Turaci, T.2024-09-292024-09-2920192146-1147https://hdl.handle.net/20.500.14619/10140Computer scientists and network scientists want a speedy, reliable, and non- stop communication. In a communication network, the vulnerability measures the re- sistance of the network to disruption of operation after the failure of certain stations or communication links. The average lower 2-domination number of a graph G rela- tive to a vertex v is the cardinality of a minimum 2-dominating set in G containing v. Consider the graph G modeling a network. The average lower 2-domination num- ber of G, denoted as ?2av(G), is a new measure of the network vulnerability, given by ?2av(G) = 1/|V(G)|?v?V(G) ?2v(G). In this paper, above mentioned new parameter is defined and examined, also the average lower 2-domination number of well known graph families are calculated. Then upper and lower bounds are determined and exact formulas are found for the average lower 2-domination number of any graph G. © Işik University, Department of Mathematics, 2019.eninfo:eu-repo/semantics/closedAccessAverage lower 2-domination numberConnectivityDom- ination numberGraph vulnerabilityNetwork design and communicationArticle2-s2.0-850746038866653Q46589