Abstract
Connectivity index (CI) has a vital role in real-world problems especially in Internet routing and transport network flow. Intuitionistic fuzzy graphs (IFGs) allow to describe two aspects of information using membership and nonmembership degrees under uncertainties. Keeping in view the importance ofCIs in real life problems and comprehension of IFGs, we aim to develop some CIs in the environment of IFGs. We introduce two types of CIs, namely, CI and average CI, in the frame of IFGs. In spite of that, certain kinds of nodes called IF connectivity enhancing node (IFCEN), IF connectivity reducing node (IFCRN), and IF neutral node are introduced for IFGs. We have introduced strongest strong cycles, theta-evaluation of vertices, cycle connectivity, and CI of strong cycle. Applications of the CIs in two different types of networks are done, Internet routing and transport network flow, followed by examples to show the applicability of the proposed work.