Arshad, M. J., H. Ahmad, M. Samiullah, and A. Basit. “ISP-BASED MPLS VPN: OVERVIEW, TRAFFIC ENGINEERING SERVICES AND SOLUTIONS”. The Nucleus, vol. 51, no. 1, Feb. 2014, pp. 117-24, http://thenucleuspak.org.pk/index.php/Nucleus/article/view/728.