Rahman, T. “IMPLEMENTASI VIRTUAL PRIVATE NETWORK OVER GRE TUNNEL”. JITK (Jurnal Ilmu Pengetahuan Dan Teknologi Komputer), vol. 3, no. 1, Aug. 2017, pp. 1-8, https://www.ejournal.nusamandiri.ac.id.103-80-238-135.cpanel.site/index.php/jitk/article/view/330.