The border is a strategic area within the Republic of Indonesia because it has potential natural resources and market opportunities and is related to aspects of sovereignty, defense and security. The division of the Papua region based on astronomical lines causes the traditional region, inhabited by tribes with the same spiritual-culture, to be divided into two countries. The Kanum tribe, who live in the border region of PNG and Indonesia, have close kinship relations. This research aims to analyze the social interactions of cross-border communities, especially the interdependence of the Kanum Tribe in Sota, Merauke Regency, with Papua New Guinea. The research used social interaction theory and interdependence theory, as well as qualitative descriptive methods by interviewing 15 informants. The research results support Polanyi’s statement but refute Omolomo’s, confirm positive competition, and eliminate indicators of conflict in the social interactions of the Kanum Tribe. The main problem found was unclear population data for the Kanum community who live in PNG but receive facilities from Indonesia. The dominant inhibiting factor comes from the PNG border condition, and the dominant supporting factor comes from the Sota border conditions (geography, infrastructure, economics and government policy). However, the condition that is equally a during factor in the conditions of the PNG and Sota borders is culture.

The purpose of the article is to examine the changes in cross-border cooperation between Vietnam and China as a result of the development and connectivity of cross-border infrastructure between the two countries. This article is based on a mixed-methods study that includes desk research and surveys. The article explains how the two countries’ approaches to border shifted from ‘barrier’ to the border of ‘connectivity’. Accordingly, the article examines the changes in border management cooperation between the two countries, which serves as a vital basis for cross-border development cooperation. Furthermore, the article examines the perceptions of the two countries regarding the development and connectivity of cross-border infrastructure for comprehensive cooperation between the two countries and beyond. At the same time, the article examines how the two countries promote the development and connectivity of cross-border infrastructure, both hard and soft. The article also examined some initial results and some issues facing the two countries. The paper concludes with some findings. In particular, the article concludes that increased border connectivity will encourage cross-border cooperation and integration between the two countries and help to alleviate security concerns. Although the two countries have made efforts to open their borders, in the transition from a border of ‘barriers’ to a border of ‘connectivity’ remain partly to Vietnamese people’s memories of the 1979 Sino-Vietnamese border war, as well as the impact of the two countries’ unresolved South China Sea disputes. However, Vietnam also tries to promote cross-border cooperation within a controllable level.