters related to degree are almost same in both networks. The local connectivity will improve marginally but global connectivity will fall significantly (15%) for DMext. The transport capacity of DMext will increase by 64% compared to DMop. To study the connectivity vulnerability and functionality vulnerability, five malicious attacks protocols are deployed. Two malicious hybrid attack protocols are proposed which are more efficient compared to other malicious attack protocols available in literature. Pertaining to functionality, it is found that if same fraction of nodes (or edges) is attacked in both networks then DMext is slightly more vulnerable as compared to DMop. But, if same number of nodes (or edges) is attacked under any attack protocol then the DMext is more robust. In case of connectivity, DMext is slightly more vulnerable for same fraction of nodes attacked as well as for same number of nodes attacked. (C) 2019 Published by Elsevier B.V.